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Numerical Analysis of the Incineration of Polychlorinated Biphenyl Wastes in Rotary Kilns

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... Previous research work (Bani-Hani and El Haj Assad, 2017;Bani-Hani et al., 2015) showed that the suggested mechanism of PCBs incineration can be generally expressed using the chemical reaction as shown in Equation (1). *Corresponding author 29-n C 12 H 1 o-nCln + 2 0 2 ~ 12C0 2 + (5n)H 2 0 + n HCL (1) The research showed that the incineration of PCBs in the rotary kiln incinerator is a safe disposal method, which leads to a stream of exhaust gases at 1200 K (Bani-Hani et al., 2016). This high temperature is an indication of high energy storage that can be utilized. ...
... This information depends on many parameters such as composition of PCBs burned, fuel composition and amount, amount of excess air used, and operating temperature and pressure. According to research done before (Bani-Hani et al., 2015;Bani-Bani et al., 2016;Rovaglio et al., 1998), the conservation law of energy may be expressed by Equation (12) ...
... through (15) and other parameters/ equations obtained from the previous work done by the researchers(Bani-Hani et al., 2015;Bani-Hani et al., 2016). ...
Safe disposal of some hazardous substances requires incineration at elevated temperatures. High temperature incineration prevents the formation of another type of hazardous substance in gaseous phase. This work focuses on the utilization of the energy stored in the gaseous effluents from the rotary kiln incinerators when combusting the polychlorinated biphenyls (PCBs) hazardous wastes. The incineration process with a heat recovery unit and a steam power plant as one unit is simulated using MATHCAD software. Results show that by using two heat exchanger units, shell-and-tube and cross-flow heat exchanger, the overall efficiency of the steam power plant is improved by 10%. A significant fuel savings value is also reported.
... PCBs classified as persistent organic pollutants (POPs) that retard the biodegradation process and stayed for long time in the environment. PCBs contain 1 to 10 chlorine atoms attached to biphenyl and a general chemical formula of C 12 H 10 -xCl x most PCBs were manufactured as cooling and insulating fluids for industrial transformers and capacitors stabilizing additives in flexible PVC coatings of electrical wiring and electronic components [3]. ...
... In previous work [3], studied the incineration process of PCBs wastes in a rotary kiln by a dynamic model consisted of a set of nonlinear equations comes from applying material and energy balances under unsteady state conditions. In another study [9] showed the model of PCBs incineration and validation. ...
... Finally, the results are presented and discussed. Equation 4 which is derived by Bani-Hani et al [3] shows the energy change E with process parameters such as temperature T, mass M, time t, and heat capacities C v . 4 ...
... PCBs classified as persistent organic pollutants (POPs) that retard the biodegradation process and stayed for long time in the environment. PCBs contain 1 to 10 chlorine atoms attached to biphenyl and a general chemical formula of C 12 H 10 -xCl x most PCBs were manufactured as cooling and insulating fluids for industrial transformers and capacitors stabilizing additives in flexible PVC coatings of electrical wiring and electronic components [3]. ...
... In previous work [3], studied the incineration process of PCBs wastes in a rotary kiln by a dynamic model consisted of a set of nonlinear equations comes from applying material and energy balances under unsteady state conditions. In another study [9] showed the model of PCBs incineration and validation. ...
... Finally, the results are presented and discussed. Equation 4 which is derived by Bani-Hani et al [3] shows the energy change E with process parameters such as temperature T, mass M, time t, and heat capacities C v . 4 ...
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The aim of this work is to have a review of some products where halogens are used in the manufacturing process along with the safe disposal methods of its wastes. Different halogenated compounds are introduced. The theoretical results are validated by comparing them with experimental results. Results show that incineration is a safe disposal method of polychlorinated Biphenyls (PCBs). The incineration of PCBs in rotary kiln is shown based on theoretical and experimental studies. Where energy and material balances are applied to rotary kiln incineration to derive the theoretical model. The results from the theoretical model is validated against experimental results. The disposal method by incineration for other halogenated compounds is presented. Different models representing the combustion of other halogenated components are analyzed. It is shown that incineration is the safe disposal method for halogenated compounds at temperatures around 1200 K to avoid the formation of toxic gas emissions like furan and dioxin. The theoretical results are comparable with the experimental data of the incineration process.
... 11 Literature shows that temperature around 1000 C must be reached in the incineration of polychlorinated biphenyl wastes to ensure no dioxins and furan formation in the product stream where they are classified as very harmful components for the environment. 12 The amount of excess air and the composition of natural gas fuel affect the value of AFT. The AFT has a higher value when oxygen is used compared to the value in case of using air for combustion. ...
... This fact is attributed to the presence of nitrogen N 2 ð Þ the energy scavenger which is an inert substance that does not participate in the combustion process; however, it absorbs the heat of combustion and releases it to the environment. 12 The same effect of reducing the AFT is observed when poor insulation is applied to the combustion chamber. 13 In addition to the existence of excess air, the composition of the fuel or natural gas determines the AFT. ...
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The combustion of natural gas consisted of methane CH4, ethane C2H6, and propane C3H8 is theoretically investigated to obtain the optimum adiabatic flame temperature (AFT). The investigation includes the development of combustion equations that take into consideration different compositions of natural gas. The final equation to calculate the AFT is derived and used in the optimization study. The optimization study using genetic algorithm investigates the effect of changing the composition of the gas mixture, the inlet temperature of used air, and the amount of excess air used on the AFT. It is possible to get the required composition of each component, the air inlet temperature, and the excess air by reading the chart to get the required AFT. The heat capacity of all reactants and products is used as a function of temperature. Results showed that the optimum values for CH4,C2H6,C3H8, percentages in the gas mixture, air inlet temperature, and the amount of excess air are 0.478, 0.166, 0.356 mol %, 1.848, 382.104 K, respectively. These optimum values lead to a value of about 1300 K for the AFT. The derived equation shows the AFT at different natural gas compositions along with different process parameters such as the amount of excess air. Thus, the required combustion temperature can be controlled by adjusting the natural gas composition or the combustion temperature can be specified based on the provided composition of the natural gas stream by using either the derived equations or output chart. (R1. 1).
... A numerical analysis of polychlorinated-biphenyl waste treatment within an RK using the MATLAB routine is presented by Bani-Hani et al. [54]. A dynamic model simulates the mass, energy, and concentration of species during combustion. ...
... The model can simulate different process conditions in the rotary kiln for different waste compositions. According to the simulation results, the authors recommend optimal operating conditions for polychlorinated-biphenyl waste incineration [54]. ...
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A rotary kiln is a unique facility with widespread applications not only in the process industry, such as building-material production, but also in the energy sector. There is a lack of a more comprehensive review of this facility and its perspectives in the literature. This paper gives a semi-systematic review of current research. Main trends and solutions close to commercial applications are found and evaluated. The overlap between process and energy engineering brings the opportunity to find various uncommon applications. An example is a biogas plant digestate treatment using pyrolysis in the rotary kiln. Artificial intelligence also finds its role in rotary kiln control processes. The most significant trend within rotary kiln research is the waste-to-energy approach in terms of various waste utilization within the process industry or waste pyrolysis in terms of new alternative fuel production and material utilization. Results from this review could open new perspectives for further research, which should be focused on integrated solutions using a process approach. New, complex solutions consider both the operational (mass calculations) and the energy aspects (energy calculations) of the integration as a basis for the energy sustainability and low environmental impact of rotary kilns within industrial processes.
... This is a very important issue for the operation of hazardous waste incineration plants. The huge diversification of waste and its inappropriate selection for loading may cause operational problems, breakdowns, and instability of the thermal process, limiting energy recovery from waste, as well as temporarily exceeding the permissible emission standards of harmful gases into the atmosphere [11][12][13]. ...
... A similar problem was not encountered during the literature review. Ref. [13], which contained the general principles of conducting the process in a waste incineration plant, turned out to be the closest to this issue. The reason for the insignificant number of references may be the practical approach to the problem. ...
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Recovering energy from waste is a positive element in the operation of a waste incineration plant. Hazardous waste is a very diverse group, including in terms of its fuel properties. Carrying out the thermal process in this case is associated with the difficulty in maintaining stable conditions. This may translate into the efficiency of energy recovery from waste. The article presents a tool supporting the work of hazardous waste incineration plant operators, the aim of which is to select waste for a batch of input material in a manner that ensures process stability and efficient energy recovery. The tool is an application in which the bee algorithm is implemented. It selects the optimal solution to the problem, in accordance with the assumed parameters. The application tests in laboratory conditions were satisfactory and indicated compliance with the assumptions and stability of the solution.
... International conventions state regulations to protect the environment and are setting tighter restrictions on industries to achieve higher standards for more environmental friendly products. Hence, the problem of coexistence of sustainable industry and safe environment are among challenges for most industrialized countries in the scene of fuel prices and availability (Bani-Hani, et al., 2016). The traditional means to manage the municipal wastes in developing world is direct dumping and land filling (Menikpura, et al., 2016). ...
... The traditional means to manage the municipal wastes in developing world is direct dumping and land filling (Menikpura, et al., 2016). Other municipalities and large industrial plants are applying Rotary-kiln incinerator as a method of safe disposal of hazardous wastes (Bani-Hani, et al., 2016). ...
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The aim of the current work is to provide an overview of the agricultural wastes– biomass wastes, such as corn stalks, straw, nutshells, and forestry residues applications in different industries to sustain the environment. Literature showed that millions-Ton update estimates potential supplies of agricultural crop residues and wastes. The largest quantities of agricultural residues and wastes are from the major commodity crops. In the past years (on yearly average) there was approximately a million ton of primary dry crop residues that can be utilized, and sometimes make a profit by collecting them at farm gate with feedstock prices of 60 and 50 US Dollars per dry ton. The literature showed also many applications of biomass wastes which are considered as renewable and safe source for many industries such as manufacturing cementitious bricks by direct use or by direct incineration to produce energy, and by using the ash results from the combustion in the concrete matrix, producing energy and power through direct combustion or by producing bio fuel that can be utilized later, using in the water and waste water treatment as adsorbent, fertilizers, animal feed stocks, and extracting industrial chemicals for huge and important application like corrosion inhibitors.
... International conventions state regulations to protect the environment and are setting tighter restrictions on industries to achieve higher standards for more environmental friendly products. Hence, the problem of coexistence of sustainable industry and safe environment are among challenges for most industrialized countries in the scene of fuel prices and availability (Bani-Hani, et al., 2016). The traditional means to manage the municipal wastes in developing world is direct dumping and land filling (Menikpura, et al., 2016). ...
... The traditional means to manage the municipal wastes in developing world is direct dumping and land filling (Menikpura, et al., 2016). Other municipalities and large industrial plants are applying Rotary-kiln incinerator as a method of safe disposal of hazardous wastes (Bani-Hani, et al., 2016). ...
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The aim of the current work is to provide an overview of the agricultural wastes– biomass wastes, such as corn stalks, straw, nutshells, and forestry residues applications in different industries to sustain the environment. Literature showed that millions-Ton update estimates potential supplies of agricultural crop residues and wastes. The largest quantities of agricultural residues and wastes are from the major commodity crops. In the past years (on yearly average) there was approximately a million ton of primary dry crop residues that can be utilized, and sometimes make a profit by collecting them at farm gate with feedstock prices of 60 and 50 US Dollars per dry ton. The literature showed also many applications of biomass wastes which are considered as renewable and safe source for many industries such as manufacturing cementitious bricks by direct use or by direct incineration to produce energy, and by using the ash results from the combustion in the concrete matrix, producing energy and power through direct combustion or by producing bio fuel that can be utilized later, using in the water and waste water treatment as adsorbent, fertilizers, animal feed stocks, and extracting industrial chemicals for huge and important application like corrosion inhibitors.
... Chlorinated biphenyls have been produced in large quantities from the 1930s to the 1990s, and due to their unique physical, chemical and electrical properties, they are widely used as dielectrics in capacitors, hydraulic fluids in hydraulic tools, transformer oil, materials Surface coating, adhesives, pesticides, carbonless copy papers, inks, waxes and paints are used in the industry [13][14][15]. Monochlorobiphenyl is one of the polychlorinated biphenyl (PCBs) components that cause several effects on environmental components, and its safe disposal requires careful design [31]. The incineration of wastes, in general, and hazardous wastes can be used as an alternative fuel. ...
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the full length paper can be viewed for limited time at [https://www.sciencedirect.com/science/article/abs/pii/S0360544223012550?fr=RR-2&ref=pdf_download&rr=7cc2cb7c4b740da1] This paper develops a thermodynamic model for the regenerative Brayton cycle that uses monochlorobiphenyl waste as fuel in a combustion chamber to power a gas turbine. The regenerator increases the air temperature entering the combustion chamber to react with monochlorobiphenyl wastes to produce a higher turbine inlet temperature. The pressure ratio and turbine inlet temperature can negatively or positively affect power plants' thermal efficiency. Thus, different pressure ratios and turbine inlet temperatures are used to calculate the overall thermal efficiency. A stoichiometric reaction-based gas composition model is used to determine the combustion gas composition at the combustion chamber exit and to calculate the heat capacity of air and combustion gases as a function of temperature. The exergy analysis of the proposed power plant is presented to determine the effect of the pressure ratio on the exergy efficiency of the turbine, compressor, and regenerator. According to the results, an increase in pressure ratio increases cycle thermal efficiency and turbine inlet temperature when using a regenerator, whereas the temperatures decrease when not using a regenerator. The Brayton cycle with a regenerator increases thermal efficiency from 30% to 100% for a pressure ratio of 6–30. This contrasts with the Brayton cycle without a regenerator. In addition, for the regenerative Brayton cycle, the turbine inlet temperature rises from 1050 K to 1200 K as the pressure ratio rises from 1 to 30. In the absence of the regenerator, however, this variation's trend is in the opposite direction. Furthermore, the results show that an increase in pressure ratio will increase the exergy efficiency of the compressor and regenerator, while a decrease will occur in the exergy efficiency of the turbine. Findings indicate that the regenerator has the highest exergy efficiency at a pressure ratio higher than five, followed by turbine and compressor exergy
... In fact, increasing the radius will increase the fluid flow thus the required length is decreased to heat the room. To calculate the mass flow rate a Remoulds number (Re) of 2300 is used, where (ri) is the inner radius of the pipe, and (µ) is the viscosity [16,17]. ...
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Thriving towards renewable energy is an optimum process to mitigate environmental problems such as climate change. Any source of energy that is harnessed from renewable resources is considered as a green source of energy. These referred sources are naturally replenished within human’s timescale such as rain, wind and sunlight. This research aims to investigate experimentally the utilization of solar energy in heating systems. Two systems were investigated; water to water (WTW) system and water to oil (WTO) system, which uses thermal oil to transfer heat to water. A feasibility study has been conducted to evaluate the two systems in order to investigate which one is the most optimal solution. Based on the performed calculations, it was found that WTO method is more efficient in terms of producing sufficient heat and reducing piping material, the length of the pipes has decreased from 78.78 to 7.13 meter when switched from WTW to WTO method.
... In fact, increasing the radius will increase the fluid flow thus the required length is decreased to heat the room. To calculate the mass flow rate a Remoulds number (Re) of 2300 is used, where (ri) is the inner radius of the pipe, and (µ) is the viscosity [16,17]. ...
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Thriving towards renewable energy is an optimum process to mitigate environmental problems such as climate change. Any source of energy that is harnessed from renewable resources is considered as a green source of energy. These referred sources are naturally replenished within human’s timescale such as rain, wind and sunlight. This research aims to investigate experimentally the utilization of solar energy in heating systems. Two systems were investigated; water to water (WTW) system and water to oil (WTO) system, which uses thermal oil to transfer heat to water. A feasibility study has been conducted to evaluate the two systems in order to investigate which one is the most optimal solution. Based on the performed calculations, it was found that WTO method is more efficient in terms of producing sufficient heat and reducing piping material, the length of the pipes has decreased from 78.78 to 7.13 meter when switched from WTW to WTO method.
... In fact, increasing the radius will increase the fluid flow thus the required length is decreased to heat the room. To calculate the mass flow rate a Remoulds number (Re) of 2300 is used, where (ri) is the inner radius of the pipe, and (µ) is the viscosity [16,17]. ...
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Full-text available
Thriving towards renewable energy is an optimum process to mitigate environmental problems such as climate change. Any source of energy that is harnessed from renewable resources is considered as a green source of energy. These referred sources are naturally replenished within human’s timescale such as rain, wind and sunlight. This research aims to investigate experimentally the utilization of solar energy in heating systems. Two systems were investigated; water to water (WTW) system and water to oil (WTO) system, which uses thermal oil to transfer heat to water. A feasibility study has been conducted to evaluate the two systems in order to investigate which one is the most optimal solution. Based on the performed calculations, it was found that WTO method is more efficient in terms of producing sufficient heat and reducing piping material, the length of the pipes has decreased from 78.78 to 7.13 meter when switched from WTW to WTO method.
... The commonly accepted explanation for this practice is that it helps to evaporate the moisture in the fuel and to increase the overall thermal efficiency of the boiler. It is also widely believed that with regards to the combustion of packed beds, ignition is influenced by the radiation from the high-temperature flue gas and walls, it takes place on top of the waste layer, narrow in proportion to the bed height and propagates downward along with the bed pile [14][15][16][17][18][19]. Thunman and Leckner demonstrated, from the measurements of combustion in a grate boiler with the primary air preheated to 150 • C, that the reaction layer on the surface of the fuel bed has a slower propagation speed for fuel that has higher moisture content. ...
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... On the other side, heterogeneous feedstock and inappropriate separation seems to result in fluctuant heating value and equipment corrosion [26]. Some advanced technologies are essential to clean combustion such as oxyenrichment incineration [26], rotary kilns incineration [27] and in-situ inhibition of dioxins [24], raising the cost of plastic energy recycling. Therefore, a mature separation technology is urgently needed for energy recycling of plastic. ...
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Throughout the world, sites have been discovered which contain hazardous wastes. To completely destroy the contaminants in the soil, incineration remains the primary option for soils containing organics with high boiling points. This paper deals with operational aspects of the Transportable Incineration System, including specific procedures which were developed during the incineration of PCB-contaminated soils at the Lauder salvage yard in Beardstown, Illinois. Some of the issues treated in this paper include:•• Prescreening of soil to remove oversize materials.•• Process description.•• Treated soil material handling at elevated temperatures.•• Slag formation in the kiln and secondary combustion chamber.•• Development of procedures required for trial burn testing. Some of these procedures may require special system design consideration.
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Using the heat from waste incineration to generate electricity requires the addition of generating equipment, while the manufacture, construction, and operation of this equipment also uses energy. And owing to the problem of superheater tube corrosion caused by the hydrogen chloride and other substances formed in conjunction with waste combustion, municipal solid waste (MSW) power generation cannot raise steam temperature very much, and generating efficiency is said to be low, at between 10 and 15%. However, we have found that, in terms of life cycle energy balance, MSW generation is about the same as currently operating commercial power plants. We also examined life cycle energy balance in relation to repowering, which is meant to increase MSW generating efficiency, and reburning, which is aimed at limiting both NOx and dioxin emissions. We found that these are effective methods for energy recovery, and that the gas turbines combined with waste incinerators for repowering have an optimum size that will improve overall efficiency.
Article
Combustion of biomass and municipal solid wastes is one of the key areas in the global cleaner energy strategy. But there is still a lack of detailed and systematically theoretical study on the packed bed burning of biomass and municipal solid wastes. The advantage of theoretical study lies in its ability to reveal features of the detailed structure of the burning process inside a solid bed, such as reaction zone thickness, combustion staging, rates of individual sub-processes, gas emission and char burning characteristics. These characteristics are hard to measure by conventional experimental techniques. In this paper, mathematical simulations as well as experiments have been carried out for the combustion of wood chips and the incineration of simulated municipal solid wastes in a bench-top stationary bed and the effects of primary air flow rate and moisture level in the fuel have been assessed over wide ranges. It is found that volatile release as well as char burning intensifies with an increase in the primary air flow until a critical point is reached where a further increase in the primary air results in slowing down of the combustion process; a higher primary airflow also reduces the char fraction burned in the final char-burning-only stage, shifts combustion in the bed to a more fuel-lean environment and reduces CO emission at the bed top; an increase in the moisture level in the fuel produces a higher flame front temperature in the bed at low primary air flow rates.
Article
A software system for simulating processes for thermal treatment and/or incineration of various types of wastes has been developed. Developing this software was initiated by the need to support and facilitate designers' and operators' activities. The software product is based on modelling — performing a mass and energy balance. A structure of this system is explained as well as the principles of application. Using the simulation program is demonstrated through a case study (incinerator for thermal treatment of various kinds of both industrial and municipal wastes). Flowsheet generation, input data specification, calculation and results of simulation are shown. Various fields of application (design, simulating existing operation, investigation of parametric sensitivity, supporting tool for decision-making) are mentioned. Using this system is comparable with using various professional packages for the simulation of chemical/petrochemical and other industrial processes.
Article
The amount of different persistent organic pollutants (POPs) in the input of waste incinerators was compared to that in the output. Three cases were considered: a rotary kiln incinerating hazardous waste, a grate furnace incinerating municipal solid waste (MSW) and the same grate furnace co-incinerating plastics of waste of electrical and electronic equipment (WEEE) and automotive shredder residue (ASR) with MSW. The mass balance for PCBs in the rotary kiln indicates that these POPs are destroyed effectively during incineration. The grate furnace can be a sink or source of PCDD/Fs and PCBs depending on the concentrations in the incinerated waste. In order to compare the total amount of POPs in input and output, a methodology was developed whereby the amount of POPs was weighed according to minimal risk doses (MRDs) or cancer potency factors. For both incinerators the PCDD/Fs, PCBs and polyaromatic hydrocarbons (PAHs) are the main contributors to total weighed POP output. In MSW, the PCDD/Fs, PBDD/Fs and polybrominated diphenylethers (PBDEs) are the main contributors to the weighed POP input. The ratios of the weighed POP-input over -output clearly indicate that the rotary kiln incinerating hazardous waste is a weighed POP sink. The grate furnace incinerating MSW is a weighed POP sink or source depending on the POP-concentrations in the waste, but the difference between output and input is rather limited. When e.g. ASR and plastics of WEEE, containing high concentrations of PBDEs and PCBs, are co-incinerated in the grate furnace, it is clearly a weighed POP sink.
Article
Detailed mathematical simulations as well as experiments have been carried out for the combustion of wood chips and the incineration of simulated municipal solid wastes in a bench-top stationary bed and the effects of devolatilisation rate and moisture level in the fuel were assessed in terms of ignition time, burning rate, reaction zone thickness, peak flame temperature, combustion stoichiometry and unburned gas emissions at the bed top. It is found that devolatilisation kinetic rate has a noticeable effects on the ignition time, peak flame temperature, CO and H2 emissions at the bed top and the proportion of char burned in the final stage (char burning only) of the combustion. However, it has only a minor effect on the other parameters. Reaction zone thickness ranges from 20 to 55 mm depending on the moisture level in fuel and an increase in the moisture level causes a shift of the combustion stoichiometry to more fuel-lean conditions.
Article
This paper presents a new development in the study of a rotary kiln incinerator. The modelling of the furnace has been divided into two parts. On the one hand, a model describing the physico-chemical processes which occur within the burning bed of municipal solid waste (assumed to be a mixture of wood, cardboard and PVC) has been set. This model mainly relies on the assumptions of plug flow and macroscopic pyrolysis kinetics of burning waste. On the other hand, C.F.D. has been used to describe the processes occurring within the gaseous phase of the kiln and of the post combustion chamber (turbulence, combustion, radiation). A data processing tool has been built to automate the data exchanges between the two parts of the model. Some results of the overall model are shown in two different situation (working with and without extra burner).
Book
Until recent years knowledge of chemical processing was descriptive and qualitative. In 1810 modern chemical theory was born and process description became quantitative. Then about 1900 the quantitative engineering approach was developed, first for physical changes, called the Unit Operations, and somewhat later for chemical operations. This we call the American approach. In 1957 European chemical engineers brought together the design of chemical and their related physical operations under the name of Chemical Reaction Engineering, or CRE. This approach and name received practically universal acceptance. Today the methods of CRE are widely used in the processing of biochemical and all sorts of other systems, This talk wanders through this development.
Article
The formation of hexavalent chromium Cr(VI) during waste incineration processes is of interested because its carcinogenic characteristic. The objective of this study is to simulate the formation of Cr(VI) species under various operating temperatures and input waste compositions during incineration by a thermodynamic model. The results show that the major hexavalent chromium species are CrO2Cl2(g) and CrO3(g). Chlorine and oxygen can increase the formation of Cr(VI) species; while hydrogen, sulfur, sodium, and calcium can inhibit. The input waste composition has greater effect on the formation of hexavalent chromium species than operating temperature.
Article
Remediation action is critical for the management of polychlorinated biphenyl (PCB) contaminated sites. Dozens of remediation technologies developed internationally could be divided in two general categories incineration and non-incineration. In this paper, life cycle assessment (LCA) was carried out to study the environmental impacts of these two kinds of remediation technologies in selected PCB contaminated sites, where Infrared High Temperature Incineration (IHTI) and Base Catalyzed Decomposition (BCD) were selected as representatives of incineration and non-incineration. A combined midpoint/damage approach was adopted by using SimaPro 7.2 and IMPACTA2002+ to assess the human toxicity, ecotoxicity, climate change impact, and resource consumption from the five subsystems of IHTI and BCD technologies, respectively. It was found that the major environmental impacts through the whole lifecycle arose from energy consumption in both IHTI and BCD processes. For IHTI, primary and secondary combustion subsystem contributes more than 50% of midpoint impacts concerning with carcinogens, respiratory inorganics, respiratory organics, terrestrial ecotoxity, terrestrial acidification/eutrophication and global warming. In BCD process, the rotary kiln reactor subsystem presents the highest contribution to almost all the midpoint impacts including global warming, non-renewable energy, non-carcinogens, terrestrial ecotoxity and respiratory inorganics. In the view of midpoint impacts, the characterization values for global warming from IHTI and BCD were about 432.35 and 38.5 kg CO(2)-eq per ton PCB-containing soils, respectively. LCA results showed that the single score of BCD environmental impact was 1468.97 Pt while IHTI's score is 2785.15 Pt, which indicates BCD potentially has a lower environmental impact than IHTI technology in the PCB contaminated soil remediation process.
Article
Texto sobre los aspectos prácticos de la transferencia de calor que aplican directamente en la industria. Centrado en la combustión atmosférica y los combustibles gaseosos, el autor desarrolla su exposición en tres partes: bases de la transferencia de calor en la combustión; conceptos generales de transferencia de calor en los sistemas industriales de combustión y aplicaciones específicas de la transmisión del calor a la combustión industrial.
Article
A mathematical model was presented in this paper for the combustion of municipal solid waste in a novel two-stage reciprocating grate furnace. Numerical simulations were performed to predict the temperature, the flow and the species distributions in the furnace, with practical operational conditions taken into account. The calculated results agree well with the test data, and the burning behavior of municipal solid waste in the novel two-stage reciprocating incinerator can be demonstrated well. The thickness of waste bed, the initial moisture content, the excessive air coefficient and the secondary air are the major factors that influence the combustion process. If the initial moisture content of waste is high, both the heat value of waste and the temperature inside incinerator are low, and less oxygen is necessary for combustion. The air supply rate and the primary air distribution along the grate should be adjusted according to the initial moisture content of the waste. A reasonable bed thickness and an adequate excessive air coefficient can keep a higher temperature, promote the burnout of combustibles, and consequently reduce the emission of dioxin pollutants. When the total air supply is constant, reducing primary air and introducing secondary air properly can enhance turbulence and mixing, prolong the residence time of flue gas, and promote the complete combustion of combustibles. This study provides an important reference for optimizing the design and operation of municipal solid wastes furnace.
incineration of PCB and other hazardous wastes, paper presented at AFRC international symposium on hazardous, Municipal, and other wastes
  • J Bergstrom
  • T Oberg
Bergstrom, J. and Oberg, T. (1987), incineration of PCB and other hazardous wastes, paper presented at AFRC international symposium on hazardous, Municipal, and other wastes, Palm Springs, California, November 2-4, 1984.
Estimation of energy recovery and reduction of CO 2 emissions in municipal solid waste power generation, resources conservation and recycling
  • S Otoma
  • Y Mori
  • A Terazono
  • T Aso
  • R Sameshma
Otoma, S., Mori, Y., Terazono, A., Aso, T. and Sameshma, R. (1997), Estimation of energy recovery and reduction of CO 2 emissions in municipal solid waste power generation, resources conservation and recycling, 20, 95-117.
Destruction Technologies for
  • M Rahuman
  • F L Triferio
  • Pistone
Rahuman, M. Triferio, F.L. Pistone (2000), Destruction Technologies for
  • H Bani-Hani
H. Bani-Hani et al. / Journal of Environmental Chemical Engineering 4 (2016) 624–632
K)=a+bT+ cT 2 +dT 3 and the heat capacities at constant volume Cv are calculated using the following formula: Cv = Cp-R, where R= 8.314 J/mole.K is the air gas constant
  • Cp
Cp (J/mole.K)=a+bT+ cT 2 +dT 3 and the heat capacities at constant volume Cv are calculated using the following formula: Cv = Cp-R, where R= 8.314 J/mole.K is the air gas constant. T is temperature in Kelvin.