摘要
针对沼液中的悬浮颗粒物、氨氮、盐分等高浓度复杂组分,采用鸟粪石沉淀法进行预处理,探究鸟粪石沉淀预处理对膜浓缩工艺和污染物去除效率的影响。结果显示:鸟粪石沉淀预处理可降低沼液的浊度、电导率和氨氮浓度,并提高了后续超滤反渗透浓缩沼液的膜通量和浓缩倍数。超滤对沼液浊度的去除率大于99%,超滤透过液的浊度小于2.0 NTU。鸟粪石沉淀预处理提高了超滤膜对化学需氧量(COD_(Cr))的截留效率,同时也提高了反渗透膜对COD_(Cr)和盐分的截留效率。经鸟粪石沉淀预处理后,最终出水的COD_(Cr)、氨氮、电导率分别为135 mg·L^(-1)、21 mg·L^(-1)、0.16 mS·cm^(-1),出水水质优于对照组,且符合GB 5084—2021《农田灌溉水质标准》和GB 18596—2001《畜禽养殖业污染物排放标准》的要求。综上所述,鸟粪石沉淀法可作为膜法浓缩沼液的一种高效预处理方法。
Biogas slurry contains a large amount of suspended solids,organic matters and inorganic salts,which would cause serious membrane pollution and rapid decline of membrane flux during membrane concentration.In the present study,struvite precipitation was used as the pretreatment,to explore its effect on slowing down membrane fouling rate and improving the filtration efficiency of membrane.It is proved that after struvite precipitation,the turbidity,electrical conductivity and ammonia nitrogen concentration of biogas slurry are greatly reduced.The struvite precipitation increases the membrane flux and volume reduction factor of subsequent ultra filtration(UF)and reverse osmosis(RO).The turbidity removal efficiency of biogas slurry by UF is more than 99%,and the turbidity of UF permeate is less than 2.0 NTU.The struvite precipitation improves COD_(Cr)(chemical oxygen demand)removal rate of biogas slurry by UF,and enhances the removal efficiency of COD_(Cr) and salinity by RO.The COD_(Cr),ammonia nitrogen concentration and electrical conductivity of the final effluent are 135 mg·L^(-1),21 mg·L^(-1),0.16 mS·cm^(-1).All these quality parameters are better than those of the effluent without struvite precipitation,and satisfiy the limit of national standards of GB 5084—2021 Standard for irrigation water quality and GB 18596—2001 Discharge standard of pollutants for livestock and poultry breeding.It is confirmed that struvite precipitation is an efficient pretreatment for membrane concentration of biogas slurry.
作者
肖华
徐杏
谢传奇
周昕
周卫东
唐文升
XIAO Hua;XU Xing;XIE Chuanqi;ZHOU Xin;ZHOU Weidong;TANG Wensheng(Institute of Animal Husbandry and Veterinary Science,Zhejiang Academy of Agricultural Sciences,Hangzhou 310021,China;Institute of Animal Husbandry and Veterinary Science,Huangyan Bureau of Agriculture and Rural Affairs,Taizhou 318020,Zhejiang,China)
出处
《浙江农业学报》
CSCD
北大核心
2023年第6期1407-1415,共9页
Acta Agriculturae Zhejiangensis
基金
浙江省“领雁”研发攻关计划(2022C02045-3)
台州市黄岩区科技计划(2021043)
浙江省农业科学院地方科技合作项目(HY202003)
浙江省农业重大技术协同推广计划(2021XTTGXM02-3)。
关键词
沼液
鸟粪石沉淀
膜浓缩
超滤
反渗透
biogas slurry
struvite precipitation
membrane concentration
ultrafiltration
reverse osmosis
