Experimental Analysis on Preparation of Fired Brick with Shale and Sewage Sludge
FAN Ying-ru,DENG Cheng,LUO Hui,CHEN Wei and QIAN Jue-shi
DOI:10.11835/j.issn.1674-4764.2012.01.025
Received ,Revised , Accepted , Available online July 01, 2015
Volume ,2012,Pages 130-135
- Abstract
The effects of sewage sludge dosage and firing temperature on the performance of fired shale sample were investigated experimentally. The volatilization of heavy metals in the firing process and the heavy metals solidification of fired sample, were studied by means of selecting three representative heavy metals and using excess heavy metals mixed with sludge and shale. The results show that when the sewage sludge dosage is 30% and the firing temperature is at 900℃, the compressive strength of fired shale sample could reach more than 10MPa. The addition of sewage sludge is beneficial to improve the plasticity of brick mixture and significantly reduce the bulk density of fired shale sample, whilst it can also increase the drying and firing shrinkage. The dosage of sludge should be controlled within 30%, and firing temperature should be controlled between 900~1000℃. Addition of sewage sludge will make fired shale sample efflorescent, and the more dosage of sewage sludge, the more serious efflorescence. Increasing the firing temperature can be suppressed the efflorescence to some extent. In the firing process of fired sample with sewage sludge and shale, the volatilization of heavy metals is far less than the sintering process of pure sludge incineration. The leaching concentrations of total copper, total chromium and total lead which come from fired sample made of shale and sludge are all within safety standards of the leaching toxicity.