Disposal of waste

Waste production is one of the major human activities affecting environmental quality.

1. DISPOSAL OF WASTE AB.RAJAR. ASSOCIATE PROFESSOR. COMMUNITY HEALTH SCIENCES. MUHAMMAD MEDICAL COLLEGE.

2. LEARNING OBJECTIVES. Introduction. Types of waste (refuse). Sources of waste (refuse) Methods of collection and disposable of waste (refuse). Public health importance of waste (refuse).

3. INTRODUCTION Waste production is one of the major human activities affecting environmental quality. The exploitation of natural resources is driven by a society’s need for socio-economic development within the global market & basic individual level requirements to maintain a standard of living. These driving forces have increased the tendency of waste produced or the effects of this exploitation of resources. Therefore actions that contribute to waste production are attributable to both poor & rich alike & are threat to quality of life for future generations .

4. INTRODUCTION(cont..) The production of waste is a consequence of human activity, waste is produced as a result of: “-Mining, -Energy production, -Manufacturing, -Domestic activities.” The waste is produced in a number of forms like,air,solid or liquid, any of which may be hazardous. Each type of waste needs to be dealt with in the best practicable way in order to minimize the effects on the environment & on the health.

5. SOLID WASTE The term “solid wastes", includes: Garbage (food wastes) Rubbish ( paper,plastics,wood,metal,throw-away containers, glass), Demolition products ( bricks,masonry,pipes), Sewage treatment residue (sludge& solids from the coarse screening of domestic sewage) And Dead animals, manure and other discarded material.

6. TYPES OF WASTE Non Hazardous waste: Refuse, garbage, sludge, municipal trash. Hazardous waste: Solvents acid, heavy metals, pesticides, and chemical sludge Radioactive Waste: High and low-level radioactive waste Mixed waste: Radioactive organic liquids, radio active heavy metals. ” ( Moeller, 2005).

7. TERMANOLOGY WASTE/REFUSE : The term is applied to unwanted or discarded waste material from houses,street,sweeping,commercial,industrial & agricultural operations, arising from man’s activities. RUBBISH: It comprises paper,clothing,bits of wood,metal,glass,dust & dirt etc. GARBAGE: The waste mater arising from the preparation, cooking & consumption of food, consisting of waste food, vegetable peelings & other organic matter.

8. TERMANOLOGY(cont…) SEWAGE : Waste water consisting of liquid & solid human excreta together with liquid from cow shed stables,houses,factories etc,carried out in a sewer. SULLAGE: Waste water from houses unmixed with solid excreta as from kitchen , pantry & bath rooms. SLUDGE: Solid component of sewage left at the bottom of a septic tank. SANITATION: The means of collecting & disposing of excreta & community liquid waste in a hygienic way so as not to endanger the health of individuals & the community as a whole.

9. SOURCES Domestic refuse : Ash,Rubbish,Garbage etc. Street refuse: Leaves,straw,paper,animal droppings etc. Market refuse : Vegetable & animal matters etc. Clinical refuse Industrial/Trade/Commercial refuse. Agricultural refuse.

10. METHODS OF DISPOSAL OF SOLID WASTE

11. METHODS OF DISPOSAL OF SOLID WASTE INSANITARY METHODS 1. Hog feeding 2 . Dumping SANITARY METHODS 1. Sanitary landfill/ Controlled tipping 2. Composting 3. Incineration 4. Manure pits 5. Burial 6. Biogas plant

12. METHODS OF DISPOSAL OF SOLID WASTE In PAKISTAN the principal methods of solid waste disposable are: DUMPING & FILLING : COMPOSITING : Controlled tipping (or) sanitary landfill : INCINERATION : MANURE PITS: BURIAL : DESRUCTORS :

13. METHODS OF DISPOSAL OF SOLID WASTE This practice varies from country to country , depending on many factors, including the resources available. Waste management varies b/w high & low income countries. The main difference is organization , for instance, there is a formalized process of collection of waste in low & middle income countries. Another difference is the use of resource technology .

14. INSANITARY METHODS 1. HOG FEEDING : The garbage is fed to animals, carful supervision is necessary. Disadvantages: Can spread many diseases to man, when uncooked garbage is fed to hogs, such as trichinosis, hog cholera, food and mouth diseases.

15. INSANITARY METHODS 2. DUMPING – Refuse dumped in low lying areas – Bacterial action over time, decreases volume of refuse which is gradually converted into humus D isadvantages: Smell Unsightly appearance Free access to flies, rodents, hogs, dogs etc. Dispersal by wind Pollution of surface and ground water

16. METHODS OF DISPOSAL OF SOLID WASTE(cont..) 2.DUMPING & FILLING : Refuse is dumped in low lying areas partly as a method of reclamation of land but mainly as an easy method of disposal of dry refuse Advantage : It will fill up the depressions. Disadvantages: Refuse is exposed to flies & rodents. Sources of nuisance from the smell & unsightly appearance. The loose refuse is dispersed by wind. WHO Committee considered dumping as a “a most insanitary Method of disposal that creates public health hazards, a nuisance & sever pollution of the environment". So dumping should be outlawed & replaced by sound procedures.

17. METHODS OF DISPOSAL OF SOLID WASTE(cont..) 3) CONTROLLED TIPPING (OR) SANITARY LANDFILL : It is the most satisfactory method of refuse disposal where Suitable land is available. Three methods are used: The trench method. The ramp method. The area method.

18. Controlled tipping (or) sanitary landfill : Trench method – Level ground – Trenches 4-12 m wide, 2-3 m deep – Refuse is compacted and then covered with excavated earth. Ramp method – Sloping terrain. Area method – Land depressions, disused quarries, pits – May need soil from outside sources to cover the compacted refuse

19. 4 .COMPOSITING : Compositing is a method of combined disposal of refuse & night soil or sludge . It is a natural process in which organic matter breaks down-results in the formation of Humus like material called as Compost a high manurial value for the Soil. METHODS OF DISPOSAL OF SOLID WASTE(cont..)

20. 5 .INCINERATION: Refuse can be disposed off hygienically by burning or incineration. Hospital refuse which is dangerous should be disposed off by incineration. ADVANTAGES: Suitable for areas where land is not available for sanitary landfill Example : Hospitals. DISADVANTAGES: Expensive No useful by-product Air pollution METHODS OF DISPOSAL OF SOLID WASTE(cont..)

21. METHODS OF DISPOSAL OF SOLID WASTE(cont..) 6 .MANURE PITS : In rural areas there is no system for collection & disposal of refuse. The garbage, cattle dung, straw & leaves should be dumped into the manure Pits & covered with earth after each day’s dumping.

22. 6.BURIAL: This method is suitable for small camps. A trench is excavated & the refuse is dumped in it. METHODS OF DISPOSAL OF SOLID WASTE(cont..)

23. 7.DESRUCTORS : The town refuse is destroyed in a destructor & the residual Clinker is crushed & manufactured into: Paving slabs, B ricks, Mortar O ther saleable products. METHODS OF DISPOSAL OF SOLID WASTE(cont..)

24. 8.DILUTION : Refuse is also disposed of by diluting in the river or sea water. Improper disposal may be harmful to aquatic life & to humans when they use the water or consume fish . METHODS OF DISPOSAL OF SOLID WASTE(cont..)

25. WASTE WATER DISPOSAL OUT IN THE STREETS OR PONDS

26. METHODS OF EXCRETA DISPOSAL A.UNSEWERED AREAS: 1.SERVICE TYPE(Conservancy system ). 2.NON-SERVICE TYPE(Sanitary latrines 3.LATRINES FOR TEMPORARY USE/CAMS.

27. A.UNSEWERED AREAS: 1.SERVICE TYPE(Conservancy system). Night soil is collected from pail or bucket type Of latrines by human agency,& later disposed of . METHODS OF EXCRETA DISPOSAL

28. A.UNSEWERED AREAS: 2.NON-SERVICE TYPE(Sanitary latrines a)Bore-hole latrine. b)Dug well or pit latrines. c)Water-seal type of latrines. d)Septic tank . METHODS OF EXCRETA DISPOSAL

29. A.UNSEWERED AREAS: 3.LATRINES FOR TEMPORARY USE/CAMS. a)Shallow Trench latrines. b)Deep Trench latrines. c)Pit latrine. d)Chemical closet. METHODS OF EXCRETA DISPOSAL

30. METHODS OF EXCRETA DISPOSAL(cont..) B.SEWERED AREAS: 1.Water-carriage system. This system implies collecting & transporting of human excreta & waste water from residential, commercial & industrial areas by a network of underground pipes called sewers to the place of ultimate disposal. Elements of Water Carriage System . Water closet, Cistern, Trap, Water-seal, Soil pipe, House drain, Sewer ,

31. WASTE MANAGEMENT “ SUSTAINABLE DEVELOPMENT is based on meeting the goals & needs of the present generations without compromising the needs of future generations.” There it is not appropriate simply to keep disposing off waste in various ways. Clear methods for waste management need to be in place,determinig how to reduce it or process it in the best practicable way.

32. TREATMENT OF WASTE/SEWAGE WASTE MANAG EMENT : This is defined as any method , technique or process that Is designed to change the physical , chemical or biological character or composition of a ( hazardous) waste . Ideally this will act to neutralize it, recover unexploited energy, render it less hazardous or make it safer to transport, store or dispose off. OBJECTIVES : Its objective is to produce an environmentally-safe fluid waste stream(treated effluent) & a solid waste(treated sludge) suitable for disposal or reuse(fertilizer ).

33. Waste treatment and disposal WASTE TREATMENT Incineration Solidification Heat treatment: Chemical treatment WASTE DISPOSAL Landfills Underground injection wells Waste piles land treatment In less developed countries flowing rivers

34. TREATMENT OF WASTE/SEWAGE(cont..) TYPES: 1.Primary treatment: It consist of temporarily holding the sewage in a quiescent basin where heavy solids can settle to the bottom while oil, grease & lighter solids float to the surface . Screening , Removal of girt in girt chamber, Primary Sedimentation .

35. TREATMENT OF WASTE/SEWAGE(cont..) TYPES: 2.SECONDRAY TREATMENT: It removes dissolved & suspended biological matter. Artificial biological treatment, Secondary sedimentation, Digestion of sludge.

36. 3.Tertiary treatment; Treated water is disinfected chemically or physically prior to discharge into a stream,river,or wetland,etc or it can be used For the irrigation. TREATMENT OF WASTE/SEWAGE(cont..)

37. TREATMENT OF WASTE/SEWAGE(cont..) 4.Disinfection : Chlorination is required where effluents are to be discharged into waters used for shellfish growing, drinking or bathing.

38. The waste water being utilized for irrigation

39. WASTE HEIRARCHY By waste hierarchy we mean that “Priority is placed on the Re-use & recycling of waste rather than its disposal”. The waste hierarchy ensures an integrated approach to waste Management policy or decision making. Each decision is based On the most environmentally sound way to deal with waste. - Reduce, -Re-use, -Recycle, -Energy recovery, -Disposal.

40. WASTE HEIRARCHY

41. WASTE HEIRARCHY (cont…) RECYCLING IS OF TWO TYPES . 1.Primary or closed loop recycling : In this post consumer materials such as glass, paper, metals, & plastics are collected & recycled to create new products of the same type, like newspaper into newspaper, plastic into plastic can. This method can reduce the use of virgin materials in the product by 20-90%. 2 ) Secondary or open loop recycling :- It reduces the use of virgin material by 25%. In this system the waste material is converted into different products, for e.g., polypropylene ice-cream containers are re-manufactured as clothes pegs or rubbish bins.

42. DEALING WITH MATERIALS USE AND WASTES 1st Priority 2nd Priority Last Priority Primary Pollution and Waste Prevention • Change industrial process to eliminate use of harmful chemicals • Purchase different products • Use less of a harmful product • Reduce packaging and materials in products • Make products that last longer and are recyclable, reusable or easy to repair Secondary Pollution and Waste Prevention • Reduce products • Repair products • Recycle • Compost • Buy reusable and recyclable products Waste Management • Treat waste to reduce toxicity • Incinerate waste • Bury waste in landfill • Release waste into environment for dispersal or dilution

43. PUBLIC HEALTH IMPORTANCE : Human excreta are a source of infection & are an important cause of environmental pollution. Every society has responsibility for its safe removal & disposal so that it does not constitute a threat to public health . THE HEALTH HAZARDS OF IMPROPER EXCRETA DISPOSAL ARE: Soil pollution, Water pollution, Contamination of food, Propagation of flies. Proper disposal of human excreta is a fundamental environmental Health service without which there can not be any improvement in the of community health. EXCRETA DISPOSAL

44. WASTE PREVENTION/MINIMIZATION If we do not allow waste to accumulate ,then it becomes a very hazardous environmental & health problem b/c: Waste decomposes & favors fly breeding. It attracts rodents, vermin (bugs, lice, fleas) The pathogens which may be present in the solid waste may be conveyed back in man’s food through flies & dust. There is possibility of water & soil pollution. Heaps of refuse present & poor appearance & nuisance from bad odor The overall atmosphere & ecosystem may be disturbed which might affect the health of the individual.

45. WASTE PREVENTION/MINIMIZATION(cont…) There is a co-relation b/w improper disposal of solid wastes & incidence of vector-born diseases. Therefore in all civilized countries , there is an efficient system for its periodic collection, removal & final disposal without risk to health. Waste prevention aims to reduce the amount of waste generated in the first place. By reducing or removing the presence of hazardous substances in waste materials, it also leads to a simplification of disposal practices .

46. EFFECTS OF SOLID WASTE ON ANIMALS AND AQUATICS LIFE Increase in mercury level in fish due to disposal of mercury in the rivers. Plastic found in oceans ingested by birds Resulted in high algal population in rivers and sea. Degrades water and soil quality

47. Impacts of solid waste on Environment. Waste breaks down in landfills to form methane, a potent greenhouse gas Change in climate and destruction of ozone layer due to waste biodegradable Littering ,(litter=a vehicle with caution carried by men or bearers) due to waste pollutions, illegal dumping. Leaching: is a process by which solid waste enter soil and ground water and contaminating them.

48. THANK YOU, AND LETS STRIVE TOGETHER TO KEEP OUR CHILDREN SMILING