采用配方均匀设计法利用脱水污泥制备陶粒的研究

长期以来,对城市污水处理后产生的污泥处置一直是环保的难题,传统的处理处置方法均存在诸多问题,寻求一种好的处理处置污泥方法迫在眉睫。针对目前的问题运用带约束条件的配方均匀设计方法对粉煤灰-脱水污泥陶粒配方进行实验设计,运用三叶回转窑进行小试。研究了陶粒组分中粉煤灰、污泥、黏土的比例对烧成陶粒堆积密度、颗粒强度的影响;确定了最佳物料配比,使陶粒的性能测试指标均符合GB/17431.2-1998标准的规定。实验结果表明:烧制陶粒湿比例下脱水污泥用量达45%,干比例污泥用量15.2%,污泥减量化和资源化效果显著;陶粒浸出毒性实验结果表明各项指标均低于浸出液中危害成分浓度限值,达到了污泥无害化的效果;粉煤灰、污泥和黏土的优化质量(干)比例为79%,15.2%,5.8%;陶粒的堆积密度为600 kg/m3,筒压强度2.2 MPa,1 h吸水率10.2%,粒型系数1.3。

Application of formula uniform design for manufacture of haydite with sewage sludge

The disposal of sludge from urban sewage plants is a serious environmental problem, which will lead to secondary pollution if it is not well disposed. Since the traditional disposal methods have shortages, it is urgent to find a new approach to dispose the sludge. Aiming to the existing problems, the formula of haydite with coal fly ash and sewage sludge based on formula uniform restricted design theory was designed, a trefoil rotary kiln was used to make a test.The relationship between the ratio of haydite composition ingredients and loose bulk density was studied.The equation and datas fit well, and has a certain confidence level. The performance testing indicators meet the GB/17431.2-1998 standards. The results showed that haydite used 45% dewatered sludge in wet percentage, 15.2% in dry percentage, it was a significant effective for sludge reduction and resources reusing. The indexes of haydite identification tested for extraction toxicity are lower than extraction toxicity hazardous constituents concentration limits, sludge becomes harmless.The optimal percentage of the dry quality of fly ash,sludge,clay was 79%,15.2%,5.8%,respectively,bulk density was 600 kg/m³, cylinder compressive strength was 2.2 MPa, 1 h water absorption was 10.2%, grain shape coefficient was 1.3.