Reading guidance：In recent years, sludge problems have been paid attention to by all levels. Sludge disposal work has become a necessary work. Our government has established some relevant standards, technology and rele

     In recent years, sludge problems have been paid attention to by all levels. Sludge disposal work has become a necessary work. Our government has established some relevant standards, technology and relevant technical parameters for sludge disposal. Sludge treatment process consists of sludge thickening, dehydration, composting, digestion, landfill, incineration and other, in sludge treatment, several unit technology in common use, in order to achieve final good results, in order to meet the sludge reduction, harmless, resources of the basic principles. Sewage treatment smaller sewage treatment plant sludge treatment process is the sludge concentration, sludge dehydration of modulation, then the processed sludge transported to landfill landfill field; and has the large sewage treatment capacity of sewage treatment plant general construction of sludge digestion facilities, this kind can thoroughly treatment sludge, and can use energy - bio-gas can be obtained.
    In the year of 2012, we have achieved some successes: a: the national advanced incineration disposal technology of microorganism source reduction and dehydration of resources; b) pyrolysis sludge stabilization treatment technology; c) classification of anaerobic digestion technology; d) water earthworm in situ digestion technology. The above process a) and b) uses combined technology of sewage sludge, a) the technology is characterized by the use of special bacteria in water treatment, sludge reduction, after dehydration after drying and incineration of sludge reduction. More than 95%, no two pollution, suitable for municipal and industrial sludge treatment and disposal; b) in the technical characteristics of water heat treatment technology, will be difficult to take off the cell water into free water and after the gravity concentration and mechanical dehydration, water content decreased to 50%, the recovery of waste bio-gas anaerobic fermentation processing of dehydration. Sludge reduction rate is greater than 90%, suitable for city sewage treatment plant sludge; c) in technology adoption and kitchen Mixed waste anaerobic fermentation process, the recovery of bio-gas, 70% of the organic matter degradation. Applicable to municipal, industrial sludge and solid organic and integrated process of kitchen garbage and excrement; d) technology in the ecological food chain extension process, put water earthworm prey in the water sludge, achieve a reduction, reduction will reach 50% to 80%. It is suitable for urban sewage treatment.
    Other techniques for sludge treatment and disposal: a) high pressure diaphragm filter press dehydration sludge, this technique is a diaphragm type filter press, water content of sludge discharged is greatly reduced greatly; moisture content can reach about 60%. This technology has been applied to market present; b) sludge and calcium treatment technology, through the sludge dehydration lime mixing; heat to kill bacteria, reduce the moisture content, the passivation of heavy metals. The sludge treatment can be used for landfill cover soil materials, building materials; c) spiral rotary drying machine, the sludge water content of from 50% to 80% dry below after incineration; d) sludge composting technology automation control. The automation of composting process, realize the industrial automation production, mainly in control technology.
     Because investment for sludge disposal accounts for a very large proportion in the running and operation process of sewage treatment plants. Even, the proportion of sludge disposal is larger than that of sewage disposal. This situation makes sewage treatment plants only attach importance to sewage disposal and ignore the importance of sludge disposal. Because the facilities for sludge disposal are getting perfect, the scale for sludge disposal is getting larger and larger. The growing production of sludge and sludge issue have been severe problems which our country can not neglect. At present, the reclamation disposal and treatment work are still in the initial stage. We still mainly use landfill method while encouraging researching and developing of composting, and incineration. Through upgrading and developing the performance and sludge disposal equipment, relevant factories and engineers are trying to reduce the moisture content of sludge and running and operation cost in order to get good disposal effects. 

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