Lcrs In Environmental Engineering

5' to groundwater

10' to bedrock

LCRS = Leachate collection and removal system Composite = Synthetic liner + Low permeability soil

*Based on volume and the physical, chemical, and biological characteristics of the solid waste.

FIGURE 3.29 Industrial/commercial and ash monofill waste landfill liner configuration. (New York State, 6 NYCRR Part 360, Solid Waste Management Facilities, New York State Department of Environmental Conservation, Division of Solid Waste, Albany, 1990a.)

recirculation. Controlled leachate recirculation, including nutrient addition to maintain optimum moisture and pH, can enhance anaerobic microbial activity, breakdown organics as shown by reduced total organic carbon (TOC) and chemical oxygen demand (COD, convert solid waste organics to methane and carbon dioxide, and precipitate heavy metals. Complete biological stabilization can be achieved in four to five years. Heating of recirculated leachate to 86 °F (30 °C) has been found to accelerate the stabilization process.

A landfill designed for leachate recirculation should, as a minimum, incorporate a conservatively designed liner system and an effectively maintained leachate collection, removal, and recirculation distribution system, in addition to a gas collection and venting system (see Figure 3.30). A double-liner system with leak detection monitoring wells would enable the landfill owner and regulatory agency to monitor the liner system performance. The leachate collection and removal system should be designed to be accessible for routine maintenance and cleaning in view of the potential for biological film clogging. Recirculation would increase the strength of the recirculated leachate and accelerate fill stabilization. Establishment of early gradual recirculation and an active anaerobic biomass is important as each cell is closed. A final site closure utilizing a relatively impermeable crowned cap and surface-water drainage system should be implemented for final site closure.

Leachate Treatment Leachates containing a significant fraction of biologically refractory high-molecular-weight organic compounds (i.e., those in excess of 50,000) are best treated by physicochemical methods, such as lime addition followed by settling. Leachates containing primarily low-molecular-weight organic compounds are best treated by biological methods, such as activated sludge.

to treatment facility

FIGURE 3.30 Bioreactor type landfill with leachate recirculation: (a) schematic diagram and (b) photograph of a highly instrumented anaerobic landfill bioreactor located at Davis, California. Photo of bioreactor was taken shortly after landfill was completed, before significant decomposition had occurred. (Source: O'Leary, P. R., and G. Tchobanoglous, "Landfilling," in G. Tchobanoglous and F. Kreith (Eds.), Solid Waste Handbook, 2nd ed., McGraw-Hill, New York, 2002, Chapter 14.)

FIGURE 3.30 Bioreactor type landfill with leachate recirculation: (a) schematic diagram and (b) photograph of a highly instrumented anaerobic landfill bioreactor located at Davis, California. Photo of bioreactor was taken shortly after landfill was completed, before significant decomposition had occurred. (Source: O'Leary, P. R., and G. Tchobanoglous, "Landfilling," in G. Tchobanoglous and F. Kreith (Eds.), Solid Waste Handbook, 2nd ed., McGraw-Hill, New York, 2002, Chapter 14.)

Combinations of these methods may be required to achieve permit requirements and stream discharge standards. In the final analysis, the treatment required will depend on the composition of the fill material, leachate volume and characteristics, and the water pollution control standards to be met.

TABLE 3.22 Typical Constituents in Landfill Gas
Renewable Energy Eco Friendly

Renewable Energy Eco Friendly

Renewable energy is energy that is generated from sunlight, rain, tides, geothermal heat and wind. These sources are naturally and constantly replenished, which is why they are deemed as renewable.

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