海水养殖废水预处理方法与微藻藻种筛选

摘要

为加强养殖废水处理与循环利用，比较了22～27℃下利用4种方法（过滤养殖废水即对照组、加热法、臭氧消毒法和次氯酸钠消毒法）预处理的大西洋鲑养殖废水中小球藻、盐藻、三角褐指藻和湛江等鞭金藻4种常用饵料微藻的生长，探讨养殖废水预处理方法对微藻生长的影响及优质藻种的筛选。试验结果表明，4个试验组中小球藻生长良好，其他3种藻在加热组与次氯酸钠消毒组生长较好，臭氧组因浮游生物滋生藻种沉降或死亡。4种微藻对各组废水中磷的去除效果（76％～99％）明显；湛江等鞭金藻对氮（硝酸氮）的去除率比其他3种藻类低，仅为28％～59％；次氯酸钠消毒影响了4种藻对氮的去除（28％～81％），但磷的去除率均在95％以上。综上，次氯酸钠消毒养殖废水适宜微藻的生长，但会影响藻类氮的去除效果；小球藻在4种方法预处理养殖废水中的生长及氮、磷去除效果均较好，适宜规模化培养。%The growth was compared in algae Chlorella spp ., Dunaliella salina , Phaeodactylum tricornutum and Isochrysis zhanjiangensis cultivated in effluents from Atlantic salmon (Salmo salar) mariculture pretreated by different methods including heating ,ozone disinfection and sodium hypochlorite disinfection to screen microalgae for large-scale cultivation ,and to enhance the efficiency of mariculture effluent treatment and recirculating utilization . The results showed that Chlorella spp . showed good growth in the effluents unpretreated and pretreated by the three methods .The other three species of algae were found to grow well in the effluents pretreated by heating and sodium hypochlorite disinfection ,but P .tricornutum ,I .zhanjiangensis and D .salina soon settled or died due to plankton emergence in the ozone disinfection group .The four species microalgae had P removal rate of 76% -99% in the effluents , with the minimal N (nitrate) removal rate (only 28% -59% ) by I .z hanj iangensis .Sodium hypochlorite disinfection led to low N removal (28% -81% ) by the four species of microalgae ,but P removal rates were more than 95% in this group .In conclusion ,mariculture effluents disinfected by sodium hypochlorite is suitable for microalgae grow th , but affect nitrogen removal . According to biomass production and nutrient removal , Chlorella spp . would be good candidate for large-scale cultivation in mariculture effluent .