污泥热消化试验研究

Experimental Research on Sludge Thermophilic Digestion

污泥是污水处理的产物,成分复杂,如果处置不当会引起二次污染。污泥热消化可以使污泥达到稳定化和无害化。实验比较了在不同污泥浓度下,污泥高温好氧消化的效果,并且对污泥高温好氧消化和高温厌氧消化、高温厌氧消化和常温厌氧消化进行了比较,得出结果:低浓度的污泥(含水率约91.5%,VSS=38.6 mg/L)更有利于污泥的高温好氧消化,经过12 d的高温好氧消化,污泥各项指标:COD、VSS的降解率分别达到76.58%和50.2%,热消化中的高温(约50℃)可以去除污泥中的病原菌、病毒等,可以使污泥达到农用的标准;高温好氧消化和高温厌氧消化(都在低浓度污泥条件下)均可以使污泥达到稳定化,但经高温厌氧消化后的污泥有臭味;高温厌氧消化无论是在杀菌、杀病毒方面还是在产甲烷和氢气的速率方面等都要优于常温厌氧消化。

Sludge is the byproduct of wastewater treatment,its composition is complex and it will lead to secondary pollution if not well disposed.Sludge can be stability and harmlessness by sludge thermophilic digestion.During this experiment,the effect of sludge thermophilic aerobic digestion is compared in different sludge concentration.Sludge thermophilic aerobic digestion and sludge thermophlic anaerobic digestion,sludge normal temperature anaerobic digestion and sludge thermophilic anaerobic digestion are also compared.The result is that low concentration sludge（water content is about 91.5 %,VSS=38.6 mg/L） is good to sludge thermophilic digestion,after 12 d thermophilic digestion,the sludge indexes of COD and VSS are degraded into 76.58% and 50.2 % individually,the high temperature at thermophilic digestion can kill pathogenic bacteria and viruses in sludge which makes sludge be accorded with the sludge land use standards.Both thermophilic aerobic digestion and thermophilic anaerobic digestion in low sludge concentration can make sludge stability,but after thermophilic anaerobic digestion,sludge still has smelly.Thermophilic anaerobic digestion has more advantages than normal temperature anaerobic digestion whatever in killing bacteria aspect or the rate of producing methane and hydrogen aspect.