利用白云石提供钙镁源从污泥厌氧消化液中回收磷  

PHOSPHORUS RECOVERY FROM ANAEROBIC DIGESTION SUPERNATANT OF SEWAGE SLUDGE BY WAY OF DOLOMITE PROVIDING CALCIUM AND MAGNESIUM SOURCES

作　　者：梅翔[1] 王欣[1] 杨旭[1] 何珣[1] 夏红艳[1] 吴芳芳[1] 

机构地区：[1]南京林业大学化学工程学院环境工程系,江苏南京210037

出　　处：《水处理技术》2012年第12期48-53,共6页Technology of Water Treatment

基　　金：国家"十一五"水专项子课题资助(2009ZX07101-15);江苏省研究生培养创新工程资助项目(苏教研[2010]6号);江苏高校优势学科建设工程资助项目(PAPD)

摘　　要：为探讨利用白云石提供钙镁源从污泥厌氧消化液中回收磷并获得富磷回收产物的工艺方法与条件,采用白云石为填料的钙镁溶出系统,考察了系统在不同的厌氧消化液进液流量、气水体积比、体积回流比条件下运行9 h后溶出的Ca2+、Mg2+浓度状况及在反应pH=9.0时的磷回收效果。试验结果表明,白云石钙镁溶出系统适宜的工艺条件为进液流量2.0 BV/h、气水体积比20.0和体积回流比5.0,溶出液Ca2+、Mg2+浓度分别为230.01 mg/L和76.30mg/L,厌氧消化液磷回收率达到97.35%,氨氮回收率12.97%,回收产物的含磷率(以P2O5计)和含氮率分别为40.78%和0.20%。经XRD、FTIR、SEM和EDS分析表征,回收产物以磷酸钙盐和磷酸铵镁为主要成分。研究表明,利用白云石提供钙镁源可以有效地回收污泥厌氧消化液中的磷并回收部分氮,且回收产物含磷率高,杂质少。In order to explore the suitable process methods and conditions for recovering phosphorus from anaerobic digestion superuatant of sewage sludge and obtaining phosphorus-rich recovered product by way of dolomite providing calcium and magnesium sources, the dissolution system of calcium and magnesium with dolomite as packed material was adopted. The dissolution situations of Ca^2＋ and Mg^2＋ concentrations after 9-hour running, and the performances of recovering phosphorus at the reaction pH 9.0 were investigated under the conditions of different influent flow rates, air/water ratios and recirculation ratios. The experimental results showed that the appropriate process conditions for the dissolution system of calcium and magnesium were that the influent flow rate, the air/water ratio and the recirculation rate were 2.0 BV/h, 20.0 and 5.0 ,respectively, and Ca2＋ and Mga~ concentrations of the dissolution liquor were 230.01 mg/L and 76.30 mg/L, respectively. The recovery rates of phosphorus and ammonium-nitrogen were 97.35% and 12.97%, respectively, and the contents of phosphorus （as P205） and nitrogen of the recovered product were 40.78% and 0.20%, respectively. Based on the analyses and characterization ofXRD, FTIR, SEM and EDS, the main components of recovered products were calcium phosphates and magnesium ammonium phosphate. This research indicated that the utilization of dolomite for providing calcium and magnesium sources could effectively recover phosphorus and partial nitrogen from anaerobic digestion supernatant, and the phosphorus content of the recovered product was high with less impurity.

关 键 词：污泥厌氧消化液 磷回收 白云石 钙源 镁源 磷酸钙盐 磷酸铵镁 

分 类 号：X703.1[环境科学与工程—环境工程]