Arts And Crafts’ Study On Making Permeable Brick By Municipal Sewage Sludge

In recent years, large numbers of municipal sewage treatment plants are built year byyear,and the ability has greatly improved to treat with municipal sewage.At the same time,accordingly a mass of sewage sludge are produced.However,the treatment to sewage sludge isdefective.Limited by technic and capital,there is a certain gap to the level of treatingharmlessly and completely.It would has threats and damage to the ecological environment. Inorder to reduce the adverse effects of sludge on the environment, reducing the running costsof the sewage treatment plant and protecting effectively to environment, sludge treatment anddisposal issue must be taken seriously,and this research direction bases on the pointmentioned above.Permeable brick as an excellent new building material，which has a certain compressivestrength and permeability performance,can be a good replacement to the unpermeable pavingmaterials and applied on roads、parks and squares in the urban areas. Because of its excellentphysical performance,and good affinity to surface soil,it is conducive to exchange moistureand heat between soil and atmosphere,and effective to mitigate the urban climateissues,such as reducing the heat island effect and maintenance of ecological balance.Research ideas in this subject is to try to make a application of sludge to buildingmaterials-the preparation of sludge permeable brick. Organic content in sludge ishigh,accounting for about50%of dry sludge capacity and its calorific value up to about12000kJ/kg. In the process of firing the permeable brick, the calorific value can be taken fulladvantage contained in sludge to reduce energy consumption. In the firing process, thatharmful organics can be oxidated effectively,harmful pathogens can be removed in the sludgeand heavy metal can be solidified in the brick body,sludge treatment can achieve thecompletely harmless level,which has a certain socio-economic benefits and environmentaland ecological benefits. In this paper, sludge from Yangling sewage treatment plant as aresearch object,through the research and discussion on a series of physical and chemicalproperties of sludge, provides a theoretical basis for the preparation of sludge permeablebricks.By controlling different levels and factors of the process of preparation for permeable brick,to seek the optimal point of integration about compressive strength and permeableproperties of permeable brick and to improve it’s performance levels. According to the resultsof this experiment, the sludge content and particle size of materials,is negatively related tocompressive strength,but the sintering temperature and holding time are positively correlatedto it; for the water permeability coefficient,there is a positive correlation to the sludge contentand particle size of materials,while negatively related to sintering temperature and holdingtime.The best arts and crafts of this research and practice process is with the ratio of rawmaterials (sludge:clunch:cinder=16%:74%:10%),calcinations temperature of1100°C andholding time of1.5h,which can produce sludge permeable bricks with better performance...