脱硫石膏耦合微波对生产燃料乙醇厌氧消化污泥脱水性能的影响

Enhancing dewaterability of fuel ethanol producing anaerobic digestion sludge by microwave combined with desulfurization gypsum

为使污泥脱水后资源化农用,利用微波在不同功率(800、640和560 W)和时间(60、120和180 s)条件下,耦合脱硫石膏(2、4、6和8 g·L^(-1))对燃料乙醇厌氧消化污泥(ADSFE)脱水性能改善进行研究,探讨其脱水效果及相关机理。结果表明,最佳条件是脱硫石膏(6 g·L^(-1))耦合微波(640 W,120 s)处理。在最佳处理条件下,污泥比阻(SRF)下降至1.05×10^(12)m·kg^(-1),与原污泥相比降低了87.5%,与单独加入脱硫石膏相比降低了77.80%,与单独微波调理相比降低了75.60%。此外,扫描电镜(SEM)表明耦合调理后的ADSFE形成致密且具有较大孔径的絮体,易实现固液分离;热重(TGDTG)曲线显示,脱水起始温度和热重峰明显前移。因此,脱硫石膏与微波协同作用调理ADSFE时,脱水性能明显改善并优于单独调理的效果。同时,处理后污泥有机质含量满足有机肥制备原料要求。

In order to make the sludge dewatering as agricultural resources,microwave in different power （800,640 and 560 W） and time （60,120 and 180 s） coupled with desulfuration gypsum （2,4,6 and 8 g·L^-1） was used to improve the dewaterability of fuel ethanol producing anaerobic digestion sludge.The improvement effect and related mechanism were discussed.The results showed the optimal condition was at desulfurization gypsum （6 g·L^-1） coupled microwave （640 W,120 s）.At the optimum processing conditionss Specific resistance to filtration （SRF） decreased to 1.05 × 10^（12）m·kg^-1,reduced by 87.5% compared with the original sludge,by77.80% compared with adding desulfurization gypsum and 75.60% compared with microwave alone.In addition,after coupling treatment,scanning electron microscopy （SEM） showed that the flocs tended to be dense and with larger pore size,easy solid-liquid separation.Thermogravimetric （TG-DTG） curves showed that the initial temperature and thermal dehydration peak moved forward.Therefore,with the synthetic effect of desulfurization gypsum and microwave,dewatering performance is obviously improved and better than a separate conditioning effect.At the same time,the organic matter content of sludge can meet the requirement of raw material preparation after treatment.