利用污泥制备活性炭是具有广泛应用前景的污泥资源化利用途径。但是目前对污泥基活性炭(SDAC)制备工艺进行评价的研究较少。以污水厂污泥制备活性炭为对象,建立了制备工艺流程图,运用生命周期评价(LCA),定量揭示制备工艺的环境影响及关...利用污泥制备活性炭是具有广泛应用前景的污泥资源化利用途径。但是目前对污泥基活性炭(SDAC)制备工艺进行评价的研究较少。以污水厂污泥制备活性炭为对象,建立了制备工艺流程图,运用生命周期评价(LCA),定量揭示制备工艺的环境影响及关键影响因素。结果表明,整个制备工艺中焙烧步骤对环境的影响占主导地位,其次是研磨或浸渍步骤,最后是洗涤和干燥步骤。水蒸气物理活化、CO_(2)物理活化、KOH浸渍法、ZnCl_(2)浸渍法、H_(3)PO_(4)浸渍法、ZnCl_(2)熔融盐法、物理化学法的能量消耗量分别为68.976,79.776,47.376,53.964,48.564,45.828,46.764 MJ/kg活性炭,而全球变暖潜力值分别为14.93,17.06,15.54,13.42,14.51,12.65,13.91 kg CO_(2)eq/kg活性炭。LCA结果表明,利用CO_(2)物理活化方法制备活性炭对环境影响最大,而ZnCl_(2)熔融盐法对环境影响最小。对ZnCl_(2)熔融盐法敏感性分析结果表明,用电量和活化剂是进一步优化活性炭制备方法的两个关键因素。基于生命周期视角,ZnCl_(2)熔融盐法制备SDAC效果更优,同时应强化设备节能改造,可显著降低SDAC制备过程环境影响。展开更多
Sewage sludge with the additive corn cob was used as prescusor to prepare sludge-based carbon adsorbents by pyrolysis method. And then, the carbonizated products were activated with potassium hydroxide. The mixing rat...Sewage sludge with the additive corn cob was used as prescusor to prepare sludge-based carbon adsorbents by pyrolysis method. And then, the carbonizated products were activated with potassium hydroxide. The mixing ratio of the corn cob to sewage sludge was investigated. The surface area and pore size distribution, elemental composition, surface chemistry structure and the surface physical morphology were determined and compared. The results demonstrated that the addition of corn cob into the sewage sludge sample could effectively improve the surface area （from 287 to 591 m 2 /g） and the microporosity （from 5% to 48%） of the carbon based adsorbent, thus enhancing the adsorption behavior. The sulfur dioxide adsorption capacity was measured according to breakthrough test. It was found that the sulfur dioxide adsorption capacity of the adsorbents was obviously enhanced after the addition of the corn cob. It is presumed that not only highly porous adsorbents, but also a high metallic content of these materials are required to achieve good performances.展开更多
文摘利用污泥制备活性炭是具有广泛应用前景的污泥资源化利用途径。但是目前对污泥基活性炭(SDAC)制备工艺进行评价的研究较少。以污水厂污泥制备活性炭为对象,建立了制备工艺流程图,运用生命周期评价(LCA),定量揭示制备工艺的环境影响及关键影响因素。结果表明,整个制备工艺中焙烧步骤对环境的影响占主导地位,其次是研磨或浸渍步骤,最后是洗涤和干燥步骤。水蒸气物理活化、CO_(2)物理活化、KOH浸渍法、ZnCl_(2)浸渍法、H_(3)PO_(4)浸渍法、ZnCl_(2)熔融盐法、物理化学法的能量消耗量分别为68.976,79.776,47.376,53.964,48.564,45.828,46.764 MJ/kg活性炭,而全球变暖潜力值分别为14.93,17.06,15.54,13.42,14.51,12.65,13.91 kg CO_(2)eq/kg活性炭。LCA结果表明,利用CO_(2)物理活化方法制备活性炭对环境影响最大,而ZnCl_(2)熔融盐法对环境影响最小。对ZnCl_(2)熔融盐法敏感性分析结果表明,用电量和活化剂是进一步优化活性炭制备方法的两个关键因素。基于生命周期视角,ZnCl_(2)熔融盐法制备SDAC效果更优,同时应强化设备节能改造,可显著降低SDAC制备过程环境影响。
基金supported by the National Hi-Tech Research and Development Program (973) of China (No.2011CB201505, 2010CB732206)the National Natural Science Foundation of China (No.20907008)+1 种基金the Specialized Research Fund for the Doctoral Program of Higher Education (No.20090092120010)support of the Foundation for Southeast University Excellent Young Teacher
文摘Sewage sludge with the additive corn cob was used as prescusor to prepare sludge-based carbon adsorbents by pyrolysis method. And then, the carbonizated products were activated with potassium hydroxide. The mixing ratio of the corn cob to sewage sludge was investigated. The surface area and pore size distribution, elemental composition, surface chemistry structure and the surface physical morphology were determined and compared. The results demonstrated that the addition of corn cob into the sewage sludge sample could effectively improve the surface area （from 287 to 591 m 2 /g） and the microporosity （from 5% to 48%） of the carbon based adsorbent, thus enhancing the adsorption behavior. The sulfur dioxide adsorption capacity was measured according to breakthrough test. It was found that the sulfur dioxide adsorption capacity of the adsorbents was obviously enhanced after the addition of the corn cob. It is presumed that not only highly porous adsorbents, but also a high metallic content of these materials are required to achieve good performances.
