Reading guidance：With development of sewage treatment plants, disposal degree is getting better and better. The discharge amount of residual sludge is getting more and more. At present, the sewage treatment plant sludg

   With development of sewage treatment plants, disposal degree is getting better and better. The discharge amount of residual sludge is getting more and more.
   At present, the sewage treatment plant sludge generated, most simply after dehydration at the disposal of transport, only a few to be standardized disposal. The sludge composition is very complex, is an aggregation of organic and inorganic zooglea formed by microorganisms and the adsorption of the sludge. Besides a large quantity of water, organic refractory, heavy metals and salts, and a small amount of pathogenic microorganism and parasite eggs. A lot of without any treatment of the sludge piled up and emissions, causing new pollution to the environment. If the discharge of sludge will become the two pollution source, through dangerous atmosphere, groundwater and soil medium into the food chain, a serious threat to human health. Therefore, how to scientific production, processing of complex sludge, make it harmless, resources, has become an important work of environmental protection and the relevant departments.
   Making brick with sludge is a technology of sludge resource utilization in. It makes full use of the useful component in the sludge, to realize the waste to treasure, in line with the strategic policy of sustainable development, is conducive to the establishment of recycling based economy, to eliminate sludge potential harm to the environment, reduce the sewage treatment plant operating costs, while reducing the clay mining, alleviate the contradiction between the brick and tile industry and agriculture contend for the soil.
   Application of sewage sludge in sintering products, brick by brick, the reason is its high strength, strong durability, green environmental protection, no radiation and so on performance. The sludge for brick making process: sludge - concentration before treatment, dehydration, drying, sintering brick and tile products. Sludge treatment and brick making process, not only environmental benefits, social benefits and economic benefits of a comprehensive trade-off, but also a variety of treatment process were analyzed and assessed, according to the actual situation were selected.
   Utilization of sludge has the characteristics of high thermal mass and light, and successfully developed a lightweight brick. The light brick radioactive indicators meet the requirements of the < building materials radiation health protection standard >, brick of the main indicators reach the national standard of fired common brick, has high compressive strength, save 10% of energy consumption, weight than the same volume of ordinary brick light, and save the advantages of clay resources 10%  to 15%.
   Sludge can be made into ordinary building eco brick. The sludge ecological brick is in clay brick making raw materials adding 10% sludge and fired at 900 DEG C, to achieve the best effect. Even the sludge accounted for 30% of the ecological brick, this process can still be achieved. This method not only and sludge, still firing process will toxic heavy metals are sealed in the sludge, killing all harmful bacteria and organic matter and the brick no peculiar smell.
   Municipal sewage sludge as part of the raw materials for preparation of sintering brick, of different sintering temperature, different dosage of sewage sludge sintering brick physical, mechanical properties were research and analysis. Results show, and the sludge can be used for the preparation of sintering brick, when the dosage of sewage sludge is less than or equal to 12%, the sintering temperature is 1100 DEG C, sintering and the physical and mechanical properties of sintered brick are in line with standard sintered brick. Firing temperature, with the increase of the dosage of sewage sludge, reduce the density of sintered brick, water absorption increased, compressive strength decreases. Sludge dosage must, with the increase of sintering temperature, increasing the density of sintered brick, water absorption decreased, compressive strength increases.
   It is shown in research that Burning temperature of 1100 DEG C, sludge content was 12% of sintered brick, after roasting leaching amount of heavy metals have different degrees of reduction, which reduce the volume of the largest for Zn (96.30%), at least for C r20.14%, and by measuring the leaching concentrations of heavy metals were much lower than < dangerous hazardous waste identification standard leaching toxicity identification > standard requirements, containing heavy metal sludge for brick making, good effects on the solidification of heavy metals in sludge, safe and feasible.   
   As raw materials for producing bricks, in high temperature roasting, equal to the sludge harmless, decrements and resource processing. In the brick, sludge containing a certain calorific value of organic matter (per kilogram of water rate for about 35% of the sludge and burning can produce 2000 ~ 3000kcal heat). This and supplement the brick in the high temperature roasting heat, reduces the energy consumption (2.5kg water rate of 35% of the sludge is equivalent to 1 kg of standard coal). So, sludge brick is conducive to the development of circular economy, but also reflects the requirements of waste processing resources and industrialization, but also conforms to prohibits the damage field of brick and farmland conservation principle.
  Therefore, taking advantage of municipal sludge to make bricks has a good prospect. The state also support brick extensive collection of raw materials, to some of the policy of subsidy, sludge brick is worthy of promotion.
 
   
 
   
   

：Summary of sludge disposal technology in hospital ：Comments on final disposal method for sludge