The removal of high content of chlorides is a precondition of the utilization of municipal solid waste incineration fly ash. On the basis of the basic characteristics research such as chemical composition,content and leaching toxicityof heavy metals of the fly ash sample taken from some municipal solid waste incineration power plant in the North,China,this study investigates the effects of water-washing process parameters such as liquid-solid ratio,water-washing frequency,time and temperature on the removal of soluble chlorides in the fly ash. Meanwhile,surface morphology and crystalline phase composition of the fly ash before and after being washed are characterized. Results show that the optimum parameters for water-washing pretreatment are:normal temperature,liquid-solid ratio 8:1,10 min and one step respectively. Under these conditions,91.13% soluble chlorides in the fly ash can be removed. The liquid-solid ratio is the most important factor that influences the removal of soluble chlorides in the fly ash among all the factors,while the influence of water-washing fre-quency,time and temperature is relatively small.%城市生活垃圾焚烧飞灰中高含量氯盐的脱除是其资源化利用预处理的重要过程.以华北地区某垃圾焚烧发电厂的布袋除尘灰为样品,在对飞灰化学组成、重金属含量、浸出毒性等基本特性研究的基础上,考察了液固比、水洗次数、水洗时间以及水洗温度等工艺参数对氯离子洗脱率的影响;同时对水洗前后飞灰的微观形貌和晶相组成进行了表征.结果表明,水洗脱氯的最佳工艺参数为:常温条件下,液固比8:1,水洗10,min,1次水洗;在此条件下,飞灰中氯离子可达91.13%的洗脱率.液固比是影响氯离子洗脱率最主要的因素,水洗时间、水洗温度和水洗次数对其影响相对较小.
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