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期刊论文 7

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地基沉降 1

悬索桥 1

拼装 1

桥梁施工 1

沉井 1

深井降水 1

空气吸泥 1

锚碇 1

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An integrated method for the rapid dewatering and solidification/stabilization of dredged contaminated

Hefu Pu, Aamir Khan Mastoi, Xunlong Chen, Dingbao Song, Jinwei Qiu, Peng Yang

《环境科学与工程前沿(英文)》 2021年 第15卷 第4期 doi: 10.1007/s11783-020-1359-1

摘要: Abstract • An integrated method, called PHDVPSS, was proposed for treating DCS. • The PHDVPSS method showed superior performance compared to conventional method. • Using the method, water content (%) of DCS decreased from 300 to<150 in 3 days. • The 56-day UCS from this method is 12‒17 times higher than conventional method. • Relative to PC, GGBS-MgO binder yielded greater reduction in the leachability. To more efficiently treat the dredged contaminated sediment (DCS) with a high water content, this study proposes an integrated method (called PHDVPSS) that uses the solidifying/stabilizing (S/S) agents and prefabricated horizontal drain (PHD) assisted by vacuum pressure (VP). Using this method, dewatering and solidification/stabilization can be carried out simultaneously such that the treatment time can be significantly shortened and the treatment efficacy can be significantly improved. A series of model tests was conducted to investigate the effectiveness of the proposed method. Experimental results indicated that the proposed PHDVPSS method showed superior performance compared to the conventional S/S method that uses Portland cement (PC) directly without prior dewatering. The 56-day unconfined compressive strength of DCS treated by the proposed method with GGBS-MgO as the binder is 12‒17 times higher than that by the conventional S/S method. DCS treated by the PHDVPSS method exhibited continuous decrease in leaching concentration of Zn with increasing curing age. The reduction of Zn leachability is more obvious when using GGBS-MgO as the binder than when using PC, because GGBS-MgO increased the residual fraction and decreased the acid soluble fraction of Zn. The microstructure analysis reveals the formation of hydrotalcite in GGBS-MgO binder, which resulted in higher mechanical strength and higher Zn stabilization efficiency.

关键词: Dredged contaminated sediment     Dewatering     Solidification/stabilization     Vacuum preloading     Prefabricated horizontal drain     Heavy metal    

Possible solutions for sludge dewatering in China

Wei WANG, Yuxiang LUO, Wei QIAO,

《环境科学与工程前沿(英文)》 2010年 第4卷 第1期   页码 102-107 doi: 10.1007/s11783-010-0001-z

摘要: In China, over 1.43×10 tons of dewatered sewage sludge, with 80% water content, were generated from wastewater treatment plants in 2007. About 60% of the COD removed during the wastewater treatment process becomes concentrated as sludge. Traditional disposal methods used by municipal solid waste treatment facilities, such as landfills, composting, or incineration, are unsuitable for sludge disposal because of its high water content. Disposal of sludge has therefore become a major focus of current environmental protection policies. The present status of sludge treatment and disposal methodology is introduced in this paper. Decreasing the energy consumption of sludge dewatering from 80% to 50% has been a key issue for safe and economic sludge disposal. In an analysis of sludge water distribution, thermal drying and hydrothermal conditioning processes are compared. Although thermal drying could result in an almost dry sludge, the energy consumption needed for this process is extremely high. In comparison, hydrothermal technology could achieve dewatered sewage sludge with a 50%–60% water content, which is suitable for composting, incineration, or landfill. The energy consumption of hydrothermal technology is lower than that required for thermal drying.

关键词: sewage sludge disposal     water content     thermal drying     hydrothermal conditioning    

Recovering humic substances from the dewatering effluent of thermally treated sludge and its performance

Yuning YANG,Huan LI

《环境科学与工程前沿(英文)》 2016年 第10卷 第3期   页码 578-584 doi: 10.1007/s11783-015-0827-5

摘要: The biologic treatment of the dewatering effluent from thermally treated sludge is difficult due to the high concentration of refractory humic substances. On the other hand, humic substances are an important source of organic fertilizer. In this study, a novel process using ferric coagulant was developed to recover humic substances from dewatering effluent for use as an organic fertilizer. When ferric coagulant was applied to raw dewatering effluent, up to 70% of humic substances were enmeshed by hydrolyzed ferric ions at an optimum pH of 4.5. The proper mass ratio of iron ions to humic substances was 0.6. In the recovered material, humic substances accounted for 24.2% of the total dry solids, and the amount of phosphorus (equivalent phosphorus pentoxide) was 6.2%. Heavy metals and other components all met the legal requirements for organic fertilizer. When the recovered material was applied to soybeans, the germination and growth of the seeds was significantly improved.

关键词: sewage sludge     humic substances     recovery     phosphorus     fertilizer    

Enhanced dewatering characteristics of waste activated sludge with Fenton pretreatment: effectiveness

Guangyin ZHEN, Xueqin LU, Baoying WANG, Youcai ZHAO, Xiaoli CHAI, Dongjie NIU, Tiantao ZHAO

《环境科学与工程前沿(英文)》 2014年 第8卷 第2期   页码 267-276 doi: 10.1007/s11783-013-0530-3

摘要: In this work, the enhanced dewaterabing characteristics of waste activated sludge using Fenton pretreatment was investigated in terms of effectiveness and statistical optimization. Response surface method (RSM) and central composite design (CCD) were applied to evaluate and optimize the effectiveness of important operational parameters, i.e., H O concentrations, Fe concentrations and initial pH values. A significant quadratic polynomial model was obtained ( 0.9189) with capillary suction time (CST) reduction efficiency as the response. Numerical optimization based on desirability function was carried out. The optimum values for H O , Fe , and initial pH were found to be 178 mg·g VSS (volatile suspended solids), 211 mg·g VSS and 3.8, respectively, at which CST reduction efficiency of 98.25% could be achieved. This complied well with those predicted by the established polynomial model. The results indicate that Fenton pretreatment is an effective technique for advanced waste activated sludge dewatering. The enhancement of sludge dewaterability by Fenton’s reagent lies in the migration of sludge bound water due to the disintegration of sludge flocs and microbial cells lysis.

关键词: Fenton pretreatment     response surface methodology (RSM)     capillary suction time (CST)     dewaterabilty     molecular weight distribution    

A full-scale integrated-bioreactor with two zones treating odours from sludge thickening tank and dewatering

Jianwei Liu, Kaixiong Yang, Lin Li, Jingying Zhang

《环境科学与工程前沿(英文)》 2017年 第11卷 第4期 doi: 10.1007/s11783-017-0932-8

摘要: A full-scale integrated-bioreactor consisting of a suspended zone and an immobilized zone was employed to treat the ordours emitted from a wastewater treatment plant. The inlet concentrations of H S and NH were 1.6–38.6 mg·m and 0.1–6.7 mg·m , respectively, while the steady-state outlet concentrations were reduced to 0–2.8 mg·m for H S and 0–0.5 mg·m for NH . Both H S and NH were eliminated effectively by the integrated bioreactor. The removal efficiencies of H S and NH differed between the two zones. Four species of microorganisms related to the degradation of H S and NH were isolated. The characteristics and distributions of the microbes in the bioreactor depended on the inlet concentration of substrates and the micro-environmental conditions in the individual zones. Product analysis indicated that most of the H S was oxidized into sulfate in the immobilized zone but was dissolved into the liquid phase in the suspended zone. A large amount of NH was converted into nitrate and nitrite by nitration in the suspended zone, whereas only a small amount of NH was transferred to the aqueous phase mainly by absorption or chemical neutralization in the immobilized zone. Different microbial populations dominated the individual zones, and the major biodegradation products varied accordingly.

关键词: Biological deodorization     Microbial characteristics     Ammonia     Hydrogen sulfide     Wastewater treatment plant    

Dewatering of Scenedesmus Obliquus Cultivation Substrate with Microfiltration: Potential and Challenges

Marco Malaguti,Lorenzo Craveri,Francesco Ricceri,Vincenzo Riggio,Mariachiara Zanetti,Alberto Tiraferri,

《工程(英文)》 doi: 10.1016/j.eng.2023.07.010

摘要: In the microalgae harvesting process, which includes a step for dewatering the algal suspension, directly reusing extracted water in situ would decrease the freshwater footprint of cultivation systems. Among various algae harvesting techniques, membrane-based filtration has shown numerous advantages. This study evaluated the reuse of permeate streams derived from Scenedesmus obliquus (S. obliquus) biomass filtration under bench-scale and pilot-scale conditions. In particular, this study identified a series of challenges and mechanisms that influence the water reuse potential and the robustness of the membrane harvesting system. In a preliminary phase of this investigation, the health status of the initial biomass was found to have important implications for the harvesting performance and quality of the permeate stream to be reused; healthy biomass ensured better dewatering performance (i.e., higher water fluxes) and higher quality of the permeate water streams. A series of bench-scale filtration experiments with different combinations of cross-flow velocity and pressure values were performed to identify the operative conditions that would minimize energy requirements while maximizing water productivity. The optimal conditions, 2.2 m·s−1 and 1.4 bar (1 bar = 105 Pa), respectively, were then applied to drive pilot-scale microfiltration tests to reuse the collected permeate as a new cultivation medium for S. obliquus growth in a pilot-scale photo-bioreactor. The investigation revealed key differences between the behavior of the membrane systems at the two scales (bench and pilot). It indicated the potential for beneficial reuse of the permeate stream as the pilot-scale experiments ensured high harvesting performance and growth rates of biomass in permeate water that were highly similar to those recorded in the ideal cultivation medium. Finally, different nutrient reintegration protocols were investigated, revealing that both macro- and micronutrient levels are critical for the success of the reuse approach.

关键词: Scenedesmus obliquus     Microfiltration     Permeate reuse     Harvesting     Microalgae     Pilot-scale    

陆上特大型沉井施工技术

邱琼海,林帆,姜江华

《中国工程科学》 2010年 第12卷 第4期   页码 14-20

摘要:

泰州大桥主桥采用主跨2×1 080 m三塔两跨两锚碇悬索桥,其中南、北锚碇基础为特大型沉井,矩形平面尺寸为67.9 m×52.0 m,高度分别为41 m,57 m。针对锚碇基础覆盖层深厚、基础尺寸巨大、沉井下沉深度深等特点,通过施工技术的攻关,顺利完成了砂桩复合地基处理、沉井制作和拼装、钢壳沉井混凝土填充、混凝土沉井接高施工、水力机械冲吸式排水下沉和空气吸泥机吸泥下沉等多项施工工序,为今后陆上特大型沉井施工提供了借鉴。文章简要介绍了南、北锚碇陆上特大型沉井的施工技术。

关键词: 悬索桥     锚碇     沉井     拼装     深井降水     地基沉降     空气吸泥     桥梁施工    

标题 作者 时间 类型 操作

An integrated method for the rapid dewatering and solidification/stabilization of dredged contaminated

Hefu Pu, Aamir Khan Mastoi, Xunlong Chen, Dingbao Song, Jinwei Qiu, Peng Yang

期刊论文

Possible solutions for sludge dewatering in China

Wei WANG, Yuxiang LUO, Wei QIAO,

期刊论文

Recovering humic substances from the dewatering effluent of thermally treated sludge and its performance

Yuning YANG,Huan LI

期刊论文

Enhanced dewatering characteristics of waste activated sludge with Fenton pretreatment: effectiveness

Guangyin ZHEN, Xueqin LU, Baoying WANG, Youcai ZHAO, Xiaoli CHAI, Dongjie NIU, Tiantao ZHAO

期刊论文

A full-scale integrated-bioreactor with two zones treating odours from sludge thickening tank and dewatering

Jianwei Liu, Kaixiong Yang, Lin Li, Jingying Zhang

期刊论文

Dewatering of Scenedesmus Obliquus Cultivation Substrate with Microfiltration: Potential and Challenges

Marco Malaguti,Lorenzo Craveri,Francesco Ricceri,Vincenzo Riggio,Mariachiara Zanetti,Alberto Tiraferri,

期刊论文

陆上特大型沉井施工技术

邱琼海,林帆,姜江华

期刊论文