沸石吸附氨氮辅助鸟粪石法去除养猪废水营养物质

Nutrient Removal from Swine Wastewater by Struvite Precipitation with Ammonia Adsorption on Zeolite

利用镁盐为沉淀剂,以鸟粪石沉淀的形式去除养猪废水中的氮、磷,同时采用天然斜发沸石吸附法来提高氨氮的去除效果,以及曝气吹脱CO2方式提高溶液的pH值。考察了沸石投加量、镁盐投加量、曝气时间及初始pH等因素对氨氮和磷酸盐去除效果的影响。结果表明,对于原养猪废水（pH=7.51）,在沸石投加量为0.5 g/L,Mg/P摩尔比为1.4：1,曝气时间为50 min的条件下,pH值随着曝气时间的延长而逐渐升高,最高可达8.7左右,氨氮和磷酸盐的去除率分别为74.7%和72.6%;当初始pH控制为8~9时,正磷酸盐去除率达到88.7%~92.1%,氨氮去除率为72.5%~76.2%。

By using magnesium salt as settling agent and increasing solution pH by CO2 degasification, nitrogen and phosphorous in swine wastewater were removed as struvite precipitate, and the removal rate of ammonia-nitrogen was improved by natural clinoptilolite adsorption. Effects of zeolite dosage, magnesium salt dosage, aeration time, initial solution pH on phosphate and ammonia removal were investigated. Experimental results indicated that under the optimal reaction condition of zeolite dosage 0.5 g/L, Mg/P molar rate 1.4 ： 1, aeration time 50 min, the ammonium-nitrogen and phosphate removal rates of swine wastewater with pH gradually increasing up to about 8.7 reached respectively about 74.7% and 72.6%. By increasing the initial pH up to 8-9, the phosphate and ammonium-nitrogen removal rates of swine wastewater reached 88. 7%-92.1% and 72.5%-76.2% respectively.