- PDF Free Download

Size: px

Start display at page:

Download ""

Samuel Ward
5 years ago
Views:

1 UNIT -V DISPOSAL PART A (2 MARKS) 1.What is called municipal solid waste landfill (MFWLF)? Definition: depositing waste on the ground and burying it with at least six inches of dirt. Municipal solid waste landfill (MFWLF) receives household wastes but can also receive non-hazardous sludge, industrial solid waste, construction and demolition debris. 2.Define LEACHATE. LEACHATE = a liquid that has passed through or emerged from solid waste and contains soluble, suspended, or miscible materials removed from such waste. 3.What are the Landfill types? a) bioreactor landfills (bioreactors) air to enhance microbial processes b) construction and demolition debris (C & D) landfills shingles, metals, and some types of plastics standards than municipal solid waste landfills due to the relatively inert nature of C&D debris materials. c) industrial waste landfills -hazardous industrial process wastes. 4.What are the Advantages of landfills? Advantages of landfills: a) no burning needed b) air pollution minimal c) constant burying of the layers vermin (rats, etc.) are kept to a minimum 5.What type of Problems with landfills in disposal. Landfills require space Produce methane gas (can be used for energy, or can cause climate change) Leachate must be collected and treated Potential for water pollution NOT a long-term remedy. 6.What is called Secure landfills. Landfilling of hazardous solid or containerized waste is regulated more stringently than landfilling of municipal solid waste. Hazardous wastes must be deposited in so called EN6501-MUNICIPAL SOLID WASTE MANAGEMENT Page 1

2 secure landfills, which provide at least 3 metres (10 feet) of separation between the bottom of the landfill and the underlying bedrock or groundwater table. 7.Write about leachate collection system. A secure hazardous-waste landfill must have two impermeable liners and leachate collection systems. The double leachate collection system consists of a network of perforated pipes placed above each liner. The upper system prevents the accumulation of leachate trapped in the fill, and the lower serves as a backup. Collected leachate is pumped to a treatment plant. In order to reduce the amount of leachate in the fill and minimize the potential for environmental damage, an impermeable cap or cover is placed over a finished landfill. 8.What is meant by Leachate recirculation? Leachate recirculation: It is one of the simplest forms of treatment. Recirculation of leachate reduces the hazardous nature of leachate and helps wet the waste, increasing its potential for biological degradation. 9.What is meant by Natural liners? Natural liners: These refer to compacted clay or shale, bitumen or soil sealants, etc., and are generally less permeable, resistant to chemical attack and have good sorption properties. They generally do not act as true containment barriers, because sometimes leachate migrates through them. 10. What is meant by Synthetic (geo-membrane) liners? Synthetic (geo-membrane) liners: These are typically made up of high or medium density polyethylene and are generally less permeable, easy to install, relatively strong and have good deformation characteristics. They sometimes expand or shrink according to temperature and age. 11.What are the minimum requirements you need to consider for a sanitary landfill? The four minimum requirements you need to consider for a sanitary landfill are: (i) (ii) (iii) (iv) full or partial hydrological isolation; formal engineering preparation; permanent control; planned waste emplacement and covering. 12. What is meant by sanitary landfill? Sanitary landfill means amethod of disposing of solid waste or on land without creating nuisances or hazards to public health or to the environment by utilizing the principles of engineering to confine the solid waste to the smallest practical area, to reduce it to the smallest practical volume, and to cover it with a layer of an approved material. EN6501-MUNICIPAL SOLID WASTE MANAGEMENT Page 2

3 13. What is meant by fill area? Fill area means the area containing waste placed for final disposal not including earthen beams or other facility appurtenances. 14. Mention the types of landfilling methods? Area method Trench method Depression method 15. what are the gases found in landfills? Ammonia Carbon dioxide Carbon monoxide Hydrogen Hydrogen sulphide Methane Nitrogen Oxygen 16. Mention the methods to control seepage. The use of impermeable cover materials The interception of high groundwater before it reaches the fill. Equalization of the water levels within and outside the landfill. The use of an impervious layer of clay material or other materials. 17. What are the equipments used for sanitary landfills? Crawler and rubber-tired tractors Scrapers Compactors Draglines Motor graders 18. What are the factors to be considered for effective site selection for disposal of solid wastes? Available land area Impact of processing and resource recovery Haul distance Soil conditions Topography Climate EN6501-MUNICIPAL SOLID WASTE MANAGEMENT Page 3

4 Surface and sub-surface water conditions Geologic and local environmental conditions 19. Define sludge. Sludge means any solid, semi-solid, or liquid waste generated from a municipal, commercial, industrial waste water treatment plant, water supply treatment plant, or air pollution control facility, exclusive of the treated effluent from a wastewater treatment plant. 20.what is meant by pyrolysis? Pyrolysis is a thermochemical decomposition of organic material at elevated temperatures in the absence of oxygen. It involves the simultaneous change of chemical composition and physical phase, and is irreversible. The word is coined from the greek derived elements pyro fire and lysis separating EN6501-MUNICIPAL SOLID WASTE MANAGEMENT Page 4

5 UNIT -V DISPOSAL PART B (16 MARKS) 1. Explain the various phases of MSW decomposition in a closed landfill cell. How do leachate and gases differ b/w each phase? What are the factors which affect production of leachate & landfill gas? 2. What are the issues should be considered before deciding on gas ventilation from a landfill? Explain a typical gas vents used in the surface of a landfill for the control of landfill gas. 3. Explain the various phases of MSW decomposition in a closed landfill cell. 4. Identify the adverse effects of a landfill leachate and list appropriate control measures. 5. Explain the various methods of leachate treatment. 6. Explain in detail the important aspects in the implementation of sanitary landfill. 7. i) What are the environmental factors in sanitary landfill sites? ii) Discuss the different methods used for MSW landfill. 8. With the help of a neat sketch, compare the cross section of liner systems, and cover systems recommended for sanitary landfill. 9. i) Explain the step by step procedure involved in site selection for sanitary landfills ii) With the help of a neat sketch explain the essential components of a sanitary landfill and their functions. Also explain its advantages and disadvantages of sanitary landfill. 10. i) Enlist the key characteristics of an engineered landfill that distinguishes it from an opendump. ii) With the help of a neat sketch describe the operational components of a landfill and state their functions. 11. i) Elaborate the post closure care required for a secure landfill ii) List out the factors that must be considered in identification of potential site for a secure landfill. Describe site selection procedure. 12. Explain briefly about the various characteristics of hazardous wastes. EN6501-MUNICIPAL SOLID WASTE MANAGEMENT Page 5

BIOREACTOR LANDFILLS: AN INNOVATIVE TECHNOLOGY FOR SUSTAINABLE MANAGEMENT OF SOLID WASTE. Rao Y. Surampalli

BIOREACTOR LANDFILLS: AN INNOVATIVE TECHNOLOGY FOR SUSTAINABLE MANAGEMENT OF SOLID WASTE Rao Y. Surampalli Bioreactor Landfills Municipal solid waste landfills that utilize bulk liquids in an effort to