Solid Waste State and Impact
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of solid wasteStatus of Solid Waste management
Generation
and characteristics of solid waste
* Agricultural wastes
The major waste and residues from agriculture are animal
manure from the farmers' houses, the crop residues as well as residues of
agro-chemicals.
Manure wastes are generated from pigs, cows, and buffaloes:
the quantum of these wastes has not been estimated yet because these are
recycled in-situ.
Crop residues are mainly from coffee, rubber, tobacco, and
coconut plantations: The
quantity of such wastes has not been estimated as yet for the whole
country.
The application of agro-chemicals is increasing. However the
concentration of agro-chemicals in soil is still lower than the
permissible limit.
*
Municipal
wastes
Solid waste is generated from several major
sources:
-
House
hold waste: generated from living activities
-
Industrial
waste: including, hazardous waste due to the processing activities in the
factories and other manufacturing units.
-
Clinical
wastes: generated from activities of hospitals and
clinics.
-
Sewerage
and sludge from municipal sewer systems
-
Commercial
wastes from restaurants and business areas
-
Construction
and demolition debris from construction and rehabilitation
works
The generation rates of solid waste depend on the category
of urban area and range from 0.35 kg/c.d. to 0.80 kg/c.d.
The average quantity of solid waste generated from towns and cities was 16,237 tones/day in 1996 and 19,315 tones/day in 1997. This figure increased to 22,210 tones/day in 1998. The collection efficiency was 40 - 70 % of generated wastes in big cities and 20 - 40 % in small towns. The amount of sewage sludge received for dumping into landfill everyday was estimated at 822 tones/day.
Specific gravity of solid waste plays a decisive role in
choosing the collection equipment and transport modes. It ranges from 400 - 580
kg/m3 such as in Ha Noi, Da Nang: 420 kg/m3; Hai
Phong: 580 kg/m3; Ho Chi Minh City: 500 kg/m3.
Composition of urban solid waste is very diverse and is
characteristic for each town (living custom, civilisation level, and
development rate). Generally there are some common characteristics as
follows:
-
Composition
of organic origin accounts for high rate (50.27% -
62.22%);
-
Contains
a lot of soil, sand and fragment of brick, stone,
etc;
-
High
moisture content, low specific heat energy (900
Kcal/Kg).
Solid waste analysis in composition plays an important role
in selecting treatment technology.
Changes in composition of domestic waste in Ha Noi from 1995 to 1998 are shown in
Composition of solid waste in several cities in Vietnam in 1998 [6]
%
in weight
|
No. |
Composition |
Ha
Noi |
Hai
Phong |
Ha
Long |
Da
Nang |
Ho
Chi Minh City |
|
1 |
Organic
compounds |
50.10 |
50.58 |
40.1-
44.7 |
31.50 |
41.25 |
|
2 |
Plastic,
rubber, leather |
5.50 |
4.52 |
2.7
- 4.5 |
22.50 |
8.78 |
|
3 |
Paper
in all kinds |
4.20 |
7.52 |
5.5
- 5.7 |
6,81,400 |
24.83 |
|
4 |
Metal |
2.50 |
0.22 |
0.3
- 0.5 |
1.40 |
1.55 |
|
5 |
Brick,
stone, ceramics |
1.80 |
0.63 |
3.9
- 8.5 |
1.80 |
5.59 |
|
6 |
Soil,
cobble, and other solid matters |
35.90 |
36.53 |
47.5
- 36.1 |
36.00 |
18.00 |
|
Water
content Ash
content Density,
ton/m3 |
47.7 15.9 0.42 |
45
- 48 16.62 0.45 |
40-
46 11.0 0.57-0.65 |
39.05 40.25 0.38 |
27.18 58.75 0.412 | |
Source:
Report " State of Environment in Vietnam" - 1999 -
NEA
Collection, storage and
disposal
*
Collection and transportation: In general, solid wastes are
not segregated at source. They are collected together and transported to
the treatment sites. The collection efficiency is 40 - 67 % of generated
wastes in big cities and 20 - 40 % in small towns. Average collection rate
is only about 53.4%. There is still inconsistency in technology for
collection and transportation, with a mix of different
forms:
Solid
wastes from streets and public locations are collected manually, using
manual sweeping and loading into handcarts for transportation to transfer
stations;
Solid
wastes from households are collected by handcarts or waste collection
vehicles running through streets according to a planned
schedule;
Solid
waste from hospitals, business and industrial centres and construction
sites are collected and transported under specific
contracts.
*
Treatment and disposal of solid wastes: Most
solid waste is disposed at open landfill sites. The rate of recovery for
recycle and reuse is around 13 % -20 %, mainly done by scavengers, who
collect plastic, paper, metal and glass. Recovery rate of solid waste from
sources to treatment location is rather high. However, waste picking
activities are completely spontaneous without any form of organisation and
management.
About
1.5 % - 5 % of the total generated wastes are recycled by composting to
produce fertilisers and soil conditioner.
The
existing landfill sites are not controlled for hazardous matter, stinking
smells and leachate, which are potential sources of pollution for land,
water and atmosphere.
Landfill
sites of urban areas in the Mekong Delta are still suffering from flooding
in rainy season, which may lead to unexpected negative impacts to the
environment.
The
sanitary landfills are required for environmental protection, as there is
no liner in the bottom and on the walls, no leachate collection and
control or gas system, and no cover layer and no fence on traditional
landfills.
The
toxic wastes from hospitals and industries are not treated before dumping
with domestic waste at the landfill.
Several hospitals have installed incineration system to treat
medical hazardous waste. Two incinerators are used for treatment of
residues from shoe manufacturing industries with a capacity of 16
tons/day.
* Critical problems and short
comings
The key issues of solid waste management in Vietnam are shown in
Key issues of solid waste management in Vietnam
|
Component |
Key Issue |
|
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Strategic Framework |
Current investment in waste management services
and facilities is constrained through lack of available
finance.
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The operational budget for waste management
services is presently insufficient to ensure a fully effective and
sustainable service. |
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Specific responsibilities within waste
management sector have not been clearly defined and, as such,
development of improvements to the service is being hindered. |
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There is presently insufficient socialisation
(involvement of the community and increased public private
partnerships) in waste management services. |
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There remains a need for increased training and
capacity building programs within the waste management sector. |
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Waste Treatment and Disposal |
There is at present lack of sustainable
investment in waste disposal facilities. |
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Operation and management of current waste
disposal sites are inadequate to ensure that on going environmental
and public health protection measures and mobilisation of increased
operational budget is necessary. |
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Completed waste disposal sites lack agreement
on, and implementation of, closure plans. This
would be required to ensure effective environmental and public
health protection measures are in place. |
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Lack of proper waste treatment facilities as
well as management skills at the landfill sites. |
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The informal waste recycling sector is active
both at source and at final disposal points but health and safety
provisions were low in this sector. It caused high risks for public
health to the people. |
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Cost Recovery |
There appears to be opportunities for increased
socialisation of some services such as waste collection to help
improve cost efficiencies. |
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Cost recovery and fee collection is presently
low.
Improved cost recovery would assist the development of waste
management services. |
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Public Awareness and Education |
The level of public awareness of environmental,
health and safety issues of waste management issues appears to be
relatively low. |
There is no classification of hazardous waste in
Vietnam. Most hazardous wastes are not treated or are treated in a very
primary way and then dumped together with municipal wastes at landfill
sites.
The daily
production of hazardous waste from hospitals is estimated at about 50 - 75
tones (comprising 22 % of hospital waste). Medical Waste composition from
different regions in Vietnam- 1998 is shown in table 6.3.
Average bulk density of the hospital waste is 150
kg/m3; Water content is 42%; Calorific
value is 2,150 kcal/kg.
Medical waste composition in Vietnam
|
Hospital Waste Composition |
Ratio (%) |
Containing Hazardous Materials or not? |
|
Organic waste |
52.9 |
No |
|
PP, PE, PVC bottles and bags |
10.1 |
Yes |
|
Bandage, plaster |
8.8 |
Yes |
|
Metal, cans |
2.9 |
No |
|
Glass, syringes, medicine tubes |
2.3 |
Yes |
|
Syringes and syringes needles |
0.9 |
Yes |
|
Waste paper, cartons, paper |
0.8 |
No |
|
Human parts for lab analysis |
0.6 |
Yes |
|
Soil, cobble, china, and other solid
matters |
20.9 |
No |
|
Total |
100.0 |
|
Total
of Hazardous Items |
22.6 |
|
Source: Report on " Medical Waste Management "
by Ministry of Health (MoH) - 1998
According
to statistical data in the four big cities, Ha Noi, Hai Phong, Da Nang and
Ho Chi Minh city, the amount of industrial solid waste is about 15 - 26 %
of municipal solid waste. In the industrial solid waste, about 35 - 41 %
of solid waste are hazardous. Composition of industrial solid waste is
very complex, depending on the raw materials, technological processes and
final products of each production centre and its related services.
The daily production of hazardous waste from
industries in 1997 is roughly estimated at about 1,930 tones/day
(comprising 19 % of industrial waste) This figure increased to 2,200
tones/day in 1998 and 2,574 tones/day in 1999.
The hazardous waste generated from major industrial sectors in several cities in 1998 is shown in
Generated industrial hazardous wastes in several
cities in Vietnam (Ton/Year)
|
Provinces/City |
Electrical/ Electronic |
Mechanical Industries |
Chemical Industries |
Light Industries |
Food Processing |
Others |
Total |
|
Ha Noi |
1801 |
5005 |
7333 |
2242 |
87 |
1640 |
18108 |
|
Hai Phong |
58 |
558 |
3300 |
270 |
51 |
420 |
4657 |
|
Quang Ninh |
- |
15 |
- |
- |
- |
- |
15 |
|
Da Nang |
- |
1622 |
73 |
32 |
36 |
170 |
1933 |
|
Quang Nam |
- |
1554 |
- |
- |
10 |
219 |
1783 |
|
Quang Ngai |
- |
- |
- |
10 |
36 |
40 |
86 |
|
Ho Chi Minh City |
27 |
7506 |
5571 |
25002 |
2026 |
6040 |
46172 |
|
Dong Nai |
50 |
3330 |
1029 |
28614 |
200 |
1661 |
34884 |
|
Ba Ria - Vung Tau |
- |
879 |
635 |
91 |
128 |
97 |
1830 |
|
Total |
1936 |
20469 |
17941 |
56261 |
2574 |
10287 |
109468 |
Source : Report "Statistics and prediction of generated hazardous wastes and Recommendation for Master Plan of HW treatment plants in Vietnam" by Centre for Research- Investment Consult for Rural Development, 1999.
Environmental Impacts of Solid Wastes
There are major industries, which may cause problems
for air quality. They are mechanical, electronics, chemicals and chemical
fertilisers. Resulting from measured data, the typical sources of air
pollutants from several industrial activities are shown in table 6.4.
- Concentration of C6H9OH was 2,5 - 9 times higher than
permissible value
- Concentration of As2O3 gases was 12 times
higher than permissible value
- Concentration of H2SO4 was 2
times higher than permissible value
Impacts
on soil and water quality
The sludge from wastewater treatment plants or
drainage system from industries contains high concentration of heavy metal
and inorganic matters. The characteristics of sludge are varied but less
toxic than liquid form. Besides sludge generated from treatment system, a
large quantity of toxic matter is produced from processes such as antimony
(Sb), battery, oil wastes etc. All these kinds of wastes are not treated
in proper ways. The toxic materials are dissolved into underground water
causing pollution in underground water.
In addition, the hazardous and toxic waste from industrial activities that is dumped into unhygienic landfills also causes negative impacts to the environmental quality, as well as directly impacts on public health.