Reading guidance：Traditional sludge disposal methods and new sludge disposal methods hold different advantages. Relevant analysis is presented as following: Traditional resource of sludge disposal technology is mature,

     Traditional sludge disposal methods and new sludge disposal methods hold different advantages. Relevant analysis is presented as following:
    Traditional resource of sludge disposal technology is mature, technology risk is small, but has the resources product added value is low, environmental pollution is serious, investment, covers an area of and other disadvantages. Incineration of sludge rapidly maximum reduction, is currently China's most widely used sludge resource disposal technology. But incineration process will produce a large number of flue gas, the main component of CO2, N2, O2, H2O, and also contain some harmful substances: acid gases (HCl, HF and SO2, NOx, Co, carbon hydrogen compounds and heavy metal (Pb, Hg and dioxin PCDDs / PCDFs). At present our country incineration equipment mostly purchase from abroad, investment is large, the cost of investment is 30 ~ 40 million yuan / T processing capacity, operation cost is 350 to 500 yuan / T, direct revenue generation is about 40 yuan / tds. currently rely mainly on government support operation, should strengthen the incineration power generation equipment R & D and production, reduce the cost of equipment, and improve the amount of sludge generation, control of environmental pollution and improve the rate of resource. Composting technology is sludge disposal technology for China's national conditions and characteristics in most areas, the aerobic composting of the investment cost of 20 ~ 500 thousand yuan / T processing capacity, the operation cost is 100 to 150 yuan / T, relative to other resource processing way of low cost, but it occupies large processing cycle long (over 1 months), there is odor pollution to the environment, to be used in the big city. At the same time, heavy metals in sludge, organic pollutants degradation cannot limit its application, should strengthen the control of heavy metals, organic pollutants, ensuring the safe use of sludge compost. After composting for ecological restoration, forest land, garden or the manufacture of organic fertilizer for different purposes, income between 40 to 400 yuan / TDS range. Sludge in cement is mainly used to the sludge and cement kiln co processing, due to the cement kiln is readily available, the investment cost is low, higher operation cost is about 290 yuan / TDS, direct income about 20 yuan / tds. sludge anaerobic digestion bio gas operation cost at around 200 yuan / T, greatly reduce the sludge volume, while eliminating sludge odor, kill the sludge in the pathogenic bacteria and parasite eggs. But there is a large volume of equipment, processing cycle is long, covers an area of more than, investment cost disadvantages.
    Sludge disposal technology emerging generally has small area, fast processing speed, resource products with higher value-added features, but because the technology is not mature, technology risk. Sludge microbial protein extraction technology has the following characteristics. The low cost and equipment investment of about 200 thousand yuan / T, the operation cost is 100 ~ 150 yuan / t; the processing time is short, small area, single batch sludge processing time 4H; the process of safety and environmental protection, sludge storage, broken were carried out in a closed vessel, escaping gas pipeline through collecting and processing, no waste water and waste residue emissions; the resources of high value-added products, microbial protein has good foam-ability, foam stability, and high nutritional value, as the protein foam extinguishing agent, foam concrete foaming agent and nutritional agents with high added value. The sludge residue After hydrolysis of the wall safe, rich in nitrogen, phosphorus and potassium and pep-tides, nutrients, as greening soil, building filling material or processing into soil improvement agent and organic fertilizer are widely used. But, due to the short time of the technical application, security problems during the operation and product of the market need further research and practice. Sludge powder technology investment cost is higher, about 40 million yuan / T, operating costs about 200 yuan / tons short treatment time, about for 25 hours. The technology to a large number of absorptive sludge at the same time, the resources obtained by the product added value is high. But it is easy to produce odor treatment process and need to set deodorizing system. This technology can absorb a great amount of sludge, recycling products obtain high added value. But it is easy to produce odor in the process, need to set the deodorizing system. The sludge composting technology with subcritical hydrolysis treatment time is short (about 1H), covers an area of small, non pollution, resource product safety and high added value the characteristics, but with a slightly higher investment cost, the application time is short. The advantages of technology for oil sludge pyrolysis operating system is closed, volume reduction and high efficiency, no pollution emissions, and almost all the heavy metal particles remaining in the solid residue. More importantly, gas in the pyrolysis process at the same time can also be made of precious liquid fuel, to achieve energy self-sufficiency and resource recycling. But the technology has not been applied examples, the need to strengthen the experimental research.
 

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