In order to clarify the effects of different ambient temperature conditions on dewatered sludge composting. Temperature of bioreactor was controlled by water bath, and experiment operated at 10℃ (CT10) and 25 ℃ (CT25) respectively for 30 days. Temperature, pH, TN, C/N and humic acid were analyzed during composting process. The results showed that temperature of compost achieved above 55℃ and maintained for 8 days at condition CT25, and temperature achieved to 55℃ for 3 days in advance and maintained more than 3 days compared with CT10; the range of variation of pH value between 7.10 to 7.91, and rised first and falled later, and the pH change of CT25 was faster than CT10 during the composting; organic matter and total nitrogen content was reduced during composting process, compared with CT10, the contents of above two indexs of CT25 were lower at the same sampling time, organic matter content showed a significant difference between the two treatments on 18th day sampling time (P<0.05), but the total nitrogen content of different treatments showed no significant difference (P<0.05). Humic acid content showed an increasing trend during composting process, although there was no significant difference between the two treatments at the same sampling time (P<0.05), but by the end of operation, humic acid content of CT25 was 24.8%, and 5.52% more than CT10, Through theT value (T=[(C/N)end/(C/N)start<0.6)] to determine the sludge maturity degree of two treatments showed that eighteenth days CT25 treatmentT value was 0.59, the compost reached maturity, CT10 treatment in thirtieth day until maturity. These above results showed that the higher start-up temperature was in favour of sludge composting. Therefore, the control of start-up temperature can be used to speed the sludge composting, especially at low temperature.%为明确不同环境温度对脱水污泥堆肥效果的影响,试验采用双层反应器进行水浴保温模拟不同环境温度,分别设置10℃(CT10)和25℃(CT25)两个处理并运行30 d,通过分析污泥堆肥过程中温度、pH、总氮、C/N比值、腐殖酸含量等指标变化特征,比较两个处理的污泥腐熟效果.结果表明:CT25堆肥处理进入55℃高温期并维持8 d,较CT10处理提前3 d达到高温期并多维持3 d;两个处理堆体的pH值变化范围为7.10~7.91,呈先升后降趋势,且CT25处理pH值的升高、降低幅度更大;两种堆肥处理有机质和总氮含量呈降低趋势,且同一时期CT25处理低于CT10,其中18 d取样时两处理有机质含量呈显著性差异(P<0.05),两处理总氮在堆肥各时期没有呈现显著差异(P<0.05);整个运行期间,堆体腐殖酸含量呈增加趋势,堆肥结束时,CT25处理的腐殖质含量达24.18%,较CT10处理提高5.52%;通过T值(T=(C/N)终/(C/N)始<0.6)判断两处理的污泥腐熟程度,结果显示,第18天时CT25处理的T值为0.59,堆体达到腐熟,CT10处理在第30天时才达到腐熟.上述结果表明,利用该反应器进行脱水污泥堆肥,较高温度启动可以实现污泥更快速、充分腐熟.通过对脱水污泥堆肥反应器启动温度的控制,可为低温条件下脱水污泥的快速腐熟控制提供参考.
展开▼
