| 酸-碱预处理促进剩余污泥厌氧消化的研究 |
| 摘要点击 2662 全文点击 1624 投稿时间：2011-08-08 修订日期：2011-10-27 |
| 查看HTML全文
查看全文 查看/发表评论 下载PDF阅读器 |
| 中文关键词 剩余污泥 酸-碱预处理 厌氧消化 甲烷 污泥减量化 |
| 英文关键词 excess sludge acid-alkali pretreatment anaerobic digestion methane sludge reduction |
|
| 中文摘要 |
| 为提高剩余污泥的厌氧消化效率,投加酸和碱对污泥进行预处理,对比分析了不同预处理方式(单独碱处理、酸-碱处理和碱-酸处理)对污泥水解酸化的影响,并研究了各种预处理方式对后续厌氧消化产甲烷效率的影响.结果表明,单独碱处理的溶解性化学需氧量(SCOD)溶出量比酸碱联合处理要大16%左右,预处理第8 d,达到5406.1 mg·L-1.采用先酸(pH 4.0, 4 d)后碱(pH 10.0, 4 d)预处理,在污泥水解酸化过程中,乙酸产量及其占总短链脂肪酸(SCFAs)的质量分数均高于其他预处理方式,其乙酸产量(以COD/VSS计)可达到74.4 mg·g-1,占总SCFAs的60.5%.酸-碱预处理后污泥混合液的C∶N比值为25左右,C∶P比值在35~40之间,这比单独碱处理和碱-酸处理后的C∶N和C∶P比值更有利于后续厌氧消化.通过对比研究发现,酸-碱预处理后,厌氧消化到第15 d,酸-碱预处理污泥的累积甲烷产量(CH4/VSS加入)达到136.1 mL·g-1,分别是空白对照、碱-酸预处理和单独碱预处理方式的2.5、 1.7和1.6倍,厌氧消化效率最高.经过8 d酸-碱预处理和15 d的厌氧消化,挥发性悬浮固体(VSS)总去除率达到60.9%,污泥减量效果比其他预处理要好.很显然,酸-碱预处理方式更有利于污泥厌氧消化及污泥减量化. |
| 英文摘要 |
| In order to enhance the efficiency of anaerobic digestion of excess sludge, acid-alkali pretreatment method was studied. Three different pretreatment methods (alkali alone,acid-alkali, alkali-acid) were compared to investigate their impacts on hydrolysis and acidification of activated sludge. In addition, their influences on methane-producing in subsequent anaerobic digestion process were also studied. The results showed that the soluble chemical oxygen demand (SCOD) of alkaline treatment alone was about 16% higher than the combining of acid and alkali treatment, SCOD concentration increased to 5406.1 mg·L-1 after 8 d pretreatment. After treated by acid (pH 4.0, 4 d) and alkali (pH 10.0, 4 d), the acetic acid production and its content in short-chain fatty acids (SCFAs) were higher than other pretreatment methods. And the acetic acid production (as COD/VSS) could reach 74.4 mg·g-1, accounting for 60.5% of SCFAs. After acid-alkali pretreatment, the C∶N ratio of the sludge mixed liquor was about 25, and the C∶P ratio was between 35-40, which was more favorable than C∶N and C∶P ratio of alkali alone and alkali-acid to subsequent anaerobic digestion. The control experiments showed that, after acid-alkali pretreatment, anaerobic digestion cumulative methane yield (CH4/VSSin) reached to 136.1 mL·g-1 at 15 d, which was about 2.5-, 1.6-, and 1.7-fold of the blank (unpretreated), alkali alone pretreatment and alkali-acid pretreatment, respectively. After acid-alkali pretreatment for 8 d and anaerobic digestion for 15 d, the removal efficiency of VSS was about 60.9%, and the sludge reduction effect was better than other pretreatments. It is obvious that the acid-alkali pretreatment method was more favorable to anaerobic digestion and sludge reduction. |
|
|
|
