Compost activators

The biodegradation of the reference material (cellulose) used to check the compost activity was evaluated in the same way. 

Filter Matrix The most common filter substrates in use today are soils or compost produced from leaves, bark, wood chips, activated sludge, paper, or other organic materials. In selecting a proper filter substrate for a specific use, the following should be considered ... 

For best results temperature should he maintained hetween 322 and 327 K (130 and 140°F) for the first few days and hetween 327 and 333 K (130 and 140°F) for the remainder of the active composting period. If temperature goes beyond 339 K (150°F), biological activity is reduced significantly... 

Initial carbon-nitrogen ratios (by mass) hetween 35 and 50 are optimum for aerobic composting. At lower ratios ammonia is given off Biological activity is also impeded at lower ratios. At higher ratios nitrogen maybe a limiting nutrient. 

Composting is the process of aerobic thermophilic decomposition of organic wastes to a relatively stable humus. Decomposition results from the biological activity of microorganisms which exist in the waste. 

Figure 3 Pectinase activity in 20 g of solid substrates composting of wheat bran, rice bran and rice husk (18 0 2) with the addition of 1 g raw starch from cassava tuber, 1 g pectin or 0.5 g yeast extract.

Composted dung is richer in nutrients and more active, provided it has been properly made, than comparatively fresh material that has not decomposed. However, in ordinary practice, manure cannot be rotted or stored without serious loss. Although well-rotted manure may contain more plant food than an equal weight of fresh manure, a given quantity of fresh manure will contain more plant food than composted manure that has been stored. 

An alternative arrangement, as illustrated in Figure 25.20, replaces the packing with soil or compost in a bio-filter. One advantage of the bio-filter is that the compost usually used for such systems contains a reservoir of nutrients to sustain biological growth, and additional nutrients do not normally need to be added. However, biological activity eventually starts to decrease, and the bed will need to be replaced after typically five years. 

In this study, waste was separated manually and composted without air pumping. Therefore, neither energy nor auxiliary fuels were needed. However, whenever RDF is produced in factory settlement, electricity and diesel are needed together with other supplement activities. For that system by using DSP method, separation, transportation, and other processes are required. Therefore, 93.8 kWh of electricity is needed for 1 ton of input waste operation [15]. 

Moreno J.L., Hernandez T., Garcia C. Effect of a cadmium-contaminated sewage sludge compost on dynamics of organic matter and microbial activity in an arid soil. Bio Ferti Soils 1999 28 230-237. 

Yamada Y, Kawase Y (2006) Aerobic composting of waste activated sludge kinetic analysis for microbiological reaction and oxygen consumption. Waste Manage 26 49-61... 

Amir S, Halidi M, Merlina G, Hamdi H, Jouraiphy A, Gharous ME, Revel JC (2005) Fate of phthalic acid esters during composting of both lagooning and activated sludges. Process Biochem 40 2183-2190... 

Mondini C, Famasier F, Sinicco T (2004) Enzymatic activity as a parameter for the characterization of the composting process. Soil Biol Biochem 36 1587-1594... 

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