4 Traditional methods of waste collection and disposal

Dr. P. Sivashanmugam

Objectives:

After completing this module, you should be able

• To understand the problems of waste generation
• To identify the need for waste collection
• To identify the various waste disposal methods used in old times

Introduction:

The problem of waste generation is as old as the advent of human life. With time there has been evolution in the living pattern of humans and so has in the quantity and quality of waste generation. Earlier, the kind of waste generation was mainly biodegradable but gradually the wastes have been transformed to recalcitrant and toxic. During prehistoric times, human lived in a group like nomad and the waste they generated were degraded by the scavengers. The waste such as weapons, bones and stone tools (non biodegradable) never accumulated to the level to pose problem. The general method employed for the management and disposal of waste was open dumping. Open dumping is still practised widely as it is easy and cheap method.

During ancient civilization, there was no organized waste management system, people used to litter waste anywhere and in case of odor problem, they covered the waste with clay. The early history of waste dumping system can be traced back to 500 BC in Greece, where people first created town dump. The Greeks by law were directed to dump waste one mile from the city. During same time, Athens law prohibited littering of waste on the streets. The Egyptians on the other hand, dumped garbage in the river Nile. During 2nd century BC, the Chinese people had systematic workforce for organized cleaning of major cities. The Mayans in ancient times had proper waste disposal system, where they had special dumps for organic waste and reused materials like broken earthen pots. Industrial revolution accompanied major change in waste quality and quantity. Europe in 18th and 19th century saw widespread occurrence of epidemics due to industrial waste and human waste. The Americans generally collected waste in huge bags and dumped in sea.

In this module the following topics are discussed in brief

Need for collection of solid waste Disposal of solid waste

Need for collection

Effects of improper collection or no collection of solid waste from the environment

(i) Effects on human health

Organic constituents of solid waste have tendency to degrade easily and during the process creates foul odour because of release of various gases. The accumulated organic solid wastes draw diseases causing vectors such as insects, pests and rodents. The diseases such as typhoid cholera are spread by such vectors. If the waste is not disposed properly, it can enter water bodies and cause contamination, block the drainage system, promote growth of mosquitoes and thus threaten human health.

(ii) Effects on the environment

The improper handling and management of waste very badly affects the physical environment. The contaminants of solid waste pollute water bodies, soil and air. The open burning of solid wastes lead to air pollution, which cause health problems and also subsequently distresses the sustainability of the environment.

(iii) Effects on aesthetic aspect of the Area

Solid waste if not disposed properly, affects the physical appearance of the locality. Littering of waste on streets spoils the scenic beauty of not only forest reserves and waster body but also the environment as whole.

(iv) Effects on Economic Growth

Cleaner cities are better able to invite tourists and private investments which help in creating more job opportunities and it can provide satisfactory services to its citizens. Thus proper solid waste management through improved waste collection facilitates can overcome all above effects.

Street cleaning

In addition to the waste generated on the premises, waste is also generated along the road sides and streets. The waste presents in streets are as follows:

1. Natural waste-waste blown from adjoining open spaces
2. Behavioural waste – waste deposited by pedestrians and people using the streets. Besides, waste from residences is often thrown by road sides
3. Wastes generated on road such as accidental spillage from loaded vehicles, construction wastes, animal droppings, oil spillage from vehicles and rubber during traffic congestion.
4.   The wastes generated from nearby residential, commercial and industrial areas
5. Wastes generated by the roadside vegetable and fruit vendors, street hawkers and slum dwellers.

Sweepers generally clean only major streets and drainage and avoid narrow street lanes. The sweepers usually don’t stop at each and every door step to collect waste but as per state Municipal act, they ought to collect household waste from each and every doorstep while sweeping the streets on daily basis. The sweeping is carried out manually by using short handled brooms, although there is a perceptible trend towards use of long handled brooms. Only major roads are swept every day according to the Municipal rules, the sweepers must and minor roads are swept once in a week. The manual cleaning work is usually carried out commonly (i.e.) one person sweeping the road and another will collect the waste materials in a hand cart. The work in two shifts from 6 to 12 AM in the first shift and 3 to 5 PM in the second shift. They work on six days a week but it is desirable that the work be carried out daily and holidays to different workers are staggered. The lack of manpower and insufficient available fund prove to be inefficient in dealing with this aspect properly.

Traditional Waste disposal: In the twentieth century, humans have dealt with solid wastes in three basic ways:

(1)   by burning the waste – Burning the waste results in generation of ash and release of gas and smoke to the environment

(2)   by storing wastes, including the leftover as from burning, in dumps, impoundments, and most recently sanitary landfills; and

(3)   by injecting or burying wastes in rock cavities deep underground – a method proposed for the disposal of industrial and conventional toxic or hazardous waste.

The following methods are used generally for disposal of solid waste

Open burning of Wastes

Incineration of waste at lower temperature in an uncontrolled manner is said to open burning. Although it is a traditional method of waste management, practiced by major population of the country, is not proper method of waste management. It reduces the quantity of waste. Around 40% of the worldwide solid waste is eliminated by open burning. In developing countries, it is widely practiced because it is an easy, cheap and effective way to get rid of solid waste. Generally open burring is carried out near the dumping site as it reduces the cost of transportation. Burning of solid waste leads to air pollution which in turn helps in heating up of earth drastically. It has been scientifically proved that open burning releases harmful gases and causes soil and water pollution.

Dumping of solid waste

Dumping of solid waste is one of the most common tradition methods of waste disposal. The waste is first cleared from the source of generation and dumped in specified location in such a way that it does not cause any serious implication to the humans and the environment. Nowadays urban local bodies have approved the dumping of waste as means of waste disposal. It is the responsibility of local association to ensure that the waste is safely disposed within its jurisdiction. In present scenario, there is no systematic or scientifically organised method for the treatment of waste, as a result of this there is build up of unhygienic condition around the dumping site. The mismanaged dumping sites pose serious threat to the environment and public health.

Waste dumping practice in major cities of India

Bengaluru: The waste is commonly dumped openly in the landfill site. This city consists of nearly fourteen open dumping sites where the wastes are piled in heaps without any treatment. It has 2 composting plants with the capacity of 220.4 tons and 330.6 tons of waste respectively but only one third of their waste handling capacity is only processed.

Kolkata:The waste is disposed by open dumping as well as closed landfillings. It has around 40 open dumping disposal sites and few landfill sites owned by private firm. Around 10 metric tons to 500 metric tons of solid waste are dumped in these sites per day.

Other parts of India practice more or less similar pattern of waste disposal method.

Table 1: Prominent dumping sites (open dumping) in major cities in India

Dumping of solid wastes into the Sea

Dumping solid waste into the sea is an age old practice because it is easy way to get rid of wastes. It is widely practised in the coastal areas throughout the world. The waste is generally taken in the canal boat and dumped at least 15 to 30 km from the coastline. This practise of waste disposal is however expensive and Not environment friendly.

1.  Merits

• Dumping of solid waste into the sea pose less hazard than landfill disposal and incineration of solid waste.
• Coastal fisheries and communities residing beside coastline may be minimally affected due to waste dumping in the deep ocean.
• The assimilative capacity of ocean is incredibly high as oceans are huge.
• With properly organized and well-designed dumping method, waste can be collected, concentrated and disposed in deep particular confined area in the ocean, which can cause least damage to the overall marine life.
• The waste dumped in ocean can be easily degraded due to abundant aeration and vast flora and fauna.
• It is one of the cheapest methods of waste disposal for the communities residing in the coastal areas.

2.  Demerits

It is economical to dump waste near the shore by the communities but transporting and disposing waste deep in the ocean requires huge investment and well-designed system.

The waste accumulated deep inside the ocean may have hidden risk in long run. In one of the investigations, the mercury level in the whale was found to be much higher than in the ocean, which may be due to bioaccumulation.

Once the toxins are dumped in ocean, the containment is not ensured, while in case of landfill disposal, consequences can be brought under control easily.

If the waste dumped contains more organic matter than it will result in the depletion of oxygen level.

Once, a damage is done to a particular area in the ocean, it will take long time to restore as the residence time of ocean is quite high.

Regulations for ocean dumping

Waste disposal without any proper planning have severely affected oceanic life. Around 200 red tides have been experienced yearly in Japan’s inland sea. In 1988, New York and New Jersey closed its beaches because of washing of medical wastes and sewage. Waste dumping has severely affected fishery industry as toxins get accumulated in the marine animals over a period of time and make them unsuitable for consumption. In 1890, Rivers and Harbors Act restricted disposal of waste into the U.S. navigable waters. In 1978, Hughes Amendment to Ocean Dumping Ban Act prohibited sewage dumping sludge. Pew Oceans Commission in 2003 declared set of rules for protecting the health of marine system. It mainly focused on prioratizing the ocean restoration and increasing economic return. It has doubled the investment on marine research and recommended creating a robust system of protected marine reserves.

Table 2: Acts and amendments related to ocean dumping

(codified as 33 U.S.C. 1401-1445, 16 U.S.C. 1431-1447f, 33 U.S.C. 2801-2805)

Disposal by tilling into the fields

The waste is generally buried into the farmer’s field and they are allowed to plough after some time. This practice is not much common and also not environment friendly.

Solid waste management in India

Methods such as incineration and pyrolysis are generally not practiced in India because the nature of solid waste (high moisture and high content of non combustible substances) in India is not suitable for such processes. Hence number of methods have been adopted and are consistently practiced for waste management. Some of the methods are developed for profit making. For example, the waste is sieved to separate larger particles and substances and further sand particles are also removed. Thereafter the finer constituents are palatalized and dried with the help of rotary hot air dryer. In order to convert waste constituents into pellets, binders such as lignin from vegetable waste are sometimes used. The heating value of the pellets is enough (~4000 kcal/kg waste) to be used as household fuel because of high content of biomass. The advantage of these pellets is that it burns without emitting any smoke unlike fuel wood and charcoal. Moreover, higher level of heat of combustion gives adequate result with small quantities. This method serves dual purpose of waste elimination and turning waste into useful fuel which is clean. These pellets are can efficiently replace charcoal.

Summary

In this lecture we educated about:

• Traditional waste collection methods
• old traditional disposal methods like open burning, disposal in water bodies and open dumping
• Open dumps of various cities
• acts regulating waste disposal in water bodies

References:

1. Frank Kreith, George Tchobanoglous, Handbook of Solid Waste Management, McGraw-Hill, 1994
2. Ramesha Chandrappa , Jeff Brown, Solid Waste Management: Principles and Practice (Environmental Science and Engineering) Springer; 2012
3. K.Sasikumar, Sanoop Gopi Krishna, Solid Waste Management, Prentice Hall India Learning Private Limited (2009).
4. M.S. Bhatt, Asheref Illiyan, Solid Waste Management: An Indian Perspective, Synergy Books India.
5. N.N. Bandela , D.G. Tare, Municipal Solid Waste Management, BR Publishing Corporation (2009)