摘要
为回收剩余污泥水解酸化液中的营养元素与有机质,构建了白云石-水解酸化液钙镁溶出体系,获得富含钙镁的溶出液,控制溶出液反应pH和反应时间进行第1阶段回收,以回收后的上清液进一步作为钙镁源从水解酸化液中进行第2阶段回收。结果表明,钙镁溶出的适宜条件为酸化pH 4.0~4.5、白云石颗粒50~80目、固液比3∶100（每100mL水解酸化液中投加3g筛分后白云石）、溶出时间10h;第1阶段回收适宜的反应pH为8.5,氮（以氨氮计）回收率、磷（以可溶性正磷酸盐（以P计）计）回收率分别为10.24%和95.89%;第2阶段回收适宜的镁磷摩尔比为0.60、反应pH为9.0,此时氮、磷回收率分别为14.60%和83.91%;傅立叶红外变换（FTIR）和电感耦合等离子直读光谱（ICP）分析表明,回收产物主要由无机养分和有机质组成,重金属含量极少。利用白云石提供钙镁源能经济有效地回收剩余污泥水解酸化液中的氮、磷等营养元素,同时回收有机质,回收产物品质符合《有机-无机复混肥料》（GB 18877—2009）中Ⅰ型肥料要求。
In order to recover the nutrients and organic matter from the hydrolysis-acidification liquor of excess sludge,the calcium and magnesium dissolution system of dolomite-hydrolysis and acidification liquor was established to obtain dissolution liquor containing rich calcium and magnesium.The first-stage recovery from the dissolution liquor was conducted by controlling reaction pH and reaction time,and the supernatant after the first-stage recovery was further used as source of calcium and magnesium for the second-stage recovery from the hydrolysis-acidification liquor.The experimental results showed that,the appropriate dissolution conditions were acidification pH 4.0-4.5,dolomite mesh 50-80,solid/liquid ratio 3∶100（3g screened dolomite per 100 mL hydrolysis-acidification liquor）and dissolution time 10 h,the nitrogen（ammonia nitrogen）and phosphorus（in soluble phosphate）recovery rates for the first-stage recovery were 10.24% and 95.89%respectively when the appropriate reaction pH was 8.5,and the nitrogen and phosphorus recovery rates for the second-stage recovery were 14.60% and 83.91% respectively when added Mg/P molecular ratio was 0.60 and reaction pH was 9.0.Based on Fourier Transform Infrared Spectroscopy（FTIR）and Inductively Coupled Plasma（ICP）analyses,the recovered product was mainly composed of inorganic nutrients and organic matter with extremely low amount of heavy metals.This research indicated that the nutritional elements such as nitrogen and phosphorus as well as organic matter could be economically and effectively recovered from the hydrolysis-acidification liquor of excess sludge by utilizing dolomite providing calcium and magnesium sources,and the qualities of the recovered products accorded with the requirements of typeⅠ fertilizer in China national standards of Organic-Inorganic Compound Fertilizers（GB 18877-2009）.
出处
《环境污染与防治》
CAS
CSCD
北大核心
2014年第11期30-35,共6页
Environmental Pollution & Control
基金
国家"十一五"水专项子课题资助项目(No.2009ZX07101-15)
江苏省普通高校研究生科研创新计划项目(No.CXLX13_531)
江苏高校优势学科建设工程资助项目(No.PAPD)
关键词
剩余污泥水解酸化液
白云石
营养元素
有机质
复混肥料
hydrolysis-acidification liquor of excess sludge
dolomite
nutritional element
organic matter
compound fertilizer
