煤矸石制备4A分子筛处理垃圾渗滤液

PREPARATION AND APPLICATION OF 4A MOLECULAR SIEVE FROM COAL GANGUE IN LANDFILL LEACHATE

煤矸石中铝、硅主要以高岭土形式存在,活性非常低。通过添加碳酸钠在一定温度下焙烧煤矸石,使煤矸石中的氧化铝和氧化硅完全的转化硅铝酸钠,然后把活化煤矸石、铝酸钠、氢氧化钠和蒸馏水按硅铝摩尔比为2、钠硅摩尔比为1.8和水钠摩尔比为42混合在一起,通过正交试验确定影响4A分子筛性能的因素,并在常温下,用合成的4A分子筛处理渗滤液。试验表明,碳酸钠与煤矸石质量比为1.1、活化温度为800℃、活化时间120 min、晶化温度80℃和反应时间180 min,在条件下测定钙交换能力为310 mg/g。在100 mL渗滤液中加入13 g 4A分子筛,吸附40 min,可以使氨氮和COD的去除率分别为78.2%和75.6%。

The kaolin form of aluminum-silicon in coal gangue has low activity reactivity.The coal gangue added sodium carbonate is sintered at a giv en temperature,aluminum and silicon is converted to sodium silico-aluminate,according to 2 of n（SiO2）/n（Al2O3） and 1.8 of n（Na2O）/n（SiO2） and 42 of n（H2O）/n（Na2O）,the activated coal gangue and sodium aluminate and sodium hydroxide and distilled water are mixed together,the factors that can affect performance of 4A molecular sieve are optimized by orthogonal experiment,at the same time,the 4A molecular sieve as adsorbent is treated landfill leachate in ordinary temperature.The results show that the mass ratio of sodium carbonate to coal gangue is 1.1,the roasting activation temperature is 800 ℃,the roasting activation time is 120 min,the crystallization temperature is 80 ℃,the crystallization time is 180 min,and the exchange ability of calcium is 310 mg/g.When adsorption time is 40 min,the optimum ration of dosage of 4A molecular sieve to landfill leachate is 13 g,the removal rate of ammonia nitrogen is 78.2%,and the removal rate of COD is 75.6%.