摘要
以超低泥龄活性污泥工艺产生的剩余污泥为研究对象,通过高温化学活化的方法将其制备成不同的污泥基吸附剂(sludge-based adsorbents,SBAs),并表征了SBAs的物理化学性质,针对现有工艺出水有机物较高的问题,以有机物(TCOD)去除率为评价指标,优选出性能良好的2种污泥基吸附剂(SBA1、SBA5),并将其与2种混凝剂(Fe_2(SO_4)_3和Al_2(SO_4)_3)耦合使用进一步去除水中有机物。研究结果表明:制备污泥基吸附剂的孔隙结构得到了很大改善,SBA5的有机物去除效率优于SBA1。联用试验中,SBA5与Fe_2(SO_4)_3联用的TCOD去除率达到最高为48%。相比于混凝剂对溶解态COD的去除率,联用试验的去除率从25. 5%～34. 7%提升到49. 3%～60. 1%,实现污泥资源化的同时提高了有机物的去除率。
The excess sludge produced by the ultra-short sludge retention time activated sludge process was studied,and prepared into different sludge-based adsorbents( SBAs) by chemical activation at high-temperature. The physical and chemical properties of SBAs were characterized. In response to the problem of high organic matter of effluent in the process,TCOD removal rate was used as an index. Two sludge-based sorbents( SBA1 and SBA5) with good performance were preferably used in combination with two coagulants( Fe_2( SO_4)_3 and Al_2( SO_4)_3) to further remove organic matter of the effluent. The results showed that the pore structure of the prepared sludge-based adsorbent was greatly improved,and the TCOD removal rate of SBA5 was better than SBA1. In the combined experiment,the TCOD removal rate of the combination of SBA5 and Fe_2( SO_4)_3 reached the maximum value of 48%. Compared to the soluble COD removal rate of the coagulant,the removal rate of the combined experiments was increased from 25. 5% ～ 34. 7% to 49. 3% ～ 60. 1%. Excess sludge was recycled and the removal efficiency of organic matter was improved at the same time.
引文
[1] Valverde-Pérez B,Wágner D S,Lóránt B,et al. Short-sludge age EBPR process-Microbial and biochemical process characterisation during reactor start-up and operation[J]. Water Research,2016,104:320-329.
[2] Ge H, Batstone D J,Keller J. Operating aerobic wastewater treatment at very short sludge ages enables treatment and energy recovery through anaerobic sludge digestion[J]. Water Research,2013,47(17):6546-6557.
[3] Kante K,Qiu J,Zhao Z,et al. Development of surface porosity and catalytic activity in metal sludge/waste oil derived adsorbents:effect of heat treatment[J]. Chemical Engineering Journal,2008,138(1):155-165.
[4] Ding R,Zhang P F,Seredych M,et al. Removal of antibiotics from water using sewage sludge-and waste oil sludge-derived adsorbents[J]. Water Research,2012,46(13):4081-4090.
[5] Trzcinski A P,Ganda L,Yan N A,et al. Identification of recalcitrant compounds in a pilot-scale AB system:an adsorption(A)stage followed by a biological(B)stage to treat municipal wastewater[J]. Bioresource Technology,2016,206:121-127.
[6] Zhang Y K,Liu X H,Liu X W,et al. Research advances in deriving renewable energy from biomass in wastewater treatment plants[J]. RSC Advances,2016,6(61):55903-55918.
[7] Hadi P,Xu M,Ning C,et al. A critical review on preparation,characterization and utilization of sludge-derived activated carbons for wastewater treatment[J]. Chemical Engineering Journal,2015,260(260):895-906.
[8] Xu G, Xin Y, Spinosa L. Development of sludge-based adsorbents:preparation, characterization, utilization and its feasibility assessment[J]. Journal of Environmental Management,2015,151:221-232.
[9] Gergova K,Eser S. Effects of activation method on the pore structure of activated carbons from apricot stones[J]. Carbon,1996,34(7):879-888.
[10] Lillo-Ródenas M A,Ros A,Fuente E,et al. Further insights into the activation process of sewage sludge-based precursors by alkaline hydroxides[J]. Chemical Engineering Journal,2008,142(2):168-174.
[11] Monsalvo V M,Mohedano A F,Rodriguez J J. Activated carbons from sewage sludge:application to aqueous-phase adsorption of 4-chlorophenol[J]. Desalination,2011,277(1):377-382.
[12] Xu G, Xin Y, Spinosa L. Development of sludge-based adsorbents:preparation, characterization, utilization and its feasibility assessment[J]. Journal of Environmental Management,2015,151:221-232.
[13] Jimenez J,Miller M,Bott C,et al. High-rate activated sludge system for carbon management-Evaluation of crucial process mechanisms and design parameters[J]. Water research,2015,87:476-482.
[14] Kucharska M,Naumczyk J. Degradation of selected chlorophenols by advanced oxidation processes[J]. Environment Protection Engineering,2009,35(2):47-55.
[15] Hwang H R,Choi W J,Kim T J,et al. The preparation of an adsorbent from mixtures of sewage sludge and coal-tar pitch using an alkaline hydroxide activation agent[J]. Journal of Analytical and Applied Pyrolysis,2008,83(2):220-226.
[16] Lu G Q,Low J C F,Liu C Y,et al. Surface area development of sewage sludge during pyrolysis[J]. Fuel,1995,74(3):344-348.
[17] Lin Q H,Cheng H,Chen G Y. Preparation and characterization of carbonaceous adsorbents from sewage sludge using a pilot-scale microwave heating equipment[J]. Journal of Analytical&Applied Pyrolysis,2012,92(1):113-119.
