Wastewater Analysis - Science topic

Zahra Khodaparast Chromatography is a more reliable method to determine biodegradability, as it:

- Provides a detailed breakdown of organic compounds

- Identifies specific biodegradable and non-biodegradable fractions

- Offers a more accurate assessment of biodegradability potential

- Complements BOD5/COD analysis with more comprehensive information.

I would suggest

Cu₂O + Pb(2+) + H₂O --->2Cu⁺ + Pb(OH)₂ (my recollection is that Pb(OH)₂ is less soluble than Cu₂O/CuOH)

2Cu⁺ + 1/2O₂ + H₂O ---> 2Cu(2+) + 2OH^- ---> Cu(2+) + Cu(OH)₂ (oxygen in water does play a role)

Viscosity increases with temperature for gases and decreases with temperature for liquids. Kinematic viscosity is absolute viscosity divided by density, e.g. Temperature, viscosity and density must be in consistent units, and under the same conditions.

to answer your question well I want to know how you do the electrolysis? is it by electrocoagulation?

Electrochemical treatment on real wastewater or contaminated water works best, but in the water/wastewater pH band of 6 to 8 only, with or without aid.

To answer one aspect of your question: In electrolysis, an electrolyte should be present to allow a sufficiently high conductivity of the aqueous medium. Water is a bad conductor, so adding something like Na2SO4 that is a) well dissociated and b) is not easily reduced/oxidized at the electrode is certainly a good approach.

This is a typical calibration procedure. You will need multiple concentrations to develop a quantitative response relation that you will use to estimate concentrations in your samples

If you want to some basic ideas about that then you go for S k garg. And if you want to know deep knowledge about that then go for Metcalf and Eddy. It's clear all the concepts from basics to advance.

Yes you can.

Tannery effluent have large amount of Cr. Iron also may be present in many type of wastewater due to treated systems and pipe. Cu I don't find it in most copper industries wastewat such as wire. Ni and Co in the military industries wastewater. In fact the presence of heavy metals depending on both industry effluent and regulation limits. I mean some regulations accepted high concentration of heavy metals in wastewater.

Dilution factor = BOD (mg/l)/ (Initial DO - Final DO)

In the case of the bipolar electrodes, each one of the electrodes, excluding the external ones, which are monopolar, present different polarity at each one of the electrode sides depending on the charge of the electrode in front it. The connection of bipolar electrodes is permanently in serial mode.

Kinetic studies of treatment process have major role in determining the hydraulic retention time in any reactor system to achieve desired removal efficiency. Consequently, rate constant is very significant in the design of wastewater treatment units. It is very fundamental to know the type of reaction rates for design a wastewater treatment unit. Rate of reaction describes the rates of change in concentration of reactant per unit time.

The electrolytes play a major role in the EC process due to the possible formed side products that can increase or decrease the efficiency of the system.

NaCl, This may be explained by the fact that the higher Cl− concentrations related to ability of Cl− to damage any passive oxide film which tends to form on anodes at relatively high potential and limit electrod dissolution.

In most cases the underperformance of clarifier is because of the faulty hydraulics. I suggest to check for inlet energy dissipation device, central baffled wall and try to optimize the same. The other design parameters which need attention are surface overflow rate (SOR), hydraulic retention time (HRT) and weir over flow rate. Apart from these, there are hardly any governing parameters which decide the performance of clarifier, generally.

No idea, my supervisor collected them a year ago somehow!

This Question which interested me a lot, thank you very much

k_La is a very important design parameter for wastewater aeration. I have studied the energetic optimization and adaptive control of the dissolved oxygen concentration in aerobic fermenters by numerical simulation. The parameters of the usual KLa correlation were estimated on-line and at real-time through the recursive least squares algorithm with forgetting factor, most effectively when a small sinusoidal disturbance was imposed to the manipulated variables (stirring rate and/or air flow). The power dissipated by agitation was accessed by a torque meter (pilot plant). This investigation was reported at (MSc Thesis):

these links may help

Regards

Vijay Sodhi

I agree about the high turbidity in the outlet of poorly designed and/or operated wastewater treatment plants (WWTP's) as I have witnessed worldwide over more than 40 years. Precisely this poor performance of so many WWTP's was the reason why we upgraded the conventional activated sludge (CAS) process to our advanced activated sludge (AAS) process to complement our high-rate anaerobic digestion (HRAD) process converting high levels of organics (TOC, COD) to green energy (biomethane) for a broad range of industrial wastewaters.

Dear https://www.researchgate.net/profile/Aarif-Shah-2 , Just ensure that DAD detector is working on VW ( Variable Wavelength ) priciple but UV detector is working on Lambert Beers law principle entirely different . You are again requested to calculate manually % RSD between two wavelengths ( not more than 2 % ) .Please go through the deatail - https://www.ssi.shimadzu.com/products/liquid-chromatography/knowledge-base/hplc-basics/uv-vs-pda-detectors.html

Further manual calculation of % RSD are suggested since two instruments are on defferent platform .

For cell counting you can just add 1-2 drops of lugol solution to a 10 ml sample and store it.

For lipid determination, I recommend you to store your Microalgae pellet in the own extraction solvent with an antioxidant (BHT is commonly used) and inert (N gas) atmosphere in the freezer (-20-40ºC is OK)

Chemical Oxygen demand is indirect measure of total organics present in water. There are two types of organic in water, bio-degradable and non-biodegradable. Bio-degradables are measured as Biological Oxygen Demand (BOD).

Non bio-degradable = COD - BOD

For COD strong oxidizing agent is used such a potassium dichromate (PDC) solution of known strength. A know volume of oxidising agent is added and digested in acidic medium (H2SO4). The unused dichomate is measured with the help of Farious ammonium sulfate (FAS) of known strength.

COD (mg/l)=

ml of PDC*N of PDC*8000/ml of sample

Overall the current urgent topic in wastewater treatment is to turn the wastewater to energy and resources, including clean healthy water. I believe that the self-sustaining synergetic microalgal-bacterial granular sludge process is one of the directions. Second，membrane technology is also one of the hot topics to produce healthy clean water in 21st century. Third，Microbial fuel cell based technology might be one topic.

Since you have only two months to complete the project, you do not have the option to fly to collect new topo data. Your option is pretty much limited to using the best available topo data. This is a common situation encountered by practicing engineers.

It is always good to make use of standard when you do this kind of research. In membrane filtration technique as you describe, mEndo is preferred for coliform test.

Any contaminated resource which is present in the ecosystem.

I see some very good answers - we do the estimation by measuring the change in thermal conductivity of the space. The measurement can be more meaningful if you know the composition of the mineral deposit. The thermal conductivity of common water system scales is known. If the accumulation is, in fact, deposited, not grown in place - then the thermal conductivity model would be more relevant within repeated accumulation/settling of solids in that location.

Thermal conductivity is an accurate means of measuring the relative thickness but the results are more material with repeated measures or an accurate knowledge of the physical and chemical composition of the matter of interest.

It's really a complex process. Types of contaminants, their chemical nature, and reactivity towards each other; are some practical issues. We really need some improved methods and materials that can be implemented in economically efficient ways as well. Besides it, in my opinion, we should focus on in situ treatment of at least point source of pollutants.

Some very informal notes about gravimetry:

The solids in a fluid could be classified in several ways. Let’s take an example: if you make tea, putting the leaves on the teapot, with hot water for some minutes, if you screen/filter the liquid you will drink or beverage that is dissolved solids in hot water. The material retained in the filter or mesh are the suspended solids.

If you forget the teapot, with the tea leaves liquid, in the fire probably all the water will be evaporated and you’ll get a burned teapot with total suspended solids (that were able to be removed by a mesh) and the dissolved solids that was not possible to be removed in a ‘regular’ mesh.

Total solids = suspended solids + dissolved solids

The solids above also could be classified according their drying temperature, if we consider dry them at about 105°C we called total solids or total fraction (since we just remove the water). If, later, we take these solids and dry again, now in a furnace ate 550°C we lose organic matter, and the residue is called the ash or mineral fraction. The difference between ash and total weight of the sample is called volatile – and for a sanitary engineer could be related to organic matter or microorganisms in an activated sludge system.

If you do not filtrate the sample, you always will get total solids (suspended + dissolved) and according the drying temperature total fraction or fix. Sometimes for some effluents you can relate centrifuged sample with a filtrated sample, BUT it is an approximation and it is not true always.

Just to conclude I the beginning was mentioned about the tea that is could be done by means a cloth, a mesh or a filter. Usually the official standards specify the opening / or retention of the filter.

Good tea

Check if it makes sense for you:

Spiliotopoulou, A., Martin, R., Pedersen, L.-F., Andersen, H.R., 2017. Use of fluorescence spectroscopy to control ozone dosage in recirculating aquaculture systems. Water Res. 111, 357–365. doi:http://dx.doi.org/10.1016/j.watres.2016.12.036

CALCULATIONS FOR PHOSPHORUS MANAGEMENT IN WASTEWATER: Examples for consultants and regulators Dr Robert Patterson FIEAust, CPSS, CPAg Lanfax Laboratories Armidale NSW 16th December 2016 Technical Note: T16-1 Calculations for P management in wastewater Lanfax Laboratories. Armidale 16th December 2016 Page 1 of 8 CALCULATIONS FOR PHOSPHORUS MANAGEMENT IN DOMESTIC WASTEWATER Dr Robert Patterson, Lanfax Laboratories, Armidale NSW 1. Introduction Phosphorus (as phosphate PO43-) is present in domestic wastewater (50% orthophosphate, 40% polyphosphate; 10% organic phosphates) and most passes through treatment systems such as septic tanks and aerated treatment systems (AWTS) in the effluent (discharge) without any significant lowering of the concentration. A minor component (<10%) may be removed with solids in the sludge and/or scum. The reduction in risk of off-site effects from the phosphorus (P) is to contain all the P within the soil treatment area and its buffer. Risk management needs to involve spreading the P (in the effluent) over a sufficiently broad area to account for plant requirements (P is an essential macro-nutrient) and immobilisation in the soil, known as measured P sorption capacity. Annually, plants generally require about 30 kg P/ha (all plants - natives and exotics, grasses and weeds alike at varying rates), which equates to 3 g/m2. This value will be discussed later. Soil P adsorption (also called P sorption) is a unique property of the soil related to its clay mineralogy, the aluminium, iron, manganese and/or calcium, soil pH and other properties. At low pH, aluminium, iron and manganese are in ionic form and can bond strongly with the phosphate. Soil P sorption is measured in the laboratory by equilibrating soil samples with solutions of varying concentrations of phosphate and measuring the residual in the solution - that portion not adsorbed onto the soil minerals. The effects of P sorption can occur rapidly (hours to a few days) of effluent entering the soil and the reverse (desorption) is a very slow processed (years to decades), so plants have difficulty accessing the P sorbed onto the minerals/clays. 2. Questions and Calculations Assume that the wastewater from a domestic dwelling passes through a septic tank (or AWTS) at the rate of 500 L/day. A typical domestic effluent has a P concentration of about 10 mg/L. (A) What area is required to contain the P for the next 50 years? (B) Is an area of 150 m2 (calculated for the hydraulic load) large enough to adsorb P for next 50 years? (C) On an area of 150 m2 for how many years will the soil adsorb the current application? Inputs: Daily water load = 500 L (4 persons at 120 L/day – rounded to 500 L)P concentration = 10 mg/LSoil bulk density = 1400 kg/m3 (either from measurement or estimate)Soil depth = 1.0 mPlant requirement = 30 kg/haSoil P sorption = 4000 kg/ha (measured or known from other sources) Calculations: Question A: What area is required to contain the P for the next 50 years? A1. Annual load (kg) = daily load (L) x P concentration (mg/L) x 365 days 1 000 000 (convert mg to kg)= 500 x 10 x 365 1 000 000= 1.825 kg per year(NOTE: THIS SOURCE OF THIS ANNUAL LOADING WILL BE CHALLENGED LATER)A2. Calculate plant uptake and soil adsorption for 50 yearsPlant uptake for 50 years = 30 kg/ha x 50 years= 1500 kg/haSoil P adsorption for 50 years = 4000 kg/ha (measured)Total P capacity for 50 years = 1500 (plant) + 4000 (soil)= 5500 kg/haA3. Calculate area required for 50 years’ life in land application area50-year application P = 1.825 kg/year x 50 years= 91.25 kgArea required = Total load for 50 years (kg) P capacity for 50 years (kg/ha)= 91.25 kg 5500 kg/ha= 0.0166 ha= 166 m2 (1 ha = 10 000 m2)

Calculations for P management in wastewater Lanfax Laboratories. Armidale 16th December 2016 Page 2 of 8 Question B. An area of 150 m2 was designed for the hydraulic load from a water balance. Is this area sufficient to accept P over 50-year life to application area? B1. Calculate the annual uptake of P by both plants and soil. Annual plant uptake P = 30 kg/ha Annual soil P sorption uptake = 4000 kg/ha divided by 50 years = 80 kg/ha Total annual P capacity = (30 + 80) kg/ha = 110 kg/ha Total capacity for 150 m2 = 110 kg/ha x 0.0150 ha = 1.65 kg per annum B2. Is the 150 m2 large enough to sustain this annual load? Annual load = 1.825 kg (Calculated in A1)Annual capacity = 1.65 kg (Calculated in B1)Area required = Annual load (kg) Annual capacity (kg)= 1.825 1.65= 1.106 Since this value is larger than 1, area of 150 m2 is TOO small by 10%. Ideal area from this calculation = 150 m2 x 1.1 = 165 m2 Question C: On an area of 150 m2, for how many years will the plants and soil adsorb the current P application? C1 Current annual application rate = 1.825 kg (From A1) Annual plant requirement = 3 g/m2 (equivalent 30 kg P/ha)= 150 m2 x 3 g/m2 1000 (g in kg)= 0.45 kg/m2Excess plant P annually = 1.825 - 0.45 kg= 1.375 kg (Required soil P sorption)Potential capacity (years) = soil P capacity (kg/ha) x area (ha)= 4000 kg/ha x 0.0150 ha= 60 kg over land application areaLife of land application area = P capacity (kg) Annual excess (kg)= 60 1.375= 43.6 years For many systems, 43.5 years will be close enough to 50 years to be acceptable. Why 50 years? No idea! CAUTION: While the above calculations of daily water use and typical P concentration may be welcomed by regulators as providing a clear arithmetic solution to deducting a sustainable land application area for domestic wastewater, there is a real problem that disadvantages non-conservative water users. Why are calculations made on concentration at all, when LOAD is the limiting measure? Load (mass) = concentration x volume. 3. Concentration versus Load – which is correct? The calculations above have been performed on the typical concentration of P (10 mg P/L) in domestic wastewater from numerous sources. The annual load is, therefore, the concentration multiplied by the volume and 365 days. The uncertainty of load arises because the amount of P discharged into the wastewater through the diet, kitchen wastes and laundry detergents, can vary significantly from one home to another. By using concentration, one assumes that P load increases with water use, when it is independent of water use. Rather, consumption of P depends upon the number of persons in the home and how much P they consume/use. For greater accuracy, the load calculations need to be done on a ‘per person’ or ‘per household’ basis and not on wastewater generation rate. If we were to take the above calculations in A1 and use 600 L/day (reticulated water supply compared with rain water supply) for a different household, then the annual P load is 2.19 kg. From where did the extra 0.365 kg P come? Same household size (4 persons), assume typically same diet, same everything except the household uses more water. But the 20% increase in P cannot be explained. Why? Because working on concentration to determine nutrient assimilation rates is seriously flawed. Therefore, choose a different annual load for A1 above. Calculations for P management in wastewater Lanfax Laboratories. Armidale 16th December 2016 Page 3 of 8 A range of P generation rates is shown below for several countries, but the range is significant because the data have been sourced from municipal sewage treatment rather than on-site system. Monitoring on-site systems is difficult because there are very little data on actual daily water use correlated with actual daily wastewater P analysis. The only analyses available are broad averages without necessarily monitoring household use of phosphate rich products. It would not be unusual for there to be a greater through-flow of P in the wastewater on days when the laundry was done using phosphate rich detergents, or to be less when the laundry was done with phosphate free detergents. Per person P rate = 1.8 g P/capita.day (Alexander & Stevens 1976 – USA old data) Per person P rate = 1.9 g P/capita.day (Gilmour et al., 2008 – municipal samples Scotland) 4 person household = 2.8 kg P/yearPer person toilet waste = 1.6 kg P/yr (USEPA 2002 – older USA data)4 person household = 6.4 kg P/yrAverage per dwelling rate = 2 kg P/yr (Environment Canterbury, 2012 – recent NZ data) The data by Alexander & Stevens (1976) are likely to reflect laundry products with very high P concentration, as was the practice then. Over the last two decades there has been a significant decrease in the P in household laundry detergents (www.lanfaxlabs.com.au/laundry.htm) and more than half the powder and liquid laundry products in the supermarket, in 2016, have no added P (marked NP) or are very low in P (marked P). Where these ‘NP’ laundry products are used, the only contribution to the daily P load is from the diet (kitchen and toilet) and a very small contribution from bathroom in personal care products. The NSW Guidelines (1998) were written in the era when phosphate was the surfactant of choice, a thoroughly efficient surfactant, but a limit to sustainable effluent areas. Because of the shared laundry products, by detergent manufacturers in Australia and New Zealand, the Environment Canterbury (2012) rate is likely to reflect similar New Zealand and Australian loading rates for P. When the previous significant contribution from the laundry is factored into the calculation, that value is a reasonable estimate for a P conservative household. With current labelling of laundry detergents, any household can easily minimise the P use by selecting ‘NP’ or ‘P’ products, such that the only contribution to P in the wastewater is from human excreta (faeces and urine) and a very small contribution from the kitchen. 4. Unsupported assumptions about life of land application area The NSW Environment and Health Protection Guidelines On-site Sewage Management for Single Households (DLG et al., 1998) suggest 50 years as a design life for the P sorption of the effluent application area (pages 73 & 116) Further, they state that soil absorption systems can have an expected life of 5 to 15 years (page 82) and septic tanks can have an expected life of 25 years. These statements are not supported by facts and may simply be the authors’ assumptions, because they are unqualified by operational and maintenance issues and ignore site specific soil properties that may benefit from on-site effluent discharges. The Guidelines suggest buffer distances of 3 m upslope and 6 m downslope for primary treated effluent (Table 5, page 66), which in many instances more than doubles the effective nutrient assimilation area around a series of trenches. For example, three parallel 25 m trenches, each separated by 3 m occupy an area of 200 m2. When buffers of 3 m upslope and 6 m downslope are included, the combined treatment and buffer area is 630 m2. It is on the 630 m2 that the containment (assimilation) of nutrients needs to be managed, not just the area in and between trenches. Further, there are no data or reference to literature to support the statement that P sorption by the soil is expected to occur up to about a quarter to half of the P sorption capacity (DLG et al., 1998, pp 73, 113, 153). The only likely source of the discount factor is possibly in Kruger et al. (1995) relating to the use of high strength piggery effluent where ‘critical P sorption’ becomes important because of the strength of the piggery wastewater and its other constituents. That discount factor may have been picked up by the Guidelines and DEC (2004) without explanation as to the significance to low strength wastewaters as domestic wastewater. At such high application rates of P (70 mg P/L) in piggery effluent, as described by Dorahy et al. (2004), with other contributions from organics (BOD5 900 mg/L), total nitrogen (600 mg N/L), potassium (270 mg K/L), sodium (130 mg Na/L) and EC (5.3 dS/m), the effluent is likely to cause ionic competition and desorption (loss of P from the adsorption sites) together with extremely high organic concentrations and other contributions from salinity. Comparison of the effects of piggery effluent, at 87 kg P/ha.yr, to domestic wastewater, at 30 kg P/ha.yr, is like ‘chalk and cheese’. Holford et al. (1997) stated that it is possible that soil will not sorb P to its full capacity before allowing it to leach beyond the sampled depth, and P may begin to leach well before the soil it saturated. The more P is added to the soil, the more P will remain in solution and any P in solution is vulnerable to leaching. They go on to say that unfortunately, little if any field research has been done to predict the degree of P saturation required before leaching will begin. Thus, the discount factor in the Guidelines is ill-informed. Why are the regulators so keen on minimising P sorption of the land application area for domestic effluent simply by assuming a discount factor without understanding the specific implications for on-site effluent disposal for specific soil properties? One-size does not fit all because of specific soil properties that influence P sorption. Calculations for P management in wastewater Lanfax Laboratories. Armidale 16th December 2016 Page 4 of 8 When the P sorption capacity is routinely measured in the laboratory on a soil sample taken from the proposed effluent application area, discounting that value is mere speculation as the specific test takes account of potential desorption through the increases in equilibrating solution P concentration. The laboratory analysis takes account of soil properties such as pH, iron, manganese and/or aluminium, calcium, organic carbon and clay type in determining the adsorption rate. Organic matter can compete with phosphates for adsorption sites resulting in surface A horizon generally having a lower P sorption than the mineral B horizon. But a blanket discount of measured P sorption cannot be justified, even on the basis of ultra-conservative issues. The Guidelines statement, suggesting discounting, ignores precipitation of phosphate soon after the effluent meets the soil in the land application area or drainfield. Together with P sorption mechanisms, P can be effectively immobilised with a significantly low risk of leaching from the land application area. When the assimilation area, as the example above suggests, is taken into account, the land application area (including buffers) is significantly oversized. Acid soils have an abundance of iron (Fe3+) and aluminium (Al3+) ions that very strongly adsorb P. Saturated soils may have significant manganese nodules that have high affinity for P sorption. The Guidelines regard soils with pH 4.5 to 6 (Table 6) as having a ‘moderate limitation’, yet one of the requirements of the land application area is to immobilise P, but expect soils with a pH >6 to have a high P sorption (>6000 kg/ha) to both have ‘minor limitations’. Without any priority ranking of the soil features, there seems to be a problem with the Guidelines authors’ understanding of P sorption as more or less important than the other parameters. For Councils to simply take the discounting as mandatory (it is a guideline only), it would be preferable that they understand the specific soil test parameters. A blanket discount of measured P sorption cannot be justified, even on the basis of ultra-conservative issues. 5. Measurement of phosphorus sorption capacity P can be present in the soil in three forms: solution where the P is readily available to plants; labile P, more plentiful than solution P, that is not strongly adsorbed to the soil and may move into solution quickly; and non-labile P in adsorbed forms that is unavailable to plants. It is the non-labile P, the largest fraction of soil total P that is of interest in maximising the retention of P in the land application area and so prevent its loss to the wider environment. Phosphorus sorption isotherms relate mathematically the amount of P sorbed by soil to the concentration remaining in corresponding equilibrating solutions under a specified set of conditions (Rayment & Lyons, 2011). For agricultural purposes, the agronomist needs to know how to maintain a workable level of plant available P in the soil to avoid P deficiency in the pasture or crop. The phosphorus soption isotherm, as set out in Rayment & Lyons (2011) Method 9I1 provides a phosphate sorption index, reported as an index without units. Method 9I2 describes a P buffer index (PBI) that includes extractable P and P sorption for equivalent soil content of 20-160 mg P/kg in five increments. Method 9J leads to the construction of a phosphate sorption curve using equilibrating solutions yielding 2.5-250 mg P/kg. These methods provide valuable insight into the requirements of plant available P and fertiliser strategies but are poorly related to soil retention of P. Allen et al., (2001), indicated three other single point indices, plus variations, for deriving P sorption for fertiliser application, yet found these methods underestimated the total amount of P sorbed. The work by them was not suitable for adsorption rates for wastewater disposal. Holford ((1979) stated that in his research on 30 Australian soils, ‘there was no correlation at all between any of the buffering indices and phosphate uptake on these soils. His results suggest that a 4 to 5 point isotherm, giving final solution concentrations up to and including 5 mg P/L, is adequate to determine the most useful buffering indices’. This concentration is well below domestic wastewater (10 mg P/L) and shows how the indices are related to plant available P rather than immobilisation of P for environmental protection. In a wastewater treatment system, the desired outcome is to understand the capacity of the soil to bind P to prevent its movement out of the land application area, not the minimum concentration to support vigorous plant production. The two purposes are at opposite ends of the soil P sorption spectrum. Thus, the equilibrating solutions, used to determine a numerical value for the P sorption of a soil from effluent, are higher than used for agriculture (Patterson, 2001), and equilibrating solutions up to an equivalent of 1500 mg P/kg are required, six-fold higher than the Methods referenced above. The Guidelines state that “a simple test to distinguish soils on the basis of high and low P retention is described in Rayment & Higginson (1992)”, a book superseded by Rayment and Lyons (2011). The problem with this statement is that it is unclear as to whether the reference is to Method 9I1, 9I2 or 9J. Just knowing whether the value is high or low is insufficient, since later in the Guidelines (page 113) and Table 6 specific guidance values for minor, moderate and major limitations are given. Method 9I uses only one solution to give the phosphate buffer index, originally used for wheat-growing soils – that is, sufficient P in solution to sustain a wheat crop. Method 9J is used to derive an equilibrium P concentration, not the ultimate potential for P sorption. Do the regulators know which one applies? If so, it would be convenient for the laboratories and consultants to have some direction so as not to waste valuable resources on tests that have no meaningful value. But the regulators may not know which test, or amended test is applicable. Calculations for P management in wastewater Lanfax Laboratories. Armidale 16th December 2016 Page 5 of 8 DEC (2004) also simply refers to P sorption as high, moderate and low for slight, moderate and severe limitations respectively (Table 2.2) without any definitive numerical value in sorption as kg P/ha. The document makes no reference to a suitable P sorption test method, so across a number of consultants, a range of uncorrelated values may be submitted to rank as meaningless low, moderate or high. How can you calculate an area without numerical P sorption values? Patterson (2001) defined a modified P sorption index for domestic wastewater using five equilibrating solutions, a soil to solution ratio of 1:10 and a 17-hour equilibration period. The residual P in solution, that which has not been adsorbed by the soil, is measured and used to calculate the P sorption capacity. This method is similar to Methods 9I and 9J in Rayment & Lyons (2011), except the equilibrating solutions are many times higher. Figure 1 shows a typical low level P sorption capacity and Figure 2 a high P sorption capacity. The closer the measured curve to the straight line of the standards, the higher the potential P sorption. Rayment & Lyons (2011) suggest that the steeper the slope, the lower the plant available P in the soil. Higher P sorption characteristics are often measured in soils high in iron or aluminium. Blast furnace slag can be added to increase the P sorption in a low P sorption soil. Other high P sorbing products/soils can be sourced to add to the land application area, or incorporate in the trenches. The MEDLI Model (Model for Effluent Disposal using Land Irrigation) (DSITI, 2015) uses the multi-point form of the Freundlich isotherm to describe the equilibrium between adsorbed and soil solution P. MEDLI version 2 is for “designing and analysing effluent disposal systems for rural industries, agri-industrial processors (e.g. abattoirs) and sewage treatment plants using land irrigation”. In a similar approach to Figures 1-4, the user must provide numerical values as input to the modelling of plant available P in the soil solution and P adsorption. The P sorption curve is derived using six or more equilibrating solutions, together with measuring extractable P to give the Y-axis starting point. Burkitt et al., (2008) dispute the addition of the exchangeable P to the soil buffering measures. While MEDLI is used extensively in Queensland for domestic wastewater assessments, possibly for dubious reasons, the model parameters are only specific for kikuyu and tropical pasture, ryegrass and temperate pasture and sorghum pasture, with no suggested inputs for lawns and small domestic irrigation areas. A significant data set is required to run MEDLI, a costly exercise for domestic systems. Figure 1 Low level P sorption Figure 2 High level P sorption Note: the calculated P sorption capacities, in Figures 1-4, are for an equivalent depth of soil of 1 m, for an assumed bulk density of 1400 kg/m3. It will be necessary to alter the P sorption capacity for shallower or deeper soils. While P sorption can occur in a period of a few hours or days, desorption (the loss of soluble P from the adsorbed site) is a lengthy process that requires specific soil conditions and whether iron, aluminium or calcium ions are involved. The testing with elevated P concentrations accounts for a desorption that may have occurred during the testing, particularly that due to the high strength equilibrating solution. Figure 3 Psorbed (mg P/kg) against log C (ug P/L) Figure 4 Psorbed (mg P/kg) against log C (ug P/L) In Figures 3 and 4, the curve is extrapolated to the X-axis to determine the critical P concentration for agricultural purposes (soil solution P for adequate plant growth). The phosphate buffer index is taken as the slope of the line. standards 0 250 500 750 1000 1250 1500 1750 250 500 750 1000 1250 1500 P sorbed (mg/kg) Conc. P calibrating solution (mg/L) P-isotherm Example of low level P sorption Calculated P sorption kg/ha =2100 standards 0 250 500 750 1000 1250 1500 1750 250 500 750 1000 1250 1500 P sorbed (mg/kg) Conc. P calibrating solution (mg/L) P-isotherm Example of high level P sorption Calculated P sorption kg/ha =9900 y = 256.96x - 900.96 R² = 0.9842 0 300 1.00 10.00 P sorbed (mg/kg) Log10 final supernatant concentration ug/L P-isotherm Example of low level P sorption y = 455.89x - 1351 R² = 0.9718 0 250 500 750 1000 1.00 10.00 P sorbed (mg/kg) Log10 final supernatant concentration ug/L P-isotherm Example of high level P sorption Calculations for P management in wastewater Lanfax Laboratories. Armidale 16th December 2016 Page 6 of 8 6. P in wastewater P, as the anion phosphate (PO43-), exists in several forms in wastewater. Inorganic phosphate from laundry detergents and household cleaning products: Orthophosphate, sometimes referred to as soluble reactive P (SRP); and the polyphosphates made up of chains of phosphates such as pyrophosphate and tri-polyphosphate (TPP). These polyphosphates are unstable in water and break down into orthophosphate. This contribution is about 85% of the household’s wastewater flow. Organic phosphate sourced from human excreta (faeces and urine) and food wastes (kitchen sink). Nearly all (80-100%) the phosphates in domestic raw wastewater are present in the effluent from septic tanks (Crites and Tchobanoglous 1998). The same applies to aerated wastewater treatment systems (AWTS) unless there is an active means of removing P, which in most cases, there is not. When plant removal, precipitation and P sorption are taken into account, it is possible to design a land application area that can minimise the risk of transport of P outside the buffers to the area. The most likely cause of P moving off-site is through hydraulic failure and surfacing of effluent from trenches, or failed irrigation systems connected to AWTS. Erosion of surface soils removes soil particles to which P is adsorbed as well as the P in organic matter. Because orthophosphate is an ion (an anion to be correct), it is free to move with the percolating effluent through all the soil pores – macropores and micropores. As the water carrying the ions passes P sorbing properties, the phosphate ion is attracted and rapidly immobilised (adsorbed). Thus, all of the wetted zone from the effluent has the potential to immobilise the phosphate, not just the zone around roots or macropores, but throughout the soil profile. 7. Uptake of phosphorus by plants How much P a plant will uptake from the soil is related to the type of plant, its vigour and the availability of P in the soil and other growing conditions such as plant available water (PAW), balance of other nutrients (N, K, S, Ca), as well as temperature and sunlight. Moody (2011) suggests that biologically available P consists of dissolved reactive P (DRP) as dissolved and colloidal organic and inorganic P, and bioavailable particulate P (BPP) as that which is immediately available to microorganisms. The methods used to determine these fractions are not in routine use in Australia even though these fractions are important to agriculture and environmental risk analysis. While single point P sorption index is applicable to growing crops it does not quantify the immobilisation of P in wastewater management. In Section 1, the uptake used for modelling purposes was 30 kg P/ha, a value commonly attributed to grasses growing under favourable conditions, that is, no limiting P concentration in the soil water, adequate nitrogen, adequate plant available water and favourable weather. Since the effluent application area is not usually water limited, and has a mixture of nitrogen, P, potassium and sulphur (although imbalanced), the growth of plants is more akin to irrigated agriculture. Perhaps the need to mow the effluent application area more often than non-effluent areas is a practical expression of the greater plant production expected. The NSW Guidelines (p.153) suggest 2-4 mg P/m2.day is the rate of plant uptake of P, equating to 4.3 – 14.6 kg P/ha, in the effluent application area. AS/NZS 1547:2012 does not provide any guidance on plant uptake of P, as if it is not a limiting factor to land application area assessment. DEC (2004) Table 4.2 (p. 42) tabulates the P removed in effluent irrigated kikuyu and perennial rye as 60 kg and 48 kg P/ha respectively, about 0.3-0.4% of dry matter. No data are available for a typical domestic effluent irrigation area, but both grasses are used in domestic lawn mixtures. The significant difference between the NSW Guidelines and DEC (2004) is not readily explained. The most important consideration is that the effluent disposal area (surface or sub-surface) is an irrigated pasture, not a rain-fed pasture, so comparisons of P loading rates with other effluent re-use projects is more reliable as to the performance of the land application area. Comparing the domestic irrigation with commercial piggery wastewater is not a reasonable road to take. The second important aspect is that P is an essential plant macro-nutrient and where water and other nutrients are not limited, greater vegetation mass will be produced. That’s why the production of vegetation with effluent will produce more grass than rain-fed areas, and uptake more P and other nutrients. Removing those cut grasses harvests the P for use in other areas, such as composting for garden use. Sergeant (2009) indicated that for the establishment of perennial pasture, an initial application rate of 20-30 kg P/ha was required at establishment and thereafter on an annual basis. The effluent application area needs to be considered a perennial pasture, with mowing replacing hungry mouths. To reverse-engineer the size of the effluent irrigation area, using the 0.3-0.4% P in grasses/pasture/lawns, then to remove the calculated P load in Calculation A1 (1.825 kg P), one has to remove 608 kg dried grass per year. When effluent reuse data show 20 t/ha grass production (APL 2010, Table 14.4), then 304 m2 of irrigation area is required, without accounting for any P sorption. When only the difference between half of the P sorption (2000 kg P/ha) is taken into account in Calculation A3, then 260 m2 of irrigation area is required to produce 520 kg grass. The question to ask is whether the effluent irrigation area can produce that mass of grass. Calculations for P management in wastewater Lanfax Laboratories. Armidale 16th December 2016 Page 7 of 8 8. Improving soil phosphorus sorption capacity When the soil in a land application area, whether for surface irrigation or sub-soil drainfields, has a low P sorption capacity a large area is required for assimilation of that P to minimise risk of loss off site. If the calculations in A2 and A3 were applied to Figures 1 and 2, then the required land application areas would be 253 m2 and 80 m2 respectively. Thus, the actual determination of P sorption is required to address the P assimilation. Amelioration of effluent for the surface soil for irrigation or the trench for sub-surface disposal is always an opportunity. Adding aluminium or iron to increase the P sorption will only make the soil very acid and impede plant nutrition and needs to be done with cation. Adding calcium in the form of agricultural lime (calcium carbonate) or gypsum (calcium sulphate) is preferred. Lime will slowly increase the pH of the soil (make more alkaline) but gypsum has almost no effect upon shifting pH. Application rates of up to 0.5 kg/m2 (5 tonne/ha) of lime/gypsum can be applied. For irrigation areas, the lime/gypsum is simply spread on the surface and allowed to wash into the soil. Holford (1983) showed that for acid soils, the addition of lime increased the exchangeable phosphate (plant nutrition) while also increasing sorptivity. He also showed that for very acid soils (pH<4.5), iron and aluminium increased phosphate precipitation and as pH increased with liming, the activity of the adsorption sites increased. When limed above pH 5.8 most soils tended to decrease in sorptivity and affinity without a corresponding decrease is sorption capacity. Thus, liming not only make P more available to the plants, it also prevents off-site losses through increased sorption capacity. For sub-surface discharges, lime or gypsum can be mixed into a watery slurry and funnelled into the outlet from the septic tank so that it moves into the drainfield. Other proprietary products such as superfine eco-floTM lime or eco-floTM gypsum are easier to handle than agricultural products. Regular dosing of lime and/or gypsum may improve the P sorption as well as the soil permeability while overcoming the effects of sodium in the effluent. There is nothing to prevent the occupants regularly dosing the superfine products through the toilet, where there will be benefits in the primary treatment system and in the land disposal area. Many soils in NSW have a high affinity for P sorption at rates of 15 000 kg/ha and above. Sourcing some of these soils for addition to sandy low P sorbing soils may be an opportunity. Blast furnace slag has excellent P sorbing properties and can be used as the gravel in drainfields or blended with soil below the surface soil. Transport costs may be a limiting factor. Mineral peat, an acidic blend of organic peat and natural minerals also provides high P sorbing capacity, sphagnum peat has no such properties. 9. Conclusion P, present in wastewater in the inorganic (orthophosphate, pyrophosphate and polyphosphate) and organic forms, varies according to the eating and laundry habits of the occupants of the household. While the concentration of P in the wastewater stream may vary, it is the load of P that needs to be judged. One simple solution to decreasing P concentration is to use more water for dilution, but that does not change the load. Unfortunately, the NSW Guidelines calculate the household’s contribution to its output of P by multiplying an average P concentration by the daily volume of water used. The problem is that for a normal four-person household on rainwater that equates to 1.83 kg P/yr, compared to 2.19 kg P/yr for a similar household on reticulated water. So from where does the extra P materialise? Does an average four-person household on tank water eat less than a similar household using reticulated water? Surely that’s not the depth of understanding by the authors of the Guidelines! The premise, in the Guidelines, that we have to discount the measured value of P sorption in a particular location by 50- 75% has no foundation. Since the phosphate ion moves with the percolating effluent, into macropores and micropores alike, it is farcical to assume that for whatever reason only 25-50% will be adsorbed without any evidence compared to the laboratory analysis of site specific soils. Discounting simply to be conservative is not a valid reason. While there are many analytical methods of assessing P sorption capacity, most are related to estimating the soluble P available for plant nutrition and the availability of P following application of superphosphate. Most methods do not relate to estimating the maximum P sorption capacity of an effluent application area. The calculations set out in Section 2 need to commence at choosing a reliable and consistent approach to determining the annual load of P from the household. Simply selecting an average P concentration of 10 mg P/L and multiplying by the daily water use has been shown to be nonsense because it assumed that the more water that is use the more P discharged. Therefore, calculation A1 simply needs to be the average daily P discharge per person calculated for the household for the year. The NZ household estimate of 2 kg P/year is probably a reasonable estimate given the similar current practice of using ‘NP’ and ‘P’ detergents in Australia and NZ. Certainly, where P sorption capacity is low, the household needs to be encouraged to favour a low P regime. The Guideline selection of a 50-year period for immobilising P is a thought bubble as even our consumption of P in laundry detergents has gone more than 8 g P/wash a decade ago to mostly ‘NP’ and ‘P’ products today. For new system designs we need to rely upon the realities of household P consumption, not the publications of last century. However, as Calculations for P management in wastewater Lanfax Laboratories. Armidale 16th December 2016 Page 8 of 8 an ultra-conservative approach, 50 years may be a suitable period, as used in the calculations above. In reality, unless we monitor the land application area, we will never know how the P sorption characteristic is functioning. P is an essential plant nutrient that has concerned agriculturalist for generations, specifically with securing a minimum available phosphate level in the soil for the growing around the crop. For wastewater management, it is not the limiting level of phosphate that is important, rather the capacity of the soil to bind P in the effluent from moving outside the land application area. Only through modifying the P sorption analysis are we able to determine that potential, hence an amended test regime, using elevated equilibrating solutions is required. Thus the particular components of the P budget include: Annual household generation of P – preferably load. Annual plant uptake of P from the land application area. Annual P sorption capacity of the soil in the land application area – based on 50-year life. Calculated land application area including required buffers. 10.References Alexander, GC. And Stevens RJ, 1976 Per capita P loading from domestic sewage Water Research Vol.10, Issue ( pp 757-764 accessed on 16 November 2016 from http://www.sciencedirect.com/science/article/pii/0043135476900932 Allen, D.G., Barrow, N.J. and Bolland, M.D.A., (2001) Comparing simple methods for measuring phosphate sorption in soils. In Aust. J.Soil Res., 39, 1433-1442. Australian and New Zealand Standard AS/NZS 1547:2012 On-site domestic wastewater management. Standards Australia, Sydney and Standards New Zealand, Wellington. Australian Pork Limited (2010) National Environmental Guidelines for Piggeries. Second Edition (Revised) Australian Pork Limited. Accessed 16 November 2016 from http://australianpork.com.au/wp-content/uploads/2013/10/National-Environmental-Guidelines-for-Piggeries.pdf Burkitt, L.L., Sale, P.W.G. and Gourley, C.J.P. (2008) Soil P buffering measures should not be adjusted for current P fertility. Aust. J. Soil Res., 2008, 46, 676-685. Crites, R., and Tchobanoglous,G. (1998) Small and Decentralized Wastewater Management Systems. San Francisco, CA: McGraw-Hill, Boston. DEC (2004) Environmental guidelines; Use of effluent by irrigation. NSW Dept Environment & Conservation, Sydney. DLG (1998) Environment and Health Protection Guidelines On-site Sewage Management for Single Households. Depart. Local Gov’t., NSW Environ. Protection Authority, NSW Health, Land & Water Conservation, and Dept Urban Affairs & Planning Sydney. DSITI (2015) Model for Effluent Disposal using Land Irrigation MEDLI V.2. Queensland Depart. Science, Information Technology and Innovation Dorahy, C., Harper, G. & Marczan, P. (2004) Using nutrient budgeting and environmental monitoring to assess the sustainability of effluent reuse from piggeries in New South Wales. In Proceedings of SuperSoil 2004. 3rd Australian New Zealand Soils Conference, 59 December 2004, University of Sydney. Published on CDROM. Environment Canterbury Regional Council (2012) Estimating nitrogen and P contributions to water from discharges that are consented and permitted activities under NRRP. Accessed 10 November 2016 from http://ecan.govt.nz/publications/Plans/selwyntewaihora-estimating-nitrogen-P-loads- 120712.pdf Gilmour, D., Blackwood, D, Comber, S. and Thornell, A. (2008) Identifying human waste contribution of P loads to domestic wastewater. In Proceedings 11th international Conference on Urban Drainage, Edinburgh Scotland. Accessed 20 November 2016 https://web.sbe.hw.ac.uk/staffprofiles/bdgsa/11th_International_Conference_on_Urban_Drainage_CD/ICUD08/pdfs/740.pdf Holford, I.C.R. (1983) Effects of lime on phosphate sorption characteristics, and exchangeable and soluble phosphate in fifteen acid soils. Aust. J. Soil Res., 1983, 21, 333-43 Kruger I, Taylor G, Ferrier M (eds) (1995) ‘Australian pig housing series: effluent at work’ (NSW Agriculture: Tamworth) referenced in DEC (2004) Environmental guidelines; Use of effluent by irrigation. NSW Dept Environment & Conservation, Sydney. Lusk, M., Toor,GS. and Obreza, T. (2015) Onsite Sewage Treatment and Disposal Systems: P. University Of Florida Accessed NOV, 2016 https://edis.ifas.ufl.edu/ss551 Moody, P.W. (2011) Environmental risk indicators for soil P status in Soil Research, 2011, 49, 247-252 Patterson, R.A (2001) P Sorption for On-site Wastewater Assessments in Proceedings of On-site ‘01 Conference: Advancing On-site Wastewater Systems by R.A. Patterson & M.J. Jones (Eds). Published by Lanfax Laboratories, Armidale ISBN 0- 9579438-0-6, pp 307-314 Rayment, G.E. and Lyons, D. J.( 2011) Soil Chemical Methods - Australasia. CSIRO Publishing. Canberra. Sargeant, K (2009) Perennial pasture establishment. Accessed 10 November 2016 at http://agriculture.vic.gov.au/agriculture/dairy/pasturesmanagement/perennial-pasture-establishment U.S. EPA. Onsite Wastewater Treatment Systems Manual. EPA/625/R-00/008, 2002. Accessed 20 November 2016 http://www.epa.gov/owm/septic/pubs/septic_2002_osdm_all.pdf.

The ratio should be 1%, ie 1gm detergent in upto 100 ml water

In my opinion, advanced oxidation process is the first recommended technology and incineration could be as an alternative.

For drinking water BOD has to be less than 5 mg/L and for treated wastewater to be disposed of in the water bodies it is 30 mg/L, 100 mg/L if treated waste water is discharged into the sewerage system

Good question....

Just for example, Fe(II) could be measure colorimetrically with o-phenanthroline and if you add ascorbic acid (reducing agent), you will get total Fe (Fe(II) + Fe(III)).

There may be no problem with your method at all. Sample handling is probably the biggest source of error in this type of work. You mentioned that the results change the most when you let time elapse. First chemical addition effects are often hard to fully measure because rates slow as concentrations slow. So that , even though an effluent is discharged it does not mean that reactions have stopped. By taking a sample and letting it set you are in comparison to the industrial process adding more retention time, but the effluent going out of the plant is not getting the benefit of this retention. Secondly, even though solids are small and not apparent settling occurs over time so that what you think is a representative sample (through put to the analytical equipmnet) is not. This is an especially important factor as solids content increases and is the source of very large errors throughout the waste treatment field when measuring influent as opposed to effluent. As an example my research shows that for normal municipal influents for many pollutants an error of as much as 20% occurs after only 2 or 3 seconds of not shaking a sample when splitting samples. My recommendation is to try to mimic the time as close to the actual conditions of the treatment system to capture what is going out in the discharge then follow this religously. Second examine your method to make sure after taking the sample at every step to make sure what enters your equipment is representative of the entire sample.

Hi.

1 - M (CH3COONa) = 82 g/mol; M(CH3COO-) = 59 g/mol, thus mass fraction of acetate in sodium acetate = 59/82 = 0.72

You have 204.9 mg/l of CH3COONa, thus C(CH3COO-)=0.72 x 204.9 = 147.5 mg/L.

2 - Not a microbiologist but have worked with many biological wastewater treatment systems, and I would say there's no reason why natural microbial communities would not use acetate as carbon source.

Cheers

Through the Advanced Oxidation Processing

Yes

I think ICP-MS

Interesting

Ion Chromatography will be the better option:

Refer following link for PDF (Page 15)

Harlan Glen Kelly Thanks for sharing your knowledge. On a research, it says that 'Putting defoamer on Nocardia film is like adding gasoline to fire. The Nocardia may retreat for 30 minutes, but the foaming will just come back worse '. And our plant uses the defoamer to get rid of Nocardia Filaments. That may cause to have high foaming at API tank and at Hydrotreater. The other chemicals that we use acid and Sodium Hydroxide.

If you take a look at the picture, waste water goes into Wet Well after that API tank, and after that to Centrifuge, after that Hydrotreater, and at hydrotreater if pH is in-spec, then it sends to City, if pH is out of spec, it recycles the waste to wet well. (Min pH spec is 6.00, max pH spec is 10.00)

2 days ago we cleaned entire treatment plant. It start foaming again today. API separator usually 96% full. The system capacity is 200gpm, and centrifuge feed flow rate usually at 140gpm, and bowl speed 2390rpm. There might be issue here, because the flow rate from wet well to API separator usually between 180-200 gpm, but centrifuge feed flow rate usually around 140-150gpm. What if we increase the centrifuge flow rate, would it help us to increase the separation and to reduce foaming?

I am trying to solve the problem but there might be other factors, like incorrect equipment usage.

Temperature effects on it too, but there is always foaming in this treatment plant.

You should use DB-5 column for chloro-phenols

The F:M ratio and the SRT which is directly related to F:M influence the settleability and compactibility of the sludge . When biomass is in the endogenous decay it tend to form polumers that result into natuyral floocculation . In the reactor low sludge ages the sludge tends to become populated with filamentous organisms that exhibit poor settleability and sludge does not flocculate well

In the system the settled sludge is returned from the clarifier to the aeration basin to maintain the desired food to microorganism ratio. The most accurate method of determining the returned sludge is based on SVI. The SVI test determines the settling behavior of MLSS. The high SVI in your plant showed that the sludge from a conventional aeration basin does not settle well and fills up the clarifiers.Low SVI is an indicative of sludge that settles well. Please maintain now the concentration of VSS and TSS in the mixed liquor to always getting low SVI.

The F:M ratio and the SRT which is directly related to F:M influence the settleability and compactibility of the sludge . When biomass is in the endogenous decay it tend to form polymers that result into natural floocculation . In the reactor low sludge ages the sludge tends to become populated with filamentous organisms that exhibit poor settleability and sludge does not flocculate well

At the other extreme of highly starved conditions or a very high SRT , the sludge forms needle floc and does not flocculate

The publication of AWWA for wastewater treatment are available. Simply bu following their norms, you can slowly benchmark the WWTP

In my opinion Ca(OH)2 is used as a coagulant but generally with low effectiveness. The main application of lime is alkalization of wastewater. The typical concentration as suspension in industrial wastewater plants is 10-15%

The question is not clear.

Detailed statement of the question is suggested.

Hello,

Washing with 80:20 (water:ACN) for 3 hours at 1ml/min and 80:20 for other 3 hours(ACN:water) works fine.

Otherwise there are more precise procedure (source: chromacademy)

Reversed phase columns include C30, C18, C8, C4, C1, CN and phenyl stationary phases. To clean and regenerate a reversed phase column flush it with the following volumes of solvent.

20 column volumes of water/acetonitrile (95:5 v/v)

20 column volumes of acetonitrile

5 column volumes isopropanol

20 column volumes hexane

5 column volumes isopropanol

20 column volumes acetonitrile

20 column volumes of water/acetonitrile (95:5 v/v)

Re-equilibrate with the required mobile phase

Be aware that in the case you are using phosphate buffer an overnight washing of the system (removing the column) with 100%water is required. This is done in order to prevent precipitation of salts

Regards

Check first the Standard Methods for Water and Wastewater analysis....then chosee.

Dear Soheil,

if you do not have an TOC analyzer you can use the titration method with potassium dichromate. I take the attitude that it will be a good method especially for cattle manure.

Following up on Mr. Mambo's suggestion, the post ethanol process waste can be mixed with the bagassee to make protein for animal feed.

The quantity of samples depends on the methods used and organic load for the quantification of BOD. For eg. if selecting Wrinkler's method (APHA), you need at least 2 L for water having low COD. If the COD is high, you need less amount of water.

If you would like to do the BOD analysis by LDO probe or respiration method, 500-600ml sample will be sufficient.

I would advise you to first check the COD and according make dilutions for BOD. Generally BOD is around 45-60% of COD.

Thank you

yes I already worked with it is a method based on complexometry the results very reliable and repetitive only for the calibration curve, I advise you to build one with a spectrophotometer of typen Shimadzu as the comparator provided

The biomass growth is the first reason. Second thing is the characteristics of the compounds in the water. Some of them, at their primary form, can be non-degradable at BOD and COD measurement condtions. The the activated sludge converts them to other compounds, which can be oxidized during BOD or COD measurement.

The question is if the same bacteria are used in activated sludge and BOD.

It's effect of dose at constant pH, time, stirring rate.

I mean study the effect of pH at different times in the same experiment pH 5 at time 10, 15, 20 min and 100, 200, 300 RPM

I suggest it is well known that ammonia strip from water and it is in pH dependant equilibrium with ammonium. Therefor some loss can be expected depending on the pH.

Biarbonate and nitrate are ionic so they don't evaporate.

Any loss of COD depends on the organic matter that constitute the COD. If it is large and/or ionic molecules it will not evaporate. If some of the COD comes from small molecules such as volatile organic acids(VFA), ethanol some evaporation can be expected.

And now the newest one is Sumo...

If you want to measure bioactivity in-situ, i.e. with disrupting the biomass, one can drop a DO probe into the bioreactor, turn off the air supply and measure the DO as it decreases over about 5 minutes. This Oxygen Uptake Rate (mg O2/L-hr) is a direct indication of bioactivity - but can be influenced by when feed is delivered. After feeding, OUR can increase if bioactivity is feed-limited.

you just have to dilute your samples by 5 or 10 and after reading you multiply the value read by 5 or 10 to find the real value In this way the OD will be less than 2 and the good will be good

Which pore size you use is dependant both on which fraction of particular matter that you are searching and which country you  are in.

One recognised approach is that you use two different pore sizes l. 1.5 um is used to find the particular fraction. And you pass a flocculated sample through 0.45 um. What goes trough is soluble and the difference between what is retained on the 1.5 um and the 0.45 um is the colloid fraction. The fact that the sample is flocculated assure that also small free swimming bacteria is retained.

Formulas are correct. But second formula shows how many % of total solids are volatile. Sometimes people use other formula, which shows how many % of sample are volatile solids. 

Volatile Solids (%)= [(wt of dried residue & dish- wt of residue and dish after ignition)/ (wt of wet sample & dish- wt of a dish)]*100

The standard technique for data below the detectable limit is to assign them the mid-point value, so if the value is < 0.05 mg/l you assign it a value of 0.025 for assessing removals. If both inlet and outlet are below the detectable limit then I would suggest that you set the removal as 'not applicable'. All you can say is that the removal is somewhere between 0 and 100%.

Dear Nitish,

as already mentioned above only a small fraction of (ML)VSS will be nitrifiers/denitrifiers. Anyway, if you are just searching for an alternative method to estimate your biomass in activated sludge (since MLVSS measurement requires some time and sample volume), the following rough rules of thumb (!) so far seemed pretty reliable to me:

1) Carbon content in bacterial cells: 50% (dry weight)

2) MLVSS = 0.8 x MLSS

Therefore, if you measure the TOC (for example Hach Cuvette Test):

3) TOC x 2 = MLVSS

4) TOC x 2.5 = MLSS

Only applicable, if your DOC (dissolved organic carbon) is neglectable in comparison to biomass, otherwise you would have to subtract the DOC.

Be careful to shred your sludge flocks, and don't use pipette tips with narrow openings to avoid sludge separation by pipetting.

It is a bit odd that you don't mention the nitrification in the treatment. Mostly sewage treatment plants nitrify ammonia.

If there is no nitrification capacity in the plant most municipal sewage treatment plants have a diurnal rhythm in the ammonia concentration. Usually there is a peak in concentrations late in the morning and and smaller peak with longer duration in the evening and quite low concentrations during the day. Thus if you sample in the middle of the day you might have the effect of the morning peak towards the end of the plant and a low influent concentration. Likely the retention time of your sewage treatment plants is less than 6 h because it appears not to be able to nitrify.

You might also have ammonification which produces ammonia from hydrolysis of organic nitrogen (TKN).

It is not possible that ammonia stratifies. This can only happen to particles and molecules that doesn't completely dissolve.

the only concept that can be applied is to follow the standard techniques of carry out geophysical surveyor, this will enable you to determine the aquifer thickness, after the drilling  using the report , before the construction of the water bore hole, you must do your down hole logging, this will enable you to determine the contaminant zone, and you applied cement droughting  techniques to prevent the contaminant intrusion into the phreatic aquifers.

However, please keep in mind that for the BOD test, the field DO value is not needed.  Instead, you want to know the DO (usually after bringing it to 20 C and aerating the dilution water or even the sample to get it above 8 mg/L) immediately before sealing the BOD bottle for the 5 day incubation period. Best of luck with your work!

i think yes

Dear Dr Jorge

Probably as dear Dr Marcos mentioned:

[Residual water usually has a high organic matter concentrations. Aerobic respiration of these OM by bacteria could generate carbon dioxide that combined with water forming carbonic acid, decreasing pH in the sample. ]. It has been happened some times for me and we found out the H2CO3 ( which is not stable itself) is the major reason.

Best regards, Parisa Ziarati

One of the most common methods is to asses the COD / BOD of the wastewater (Stott 1997). The ratio of COD to BOD can give an indication of biodegradability of a wastewater as shown below:

A)        In domestic sewage which is known be readily biodegradable, the COD/BOD ratio varies typically from 1.5:1, thus if COD/ BOD ratio of industrial wastewater is also <2, this provides a good indication that the wastewater can be treated biologically

B)        If COD/ BOD ratio is high and generally >5:1 this indicates that the wastewater is non-biodegradable, toxicity or nutrient imbalance is present and, thus will present problems if biological treatment is selected

c)  If COD/ BOD falls between 2-5:1 then this is a grey area. A lot of industrial wastewater falls into this category

Dear Dipam,

Suggested process indicators apply to mesophilic digestion (28°C to 42°C).  Maintaining a temperature around 35°C and efficient mixing are the two main success factors.

Total VFA can be determined by distillation and titration.  Individual VFA are best determined by gas chromatography (see Standard Methods).  Can't say whether HPLC can be used though I think it can. 

Another parameter is hydrogen in the sludge gas which should be <100ppm.

Regards

Michael Lever

hope this paper could help you ,

regards

Chemical oxygen demand (COD) relies on chemical oxidation with chromic acid (a strong oxidizer). Many organic compounds, including color bodies and fibers, which are not easily biodegradable, along with any inorganic chemicals will show up as chemical oxygen demand but not biochemical oxygen demand (BOD). Some mills have found that filtered COD samples give a better surrogate for the five-day BOD test than the one-day BOD test.       Chemical oxygen demand (COD) is the amount of a specified oxidant that reacts with the sample under controlled conditions. Results are defined as the mg of Oâ‚‚ consumed per liter of sample. The sample is heated for two hours with a strong oxidizing agent, potassium dichromate. Oxidizable organic compounds react reducing the dichromate ion to the green chromic ion. The amount of Crâºâ¶ or Cr⺠³ is measured colorimetrically with a spectrophotometer. Chemical oxygen demand can be used to estimate biochemical oxygen demand (BOD≈ ½ COD) and determine the dilutions needed for the BOD five-day test.

Total COD is run on undiluted samples. For a soluble COD, the samples are filtered through a 0.45 mm filter before analysis to remove biological interference. 2 mL of the sample is pipetted into a COD digestion reagent vial. The vial is then inverted several times to mix (vial will get hot). The vial is placed in the COD reactor at 150 ° C for two hours. The samples then cool and the samples are tested using a spectrophotometer. The chemical oxygen demand value will be read in mg/L for both total COD (tCOD) and soluble COD (sCOD).

For samples with a concentration of 0 to 150 mg/L, use the low range COD vials. For higher concentrations the high range COD vials (0-1500 mg/L) should be used. If the COD exceeds 1500 mg/L, the sample should be diluted to bring the results in range.

Chloride is the primary interference.   Vials with mercuric sulfate can be used to eliminate chloride interference up to 2000 mg/L Cl–. Samples with higher chloride concentrations should be diluted enough to reduce the chloride concentration below this limit. If the sample is diluted the values are adjusted based on the dilution factor. If the COD testing is for permit reporting, the method including vials with mercury is the EPA approved method.

Colorimetric Determination of Ammonium (NH4+) in Solution

(ver. 960129)

There are several colorimetric methods available for determining NH4+ concentrations in water samples, soil extracts and plant digests. These methods all detect both NH4+ and NH3 forms of N. The method we will use is called "the indophenol blue method" or "phenate method." It is based on the reaction of NH3 in alkaline solution with phenate to produce a blue color (indophenol blue) in the presence of a strong oxidizing agent, such as hypochlorite. Although the reaction will proceed at room temperature, it can be sped up by heating the solution (35oC) and/or using a metal-containing catalyst such as sodium nitroferricyanide (nitroprusside). Many modifications of this method are available. The one we will use is based on Solorzano (Limnol Oceanogr. 1969. 14:799-801), modified for a 10 ml sample volume.

Other modifications of this method can be found in Methods of Soil Analysis (Page et al., eds., American Society of Agronomy, Inc. and Soil Science Society of America, Inc., Madison, WI), Methods of Seawater Analysis (Verlag Chemie; not in our library and may be hard to find) and Standard Methods for the Examination of Water and Wastewater. (Clesceri et al., eds., American Public Health Association, Washington, DC).

The phenate method also has been adapted for use on various automated analyzers, such as those manufactured by Technicon, Alpkem and Lachat. See the manual for the specific machine you are using.

Notes:

Use test tubes which can accommodate a 10 ml sample. All glassware should be very clean (scrubbed with hot water, rinsed with 0.1N HCL, rinsed 6 times with purified water, and rinsed once with reagent grade deionized water). Be sure water for reagents and standards is ammonia free. Ordinary distilled water may contain ammonium- use freshly deionized water.

Ammonia is volatile and is present in the air. Many different sources of ammonia can contaminate the samples. Smoking, ammonia detergents, freshly cut grass, opening a bottle of ammonium hydroxide in the laboratory, etc. Exercise caution.

Very turbid sample may need to filtered or centrifuged prior to analysis. Precipitation of calcium and magnesium hydroxide can interfere with the analysis. This can be prevented by addition of a complexing reagent such as citrate or EDTA. See Methods of Soil Analysis for further details (Page, A.L., R.H. Miller and D.R. Keeney, eds. 1982. Methods of Soil Analysis. American Society of Agronomy, Inc., Madison, WI)

Stock Reagents:

1) Phenol-alcohol reagent: dissolve add 10 g of phenol in 95% ethyl alcohol to a final volume of 100 ml (toxic- handle with care).

2) Sodium nitroprusside (nitroferricyanide): dissolve 1 g in DI water to a final volume of 200 ml. Store in dark bottle for not more than 1 month. (toxic)

3) Alkaline complexing reagent: dissolve 100 g of trisodium citrate and 5 g of sodium hydroxide in DI water to a final volume of 500 ml.

4) Sodium hypochlorite: use commercial bleach (i.e., Chlorox), as new as possible.

5) Oxidizing solution: add 100 ml alkaline solution (3) to 25 ml sodium hypochlorite (4). Prepare fresh daily.

Calibrants:

Stock Solution A- 1000 ppm NH4-N stock. Dissolve 4.7168 g of dry (110oC for 12 h) (NH4)2SO4 in approximately 900 ml of DI water in a 1 L volummetric flask. Bring to 1 L with DI water. Can be preserved by adding two drops of chloroform. Label with the solution, the date and your initials.

Stock Solution B- 100 ppm NH4-N stock. Transfer 10 ml of Stock solution A to a 100 ml volummetric flask. Dilute to mark with DI water. Label with the solution, the date and your initials.

Working standards (can be adjusted to cover the range of samples being analyzed). Using 100 ml volummetric flasks, prepare the following series of working standards.

Volume of Stock B Vol. of standard Concentration

1 ml 100 ml 1000 µg NH4-N/L

750 µl 100 ml 750 µg NH4-N/L

500 ml 100 ml 500 µg NH4-N/L

200 ml 100 ml 200 µg NH4-N/L

100 ml 100 ml 100 µg NH4-N/L

50 ml 100 ml 50 µg NH4-N/L

0 ml 100 ml 0 µg NH4-N/L

Assay:

1. Add 10 ml of standard or sample to labeled test tubes.

2. To all tubes add 0.4 ml (400 µl) of phenol solution (1), 0.4 ml nitroferricyanide (2) and 1 ml oxidizing reagent (5). (Note- volumes can be adjusted according to sample size)

3. Mix well (invert screw cap tubes). Let develop for at least 1 h (3 h is better) in darkness. Mix samples periodically while development is occurring.

4. Read absorbance of standards and unknown samples using a spectrophotometer set to 630 nm.

5. Use absorbance values of standards to generate a standard curve. Calculate concentrations in unknowns from standard curve.

6. Dispose of all assay waste into a labeled bottle -DO NOT PUT PHENOL DOWN THE SINK!

Limitations:

The detection limit is reported to be about 10 µg NH4-N/L and Beer's law is obeyed up to about 500 µg NH4-N/L. We have found that the method is linear to at least 750 µg NH4-N/L, and Koroleff (1976) reports that higher concentrations, up to 1200 µg NH4-N/L, can be measured with a one cm flow cell and an appropriate standard curve.

Sample preparation and storage:

Turbid samples and soil extracts will need to be filtered or centrifuged prior to analysis. If filtration is used, beware of ammonium contaminated filters (Whatman 42 is not acceptable). We have had success with Poretics polycarbonate membrane filters (0.4 µ pore size).

Samples should be stored in glass or polyethylene, and kept refrigerated until analyzed. Ammonium is very labile and samples should be analyzed as soon as possible (preferably within 7 days). Do not freeze samples before analysis. If necessary, samples may be preserved by addition of 0.8 ml conc. H2SO4 to pH<2 and then refrigerated. However, samples must then be neutralized before analysis, and contamination by absorption of atmospheric NH3 may be a problem..

Samples with concentrations above the high standard should be diluted with DI water (or other appropriate matrix, depending on the nature of the samples) before addition of reagents.

References:

Koroleff, F. 1976. Determination of ammonia. In Methods of Seawater Analysis (K. Grasshoft, ed.). Verlag Chemie, pp. 126-133.

BIOL 826 - Spring 1997

Lab Report #1

The first lab report will cover the first three weeks of labs, and will be about colorimetric analysis of solution samples for phosphate, ammonium and nitrate. It will not be due until the week after we complete all three labs (due February 18). Keep track of your data from these three labs. Specifically, you will need:

1. records of the concentrations and absorbances of your standards and samples.

2. a graphic presentation of your standard curve for each analysis.

3. the regression equations relating absorbance to concentration.

4. calculated results for your unknowns.

5. descriptions of methodology, including any modifications to the procedures, or problems encountered.

Normally a brownish colour will remain unless your treatment plant is designed to remove the Non-biodegradable Humic Acids normally being responsible for this colour. This will be the case if your effluent demand for COD will be < 50 mg COD/l.  This mean also that if you effluent limit is higher  i.e 200 mg COD/l you will have to accept that some colouring is there. The colour in it self can not be said to be direct harmful as long as you do not Chlorinate your effluent. Since Humic Acids are only extremely slowly degradable in nature the COD coupled to this colour will not result in any Oxygen uptake and hence no direct impact on the stream where the water enters. But if the water is chlorinate before discharge there will be potetial formation of  chlorinated organic compound  and these has a potential to be harmful. 

Hi

For large water volumes you may use a commercial NPK fertilizer and a cheap carbon source as ethanol or methanol.

Good work