不同固化剂的优化配置及对城市污泥的固化效果研究

Research on the Optimal Configuration of Different Sludge Curing Agentand their Application in the Solidification of Municipal Sludge

目前我国的污泥处置方式以卫生填埋为主,而污泥含有多种对人体有害的病原微生物、寄生虫卵、重金属及某些难降解的有机物等,因此卫生填埋前需经适当的预处理。指出了固化技术是一种比较成熟的废物处置技术,对污泥进行固定化处理可以使污泥具有一定抗压强度,并可有效地抑制污泥中的有害物质对环境的潜在危害,有利于污泥进行填埋处理。该技术具有处理时间短、适用范围较广等优势,十分适合用于污泥填埋的预处理。研究表明:水泥、粉煤灰、氯化钙、β-萘系减水剂组成的固化剂对市政污泥有较好的固化效果。经过试验,确定了其最佳用量为:每100 g脱水污泥(含水率80%)掺加20 g水泥、15 g粉煤灰、0.4 g氯化钙、0.2 gβ-萘系减水剂;在最佳固化剂用量下,固化污泥养护7 d、14 d、28 d的抗压强度分别可达0.83 MPa、1.22 MPa、1.52 MPa。

The production of sludge in China is growing rapidly and sanitary landfill is the main method of sludge disposal.While the sludge contains a variety of harmful pathogenic microorganisms,heavy metals and some difficult-to-degrade organic matters,proper pretreatment is required.The solidification technology is a common disposal method,which can make the sludge have a certain compressive strength and effectively inhibit the potential harm to the environment.Compared with other technologies,solidification treatment has the advantages of in-time treatment and wide application range.In this work,it can be found that the combination of cement,fly ash,calcium chloride,andβ-naphthalene series water reducing agent has a good curing effect on municipal sludge.Furthermore,it is determined that the optimal dosage is 20g of cement,15g of fly ash,0.4g of calcium chloride and 0.2gβ-naphthalene series water reducing agent in 100 g of dewatered sludge(water content of 80%).Under the optimal dosage,the compressive strength after solidification for 7 days,14 days,and 28 days can reach 0.83 MPa,1.22 MPa,and 1.52 MPa,respectively.