几种环境因子对循环水养殖系统中生物膜净化效率的研究

The influence of environmental factors on biofilter efficiency in a recirculating aquaculture system

为研究环境因子对生物膜水质净化效果,对爆炸棉为滤料的生物滤器进行了试验。采用优势菌种挂膜后,在不同水温、溶氧(DO)、盐度、p H条件下,研究生物滤器对人工加富的海水养殖废水水质的净化效果。结果显示,水温28℃时,化学需氧量(CODMn)、氨氮(NH4+-N)、亚硝酸盐氮(NO2--N)、磷酸盐(PO43--P)去除率分别为69.3%、93.7%、93.7%、19.4%;DO 6.00 mg/L时,CODMn、NH4+-N、NO2--N、PO43--P去除率分别为72.8%、91.7%、97%、15.6%;盐度25时,CODMn、NH4+-N、NO2--N、硝酸盐氮(NO3--N)、PO43--P去除率分别为57.1%、98.4%、99.9%、100%、42%;p H 7.5时,CODMn、NH4+-N去除率分别为72.8%、93.3%。研究表明,水温28℃、DO 6.00mg/L、盐度25和p H 7.5为该生物滤器最适水质净化条件,此时生物膜净化效率较高,出水水质较好。

The impact of environmental factors on water purification effect of biofiher in a recirculating aquaculture system （RAS） was studied. The experiment RAS was built with acrylic and plexiglass, and the biofilter was built with biochemical cotton fiber. The biofiher was inoculated with dominant bacteria until maturation. Purification experiment was done on enriched maricuhure wastewater, by studying the water quality indexes removal rate of the biofilter at different levels of temperature, dissolved oxygen （DO）, salinity, and pH. The results showed that when the water temperature was 28 ℃, the removal rate of CODMB, NH4 ＋- N, NO2 -- N and PO43-- P was 69.3%, 93.7%, 93.7% and 19.4% , respectively. When the DO was 6.00mg/L, the removal rate of CODMn, NH4＋- N, NO2-- N and PO43-- P was 72.8%, 91.7%, 97% and 15.6% , respectively. When the salinity was 25, the removal rate of CODM,, NH4＋- N, NO2-- N, NO3- - N and PO43-- P was 57.1%, 98.4%, 99.9%, 100% and 42%, respectively. When the pH was 7.5, the removal rate of CODMn and NH4 ＋- N was 72. 8% and 93.3%, respectively. It was observed that water temperature 28 ℃, DO 6.00 mg/L, salinity 25 and pH 7.5 were the optimum conditions for water purification of this biofiher in the experimental RAS. Under these conditions, the biofilter efficiency was higher, and the outlet water quality was better.