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15 Cards in this Set
- Front
- Back
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what is the definition of composting?
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biological decomposition and stablization of organic substrates, which allow thermophillic temps to produce the final product
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what is the final product of composting?
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final product is stable, free of pathogens, and plant seeds
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what are the ingredients of composting?
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unstable OM
air water |
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what are the products of composting?
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stable OM
heat gases microbial biomass |
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what are the benefits of composting?
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low risk
improves soil fertility cost competitive |
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what are the 3 phases in composting?
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Mesophillic phase
Thermophillic phase Curing or stabilization phase |
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explain the mesophillic phase.
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about 20-40 degrees C
microbes degrade Carbon respiration heats compost to thermophllic range |
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explain the thermophillic phase
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40-80 degrees C
most rapid decomposition up to 60 degrees sanitizes aids metabolism of xenobiotic |
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explain the curing or stablization phase
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slow cooling
eliminates odors eliminates seed germination problems |
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what are the physical and chemical changes which occur during the composting process?
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C/n ratio decreases steadily
Mineral N (nh4 and no3) decline to near zero ph and ash % increase |
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what is the best c/n ratio for compostable wastes?
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25-35 c/n ratio
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what is a good moisture content for compostable wastes?
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40-60%
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what are two bulking agents?
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wood chips, shredded tires
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what are the three batch systems of composting?
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static pile, windrow, aerated static pile
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what is an example of an aerated static pile?
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Beltsville system
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