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Characterisation of municipal solid waste at landfill, India


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Characterisation of municipal solid waste (MSW) is important for adequate decision making in the management strategy of urban MSW of a city. The objective of this study was to characterise the MSW at a landfill of Pune city, India and suggest appropriate MSW management methods. The investigations showed that biological treatment of MSW will be feasible as it contains high organic matter and moisture content. This would help to divert 70% of the total waste, if solid waste treatment facilities were provided at source, which would lead to enormous cost savings of waste collection, transport and disposal. Energy generation through incineration of MSW was not feasible. The changing pattern of characterisation of MSW in relation to socio-economic changes has been discussed. Though the study was focused on Pune city, investigations will help solid waste management planners, materials recovery facility designers and for estimation of landfill gas emission in developing metropolitan cities.
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Waste and Resource Management
Volume 164 Issue WR4
Characterisation of municipal solid
waste at landfill, India
Mali, Khare and Biradar
Proceedings of the Institution of Civil Engineers
Waste and Resource Management 164
November 2011 Issue WR4
Pages 247–255
Paper 1000038
Received 04/11/2010 Accepted 07/04/2011
Keywords: landfill/recycling & reuse of materials/waste
management & disposal
ICE Publishing: All rights reserved
Characterisation of municipal
solid waste at landfill, India
1Sandip Tanaji Mali ME
Assistant Professor, Sinhgad College of Engineering, Pune,
Maharashtra, India
2Kanchan C. Khare PhD
Professor, Sinhgad College of Engineering, Pune, Maharashtra, India
3Ashok H. Biradar ME, PhD
Professor of Civil Engineering, Bharatratna Indira Gandhi College of
Engineering, Pune, Maharashtra, India
Characterisation of municipal solid waste (MSW) is important for adequate decision making in the management strat-
egy of urban MSW of a city. The objective of this study was to characterise the MSW at a landfill of Pune city, India
and suggest appropriate MSW management methods. The investigations showed that biological treatment of MSW
will be feasible as it contains high organic matter and moisture content. This would help to divert 70% of the total
waste, if solid waste treatment facilities were provided at source, which would lead to enormous cost savings of
waste collection, transport and disposal. Energy generation through incineration of MSW was not feasible. The
changing pattern of characterisation of MSW in relation to socio-economic changes has been discussed. Though the
study was focused on Pune city, investigations will help solid waste management planners, materials recovery facility
designers and for estimation of landfill gas emission in developing metropolitan cities.
1. Introduction
Waste management is an important element of environment
protection. Proper characterisation of municipal solid waste
(MSW) is the fundamental basis for planning of municipal
waste management services (del C Espinosa Llorens et al.,
2008; Oyeola and Babatunde, 2008; Yinghui Zeng et al.,
2005). The knowledge of solid waste sources and types of
waste in a given service area is required in order to design and
operate appropriate solid waste management systems (Tchoba-
noglous et al., 1993). This information is necessary in order to
identify the waste components to target for source reduction
and recycling, and design of material recovery facilities and
waste-to-energy projects (del C Espinosa Llorens et al., 2008).
Waste composition indicates the components of the waste
stream in percentage of the mass or volume. The composition
and characteristics of MSW change with time all over the
world. Even in the same country, waste composition depends
on a number of factors such as social customs, standard of
living, geographical location, climate, season and so on. MSW
is heterogeneous in nature and consists of a number of different
materials which are derived from various types of activities
(CPHEEO, 2000; Oyeola and Babatunde, 2008). National
policy decisions that influence the components of MSW systems
are not possible until data of composition and quantity of solid
waste are available. More than 90% of MSW generated in India
is directly disposed on land in an unsatisfactory manner (Das
et al., 1998). The diverse nature of data about the composition
of MSW necessitates a rigorous study in any given locale. The
objectives of this study were: (a) characterisation of MSW deliv-
ered to Pune city’s landfill, (b) studying the changing trends of
waste characterisation in the past 10 years and (c) to suggest
the appropriate MSW treatment plan.
1.1 Study area
The city of Pune, located at 188310N latitude and 738510E
longitude, is situated in the western region of the Deccan
Plateau at the confluence of the Mula and Mutha rivers in the
state of Maharashtra in India (Figure 1). Pune is one of the
fastest developing urban areas in Asia and ranks eighth at
national level. The present growth is attributable to various
factors such as industrialisation, expanding educational
institutes and information technology (IT) companies and
establishments of various government organisations. One of
the negative impacts of the city’s rapid development is the
increase in MSW generation, resulting in environmental
degradation. Many factors, such as spiralling urban population,
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economic development, consumption patterns, climate and
institutional framework, contribute to MSW generation and the
composition of the waste. Among them, urban population
growth and economic development are vital because they not
only accelerate consumption but also increase the generation of
waste in developing countries (Yousuf and Rathman, 2007).
Pune, with a population approaching 3 400 000, is estimated to
generate about 1200 metric tonnes of MSW daily. The per
capita generation of MSW varies from 0.30 to 0.40 kg per day
per person depending on the economic status of the community
involved. MSW in Pune city has been predicted to increase from
1100 t per day in 2007 to 1800 t per day in 2011 and 2600 t per
day in 2025. The annual rate of increase in solid waste generation
has been forecasted to be 1.29% through 2025 (PMC, 2008).
1.2 Landfill site
The earlier landfill site of Pune city was at Kothrud, which
closed in 1982. The present landfill site is at Urali Devachi on
Pune–Saswad road, which is about 15 to 18 km from Pune and
lies at 18828016.1300 Nand73856057.6200 E (Figure 2). It covers
an area of 64 ha (6.40 10
) of which 15 ha were permanently
sealed off as it was already landfilled (Khare and Mali, 2007). The
original site was a partial stone quarry and had deep excavated
areas. Landfill had been operational since 1983 and it mainly con-
tains residential waste, market waste, institutional waste and
waste from slaughterhouses and information technology (IT)
industries. The waste is transported to the landfill site from four
transfer stations. At present the total amount of landfill waste is
about 0.438 million t per annum. Although the segregation of
waste was undertaken at source, such as household level, hotels
and restaurants for dry and wet waste, waste received at the land-
fill site was mostly of a mixed nature. A significant amount of
recyclable materials was being recycled by the informal sector
through scavengers on the landfill siteand supplied to appropriate
processing factories as raw material.
Since there was a lack of awareness in the past about solid
waste disposal, people used to dump unsegregated waste and
Waste and Resource Management
Volume 164 Issue WR4
Characterisation of municipal solid waste
at landfill, India
Mali, Khare and Biradar
Figure 1. Location map of Pune. Source:
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also Pune Municipal Corporation (PMC) used to dispose the
unsegregated waste on the dumping site without any soil
cover or leachate management. This gave rise to problems
such as landfill fires, smoke, bad odour, leachate and so on.
The height of waste dumped was 18 m. Recently PMC has
agreed to allot 20 000 m
of land for an integrated solid waste
management plant. The present practice of solid waste
disposal consists of biological decomposition of waste and
landfilling. An effective microorganism solution has been
applied over solid waste to decompose the organic matter
(PMC, 2010). Complete decomposition is not possible because
of the unsegregated waste. It was understood from the official
sources that only small quantities (150 t/day) of decomposed
organic matter were segregated. These were then collected by
local farmers and used as manure while the remaining solid
waste was left and used for landfilling. The average annual
emission of suspended particulate matter (SPM), sulfur
dioxide (SO
) and nitrogen oxide (NO
) at the disposal site
was 1708.3mgm
, 285.33 mgm
and 234.07 mgm
tively. The SPM, sulfur dioxide and nitrogen oxide concentra-
tions are more than those stipulated by Indian MSW standard
limit (CPHEEO, 2000; Dhere Amar et al., 2008). The burning
of solid waste creates heavy smoke and dust pollution and
dousing the waste with water to prevent fires, which also
results in production of leachate (Purandare, 2003). The
landfill does not have leachate and gas collection systems.
The leachate produced from the landfill has changed the
characteristics of the ground aquifer within the vicinity of the
landfill site (Nissar Shazia et al., 2008). The solid waste
disposal and management practice of PMC have caused a lot
of environmental problems such as groundwater contamina-
tion, frequent landfill fires, and a bad odour problem in Urali
Devachi village, all of which require immediate attention
(Khare and Mali, 2007).
2. Materials and methods
2.1 Sample collection and segregation
Sampling for the present work was done monthly from January
2008 to November 2008 to account for seasonal variations and
representative characteristics of MSW. The sampling locations
were identified in consultation with municipal authorities
responsible for the operation of the site to obtain a representa-
tive sample (Figure 2). A total of 25 samples were characterised
for physical and chemical analysis of MSW. The samples were
collected from three to four locations as unloading of waste
was done at different places. Special care was taken at time of
sampling to obtain a representative sample. A typical load of
the solid waste in a vehicle weighs between 4500 and 9000 kg.
It was not practically possible to separate the entire load or a
load from an even larger vehicle (Yinghui Zeng et al., 2005).
The solid waste unloaded from the vehicle created a small
heap of waste. It was spread horizontally by an earth mover
and approximately four quarters were made, one of which
was selected for sampling (European Recovery & Recycling
Association, 1993; Peavy et al., 1985; Tchobanoglous et al.,
1993). The volume of each sample was about 100 kg for physical
analysis of MSW. Using clean polyethylene airtight bags, 5 kg
of mixed sample were collected and labelled for each location
and subjected to chemical analysis. Initially it was analysed
only for moisture content and later on for other parameters
by proper storing.
2.2 Sorting and processing of samples
Waste samples were manually sorted with the help of landfill
workers into seven categories, namely plastic, paper, cloth
(rubber, leather and synthetics), metals, stone, glass and
organic matter (Table 1). Sorting was based on visual
inspections, and small particles, which would not be visually
identified, were classified as stone. Each category of waste was
weighed separately by an electronic weighing balance (Seco
Electronic weighing balance). Standard personal safety
procedures were followed during the sorting process such as
wearing gloves, goggles, apron and shoes. For analytical
purposes the samples were cut and shredded, except for bulky
materials (e.g. metals, glass and stones). The size of particle
for the processed fraction was less than 4 mm for volatile
solids, ash, organic matter and pH, thus excluding the bulky
material for the analysis. This meant that compared with the
actual landfill conditions some of the variables in the samples
had higher observed concentrations relative to their in situ
2.3 Laboratory sample analysis
(a) pH. The dried MSW waste was analysed for pH. The pH
was analysed by shaking 50 g of waste material in 250 ml
of distilled water for 24 h and analysing by pH meter
(Elico India, LI,127) (USEPA, 2001).
Waste and Resource Management
Volume 164 Issue WR4
Characterisation of municipal solid waste
at landfill, India
Mali, Khare and Biradar
Figure 2. Sampling stations of MSW at Urali Devachi landfill
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(b) Organic matter. Some 25 g of dry waste were ignited at
3608C for 24 h to evaluate the organic matter (USEPA,
(c) Moisture content. Moisture content was determined
gravimetrically. Samples in airtight bags were used to
determine the moisture content. Mixed samples of 100 g
were taken and dried in the oven at 1058C for 24 h,
cooled in a desiccator and the difference in weight
recorded (Vesilind et al., 2003). Moisture content is
per cent sample weight lost on drying.
(d) Total solids, volatile solids, fixed solids. Some 50 g of wet
sample were dried at 103–1058C for the total solids. Then
total solids were ignited in a muffle furnace at 550 508C
for 1 h. The fraction during ignition was termed ‘volatile
solids’ and the fraction of solids remaining after ignition
was called ‘fixed solids’ (USEPA, 2001).
(e) Density by core cutter method. A core cutter consisting of
hollow steel cylinder with 10 cm internal diameter and
about 13 cm high and a 2.5 cm high dolly is driven in the
landfill with the help of a suitable rammer. The cutter
containing the MSW was dug out of the landfill, the dolly
was removed and excess MSW was trimmed off. Density
was determined by the mass of MSW in the cutter divided
by the volume of core cutter and expressed in terms of
kg mm
(Punmia et al., 1996).
(f) Organic carbon (C). The solid waste was pulverised after
air drying it to pass a 0.42 mm sieve. The method was
used to determine the organic carbon (C) content of the
waste sample which is similar to the procedure used to
measure soil organic C content (Naresh Kumar and
Sudha Geol, 2009).
(g) Total Kjeldhal nitrogen (N). TKN was analysed
according to the application note supplied by Teactor
(Perstorp Analytical/Tecator AB, 1995).
3. Results and discussions
3.1 Characterisation of solid waste
Waste samples collected from Urali Devachi landfill site from
different locations (Figure 2) and for different months were
characterised for physical and chemical parameters. All physical
components of the bulk waste were segregated manually on site
and the results are summarised in Table 2. The total weight of
each wet waste category was determined and expressed in per-
centage. Proximate analysis of all collected samples was done
in the laboratory and the results are given in Table 3. Mean
values and standard deviations were calculated for different
components of MSW. From a practical point of view, the
empirical data obtained in the present study appear to be case
dependent and can be used only to assist for planning of solid
waste management of Pune landfill site. The physical survey
of the landfill site shows that the organic fraction includes
paper, cardboard, rubber/leather/synthetics and compostable
matter. The inorganic fraction includes plastic, metals, earth
ware, stone, brickbats, ceramics, glass and so on. Tables 2
and 3 show the physical and chemical composition of the
waste respectively based on weighing of wet samples. The
degradable materials form a major fraction and metal was the
smallest composition of MSW for various months. Organic
matter varied from 46.0% to 85.4%. The coefficient of variation
for compostable matter was 13.80%, which was less than the
maximum variation coefficient observed; that is, 22% (da
Grac¸ a Maderia Martinho et al., 2008). The moisture content
at the present landfill site varied from 38.91% to 58.91%.
This indicates that waste contains sufficient moisture content
to initiate the biodegradation. The increase in recyclables
(plastic, paper, metal, etc.) has given rise to the phenomenon
of scavenging activity (about 300 to 400 scavengers) where the
recycling units have mushroomed near the landfill site, provid-
ing employment to unskilled labour. The average composition
of MSW includes plastic 7.1% (4.1), paper 6.9% (4.5),
cloth 7.8% (5.4), metal 0.7% (0.6), glass 1.2% (1.4),
organic matter 69.3% (9.6) and stone 7% (5.2) (Figure 3)
while density was found to be 854.96 (212.86) kg m
Figure 4 shows the monthly variation of MSW composition.
The presence of carbon compounds in MSW varied from
4.05% to 19.28% with average 11.62%, which was essential
for landfill gas formation. Nitrogen and phosphorus are also
essential for the microbial activity in a landfill. The average
nitrogen content was 0.64% on a wet weight basis. The
average carbon to nitrogen (C/N) ratio was 20.09 4.38. The
Waste and Resource Management
Volume 164 Issue WR4
Characterisation of municipal solid waste
at landfill, India
Mali, Khare and Biradar
Waste composition
Waste components
1 Plastic Plastic bags, packaging
material, plastic bottles
2 Paper Packaging paper, cardboard,
wrapper, newsprint,
magazines, office paper
3 Cloth Rubber, clothes, synthetic,
cables, leather
4 Metal Ferrous, non-ferrous, tin
cans, metal foils
5 Stone Stone, construction material,
brickbats, sand, aggregate,
ceramics, crockery
6 Glass Clear, brown, green, other
7 Compostable Food, vegetable, yard
trimmings, wood, leaves,
Table 1. Waste composition category
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average values of various chemical parameters were moisture
content 48.08% (5.29), pH 7.85 (0.37), organic matter
32.83% (8.85), total solids 70.28% (6.32), volatile solids
62.61% (7.92) and fixed solids 37.38% (7.92), carbon
11.62% (4.77), nitrogen 0.59% (0.24) and C/N ratio 20.09
3.2 Variation of MSW characteristics with time
There has been a remarkable effect on the waste generation of
the city from 2001 to 2008 (see Figures 3 and 5) which can be
very well related to the overall economic development that
has taken place. Organic matter had increased from 51.5% in
2001 to 69.3% in 2008 (Table 4). The municipal corporation
had taken up the issue of awareness programmes since 1999.
The corporation has offered a 5% rebate on property tax to
those citizens who will provide appropriate MSW management
facilities (PMC, 2008) There was an increase in the number of
city scavengers, collecting the recyclable materials, and the
only waste left was organic matter and non-recyclable materials.
The biodegradable fraction was quite high, essentially attributa-
ble to the habit of using fresh vegetables in India (CPHEEO,
2000). The number of restaurants and hotels has increased,
which was also contributing to the increase in organic matter.
The high biodegradable fraction warrants frequent collection
and removal of solid waste from the collection points.
It has been observed that the percentage of recyclable material
(paper, plastic, glass and metal) delivered to the landfill decreased
from 20% in 1990 to 6.2% in 2001. There was an increase of
recyclable material by 9.57% from 2001 to 2008, owing to
Waste and Resource Management
Volume 164 Issue WR4
Characterisation of municipal solid waste
at landfill, India
Mali, Khare and Biradar
Glass Organic
1 26/1/2008 1 5.29
.4 100.0
.1 100.0
.4 100.0
4 16/2/2008 1 9.09
.4 100.0
.8 100.0
6 30/3/2008 1 7.54
.9 100.0
.2 100.0
.5 100.0
9 13/4/2008 1 7.59
.4 100.0
10 2 5.74
.9 100.0
11 3 9.85
.5 100.0
12 29/5/2008 1 5.86
.2 100.0
13 2 11.011
.0 100.0
14 3 7.67
.3 100.0
15 19/7/2008 1 2.44
.9 100.0
16 2 5.34
.1 100.0
17 19/8/2008 1 6.724
.0 100.0
18 2 17.34
.2 100.0
19 3 19.34
.0 100.0
20 28/9/2008 1 4.82
.9 100.0
21 2 9.01
.4 100.0
22 19/10/2008 1 2.74
.8 100.0
23 2 2.87
.8 100.0
24 9/11/2008 1 3.43
.8 100.0
25 2 5.85
.8 100.0
Mean 7.16
.3 100.0
std dev. 4.14
.4 9.6
aplastic bags, packaging material, plastic bottles; b paper, packaging
paper, cardboard, wrapper; c rubber, clothes, synthetic, cables;
ddifferent metals, tin cans, metal foils.; e stone, construction
material, brickbats, sand, aggregate, ceramics, crockery; f food,
vegetable, yard trimmings, wood, leaves, grass
Table 2. Physical analysis of MSW of Urali Devachi landfill
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Waste and Resource Management
Volume 164 Issue WR4
Characterisation of municipal solid waste
at landfill, India
Mali, Khare and Biradar
pH Density:
kg m
content: %
C: % N: % C/N
1 26/1/2008 1 7.9 786 58.91 44.54 83.34 51.94 48.06 12.80
.3 725 43.67 35.17 73.13 57.51 42.49 9.40
.53 17.74
.8 730 50.14 18.51 66.08 74.47 25.53 17.14 0.88 19.48
4 16/2/2008 1 8.2 690 51.08 24.06 72.99 69.45 30.55 11.44 0.49 23.35
.4 781 48.75 30.91 72.87 64.72 35.28 11.40
.55 20.73
6 30/3/2008 1 7.6 948 49.63 44.75 74.90 51.94 48.06 12.77 0.63 20.27
.8 945 43.37 37.25 69.72 57.31 42.69 15.36 0.89 17.26
.9 1137 54.54 27.53 73.30 66.76 33.23 14.72 0.71 20.73
9 13/4/2008 1 8.3 1415 42.66 28.06 62.48 67.37 32.62 16.99 0.81 20.98
10 2 7.8 1312 46.46 22.24 69.93 74.26 25.73 13.02 0.67 19.43
11 3 7.9 1050 45.63 41.68 69.14 56.52 43.48 15.74 0.71 22.17
12 29/5/2008 1 8.1 530 43.92 37.08 67.37 59.38 40.61 14.53 0.92 15.79
13 2 8.5 560 47.76 34.94 66.07 61.11 38.89 4.55 0.22 20.68
14 3 8.1 650 45.828
.37 69.32 68.37 31.63 9.68 0.56 17.29
15 19/7/2008 1 7.9 760 56.78 25.377
.15 71.69 28.31 6.99 0.42 16.64
16 2 8.3 990 52.848
.35 74.93 50.649
.05 0.23 17.61
17 19/8/2008 1 7.7 950 38.91 36.59 60.10 60.57 39.43 18.91 0.97 19.49
18 2 7.9 950 39.96 24.19 57.40 71.33 28.64 19.28 0.93 20.73
19 3 8.9 830 39.730
.96 59.65 65.634
.419 0
.92 20.65
20 28/9/2008 1 8.6 795 53.91 42.675
.21 52.03 47.97 9.36 0.53 17.66
21 2 8.2 830 52.83 48.86 80.37 48.03 51.97 8.06 0.39 20.67
22 19/10/2008 1 7.4 885 51.43 34.92 76.12 61.28 38.72 7.06 0.41 17.22
23 2 8.1 780 50.34 25.97 70.22 64.64 35.36 6.47 0.34 19.03
24 9/11/2008 1 8.2 635 47.16 29.55 66.45 64.69 35.31 4.93 0.316
25 2 7.7 710 46.06 18.52 68.80 73.79 26.21 7 0.18 38.89
std dev.
Table 3. Chemical analysis of MSW of Urali Devachi landfill (wet basis)
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changing lifestyle, increase in economic status, material
consumption pattern,educational institutes, IT sector, throw-
away culture and so on. This increase has given rise to the
practice of scavenging, especially in the city and landfill area,
providing employment to hundreds of unskilled workers
(Shuchi Gupta et al., 1998, Suman Mor et al., 2006). Inert
matter has increased from 15% in 1999 to 40.60% in 2001 (an
increase of 25%) as shown in Figure 5. This was attributed to
the practice of inclusion of the street sweepings, drain silt and
construction and demolition waste in MSW. High inert content
increases the densities of MSW. Inert matter has decreased
from 40% in 2001 to 7% in 2008 (a decrease of 33%) owing to
improvements in the road surface and increase in concrete road
length and construction and demolition waste not being allowed
in MSW. The reduction in inert matter caused an increase in the
percentage of organic and recyclable matter. There was small
variation in organic matter, paper and plastic between 2007 and
2008. The percentage of glass and metal has decreased from 6%
to 1.2% and 4% to 0.7% respectively, from 2007 to 2008.
Waste and Resource Management
Volume 164 Issue WR4
Characterisation of municipal solid waste
at landfill, India
Mali, Khare and Biradar
Paper 6·9%
Cloth 7·8%
Plastic 7·1%
Glass 1·2%
Metal 0·7%
Organic 69·3%
Stone 7%
Figure 3. Physical composition of MSW of Pune (year 2008)
Parameter a b c d
Physical parameters
1 Organic matter: % 55 51.570 69
2 Paper: % 5 1.98 6
3 Rubber, leather,
synthetics: %
4 Plastics: % 5 2.37 7
5 Clothes: % NA 1.2NA 7
6 Glass: % 10 1.16 1
7 Metal: % NA 0.94 0
8 Inert matter: % 15 40.65 7
9 Density: kg m
NA 437.00 NA 854.96
10 Gross calorific value:
kcal kg
NA 937.00 NA NA
Source: a – CPCB (1999); b – Extracted from HUDCO DPR, 2001;
c – Environmental Status Report of Pune Municipal Corporation
2006–07; d – Results of the study for year 2008; NA not available.
Table 4. Composition of municipal solid waste of Pune
Jan. Feb. March April May July Aug. Sept. Oct. Nov.
Month (
ear 2008)
Figure 4. Variation of physical composition of MSW
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3.3 Necessity of waste management
The results show that organic matter and moisture content in
Urali Devachi landfill waste was significantly higher, which
causes various environmental and social problems within the
vicinity of the landfill. There are frequent landfill fires through-
out the year, mostly in summer. Groundwater resources have
been contaminated due to landfill leachate. The socio-economic
development of villages/towns adjacent to landfill is affected. It
is mandatory for all cities in India to have the solid waste
management system as per MSW 2000 rules and regulations
(CPHEEO, 2000), which specifies that only inorganic waste
should be scientifically disposed. Therefore there is a need to
take appropriate action to manage landfill waste.
3.4 Appropriate method of MSW management
Management of the MSW of a city depends on population
density, peripheral development, socio-economic conditions,
residents’ solid waste management habitual culture and so on.
Characterisation of MSW of Pune landfill showed that
biodegradable matter was 70% and the remaining 30% was
recyclable and inert matter. Organic waste generation was
about 831 t/day, recyclable 190 t/day and inert was about
179 t/day.
The total area of Pune city was divided into three zones, zone
one being central Pune, zone two the new developments and
zone three included suburbs and areas of these zones, which
were 42.64 km
, 103.28 km
and 98.04 km
respectively (PMC,
2010). PMC had made it mandatory for new constructions in
zone two and zone three to have organic and recyclable waste
management facilities on their premises. Organic matter of
waste can be treated by composting (aerobic or anaerobic
composting and vermicomposting) or by anaerobic digestion
process. Composting of waste yields soil conditioner, which
can be used for gardening purposes, and anaerobic digestion
will yield gas which can be used as fuel or electricity generation,
which will be useful for various purposes in housing complexes.
The core area of the city (zone one), the slum area, vegetable
markets, slaughterhouse, gardens and parks and so on do not
have enough space to treat the solid waste. Instead of transport-
ing the waste from those areas of city to the present landfill
location, it is proposed to use the partial space from existing
reserved space for parks, gardens, playgrounds and recreation
for treating the compostable waste. The total reserved area is
127.68 ha at 106 places within the city (PMC, 2010). The end
products of biological waste treatment (compost or gas) will
satisfy some manure or electricity requirements of the reserved
Solid waste treatment at source can help to divert 70% of the
total waste and will lead to enormous savings in the cost of
waste collection, transport and disposal. The recycling matter
should go to the recycling industry. This will reduce the
Waste and Resource Management
Volume 164 Issue WR4
Characterisation of municipal solid waste
at landfill, India
Mali, Khare and Biradar
Organic matter Paper Plastic Glass Metal Inert matter
onents of MSW
Figure 5. Variation of MSW composition with time
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burden on landfill and environmental effects as landfill will also
be minimised (Suman Mor et al., 2006).
Incineration for energy generation from MSW was not feasible
as organic content was low and moisture content was high. The
inorganic portion of waste sand, silt, clay, fine earth and ash
can be disposed at engineered landfill as per MSW rules and
regulations (CPHEEO, 2000). The landfill site should be
fenced to restrict unauthorised entry. The sanitary landfill site
should have proper access roads for the container carriers.
Landfill should be surrounded by open drains to collect surface
runoff during monsoon. After the life of the sanitary landfill site
is over the site should be used for gardening purposes only, after
laying a top soil layer of 0.5 m depth.
4. Conclusion
(a) The first step in waste management is to gain an
understanding of the waste types being generated in
order to design appropriate collection and disposal
(b) Characterisation of MSW of the landfill site of Pune city
shows that it contains a high percentage of organic matter
(69.3%) and organic content in MSW to the tune of
32.83%, and average moisture content 48.08%, which
confirms the viability of biological treatment.
(c) Effective management of solid waste at the landfill site of
Pune city will reduce the environmental effects of landfill.
(d) The investigations of the present study will be useful for
Pune city as well as for developing metropolitan cities
when making decisions regarding the integrated solid
waste management strategy and for selection of treatment
and disposal options.
The authors wish to acknowledge the financial support pro-
vided by the Board of College and University Development,
University of Pune, Maharashtra and the support provided by
authorities of Pune Municipal Corporation and staff at Ural
Devachi landfill site.
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Waste and Resource Management
Volume 164 Issue WR4
Characterisation of municipal solid waste
at landfill, India
Mali, Khare and Biradar
... It was not practically possible to separate the entire load or a load from an even larger vehicle (Zeng et al., 2005). A coning and quartering method was used for MSW sampling (Mali et al., 2011;Peavy et al., 1985;Tchobanoglous et al., 1993). MSW was spread horizontally and approximately four quarters were made and out of that one quarter was selected for sampling. ...
... Recyclables are assumed to be separated and sent to the recycling facility. Composting and anaerobic digestion treatment options were suitable for waste containing highly compostable matter (Mali et al., 2011). By focusing on capital cost and land requirement, the pyrolysis-gasification and mass incineration require less cost rather than other treatment options (Saini et al., 2012). ...
Full-text available
The aim of the study was to assess municipal solid waste (MSW) management system through life-cycle assessment methodology. A field study was carried out for characterisation of MSW and leachate analysis for the landfill site of Kolhapur city, India. The total MSW generation rate in the city was 180 t/d, out of which the organic matter content was 70·33% and the inorganic matter content was 29·67%. The characteristics of the leachate showed more pollution strength compared with the standards. SimaPro software was used for analysing environmental burden through different impact categories. Municipal waste management scenarios such as open dumping, composting, anaerobic digestion and pyrolysis–gasification were compared with the centre for environmental studies method. The impact assessment categories that were considered were emission of greenhouse gases, ozone layer depletion, acidification, eutrophication, ecotoxicity, human toxicity and summer smog. The result of this study has revealed a more feasible treatment scenario based on environmental impact analysis. Open dumping has shown the highest environmental impact. Pyrolysis–gasification with energy recovery potential and composting is an environmentally favourable MSW management option.
... However, the difference between developed and developing countries comes into the picture when a closer look is taken at how the process is managed, particularly in terms of safety. With the relatively strict enforcement of environmental and public health regulations, safety is usually assured when wastewater recycling is practiced in developed countries (Mali et al., 2011). Unfortunately, the same is not true about most developing countries where the use of untreated or partially treated wastewater in agriculture is still prominent. ...
This study was aimed at identifying how drip irrigation could be useful in controlling heavy-metal issues, practically and affordably. A vegetable crop (i.e. cauliflower) was the subject of the test. Heavy-metal accumulation in soils and uptake by cauliflower curds were observed for two consecutive years. Municipal wastewater and groundwater were used for irrigation, to make it a comparative study. There were eight treatments: drip irrigation with groundwater through inline (non-pressure-compensating) surface drip (T1), inline subsurface drip (T2), bioline (pressure-compensating) subsurface drip (T3), bioline surface drip (T4) and the same drip systems using primarily treated municipal wastewater (T5 to T8). The results showed that significantly higher concentrations of heavy metals – namely, copper, iron, manganese and zinc – were recorded in cauliflower curds irrigated with wastewater compared with those irrigated with groundwater. Subsurface placement of pressure-compensating drip laterals was found more effective in reducing the heavy-metal concentrations in both cauliflower and soil profile compared with surface-placed non-pressure-compensating drip laterals. This study suggests that drip irrigation systems could be an effective method to reduce heavy-metal concentration in vegetable crops and soils irrigated with treated municipal wastewater.
... Studies investigating the fractions of recyclable and compostable materials in the municipal waste reaching the final disposal site found that in 1999-2000 an unusually large fraction of the municipal waste consisted of inerts such as soil and ash (40.3%) and the rest comprised of compostable matter (41.8 %), paper (5.7%) and textiles (3.5%) which once soiled are difficult to recover (Narayanan, 2009;Sharholy et al., 2008;Tanaji et al., 2011). The fractions of recyclable materials that can be cleaned after recovery such as plastic (3.9%), glass (2.1%) and metal (1.9%) were surprisingly low (Sharholy et al., 2008). ...
... Waste sampling was performed according to coining and quartering method (Tchobanoglous et al., 1993). Bioreactors were loaded with manually shredded MSW having size 30-70 mm and were adjusted to average MSW composition determined at Urali Devachi, Pune City (Mali et al., 2011). The solid waste composition in first group based on weight as organic 69%, paper 7%, cloth 8%, plastic 7%, metal 1%, stone 7% and glass 1% and in second group was organic 91% and paper 9%. ...
Solid waste management has received attention due to the rise in per capita waste generation worldwide. The widespread impact on the environment is notably high due to improper waste management. Currently, solid wastes are managed by different techniques over which, plasma pyrolysis seems advantageous due to its environment-safe processing, production of high-quality syngas/hydrogen, and a significant reduction in solid residue. Plasma pyrolysis technology converts solid wastes to energy by thermo-chemical processing in absence of oxygen. It offers a sustainable waste management option with minimal amount of harmful emissions. This review focuses merely on the current status of plasma pyrolysis technology. It critically reviews the research carried out on plasma pyrolysis technology for the treatment of a wide range of solid wastes, including hazardous waste. The compositions and applications of solid residue and syngas generated from plasma pyrolysis process are also incorporated. The plasma reactor designs and plasma generation sources are also investigated. A study of cost estimation to process different wastes is also presented. Furthermore, the challenges of this technology and recommended actions are also identified to make this technology a viable option on a larger scale. Plasma pyrolysis is a state-of-the-art technology that offers a promising future for effective treatment of solid waste.
Quantification, measurement of quality, post-treatment, and leachate control has been a significant problem due to the dumping of waste in an unscientific manner across the globe, and especially in developing countries like India. In this context, the objective of this study was to investigate the degradation of fresh mixed municipal solid waste (MSW) in an anaerobic landfill reactor operated with rainfall addition in laboratory conditions. Experiments were carried out in a landfill reactor of 1 m length × 1 m width × 1.1 m height. The reactor was simulated with 50 years weighted average actual rainfall rate of India. It contained the waste composition of 73% wet waste (food and kitchen) and 27% dry waste (paper, plastic, wood, textiles, and others). The leachate parameters were continually monitored for 39 weeks. In the fresh MSW landfill reactor it was evident that concentrations of leachate parameters were high initially, and there was a significant decrease in BOD5 (7041-39310 mg L-1), COD (15692-71630 mg L-1) and TS (9077-33200 mg L-1) in leachate. Therefore, rainfall had a direct influence on leachate quality. The developed first-order decay models were used for BOD5, COD, and total solids with adjusted R2 of 0.83, 0.92, and 0.96, respectively. Therefore, this model can be applied for leachate strength estimation at any given time from the period of deposition of waste under similar rainfall and waste compositions, and is largely applicable in India and tropical areas. This study is expected to be a good simulation for cities with the waste composition of high wet waste (>70%) as the estimations of important design parameters such as BOD5, COD, VFA, and NH4+-N were studied in this research. As the importance of moisture (precipitation) has been established in this study, some moisture additions can be designed in areas with low rainfall, such as arid zones.
This study was conducted as part of the Integrated Waste Management Plan of Gachsaran county. Gachsaran county suffers from serious problems with regard to municipal solid waste management (MSWM). Poor collection and transportation systems, poor final disposal in landfill, illegal recycling activities and illegal waste pickers are among current problems. The required data regarding waste characteristics were collected through field studies. The current MSWM in Gachsaran county including waste generation, handling, separation and transportation as well as physical and chemical analyses were examined. According to the results, urban and rural per capita waste generation rates in the county are 844·5 and 551·1 g/d, respectively. Biodegradable materials have the highest percentage of the municipal waste composition. Also, since the current landfill location was seriously opposed by locals, a landfill site-selection study was performed by using Arc GIS software. Considering certain criteria, the analytical hierarchy process was used to determine the relative weight of each criterion. Finally, a number of suggestions were provided to enhance the performance of waste management in the study area.
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Waste management is an important element of environmental protection. Proper characterization of municipal solid waste is fundamental for the planning of municipal waste management services. The objectives of this study were to estimate the percentage of various components of household and market waste generated from source and also the seasonal composition of household waste. The domestic and market solid wastes generated during a period of 48 days by a sampling of 200 households and 40 market waste samples of different socioeconomic characteristics were classified and weighed at source between March 2004 and April 2006. The household solid waste mainly consisted of putrescible waste (68.16%), paper (12.46%), nylon (7.68%), Plastic (3.64%), glass (1.78%), metal (2.08%), and garden waste/grit (4.20%). The market waste consisted of putrescible waste (68.98%); paper (23.57%), nylon (3.92%), Plastic (1.77%) and metal (1.77%). The seasonal composition shows a high generation of putrescible during the wet season and nylon during the dry season.
Full-text available
The urban centres of India produce 120,000 t of solid waste per day. The unscientific disposal of solid waste creates many environmental and pollution problems. The 1000-1200 t of solid waste in Pune municipal area is disposed at Urali-Devachi village. This communication reveals the problems of air and groundwater pollution caused due to unscientific disposal of solid waste observed at Urali-Devachi village. The average annual emission of SPM found at the disposal site is 1708.3 μg/m 3. The average annual emission of SO 2 in landfill site is 285.33 μg/m 3 and NO x is 234.07 μg/m 3. The SPM, SO 2 and NO x concentrations are more than those stipulated by the Indian standard limit. The leachate samples are acidic and corrosive in nature. The COD and BOD of tested well-water samples III and IV are 834, 703 mg/l and 716, 412.16 mg/l respectively. The concentration of sodium in well-water samples III and IV is 2437 and 2612 mg/l respectively. The COD, BOD and sodium concentration in well water are higher than the limits of IS: 2291. Rag-pickers, workers, vehicle drivers, and those residing in the nearby areas are continuously exposed to air pollution. It has been found that leachates originate from solid waste landfill-contaminated groundwater. Well water found in Urali-Devachi village is not safe for drinking, outdoor bathing, propagation of aquatic life, industrial cooling and for irrigation. If this municipal solid waste landfill continues, it may create a toxic bomb in future. Conversion technology entailing conversion of solid waste to energy is proving helpful for decomposing solid waste without affecting the environment. Also, the community-based solid waste decomposition is an ideal and a safe disposal method, biological decomposition of segregated organic waste is more beneficial for solid waste management, as it easily converts waste to valuable fertilizer.
Two phase anaerobic digestion of artificially prepared MSW was carried out by coupling a solid-phase acidogenic system with an upflow fixed film reactor and also a suspended growth methanogenis reactor separately. The specially developed acidogenic culture was added to solid-bed and recycled back to the same to accelerate the bioleachate formation. A part of the Volatile Fatty Acids (VFA) bearing leachate from the acidogenic reactor was fed to the methanogenic reactor for methane production. Maximum cumulative VFA production was observed after 40 days of fermentation which corresponds to 73.45% of volatile solids reduction of MSW. However, maximum VFA concentration was about 11100 mg/1 as acetic acid. The performance of free cell reactor was compared with that of fixed film for the biomethanation of VFA. Fixed film reactor was found superior with respect to both BOD reduction and rate of gas production. In the fixed film reactor, 88.3% of BOD removal was observed at a loading rate of 1.48 Kg.BOD/cu.m-day.
In India, the collection, transportation and disposal of MSW are unscientific and chaotic. Uncontrolled dumping of wastes on outskirts of towns and cities has created overflowing landfills, which are not only impossible to reclaim because of the haphazard manner of dumping, but also have serious environmental implications in terms of ground water pollution and contribution to global warming. Burning of waste leads to air pollution in terms of increased TSP and PM10 emissions, which is equivalent to vehicular emissions at times.In the absence of waste segregation practices, recycling has remained to be an informal sector working on outdated technology, but nevertheless thriving owing to waste material availability and market demand of cheaper recycled products. Paper and plastic recycling have been especially growing due to continuously increasing consumption levels of both the commodities.Composting-aerobic and anaerobic, both the options are available to the country for scientific disposal of waste in future. However, country also needs something in terms of policy and guidelines to enable the municipal corporations to run the waste services efficiently.
Municipal solid waste (MSW) management practices in Kharagpur, a small city in West Bengal, India, were examined in detail and an integrated solid waste management plan proposed based on the study results. At present, the total solid waste generated in Kharagpur municipality is 95 metric tons/day, but the waste collected by the municipality is about 50 metric tons/day, which implies that almost 45 metric tons/day of the solid waste generated remains uncollected. Most of this waste is dumped on open land and in natural and engineered drains, thus blocking the flow of stormwater and contaminating groundwater. Other major problems include inappropriate bin locations and poorly designed community bins, collection vehicles that are in poor condition, inadequate labor for collection and transport of waste, and lack of waste treatment and disposal facilities.Twenty samples were characterized physically and their proximate analyses were done in the laboratory. The average values of various parameters were moisture content = 42.05 (±10.25) percent, total solids = 58.36 (±11.57) percent, volatile solids = 19.63 (±9.53) percent of total solids, fixed solids = 80.35 (±9.54) percent of total solids, organic carbon = 8.91 (±5.79) percent, COD = 0.158 (±0.08) mg oxygen/mg of SW and calorific value = 2391.16 (±264.58) cal/g (10,008.24 kJ/kg). MSW in Kharagpur has high moisture content and low calorific value, making aerobic composting the best treatment strategy. Composting can help to divert more than 80% of the total waste and will lead to enormous savings in costs of waste collection, transport and disposal. The remaining waste can be disposed off in an engineered landfill. Augmentation in labor and vehicle inventory has been proposed along with better treatment and disposal facilities.
This report proposes a new set of guidelines for the characterization of municipal solid waste. It is based on an analysis of reference methodologies, used internationally, and a case study of Valorsul (a company that handles recovery and treatment of solid waste in the North Lisbon Metropolitan Area). In particular, the suggested guidelines present a new definition of the waste to be analysed, change the sampling unit and establish statistical standards for the results obtained. In these new guidelines, the sampling level is the waste collection vehicle and contamination and moisture are taken into consideration. Finally, focus is on the quality of the resulting data, which is essential for comparability of data between countries. These new guidelines may also be applicable outside Portugal because the methodology includes, besides municipal mixed waste, separately collected fractions of municipal waste. They are a response to the need for information concerning Portugal (e.g. Eurostat or OECD inquiries) and follow European Union municipal solid waste management policies (e.g. packaging waste recovery and recycling targets and the reduction of biodegradable waste going to landfill).
Waste sorts were conducted during each of the four quarters (or seasons) of 1996 at the City of Columbia Sanitary Landfill. A detailed physical sampling protocol was outlined. Weight fractions of 32 waste components were quantified from all geographic areas that contribute to the Columbia Sanitary Landfill using a two-way stratification method, which accounted for variations in geographical regions and seasons. Comparisons of solid waste generated between locations and seasons were conducted at the 80% confidence level. The composition of the entire waste stream was 41% paper, 21% organic, 16% plastic, 6% metal, 3% glass and 13% other waste. Paper was the largest composition and glass was the smallest composition for all geographical regions. The result of this study was also compared with a 1987 Columbia, Missouri study conducted by EIERA (1987), with studies conducted in other states such as Minnesota, Wisconsin, Oregon and with national study conducted by the USEPA (USEPA 530-R-96-001, PB96-152 160. US Environmental Protection Agency, Office of Solid Waste, Washington, DC). The results of studies from other states are different from this study due to different local conditions, different methodologies and a different scope. There was a small (5%) increase in per capita weight from 1987 to 1996. The total per capita weight in the present study was 60% greater than the national per capita weight reported by the USEPA (1996) due to that the USEPA report excluded industrial, construction and certain commercial waste. The total per capita weight agrees with the national per capita weight for municipal waste reported by Tchobanoglous (1993), which included industrial, construction and commercial sources. The geographical and seasonal effects on the waste composition are evaluated and discussed. Statistical analysis indicates that waste characteristics are different among geographical regions and seasons. The potential for waste recovery and reduction is also discussed.
There has been a significant increase in municipal solid waste (MSW) generation in India during the last few decades and its management has become a major issue because the poor waste management practices affect the health and amenity of the cities. In the present study, various physico-chemical parameters of the MSW were analyzed to characterize the waste dumped at Gazipur landfill site in Delhi, India, which shows that it contains a high fraction of degradable organic components. The decomposition of organic components produces methane, a significant contributor to global warming. Based on the waste composition, waste age and the total amount dumped, a first-order decay model (FOD) was applied to estimate the methane generation potential of the Gazipur landfill site, which yields an estimate of 15.3 Gg/year. This value accounts to about 1-3% of existing Indian landfill methane emission estimates. Based on the investigation of Gazipur landfill, we estimate Indian landfill methane emissions at 1.25 Tg/year or 1.68 Tg/year of methane generation potential. These values are within the range of existing estimates. A comparison of FOD with a recently proposed triangular model was also performed and it shows that both models can be used for the estimation of methane generation. However, the decrease of the emission after closure is more gradual in the case of the first-order model, leading to larger gas production predictions after more than 10 years of closure. The regional and global implications of national landfill methane emission are also discussed.
A reliable estimate of the quantity of solid waste generation in the city is very important for proper solid waste planning and management. However, reported estimates of solid waste generation vary widely and lead to questionability. The reported values have been derived on the assumption of demography, standard rate of waste generation by households, density values, number of trucks engaged for waste transportation and monitoring of truck movement at dump sites, etc. This diverse nature of the available data and the question of accuracy necessitate a rigorous study that has tried to document the waste quantity in the recently formulated master plan of Dhaka City. The socio-economic parameters, behavioral characteristics, generation sources, seasonality, and per capita growth rate are considered in estimating the waste quantity along with its future projections. The findings from the estimation of waste quantities state that seasonal differences in the municipal solid waste stream are not substantial. The most seasonably variable material in the municipal solid waste stream is food waste. Residential waste is relatively homogeneous. Although there are some differences in waste generation depending on demographic and other local factors, most households dispose of essentially similar types of wastes. Variation occurs in waste composition dependent upon income levels and category of sources. Variation also occurs based upon the extent of source reduction and recycling opportunities. As opportunities exist to recycle wastes, the recycling facilities might have to grow at a similar pace to the generation of waste. Physical and chemical characteristics of solid waste are important to implement the waste disposal and management plan for the selection of resource and energy recovery potentials. A number of studies have been conducted to determine the composition of wastes including moisture content and calorific value. The data show that the moisture content in city waste is significantly higher and the calorific value is much lower, which determines the viability of composting or anaerobic digestions rather than waste combustion.