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Task 3. Homework Sludge has been mechanically dewatered to 20% total solid content. From total solids, 75% is organic matter (VS) and 50% of organic matter is assumed to be biodegradable (BVS). It is assumed that composting process releases heat 23.3 MJ per one kilo of biodegradable matter. Sludge is composted and total solids content is set as 60 % for the final product. Calculate how much bulking agent is required per kilogram of sludge in order to reach 60% total solids content for ready compost. The amount of energy for water evaporation (Q) is assumed to be 70% of that amount of energy which is released when composting biodegradable matter. Sawdust is used as the bulking agent and its total solids content (TS %) is 65 %. Organic content of total solids (VS% of TS %) is 95 % and 20% of organic content is biodegradable (BVS). The composting of saw dust is assumed to generate heat 17.5 MJ/kg saw dust.