Environment Engineering I

1. AnNajah National University Civil Engineering Department Environment Engineering I Solid Waste Management Dr. Amal Hudhud

2. perspective Solid waste describe things we through away According to USA EPA Solid Waste : include any discarded item thing destined for reuse, recycle or reclamation, sludge, hazardous waste exclude radioactive waste This chapter concern with Solid Waste generated from residential and commercial sources

3. Characteristic of solid waste • The term Refuse or Solid Waste is classified according to : • Point of origin (domestic, agriculture, industrial • Natural of material (organic, inorganic, putrescible …. • The classification of SW is used for choosing the treatment, collection, recycling and disposal options • Putrescible : animal and vegetable waste resulting from handling, cooking, preparing, and serving of food

5. Solid waste collection • Who make the collection? • City employees • Private firms (contract with city government- private residents) • Frequency of collection • Amount of waste • Climate • Cost • Public request

6. recycling 2- Method of collecting recyclable Materials • curbside collections ( one bins or number of bins) • Drop off centers

7. recycling 4-improving the Market for recyclables: factors effect market and price • Economic condition • Overall demand • Transportation cost • Quality of recovered material • Export market

8. composting • Compost : decomposition of organic materials such as leaves, grass and food by microorganism) crumbly, earthy smell, soil like material). Material to be composted should contain both Nitrogen and carbon sources (N:C, 1:30 to achieve optimum microorganism growth ) • The composting process involves four main components : organic matter, moisture, oxygen, and bacteria

9. Source reduction • prevent formation of waste. • Design manufacture, purchase and use material in way that minimize the amount of toxicity of the waste we generate. • Reduce waste – reduce cost of recycling, landfill, composting • Conserve natural resources, reduce pollution

10. Waste reduction and Process Modification: • Redesigning of product and packing to reduce the quantity of materials generated (reduction of mass) • Nontoxic material can be substituted for other toxic ones • Using Email

11. Reuse of product • Reusing when possible:- examples • Using durable coffee mugs rather than disposal cups • Reusing boxes for other purposes • Purchase refillable pens • etc

12. Education and legislation • Should education of people about benefits of recycling and reusing products and minimizing the waste or enforcing by legislation

13. Method of Disposal

14. Combustion (1) To reduce waste volume, local governments or private operators can implement a controlled burning process called combustion or incineration Burning waste at extremely high temperatures also destroys chemical compounds and disease-causing bacteria.

15. sanitary landfill (2) Land disposal site employing an engineered method of disposing of SW on a land in a manner that minimizing environmental hazards by spreading solid waste to the smallest practical volume, applying and compacting cover material at the end of each day

16. sanitary landfill Site selection Restricted location such as wetland flood plain, seismic impact areas Public opposition Proximity to roadways and bridge Location of GW table Soil condition and topography Availability of cover material

17. Sanitary landfill Operation Area method the most common method in operation SLF it uses three step: spreading the waste, compacting and covering with soil The waste is spread in 0.4 -0.6 m layer and compacted

18. Sanitary landfill Leachate Liquid that passes through the landfill, extract dissolved and suspended matter from waste material Liquid contains: decomposition of waste, rainfall, surface drainage and Groundwater

19. Sanitary landfill

20. Sanitary landfill When the landfill reach its field capacity (the quantity of water held against gravity)leachate begin to flow Amount of leachate is determined by Darcy law

22. Sanitary landfill Control of leachate: landfill must be lined in a specific manner to meet maximum contaminate level for G.W Specific liner include synthetics membrane 0.76 mm thick (HDPE, PVC….)

23. Sanitary landfill

24. Sanitary landfill Leachate treatment New landfill high concentration of Ammonia, organic chemical Old landfill high concentration of salts Treatment options: 1) directly to WWTP 2) pretreatment on site (flocculation- sedimentation –filtration) 3) treatment on site Activated sludge and Reverse Osmosis (RO)

25. Sanitary landfill Methane and other gases production: Emitted from a landfill as a result of microbial decomposition (CO2 and CH4)

26. Sanitary landfill Landfill Design Site Preparation, building, monitoring wells, size, liners, leachate collection system, final cover, gas collection. Where = volume of landfill (in m3) P = population E = ratio of cover (soil) to compacted fill = = volume of solid waste ( in m3) = volume of cover ( in m3) C = average mass of solid waste collected per capita ( in Kg. person -1) Dc= density of compacted fill (in Kg. m-3)

28. Sanitary landfill Landfill closure Final cover to be applied in order to prevent moisture from entering the closed landfill