Effect of leachate recycling and inoculation on the biochemical characteristics of municipal refuse in landfill bioreactors

Activity development of key groups of enzymes involved in municipal refuse decomposition was measured in laboratory landfill bioreactors with and without leachate recycling and inoculation for about 210 days.The results showed that the enzymes(amylase,protease,cellulase,lipase and pectinase)were present in fresh refuse but at low values and positively affected by leachate recycling and refuse inoculation.The total average of cellulase activity in digesters D3 operated with leachate recycling but no inoculation,D4 and D5 operated with leachate recyling and inoculation was much higher than that in digesters D1 and D2 without leachate recycling and inoculation by 88%-127%,117%-162%and 64%-98%.The total average of protease activity was higher in digester D4 than that in digesters D1,D2,D3and D5 by 63%,39%,24%and 24%,respectively,and the positive effect of leachate recycling and inoculation on protease activity of landfilled refuse mainly was at the first two months.The total average of amylase activity was higher in digesters D3,D4 and D5 than that in digesters D1 and D2 by 83%-132%,96%-148%and 81%-129%.During the early phase of incubation,the stimulatory effect of inoculation on lipase activity was measured,but refuse moisture was the main factor affecting lipase activity of landfilled refuse.The inoculation,initial and continuous inoculation of microorganisms existing in leachate,was the mainly stimulatory factor affecting pectinase activity of landfilled refuse.     

高梯度磁分离技术在环境保护中的应用

本文概述了近二十多年来国内外对高梯度磁分离技术在废水、废气、废渣处理中的应用及研究进展情况，并展望了该技术在“三废”治理中的应用前景。     

硫酸钙废渣制石膏的技术方法

以硫酸钙渣为对象，对废渣的化学成份和理化性能做了分析，并对废渣有效处理后制石膏的工艺做了探讨实验，提出了首先去除废渣中的有机杂质后再用压蒸的方法制石膏，制出的石膏与国家标准对比，可达三级石膏，在工农业上可广泛应用。     

柠檬酸生产废渣的综合利用

在柠檬酸生产过程中排出的废渣有压滤工序产生的菌丝体废渣和酸解工序产生的硫酸钙废渣。每生产１吨柠檬酸，产生菌丝体废渣２．３吨左右，硫酸钙废渣１．２吨右左。目前，全国各生产厂每年排出这两类废渣高达１０余万吨，大多不加任何处理或利用，任意堆放或用水冲入河道，造成污染。因此，这些废渣的综合利用是一个很值得重视的问题。一、菌丝渣的利用菌丝渣中的主要成分为菌丝体、残糖、纤维素等物质，除此之外，还含有少量维生素及各种酶，它可作如下几个方面的利用。１．用厌氧发酵法制取沼气菌丝体渣含有一定数量的蛋白质、脂肪、纤维…     

钢渣的处理与利用

一、概论钢渣产自炼钢过程,其主要成份有:CaO、SiO_2、Al_2O_3、FeO、Fe_2O_3、MgO、MnO、P_2O_5、f-CaO等,根据矿石成份,有时还可能有V_2O_5、TiO_2等.在表1中列入我国某些钢厂钢渣的化学成份.钢渣的产率根据金属炉料、炼钢辅料、冶炼设备、炉衬情况的不同而有所差别.由于我国炼钢原料中生铁所占的比例较大,故产渣率也较高.我国每炼     

用液膜技术处理含铬废水的研究

采用ＴＢＰ－ＳＰａｎ８０－煤油液膜体系处理含铬废水，在优化条件下经过１０ｍｉｎ的液膜分离，铬离子浓度可由１５２ｍｇ／Ｌ降至０．５ｍｇ／Ｌ以下，达到国家规定的排放标准。     

电解处理含钒、铬废水研究

钒渣提钒废水含钒含铬呈酸性,采用电解法处理可以一步完成六价铬和五价钒的净化脱除反应。铁阳极电化学溶解产生的Fe~(2+)将Cr~(6+)还原成Cr~(3+),VO_2~+与铁、铬的三价氢氧化物吸附共沉,净水先滤除沉渣后经石灰乳化水中和排放。排放水V_2O_5<1mg/L、Cr~(6+)<0.5mg/L、pH为8。电解沉渣中V_2O_5>2%,不外加钠盐,采用常规焙烧-水浸工艺回收V_2O_5,其收益可全部抵消水处理费用。本文介绍电解法实验室试验及扩大试验的结果,并探讨电解讨程钒、铬同时净化脱除原理。