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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 http://dx.doi.org/10.1680/warm.2011.164.4.247
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
g
1Sandip Tanaji Mali ME
Assistant Professor, Sinhgad College of Engineering, Pune,
Maharashtra, India
g
2Kanchan C. Khare PhD
Professor, Sinhgad College of Engineering, Pune, Maharashtra, India
g
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
5
m
2
) 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: www.mapsofindia.com
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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
2
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
2
) and nitrogen oxide (NO
x
) at the disposal site
was 1708.3mgm
3
, 285.33 mgm
3
and 234.07 mgm
3
respec-
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
condition.
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,
2001).
(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
3
(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
3
.
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
Series
No.
Waste composition
category
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,
grass
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
(4.38).
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
Series.
No.
Sampling
date
Sample
No.
Plastic
a
Paper
b
Cloth
c
Metal
d
Stone
e
Glass Organic
f
Total
1 26/1/2008 1 5.29
.00
.40
.00
.00
.085
.4 100.0
227
.45
.110
.91
.611
.90
.063
.1 100.0
333
.66
.92
.10
.015
.00
.072
.4 100.0
4 16/2/2008 1 9.09
.62
.61
.14
.31
.072
.4 100.0
528
.69
.87
.70
.43
.51
.468
.8 100.0
6 30/3/2008 1 7.54
.03
.50
.711
.40
.072
.9 100.0
723
.48
.28
.90
.018
.30
.061
.2 100.0
834
.96
.80
.60
.08
.20
.079
.5 100.0
9 13/4/2008 1 7.59
.05
.91
.514
.32
.459
.4 100.0
10 2 5.74
.54
.00
.512
.25
.267
.9 100.0
11 3 9.85
.84
.00
.913
.30
.765
.5 100.0
12 29/5/2008 1 5.86
.720
.20
.01
.62
.563
.2 100.0
13 2 11.011
.89
.80
.01
.40
.066
.0 100.0
14 3 7.67
.915
.40
.03
.00
.965
.3 100.0
15 19/7/2008 1 2.44
.15
.21
.31
.80
.384
.9 100.0
16 2 5.34
.68
.21
.22
.00
.678
.1 100.0
17 19/8/2008 1 6.724
.716
.80
.72
.72
.546
.0 100.0
18 2 17.34
.514
.60
.52
.34
.756
.2 100.0
19 3 19.34
.316
.40
.62
.20
.457
.0 100.0
20 28/9/2008 1 4.82
.34
.90
.75
.50
.980
.9 100.0
21 2 9.01
.22
.80
.65
.71
.379
.4 100.0
22 19/10/2008 1 2.74
.56
.31
.17
.61
.176
.8 100.0
23 2 2.87
.75
.70
.87
.01
.374
.8 100.0
24 9/11/2008 1 3.43
.68
.81
.811
.31
.469
.8 100.0
25 2 5.85
.411
.21
.08
.61
.266
.8 100.0
Mean 7.16
.97
.80
.77
.01
.269
.3 100.0
std dev. 4.14
.55
.40
.65
.21
.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
Series
No.
Sampling
date
Sample
No.
pH Density:
kg m
3
Moisture
content: %
Organic
matter
Total
solids:
%ofTS
Volatile
solids:
%ofTS
Fixed
solids:
%ofTS
C: % N: % C/N
1 26/1/2008 1 7.9 786 58.91 44.54 83.34 51.94 48.06 12.80
.621
.33
227
.3 725 43.67 35.17 73.13 57.51 42.49 9.40
.53 17.74
337
.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
528
.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
727
.8 945 43.37 37.25 69.72 57.31 42.69 15.36 0.89 17.26
837
.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
.44
.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
.43
25 2 7.7 710 46.06 18.52 68.80 73.79 26.21 7 0.18 38.89
Mean
std dev.
7.85
0.37
854.96
212.868
48.088
5.29
32.836
8.85
70.28
6.32
62.6144
7.92
37.3828
7.92
11.62
4.77
0.5
0.24
20.09
4.38
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
.3
2 Paper: % 5 1.98 6
.9
3 Rubber, leather,
synthetics: %
NA 0.4NA NA
4 Plastics: % 5 2.37 7
.1
5 Clothes: % NA 1.2NA 7
.8
6 Glass: % 10 1.16 1
.2
7 Metal: % NA 0.94 0
.7
8 Inert matter: % 15 40.65 7
9 Density: kg m
-3
NA 437.00 NA 854.96
10 Gross calorific value:
kcal kg
-1
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
Compostable
Recyclable
Inert
Jan. Feb. March April May July Aug. Sept. Oct. Nov.
Month (
y
ear 2008)
Percentage
100
90
80
70
60
50
40
30
20
10
0
Figure 4. Variation of physical composition of MSW
253
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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
2
, 103.28 km
2
and 98.04 km
2
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
area.
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
1999
2001
2006–07
2008
Com
p
onents of MSW
Percentage
75
70
65
60
55
50
45
40
35
30
25
20
15
10
5
0
Figure 5. Variation of MSW composition with time
254
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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
strategies.
(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.
Acknowledgements
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
256
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