| The final disposition of city sewage sludge is always a major problem of environmental protection sector. With the accelerated process of urbanization, the sharp growth of urban sewage treatment, the rising rate of urban sewage treatment in China, municipal sludge disposal has become increasingly prominent. At present of the municipal sludge disposal, there are two main methods, namely, agricultural use and landfill. Agricultural use of sludge which accounts for about 44.3%, about 31% of landfill, about 11% of other methods, there is no disposal of approximately 13.7%.Sludge landfill sites need a large area and a lot of transportation costs, the foundation also required to prevent pollution of groundwater seepage. And the landfill is to some extent slowed down the process of this pollution, there is no fundamental solution to environmental pollution caused by sewage sludge. With the land-use restrictions, the decision of the landfill disposal of sludge will be phased out. Sludge incineration method and the degree of reduction of the highest degree of sound, but because of its sophisticated equipment, coupled with burning and generate a lot of smoke pollution and energy consumption of a number of problems limit the wide application of sewage sludge incineration technology. So the comprehensive utilization of sludge for sustainable development has become an inevitable trend.In this paper, a certain proportion of sludge and clay mixed brick conducted research for the topic, the calorific value of sludge in the brick process can effectively reduce the input of additional fuel, heavy metals are mostly in the high-temperature calcination process of the formation of a stable solid solution, which was solidified in the brick, will not overflow pollution of the environment, to achieve a sludge reduction, hazards, and resource utilization.The results show that the sludge and clay were dried, mixed brick screening process, the optimum mixing amount of sludge 15%, the best sintering temperature is 980℃-1040℃, and a high sludge sensitive materials, to strictly control the drying time. The brick can be obtained to meet the national standard, "Bricks" (GB5101-2003) of the relevant requirements, and to some extent it also improved the capability of heatproof. To meet the "municipal wastewater treatment plant sludge disposal The quality of sludge for brick" (CJ/T289-2008) standard requires the burning of sludge for brick-making must be less than 50% loss,On the requirements of the higher organic matter content of sludge to be first by the digestion of stabilized before they can use for follow-up brick building material.Add in the sludge-specific additives, to remove the unpleasant smell and heavy metal in the sludge. Using lime to absorb acid gases, add some activated carbon as adsorbent of heavy metals and dioxins, Use of circulating fluidized bed flue gas pollution tower and the bag filter to deal with sludge brick smoke pollution in the burning process.Due to a total ban on the use of clay bricks in large and medium cities in 2010, The investment costs and operating costs of the sludge project are very low, sludge reduction can be achieved, steady, sound and resource utilization, with significant economic and social benefits, so it has a very bright prospect.
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