Municipal sludge is a sewage treatment plant and sewage treatment process will produce pollutants accounted for 0.3% of the amount of sewage - 0.5%, is a viscous colloidal structure, a bacterial living cells formed by the bacteria micelles, extracellular polymer And water to form a solid-liquid mixture, turbid, solid suspended state. Difficult to dehydrate, exudes stench, water content of more than 80%. Therefore, after the sludge has not been properly treated into the environment, directly to the water and the atmosphere to bring secondary pollution, not only reduces the effective handling capacity of sewage treatment system, but also on the ecological environment and human activities constitute a serious threat. But the sludge contains a lot of plant nutrition, so the sludge is a renewable resource.
Food waste, commonly known as swamp feet, is the human life in the process of forming the life of waste, easily perishable, sporadic, spread of bacteria and viruses. The main ingredients of food waste include rice and flour food residues, vegetables, animal and vegetable oils, meat bones, etc., from the chemical composition, there are starch, cellulose, protein, fat and inorganic salts. The main features of the kitchen is rich in organic matter, but also contains nitrogen, phosphorus, potassium, calcium and various trace elements, high recycling value. But the moisture content is high, perishable, its traits and smell will have adverse effects on environmental sanitation, and easy to grow sick busy micro-organisms, mycotoxins and other harmful substances.
The characteristics of food waste: high water content (70% -90%) grease content (1% -5%), affecting peoples vision and smell, with waste and resources of the duality. As the composition of complex, which will increase the difficulty of treatment of oil and salt, decay speed, long processing time, so that the value of food waste recycling, but the impact on environmental pollution.
Domestic sewage is mainly used in urban life, a variety of detergents and sewage, garbage, feces, etc., mostly non-toxic inorganic salts, domestic sewage nitrogen, phosphorus, sulfur and more pathogenic bacteria. Domestic sewage is also a low-temperature heat source and methane source, it is far-sighted oil and gas fields. Domestic sewage contains a lot of organic matter, such as cellulose, starch, carbohydrates and fat protein; also often contains pathogens, viruses and parasite eggs; inorganic salts of chloride, sulfate, phosphate, bicarbonate and sodium, Potassium, calcium, magnesium and so on.