The below mentioned article will help you to prepare a project report on Solid Waste Management:- 1. Introduction to Solid Waste Management 2. Methods of Handling Solid Waste 3. Salvage and Recovery of Solid Waste 4. Process of Solid Waste Management 5. Objectives 6. Considerations 7. Deficiencies 8. Recycling of Waste Materials 9. Recycling of Plastics and Tyres 10. Plastics and Environment and Few Others.
Contents:
- Project Report on the Introduction to Solid Waste Management
- Project Report on the Methods of Handling Solid Waste
- Project Report on the Salvage and Recovery of Solid Waste
- Project Report on the Process of Solid Waste Management
- Project Report on the Objectives of Solid Waste Management
- Project Report on the Considerations for Solid Waste Management
- Project Report on the Deficiencies Associated with Solid Waste Management System (SWM)
- Project Report on the Recycling of Waste Materials
- Project Report on the Recycling of Plastics and Tyres
- Project Report on the Plastics and Environment
- Project Report on the Need for Proper Waste Management Programme
- Project Report on the Resources Conservation and Recovery
- Project Report on the Municipal Solid Waste Management Compositing Facilities in India
- Project Report on the Health Hazards of Landscape Pollution
- Project Report on the Management of Solid Wastes in Developing Countries
- Project Report on the Disposal of Hazardous Wastes
Project Report # 1. Introduction to Solid Waste Management:
Solid waste management can be divided into two major areas:
(i) Collection including storage, transfer and transport, and
(ii) Disposal, including any accompanying treatment.
The collection operation can be sub-divided into two unit operations, collection and haul. The collection operation consists of removing solid waste from the storage point. The haul operation includes the total round trip travel time (for the vehicle) from the collection route to the (waste) disposal site.
Three alternatives are normally considered for solid waste disposal:
(1) Direct shipment from municipalities to a sanitary landfill.
(2) Direct shipment from municipalities to a transfer station where solid waste is transferred to larger vehicles and then shipped for ultimate disposal.
(3) Direct shipment from municipalities to an incinerator where the solid waste is burned and the residue is shipped for ultimate disposal.
Solid waste management planning requires an assessment of many complex interactions among transportation systems, land use patterns, urban growth and development, and public health considerations.
Project Report # 2. Methods of Handling Solid Waste:
The physical nature of a waste may determine its handling characteristics.
The following are common handling methods:
(i) Solids, semi-solids, some wet materials, sticky, or tarry substances may be handled by front- end loaders or buckets.
(ii) Viscous liquids may be pumped by special pumps.
(iii) Liquids are handled by normal pumping equipment.
(iv) Packages may be handled in cartons, and
(v) Some materials are handled in fiber-pack drums.
Solid Waste Shredders:
Such machines can convert rubbish into a form more easily and economically handled for processing. Hammer mills in one adaptation or another, are the most commonly used size reduction machines.
Compactors:
Such machines can compact refuse. Hydraulic or pneumatic cylinders exert forces as high as 50 tons and reduce the original volume of refuse by 60 to 80%.
Incineration Equipment:
Solid and chemical wastes are often disposed of with the help of incinerators. Incinerators can be classified on the basis of burner chamber or fuel bed.
Common Practices for Solid Waste Disposal:
In most solid waste disposal methods, the main aim is to treat the refuse in such a way as to render it safe and sterile so that upon returning it to the environment, it will not pollute the air, water or land.
There are presently only three disposal methods which are practical for most industrial applications:
(1) Haulaway loose:
Waste is removed from plant for disposal by means such as landfill, incineration etc. Hauling away means exporting the refuse as loose material.
(2) Haulaway Compacted:
If the amount of refuse is large, refuse is compacted and then disposed off. It is a very popular waste disposal method for industrial installations.
(3) On site Incineration:
On site incineration is generally accepted as a good method for disposing of solid wastes. Industrial waste is burned efficiently and economically without polluting the air.
Project Report # 3. Salvage and Recovery of Solid Waste:
Many experts feel that the only lasting solution for the solid waste disposal problem lies in recycling and reuse of wastes (Fig. 33.3).
Waste processing has the following advantages:
(i) Added revenue.
(ii) Less waste to be disposed of.
(iii) Less transportation costs of waste.
(iv) Processed residue waste is put into a form which makes it suitable for land reclamation.
Steps involved in salvaging and recovery:
(i) Receiving the raw industrial waste and conveying it to a salvage-separation area.
(ii) Separating the salvageable materials from waste materials to be further processed.
Ferrous and nonferrous materials can be separated using magnets, cardboard and paper products can also be removed and placed onto the paper salvage conveyor for entry into the paper processing system.
(iii) Unsalvaged waste residue is conveyed to the main pulverizer unit,
(iv) Compaction system is employed to compact the pulverized residue for disposal.
Project Report # 4. Process of Solid Waste Management:
(a) Solid Waste Utilisation:
A developing country cannot afford wastage. By proper utilisation of solid waste a developing country like India can avail of many advantages, for instance.
(a) Waste utilisation directly or indirectly contributes to economic development.
(b) Waste utilisation generate employment opportunities.
(c) United solid wastes create environmental hazards by spreading diseases and causing air and water pollution.
(d) Waste utilisation helps to generate many useful products which are the basic necessities of life.
Resources recovery or waste utilisation is achieved by three techniques:
1. Reuse i.e. a given material has multiple uses.
2. Reclamation i.e. a component of the waste is recovered for use in a manner different from its original use.
3. Recycling i.e. isolating the material from which a given product was made and reintroducing it into the production cycle for production of the same product.
(b) Recycling and Reuse of Solid Wastes:
Recycling and reuse of the waste helps to reduce the problem of waste disposal. Resource recovery is a method to run wastes into resource recovering usable products- both materials and energy. As the disposal cost are expected to rise continuously due to increase in land price, and pollution controls, resource recovery is becoming more common and finding more favour.
About 70% by weight of municipal solids waste from domestic and commercial areas is combustible. But still only a small percentage of the resources is being recovered.
In some municipal solid waste processing facilities, the combustibles are separated from the non-combustibles. The combustibles are then shredded and burnt in utility boilers or industrial boilers as a primary fuel or as a supplementary to fossil fuel. This type of solid waste processing operation is known as a refuse derived fuel (RDF) system, RDF is used to supplement other fuel sources in a ratio of 20% RDF to 80% soils fuels.
It was reported that 29 RDF systems were operated in USA for power generation as early as in 1983. Processing 1250 to 18,000 tonnes of waste per week. Incineration and RDF technology seem to be competitive in cost. The plastic scrap or waste should be collected from the consumers or intercepted on its way from consumers to the municipal refuse site.
Project Report # 5. Objectives of Solid Waste Management:
The principal objectives of solid waste management to control, collect, treat, utilize and dispose of the solid wastes in an economical manner consistent with the protection of public health.
Project Report # 6. Considerations for Solid Waste Management:
The major considerations of concern with solid waste management apart from the economics are:
(A) Public health,
(B) Waste separation for recycling, and
(C) Energy recovery.
A. Public Health:
Under warm and moist conditions, and particularly with the help of vectors (carries) like water, air, food, rodents, mosquitoes and flies, organic solid wastes are ideal breeding places for pathogenic organisms.
Potentially hazardous substances like solvent and pesticide cans, medical wastes and asbestos debris present in solid wastes, air pollution from gaseous and particulate emissions from land fill sites and municipal incinerators, etc., also present some additional environmental concerns related to solid waste disposal.
Further, the solid waste management strategies should also take into account the possible deterioration of ground water quality because of land filling of solid wastes, residues from incinerators and leachates from the decomposing refuse.
B. Waste Separation for Recovery and Recycling:
Recovery and recycling of some of the resources in solid wastes, although a very appealing idea is rather difficult in practice. Expensive materials such as some metals are found to be economical to recycle by industries. Returnable bottles and refundable cans may be recycled from municipal wastes.
Separation of wastes at source is warranted and feasible only when the reclaimed materials find reasonable market. However, this concept of waste separation at source is receiving increasing attention in some developed countries due to the dwindling landfill capacity, economic incentives, improving markets for the reclaimed materials, environmental concerns and political will.
C. Energy Recovery:
Recovery of energy from municipal solid wastes can be achieved by the following two ways:
(i) Solid wastes can be burnt directly in incinerators or converted to more efficient “refuse-derived fuel” (RDF). Pyrolysis and anaerobic decomposition of organic matter in solid wastes are the other method’s available for recovering the fuel value of solid wastes.
(ii) Reuse of the recovered materials from solid wastes is the other principal mode of energy conservation. Obviously, mining and manufacture of ferrous and nonferrous metals starting from mining of the ores is so energy intensive that reuse of these metals is certainly justified from the stand point of energy conservation.
Project Report # 7. Deficiencies Associated with Solid Waste Management System (SWM):
(i) Rapidly Increasing Areas to be Served and Quantity of Waste:
The solid waste quantities generated in urban centres are increasing due to rise in the population and increase in the per capita waste generation rate. The increasing solid waste quantities and the areas to be served strain the existing SWM system.
(ii) Inadequate Resources:
While allocating resources including finance, SWM is assigned with a low priority resulting in inadequate provision of funds. Often there is a common budget for collection and treatment of sewage and SWM and the later receives a minor share of the funds. The inadequacy of human resource is mainly due to the absence of suitably trained staff.
(iii) Inappropriate Technology:
The equipment and machinery presently used in the system are usually that which have been developed for general purpose or that which have been adopted from other industry. This results in underutilization of existing resources and lowering of the efficiency.
A few attempts have been made to borrow the technology developed in other countries like highly mechanised compost plants, incinerator-cum-power plants, compactor vehicles etc. However, these attempts have met with little success, since, the solid waste characteristics and local conditions in India are much different from those for which the technology is developed.
(iv) Disproportionately High Cost of Manpower:
Mostly out of the total expenditure, around 90% is accounted for manpower of which major portion is utilised for collection. Since citizens tend to throw the waste on the adjoining road and outside the bin, the work of the collection staff is increased. Hence, the cost of collection increases considerably.
(v) Societal and Management Apathy:
The operational efficiency of SWM depends on the active participation of both the municipal agency and the citizens. Since the social status of SWM is low, there is a strong apathy towards it, which can be seen from the uncollected waste in many areas and the deterioration of aesthetic and environmental quality at the uncontrolled disposal sites.
(vi) Low Efficiency of the System:
The SWM system is unplanned and is operated in an unscientific way. Neither the work norms are specified nor the work of collection staff appropriately supervised. The vehicles are poorly maintained and no schedule is observed for preventive maintenance.
Due to shortage of financial resources, the vehicles are often used beyond their economical life resulting in inefficient operation. Further, there is no coordination of activities between different component of the system. The cumulative effect of all these factors is an inefficient SWM system.
Project Report # 8. Recycling of Waste Materials:
Crushing of materials.
Thermal deposition of waste organic in the form of gas and oil getting food sources as livestock from organic waste.
Melting plastic and moulding
Melting blast furnace slag for making artificial jewellery converting waste in solid fuel.
Compositing garbage and using as manure
Utilizing refuse for land fill
Materials products made from waste:
Water work silt
Red mud from Aluminium industries
Sugar factories waste
Agricultural waste: Paper, paper board, coconut, arece-nut, cashew-nut, fly-ash.
A tonne of solid waste processed by pyrolysis is believed to yield an energy equivalent of one barrel of oil. The city of Baltimore reportedly operated commercial scale facility in 1975 to produce 4.8 million pound of steam daily from the low-BTU gas generated by pyrolysis of municipal solid waste.
Thus saving of 357,000 barrels of oil annually was accomplished, in addition to the revenue earned from ferrous metals sorted out and the sale of glassy aggregate for use in cone race manufacture and street paving. Economic viability of full-scale commercial pyrolysis facility has still not been proved beyond doubt. The advantage of pyrolysis is that it produces a more generally useful and transportable form of energy.
Project Report # 9. Recycling of Plastics and Tyres:
Recycling of plastics may be carried out in any of the following ways:
I. Primary recycling where the same plastic product is manufactured again.
II. Secondary recycling where the material is reprocessed to a new product with different composition and in some cases may be inferior in properties.
III. Tertiary recycling where the plastic material is completely processed to a new form as in pyrolysis (where some chemicals are recovered). In USA, high density polyethylene bottles used for supplying milk, are collected from consumers and are converted to flake powder by grinding. This can be used for manufacturing plastic draintic drainage pipes or as inert fill material or an aggregate for low weight concrete.
Rubber Tyres Recycling:
Rubber tyres continue to pose disposal problems. They do not decompose well in landfills. Incineration of rubber must be done in specially designed facilities to check air pollution and to accommodate the intense heat produced by burning rubber.
The Kcal content of burning rubber is nearly equal to that of coal. Some systems burning rubber as fuel were successful. Production of fuels from rubber by pyrolysis was also successful. However, these were necessarily small-scale operations due to limited supply of tyres.
Project Report # 10. Plastics and Environment: To Be Or Not to Be:
Every citizen in India knows for sure, the fact that plastics have played a very vital role in the growth phase of the Indian economy during the recent past. Every vital sector of the economy starting from agriculture to packaging, automobile, building construction, communication or info-tech have been virtually revolutionised by the applications of plastics.
The plastic processing industry, which made a modest beginning during the 70’s, had really taken off only during the post-liberalization era. The current business environment and abundant domestic availability of plastic raw materials have resulted in a double-digit growth rate consistently during the recent years. Last year, the growth in polymer consumption was about 12 per cent.
Moreover, it is estimated that about Rs.20,000 crores has been invested in the last 3-4 years in this industry, leading to doubling of capacity. Continued growth in consumption at this rate would make India the 3rd largest polymer consumer in the world by 2010.
The Wonder Material:
This success story of Plastics would not have been possible but for the proven advantages that it possesses over its nearest substitutes like Metal, Glasses or Paper. Today the packaging industry is, by far the major user of plastics.
It constitutes 52% of the total consumption. They are used to pack cosmetics, toiletries, milk, edible oil and food products. Plastics in the packaging sector provide the convenience, ease of handling and packaging efficiency. It definitely increases the shelf life of food products.
In the transport sector, plastics are increasingly replacing or have replaced traditional material in automobiles, aircrafts and boats; for example, fibre reinforced plastics, fuel tanks, interiors, dash boards, bumpers and so on. In these applications, the functional superiority of plastics has been established.
The contribution of plastics as an aid to modern agriculture is immense. Drip and sprinkler irrigation systems, mulch films, green house films, pond and canal lining films are proven products to conserve water, protect crops from vagaries of weather, thus resulting in better productivity.
Plastics in Environment:
A few myths: In spite of its proven functional superiority, lately a few misconceptions are gaining ground, which are generating a feeling among the decision makers and the common public that plastics are harmful and should not be used.
If a ban is put on the use of plastics on emotional grounds, the real cost would be much higher, the inconvenience much more, the chances of damage or contamination much greater, the risks to the family health and safety would increase and above all the environmental burden would be many fold. Hence the question is not ‘Plastics vs. No Plastics’ but it is more concerned with the judicious use of plastics. The issue therefore has to be understood in the right perspective.
In the developing economies the rate of growth of consumerism is always high. This leads to a constant rise in the municipal solid waste. Plastics have the advantage of flexibility, strength, resistance to nature and being light weight. So, for packaging, plastics are the best solution. But that leads to higher generation of waste, which has to be managed.
The best way to manage this waste is to recycle it, as resources once generated from the petro oil do not go waste forever rather they come back into the system. We must adopt the slogan “We don’t waste-We recycle”. Though this problem needs to be addressed, the following facts and figures explicitly show how India is in the right situation to tackle this issue. Let us delve into the facts on the Indian dimension of plastic waste compared to the world average.
The per capita consumption of plastics in India is 3.5 kg as compared to the global average of 19 kg. The plastics present in the solid waste stream is 3 per cent in India as against 8 per cent world average. In spite of low waste volumes Indian plastic industry has taken initiatives on recycling which is about 60 per cent in India against the world average of 15-20 per cent.
Still, the often-repeated myths about plastics persist like-Plastics are toxic and are not safe for use, plastic wastes are eco-hazardous mainly due to non-biodegradability, plastics are harmful to plants and soil, plastic bags contaminate water, plastics are major source of waste problems and plastic bags choke drains during monsoon season.
Before any remark on alleged harmful effect of plastic is made, it is worthwhile to imagine an environment without plastics. Had there been no plastics and we were to use iron pipes for transportation of drinking water, nearly 40 per cent higher electrical energy would have been consumed due to pumping inefficiency and corrosion ; had there been no plastic milk pouches, chances of adulteration and related health hazards would have been multifold.
A Government of India Petrochemicals Industry Study states that change-over from glass bottles to plastic pouches results in a saving of 27.6 billion units equaling 4 X1000 MW thermal power in terms of energy consumption over a ten year period.
Had we used paper as the only mode of packaging, we would have cut 20 million trees matured over a period of 10 years, apart from generating highly toxic chemical pollutants that would have got discharged from the paper mill. The use of plastic creates for transportation, in fact, helps in controlling the denudation of forests.
CPMA has estimated that if plastics bags are used instead of jute bags for packaging of food grains and sugar; there would be an estimated saving of Rs.12,000crores, which is lost due to spoilage of food grains and sugar packed in jute bags.
Thus, in a nutshell, plastics have given us a risk free eco-friendly environment as it prevents wastage of food products. It does not generate pollutants during the manufacturing stage or the conversion process. It helps in conserving scarce natural resources and they are reusable and recyclable.
Reusability and recyclability are the two major attributes of any material to be regarded as ecofriendly. In advanced countries, though plastic waste contributes about 8 percent of total municipal solid waste, they have never banned plastics usage. They have gone for more pragmatic approach of proper waste segregation and recycling to make use of the recyclates in less value-added products, or incinerate to harness energy for further utility.
Project Report # 11. Need for Proper Waste Management Programme:
For an effective implementation of proper waste management programme, it is necessary to have holistic approach to tackle the issue. This would mean undertaking public awareness campaign, setting up of organized collection chain of plastics waste, incinerators or recycling units.
Instead of launching campaigns like “Ban Plastics” or “Use No Plastics” we must educate the people to propagate the avoidance of wrong littering habits among the public. We must have campaigns on “Ban Littering” and “Punish the Litterer”.
In any of these campaigns or establishment of disposal systems, the involvement of Government, industry and public is very important. In this context, it would be worthwhile considering the establishment of model cities for waste disposal system in major plastics consumption zones.
This system must encompass waste disposal, collection, segregation, processing and recycling, besides public awareness campaigns on wrong waste disposal habits and compliance to scientific disposal systems. The plastics industry must debate this concept to give it a final shape. These cities would act as models for others to emulate. We can also take a cue from the Western world on mechanised handling and disposal systems.
Another aspect which demands attention is establishing a centre for product development for recycled products and scientific waste management system, which can be a nodal institution for recycling and reusability of plastics. Because once we show the way to the people in the industry how they can profitably establish a unit for making different products out of waste, the magnitude of this problem can be reduced to a great extent. Polymer manufacturers including GAIL can extend their support to the industry in this regard.
Another important issue that is to be addressed by this industry is the bio-degradability of plastics. This is going to be a real challenge to the scientific community and any breakthrough in this area would be a real boon to the plastic industry.
It is appropriate here to quote an interesting fact from a study report published by International Energy Agency, Paris on carbon di-oxide emission. According to this study, the per capita CO, emission is 0.91 MT in India. It is 20.46 MT in USA and surprisingly it is the highest at 63.11 MT in Qatar, a small country.
The world average is 3.88 MT. definitely, we are far ahead, compared to other countries. There is tremendous scope to preserve our environment if we undertake scientifically planned preventive actions. The issue of environment has to be addressed with the right perspective by bringing in professionalism in our Environment Management Strategies. It demands as much attention as our business.
Project Report # 12. Resources Conservation and Recovery:
Many materials, such as steel scrap, which have been recycled for years are even more attractive with the increased cost of energy because greater power and fuel usage is required to produce virgin steel from the recycle scrap materials.
Recovery is Necessary:
1. For Reuse (conservation):
Direct reuse of the recovery by some treatment process that would convert it back into initial form.
Example:
The scrap automobile buses where scrap automobile is almost recycled to the basic metals from which it was made.
2. For Heat:
This might involve the recovery of heat from fossil fuel, generating systems, such as boilers furnace and ovens etc.
3. For other Purposes:
Waste material changed in character and is useful because of some reprocessing.
Metal Recovery:
It is possible to improve the separation of metallic wastes in a plant and also possible to reprocess with in the plant.
Ferrous Metal:
Separation of this material is easy because they are easily magnetically separated. The recycling of a ferrous material from a manufacturing facility is relatively straight forward since a company manufacturing equipment made of steel will have steel scrap for sell.
The material is put through a crusher where size reduction tends to make the particles more uniform. Large pieces of metal if malleable are normally sorted out on the feeder ahead of the crusher or put through an impact type crusher. The material is send to grinder and clean, free from nonmetallic waste, metal is found. It is then screened and finished high grade metallic product is found.
By recovering and recycling two important objectives are achieved:
(1) A valuable resource has been made available for reuse,
(2) A valuable space in a landfill.
Project Report # 13. Municipal Solid Waste Management Compositing Facilities in India:
Municipal solid waste management in India is becoming important in view of the fact that increasing amounts of solid waste generated in most cities is now being recognized as a major public health problem. Poor management of solid waste leads to problems, which transcend traditional environmental boundaries and contribute to air, water and soil pollution of the various technological solutions.
Compositing is being looked as one of the most suited solution in the hierarchy of integrated solid waste management programmes. Besides the various advantages which compositing methods provides, it faces several challenges which need to be addressed to use this technology without any environmental and health hazards in long run.
Dynamic changes occur in chemical composition during compositing process along with substantial changes in microbial populations and species abundance. As a result during compositing cycle some harmful gases are released in the atmosphere, which pose odour and health hazard in neighbourhood, and microbial contamination poses health hazard to workers.
Municipal solid waste management in India should be adopted with care and strict measures for safety of onsite workers. Proper maintenance of operational parameters should be ensured to minimize the health effect due to various gaseous emissions.
Down Stream Technologies for Waste Management:
The rapid industrialisation and increasing environmental degradation have necessitated development of effective waste management technologies. The downstream technologies are very effective in utilization of waste from process industries with nominal additional investment, value added products can be made using these wastes, which enhances the profit of the industries.
Present scenario is that most of the chemical and process industries are not having the downstream process for waste management. It is not the reason that these industries are unwilling to install such process, but such processes are not available for all the industries.
Some researchers have developed the processes for converting the low value streams into high value products. Ironically the industries are not coming forward to support such works by their active participation. Only joint efforts of the research institutions, consultants and industries would be able to solve this global problem in a betting economically and ecologically manner.
Cleaner Production Training:
The importance of training as a business environmental objective is recognized in the many environmental management standards being established around the world. The most important standard the ISO 14001 Environmental Management System (EMS) specification explicitly identifies training as one of the major components of a verifiable EMS.
The business managers who developed the standards are conducting cleaner production training in their own companies as a critical complement to their pollution control technologies. Without such training, the production employees are usually unaware of the high costs and risks of pollution control and they do not know the best strategies for reducing the environmental problems caused by the particular business processes on which they work.
Project Report # 14. Health Hazards of Landscape Pollution:
Improper handling of solid wastes is a health hazard especially for the workers who comes in direct contact with the wastes. During handling and transfer of biological wastes (from hospitals and clinics) disease transmission may take place by infection through open sores or vectors like rats and insects which invade refuse dumps for food.
Rats spread many diseases like plague, salmonellosis, endemic typhus, trichinosis etc. through direct bite. They quickly proliferate and spread to neighbouring areas destroying property and spreading diseases. Flies breed on refuse dumps, human faeces etc. from where they migrate to food and water and result in transmission of many diseases like bacillary dysentery, diarrhoea and amoebic dysentery in humans.
The improper disposal of hazardous wastes results in contamination of crops or water supplies and thus pose a serious health hazard for humans and animals resulting in acute effects like death.
Large scale epidemic of cholera, gastro-intestinal diseases, jaundice, hepatitis etc. result from contamination of soil and water bodies by the leachate from decomposed and purified garbage dumps. Chocking of drains and gully pits by the solid wastes result in water logging especially during the rainy season. This water logging results in breeding of mosquitoes in the stagnant water.
Project Report # 15. Management of Solid Wastes in Developing Countries:
Protection of the health and environment through the proper management of municipal solid wastes is beginning to gain importance in economically Developing Countries (DCs). Uncontrolled and improper management and disposal of municipal solid wastes and contaminated water sources are major threats to public health and environmental quality in DCs.
Although these threats are very real, pollution control and environmental improvement have been relegated historically to a low status in many DCs, while governmental policies emphasized industrial development.
Recently, however, environmental quality in most DCs has deteriorated to a level at which it can no longer be ignored. The result has been a substantial concern and intensification to efforts to find and apply means of reversing the deterioration and of raising environmental quality to an acceptable level.
Environmental degradation is especially serious and evident in the larger cities and their surrounding metropolitan areas. These areas have become overcrowded in the extreme, mostly due to the influx of migrants from the rural areas to the metropolitan centers.
This migration has taken place at a rate such that the capacity of municipalities to provide even the most basic of services is greatly exceeded. The problem is compounded by the fact that most of these cities have expanded their boundaries in an uncontrolled manner.
The explosive growth of the affected cities usually is characterized by the development of human settlements in the outskirts of the cities, as well as within the city boundaries in vacant lots, abandoned buildings, and similar areas. In the human settlement of these cities, water supply services are not available, and sewage and solid waste collection are nonexistent. Typically roads are unpaved and narrow, and accessibility for organized solid waste collection is difficult.
Basically, the typical situation in large municipalities of developing countries is one in which available resources (human, financial, etc.) are not sufficient to provide adequate municipal services to the mainstream of the population, or to those residing in human settlements.
Recently, the risks to the public health and to the environment in large metropolitan areas has become intolerable. Public officials recognize the risks and the close relation between pollution control and public health. Consequently, governments, in cooperation with some international lending institutions, have started to take steps to implement some measures of pollution control related to solid waste management.
Data Collection and Planning:
Two problems in particular are associated with data collection and planning in DCs: the lack of locally available trained personnel and the need for relevant data.
(i) Lack of Locally Available Trained Personnel:
Most universities and other education institution in DCs fail to offer curricula in solid waste management. This neglect results in a serious lack of trained human resources necessary for the planning and implementation waste management system. Consequently, DCs often times solicit and rely on the services of advisors from industrialized countries.
External advice will be of little utility unless the advisors are aware of the substantial differences in the social, cultural, financial, and environmental conditions and in the waste characteristics between DCs and those of the native country of the advisors. The reason is obvious— the conditions and waste characteristics are significantly different.
The result is that alternatives and technologies that are acceptable and practical in an industrialized country are seldom directly applicable to conditions in a developing country. Either the technologies must be modified, usually substantially, or they may in fact be completely incompatible. Efforts to directly transfer technology and practice from an industrialized nation to a DC usually do not meet with success and frequently fail miserably.
Such efforts generally are the result of a lack of understanding of the local conditions in DCs. An understanding of the conditions requires the collection of certain key data as well as a knowledge of the social, cultural, financial, and environmental conditions prior to the preparation of a plan of action.
(ii) Need for Basic Solid Waste Data:
Some of the required basic data are those that deal with quantity, composition, and characteristics of the waste generated in the developing country. In addition, information should be collected on current waste management practices in the DC, e.g., storage, collection, final disposal, availability of equipment, maintenance procedures, availability of human resources, budget, and sources of revenue. Preferably, these data should be collected by experienced and trained personnel.
If there is not sufficient time for collecting data in the field, then the data should be obtained from reliable sources and should be critically evaluated. A critical evaluation of data is extremely important because it enables a determination of the accuracy of the information and subsequently justifies any needed modification to the data as a consequence of the evaluation.
The characterization of the waste is an important element in the development of a realistic and sustainable solid waste management program. One reason is that successful management and processing of wastes depends on the types and composition of the material.
Waste generation rates and composition vary substantially among developing countries as illustrated by the data in Table 5.1. Wide variation are apparent from observation of the data in the table, for example, the percentages of paper, glasses; plastics/rubber/leather; and ceramics/dust/stones.
The substantial putrescible content of the wastes in DCs (22% to 75%) results in moisture contents and bulk densities of waste that are significantly greater than those encountered in most industrialised countries.
The bulk density of residential wastes in DCs varies from 11 to 24 I b/ft3. The average density of wet organic matter ranges from 30 to 35 1 b/ft3. Because bulk density is very sensitive to moisture content, care must be exercised in the collection and reporting of data concerning bulk density.
The desired level of detail regarding waste composition depends upon the type of treatment system to be used in processing the waste and the method of final disposition.
For example, in a developing country, the preparation of a waste management plan in which land filling would be the primary means of final disposal would depend mostly upon information on types (domestic, commercial, industrial, etc.) and quantities of waste to be disposed. A cursory knowledge of the composition of the waste would be sufficient.
On the other hand, a waste management plan in which resource recovery and recycling are key components would be greatly dependent upon detailed information regarding the characteristics of the waste (e.g. composition, bulk density and moisture content), as well as quantities.
Storage, Collection and Transport:
Although the utilization of data obtained in one region or country and application of the data to other regions or countries is technically inappropriate, some important similarities are evident in activities pertaining to storage, collection, and transport of solid waste.
The generalities presented are based on observations made by the authors in the course of studies carried out by them in several DCs in Asia, Africa, Central and South American, and in the Caribbean, as well as observations by others in various DCs. Since all observation pertain to DCs, no further reference to that fact is made in the discussion.
Storage Containers:
Containers used for storage of solid wastes are of many shapes and sizes, and are fabricated from a variety of materials. The type and applicability of the containers generally reflect the economic status of its user (i.e., the waste generator).
Types of containers include newspaper wraps, baskets, cardboard boxes, plastic bags, and metal or rigid plastic containers. The wide variety of container types and shapes commonly encountered within a community creates difficulty in establishing and operating an efficient solid waste collection system.
Several cities make use of communal containers (bins). The containers generally are constructed of metal, concrete, or a combination of the two. Communal containers may reduce the cost of waste collection, and can minimize problems associated with lack of storage space on site.
However, some problems are inherent in the use of such communal containers, including:
1. Depending upon the type of communal container, removal and transfer of the wastes from the container to the collection or transport vehicle may be difficult and time consuming.
2. If the bins are not emptied on a regular basis, the contents may be set on fire or illegal dumps may be established at the location.
3. Scavengers and animals may have access to the waste in the containers.
In human settlements, it is common practice to use two problems in particular are associated with data collection and planning in DCs: the lack of locally available trained personnel and the need for relevant data.
Collection and Transport:
A broad assortment of methods and equipment is used for the collection of wastes. The methods range from labor intensive to fully mechanized. Types of equipment and vehicles extend from simple hand-drawn wagons or bins to modern waste collection vehicles.
The typical collection crew consists of three or four workers, although crews of as few as two or as many as eight have been observed. In some instances, the crew may be augmented by unauthorized individuals who take part in the collection activity in order to scavenge materials from the wastes. The usual situation is that the collection activity is characterized by excessive handling and use of inefficient methods.
Compactor trucks, both of the rear and front loading variety, are found in many countries. Unfortunately, the use of such trucks is becoming increasingly popular, despite the fact that generally little, if any, additional compaction occurs in the vehicle because the loose wastes have a high bulk density.
Furthermore, some complex features and consequences are associated with the use of compaction vehicles some of which may not be evident or considered at the time that vehicle is purchased.
They are:
1. The need to adequately match compaction chamber to the truck chassis.
2. The possibility of the weight of the truck (and its load of waste) exceeding the bearing capacity of roadways.
3. Inaccessibility of the vehicle to remote areas and narrow streets.
4. The requirement for adequate facilities and trained personnel to conduct complex repairs and preventive maintenance, particularly of the hydraulic system; and
5. The need for a readily-available source of spare parts to maintain the regularity of the collection service.
Although preventive maintenance is necessary to maintain a collection fleet in proper operating condition, neglect of preventive maintenance is a common situation in DCs. Maintenance generally takes place only after a catastrophic failure of the vehicle or its equipment. A carefully planned maintenance program minimizes catastrophic failures and prolongs the life of the equipment.
A maintenance program is of significant importance since collection and transport account for a large portion of the total cost of the waste management system. Due to lack of maintenance programs, those responsible for dispatching the vehicles to their respective routes commonly are not aware of the exact number of vehicles at their disposal of a given day.
Frequency of collection varies from daily to monthly. In some cases, waste collection is provided only on special occasions, such as during cleaning campaigns.
Collection routes very rarely are firmly established. On the contrary, a common practice is to leave the decision for the route to the discretion of the driver. Therefore, it is not unusual for a truck to arrive at the disposal site only partially loaded due to inefficient routing.
Usually, after it has been loaded to capacity of the collection route has been covered, the loaded collection vehicle is driven directly to the disposal site. In some cases, an indirect route is taken to the disposal site in order to have an opportunity to discharge a part of, or even the entire, load for use as animal feed or for recovery (salvage) of materials that have some monetary value.
Resource Recovery:
In this discussion, the term “resource recovery” is applied to the reclamation of resources (materials) discarded as wastes, and to the institutional arrangements leading to resource recovery (e.g., scavenging, governmentally or industrially operated enterprises). Scavenging is recovery of materials by entities not sanctioned officially by the government.
The following three factors generally contribute to the practice of resource recovery in DCs:
1. Materials and Energy Conservation:
Shortage of raw materials essential to local industries, lack of affordability or production capacity for items that can be remedied by recovery of useable materials from wastes, and shortage or expense of energy.
2. Economics:
Underdeveloped economy of the country.
3. Conservation of Soil Resources:
Local soils that are of poor quality or are being rapidly deprived to organic matter. Two of the beneficial characteristics that make resource recovery an advisable policy for developing countries are that it generally catalyzes the development of organized, systematic waste management and that it reduces the amount of wastes requiring disposal.
In addition, resource recovery provides a livelihood for a relatively large number of individuals in the lower economic sector. Finally, some of the revenue obtained from the sale of the materials can be used to defray a part of the cost of waste management, if the system is properly planned implemented, and administered.
1. Materials and Energy Conservation
Most DCs are lacking in one or more of the primary (raw) materials (e.g., iron ore, bauxite, or petroleum) which are important for economic development. The importance and relevance of this situation is that if a satisfactory substitute cannot be found, the complete depletion of a raw material marks the termination of all manufacturing and usage based upon that material.
Furthermore, even though potential substitutes may exist, the may lack an important property or characteristic. For example, they may not be as durable, or they may not possess suitable thermal properties. Even a suitable substitute is subject to eventual depletion. For example, plastics are manufactured primarily from depletable fossil fuels.
In many cases, the establishment of a resource recovery program can postpone depletion or contribute to industrialized development by supplying secondary materials to existing or new manufacturing industries. Materials that can be (and are) recovered from solid waste and recycled into primary manufacturing industries include some of those listed in Table 5.1, namely paper, metals (especially aluminum and steel cans), and plastics.
Energy recovery can be practiced using one of two methods. One method is to recover and recycle materials that can be substituted for those that require a substantial amount of energy to process and manufacture into consumer products (i.e., energy-intensive material). The second method is to convert the chemical energy of waste into a usable form (e.g., through bio-gasification, thermal conversion, etc.)
2. Economics:
The economy plays a key role in all aspects of resource recovery. Since the economic situation in most DCs leaves them with little capital for the importation of primary (raw) materials, one alternative is to conserve primary materials by recovering and recycling materials manufactured from them.
This approach is worth consideration and implementation despite some reports that indicate that recycling a material would be more costly than importing it. Careful analysis of such reports shows that in most DCs, the findings and conclusions are based on questionable assumptions and on a short-term outlook rather than on a long-term horizon.
3. Conservation of Soil Resources:
The majority of developing countries have a strong dependence on agriculture for subsistence as well as economic growth. Consequently, conservation and restoration of soil quality and maintenance of soil productivity are important concerns.
Two of the main causes of loss in the quality, and therefore productivity, of soil are erosion and inadequate organic matter content. Erosion removes the top, productive layers of the soil and leaves an exposed layer that is basically devoid of plant nutrients. In addition, the structure of the exposed layer is such that it impedes plant growth and is resistant to tilling.
The organic matter in the soil provides plant nutrients and imparts a wide range of well- known, desirable characteristics to soil. However, since organic matter is transformed continually when cultivated, it must be periodically replenished.
The organic matter in solid waste, after having been adequately recovered and converted, can serve as a replacement for the lost organic matter in soil. Putrescible material such as food preparation residues and market waste, which are prevalent in the solid waste of most DCs as indicated in Table 1, are readily convertible to soil amendment (through composing/or example), although this is not a common practice in DCs.
Implementation of Resource Recovery:
Resource recovery from solid waste can be implemented at two levels:
Level 1:
Manual recovery by individuals (scavengers) prior to collection, to treatment, or to disposal of the solid waste.
Level 2:
A combination of manual and mechanized recovery conducted on a relatively large scale and according to a governmentally sanctioned plan of operation.
The term “scavenging” usually is applied to the first of the two levels of recovery. The second level is typically termed, “conventional resource recovery”.
Scavenging:
Level 1:
Scavenging is well established in DCs. In fact, it is so well entrenched that attempts made to abolish the practice in a few DCs have been met with strong resistance. Some scavengers are referred to as “itinerant” because they roam the streets looking for items that can be re-used. Other scavengers limit their activities to the collection of one or two materials (e.g., paper, metal objects).
Generally, scavengers have an arrangement with a “middle-man”. The middle-man is an individual who : 1) has the contacts with the end-users; 2) can package and sell the quantities of materials desired by users; and 3) provides the scavengers with compensation and perhaps a collection vehicle (e.g., a cart or tricycle). In some locations, the solid waste collection crew conducts its collection activities as well as some scavenging of materials.
Generally, the family and social backgrounds of scavengers are such that scavenging is the only option available to them to earn a living. In many cases, scavengers have two choices-scavenge or starve. The work of a scavenger is arduous and has little reward.
Scavengers can work up to 12 hours each day in order to earn money sufficient only to survive. In addition, scavengers often live at or in the vicinity of the final disposal site, (dump site) under unhealthy conditions.
Acceptance of scavenging by modern society varies from complete rejection to indifference. However, in most developing countries, scavenging is an important element in the economic survival of a number of industries (e.g., pulp and paper mills). Despite its detraction, plausible reasons exist for allowance and maintenance of scavenging.
Based on some studies conducted by the authors, scavenging should not be banned without providing alternative means of supporting the displaced scavengers and without taking the necessary steps to avoid, or at-least reduce, any adverse impacts on industrial activity and the economy.
Mechanized Resource Recovery:
Level 2:
Complex, mechanically-intensive resource recovering facilities require a well- trained work force and sophisticated control systems, requirements that generally do not conform to the situation in DCs. Thus, it is disconcerting and unfortunate to observe the trend among some of the larger cities in developing countries that are attempting to implement complex resource recovering technologies.
These technologies are usually transplants from industrialized countries; that is, they are direct transfers of technology. Unfortunately, these directly transferred technologies generally cannot succeed without modifications based on the waste characteristics of DCs, extensive maintenance programs, and ready access to capital for spare parts, among other requisites.
Examples of some directly-transferred technologies include incineration system, refuse- derived fuel systems, and in-vessel compositing. The degree of success of incineration systems is highly dependent on the dry, combustible content of the solid waste. Such content is fatally low in many developing countries, where the waste has a high moisture content, and supplemental fuel would be requires to sustain combustion.
Hopes for successful implementation of complex, highly mechanized systems for compositing almost inevitably are dashed by the failure of the composite system to perform adequately (due to low yields and high operating costs) and by unrealistic expectations with regard to markets and prices for the finished composite.
Some of the more important conclusions that can be drawn from the record of unsuccessful attempts at direct transfer of resource recovery technology to developing countries are the following:
1. Complex and maintenance-intensive resource recovery operations generally are not feasible in developing countries (at least until the level of expertise and waste characteristics indicate that more complex technological solutions are worthy of consideration).
2. Waste reduction, source separation, recycling, and the use of processes which use a combination of manual and minimal mechanical segregation are feasible approaches.
3. The capacity and willingness to pay for the construction, operation, and maintenance of a particular technology should be among the first issues addressed when considering implementation of a complex resource recovery system.
Final Disposition:
Most municipal solid wastes generated in developing countries are disposed in open dumps. Most of the open dumps lack of the proper equipment and trained personnel necessary for conducting the operation in a manner such that the public health and the environment are protected. There are very few modern sanitary landfills in developing countries, and most of them “sanitary” only in name.
Since few resources usually are devoted to final disposal, the operation of the dump sites simply consists of discharging the wastes-and spreading them upon the land in a uncontrolled fashion and without modern construction methods (e.g. small working face, bottom liner and leachate control system, and landfill gas control system).
Costs:
The poor and inadequate management of municipal solid wastes in developing countries leads to relatively high costs for the services provided. It has been demonstrated that the costs associated with waste management can account for as much as 30% to 50% of the entire municipal budget.
In addition, in some cases, it is apparent that the management of solid waste is frequently used to meet political objectives. For example, a substantial labour force for waste management beyond the size that normally would be required may be approved to gain political favour.
Since the monetary expenditure for providing the service involved in waste management is high, the municipality generally must subsidize a large percentage of the cost. Waste generators seldom pay service fees.
Finally, key reasons for the inordinately high cost of solid waste management in developing countries are lacking a shortage of trained personnel and the absence of adequate and comprehensive planning.
Project Report # 16. Disposal of Hazardous Wastes:
Important sources of commercial hazardous waste as:
(i) Hospital injections or anatomic waste, sharp, chemicals, like solvents or liquid developed, expired unused and contaminated drugs or other vaccines,
(ii) Industry – Typices treatment methods and
(a) Chemical and physical treatment methods – emulous separation distillation, detoxification, naturalization.
(b) Thermal Treatment includes physiolysis and incineration pyrolysis is applied seldom. The main advantage is the ruler smell volume of gas which has to be cleaned the disadvantage is that the sepase time the decomposition gas and vapours is so experience that the surplus proceed do us. Compete the effort the gas is used as fuel gas sot that in most case direct combust ion is prepared.
(c) Dumping is the only method of disposal when the substance cannot be destroyed by incineration. Dumping is carried out by ground level dumping or underground reposition sealing system is must the largest is to avoid the penetrate on of rain water in to the deep and the pollution of ground water by leach it plants C peeling combined with minaret drainage layers and mineral selling layers and melance at surface and bar.