摘要
以绍兴污水处理厂脱水污泥为研究对象,通过实验分析了污泥进行干化焚烧处理的可行性。对污泥泥质进行分析,采用桨叶式污泥干化机对污泥的热干化特性、干化过程污染排放特性进行研究,使用流化床污泥焚烧试验装置对污泥焚烧工况及焚烧过程中污染物的排放特征进行研究,结果表明,绍兴污水处理厂脱水污泥的泥质特征与大多数污水污泥类似,灰分较高、发热量较低,需干化后才可实现稳定燃烧;污泥在小型桨叶式污泥干化机内的干化速率最高达到0.6kg/(m2·min),并随污泥干化的进行而逐渐降低;干化过程产生的常规污染气体中氨气浓度最高,可达170 mg/Nm3;污泥干化冷凝水的COD高达820 mg/L,氨氮等指标也很高。污泥干化系统的设计需充分考虑污泥热干化过程中气体和液体污染物的排放,设置相应的处理设施。污泥干化至含水率30%时,可在不投加辅助燃料的情况下实现流化床焚烧炉内的焚烧处理,干化污泥焚烧时需关注烟气中常规污染气体和重金属的控制,焚烧灰渣浸出毒性未超过国标限值。
Experiments were carried out in a paddle sludge drying machine and a fluidized bed incinerator to analyze the feasibility of drying and incineration treatment of sewage sludge from Shaoxing Wastewater Treatment Plant(WTP).The sludge natures,as well as the contaminants emission during the treatment process were detected.Results show that,the sludge from Shaoxing WTP has similar characteristics with other sewage sludge,as the ash content is relativily high and the heating value is relativily low.The drying rate can reach up to 0.6 kg/(m2·min) in the small paddle drying machine and a drop of drying rate also appear during the process.The concentration of ammonia,which is the main pollution gas during the sludge drying process,can reach up to 170 mg/Nm3.The condensate from sludge drying process should be treated before discharge,as its COD can reach up to 820 mg/L.Sewage sludge from Shaoxing WTP would combust without any auxiliary fuel when its water content is lower than 30% after drying.The noxious gases and heavy metals in the flue gas should be taken seriously.The leaching toxicity of sludge incineration ash is below the national standard limits.
出处
《环境工程学报》
CAS
CSCD
北大核心
2012年第10期3399-3404,共6页
Chinese Journal of Environmental Engineering
基金
国家重点基础研究发展(973)计划(2011CB201506)
水体污染控制与治理科技重大专项资助(2009ZX07317-003)
国家高技术研究发展计划(863)项目(2009AA064704)
浙江省重大科技专项资助项目(2007C03003)
关键词
污泥
污泥干化焚烧
污泥处理
sewage sludge
sludge drying and incineration
sludge treatment