共查询到19条相似文献,搜索用时 140 毫秒
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乙二醇是重要的基础有机化工产品和原料,具有石化、生物质和煤气化合成气3种制备路线,近年来煤气化合成气制乙二醇技术在我国快速发展。然而,煤制乙二醇废水主要来自气化、DMO合成等,具有有机物和硝酸盐含量高、有毒和难降解等特点,废水达标排放成为煤制乙二醇技术应用的主要约束条件之一。对煤制乙二醇废水处理的关键技术,包括煤气化废水脱氨、脱酚、破氰的萃取和汽提预处理技术、废水酯化脱硝酸技术、复合膜脱氮技术、有机物生化降解技术、高盐废水浓缩分盐结晶技术等进行了综述性评价,总结了各工艺的应用场景和特点。结果表明,预处理可去除油、酚、氨等有毒物质并降低悬浮物浓度,生化阶段可进一步降低COD、氨氮和有机物浓度,蒸发结晶可实现废水近零排放。预处理—生化—分盐结晶技术适用于合成气制乙二醇废水处理,加强源头污染控制、实行清洁生产、加强高盐废水近零排放技术研发是合成气制乙二醇废水处理未来的发展趋势,并从废水资源化角度提出研发建议。 相似文献
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针对煤气化过程形成的废水量大、成分复杂、污染物含量较高,且因煤种、气化工艺不同而成分变化,处理难度很大的特点,研究采用冷冻浓缩技术对Texaco和Lurgi法气化废水进行处理。结果表明,采用冷冻浓缩技术可以将气化废水中的有机物和无机物基本脱除,产水的COD不超过10 mg/L,COD和电导率符合HG/T 3923-2007循环冷却水用再生水水质标准,不易受进水中钙离子含量的影响。处理Texaco和Lurgi气化废水的产水率分别超过90%和95%,可显著提高废水回用率,并降低废水处理量。表明冷冻浓缩技术可作为气化废水处理的新选择。 相似文献
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煤加压气化废水由于成分复杂,对其无害化处理一直是关注焦点。文章通过分析目前主流的废水处理工艺,针对煤加压气化废水的特点,归纳了一级、二级和生化处理阶段不同的处理方法,对生产实践中的废水处理具有指导意义。 相似文献
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碎煤加压气化工艺以其工艺技术成熟、可靠,广泛应用于大型煤化工项目中,在运行中衍生的煤气化废水组分非常复杂,处理过程包括预分离、酚和氨的回收、生化处理等。从煤气化废水预处理角度阐述煤气化废水的组分,分析预分离中气-液、液-液、液-固3种分离过程,强调运行中值得关注的重要环节,掌控这些操作细节确保煤气化废水预分离顺利完成。 相似文献
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煤气化联合循环发电示范状况和煤气化工艺对比 总被引:1,自引:0,他引:1
煤炭气化已被确认为制取管道煤气或合成气的技术。经多方研究已被工业化规模生产和煤气化联合循环发电所证实。本文评述了煤的基本性质对气化效率的影响,煤气化联合循环发电示范厂现状和各种选定用于煤气化联合循环发电的第二代煤气化方法的对比。本文最后阐述了煤气化联合循环发电用于改造高能耗的以煤、油和天然气为燃料的中小规模电厂的现实性。 相似文献
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研究了褐煤作为吸附剂,处理煤化工气化废水。通过投加量、温度、时间等因素的试验,通过哈希DR3900分光光度计,研究褐煤吸附煤化工气化废水的总氮效果。当褐煤的用量达到400 g/L时,其对总氮的去除率可达到近60%。褐煤作为吸附剂去除废水总氮的方法可作为煤化工废水处理的预处理。 相似文献
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针对煤化工企业废水“零排放”的要求和污水回用的需求,通过分析典型煤气化工艺的废水水质特征,总结现代煤化工企业的废水处理、回用和“零排放”技术,介绍煤化工企业的废水处理技术应用案例,分析当前煤化工企业废水处理技术应用中存在的主要问题,并提出相关建议。 相似文献
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煤制气废水处理技术研究进展 总被引:1,自引:0,他引:1
介绍了煤制气废水的产生、水质特点,其治理难题表现在:水质复杂、难降解有机物含量高和毒性大。从煤制气废水治理技术的物化预处理、生物处理和深度处理三方面综述了国内外有关煤制气废水处理技术的研究现状、发展趋势及工程应用情况,并着重分析各处理技术的优缺点和在应用中存在的问题,即蒸氨和脱酚工艺的优化、发挥厌氧工艺的作用、废水生物脱氮过程的抑制、高级氧化和膜分离技术的应用。展望了煤制气废水处理技术的未来研究方向,指出物化和生物处理技术的优化组合是煤制气废水处理技术的必然发展趋势,为解决煤制气产业发展的废水治理瓶颈提供借鉴和参考。 相似文献
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Haijiao Lu Jingkang Wang Jun Yu Yuefeng Wu Ting Wang Ying Bao Dou Ma Hongxun Hao 《中国化学工程学报》2017,25(7):955-962
The pseudo-ternary system (NaCl + Na2SO4 + H2O) of coal gasification wastewater was studied at T =(268.15to 373.15) K.The solubility and density of the equilibrium liquid phase were determined by the isothermal solution saturation method.The equilibrium solids were also investigated by the Schreinemaker's method of wet residues and X-ray powder diffraction (XRD).According to the experimental data,the phase diagrams were determined.It was found that there was no significant solubility difference on the NaCl-rich side between the ternary system (NaCl + Na2SO4 + H2O) in coal gasification wastewater and in pure water.However,the solubility on the Na2SO4-rich side of coal gasification wastewater was apparently higher than that of pure water.The increase in the solubility of Na2SO4 was most likely caused by the effects of other impurities apart from NaCl and Na2SO4 in coal gasification wastewater.The measured data and phase equilibrium diagrams can provide fundamental basis for salt recovery in coal gasification wastewater. 相似文献
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Hiroyuki Nakagawa 《Fuel》2004,83(6):719-725
Brown coals will continue to be important energy resources in the near future, but their high water contents, which sometimes exceed 50 wt%, and their low calorific values restrict their utilization. Development of an efficient treatment method for dewatering and upgrading is desired to utilize brown coals on a large scale. Hydrothermal treatment is believed to be a promising treatment method because it can not only remove water in liquid phase but also improve calorific value of brown coal. However, some organic compounds are inevitably leached out from the coal during the treatment to emit a huge amount of wastewater containing organic compounds in small concentration, which causes a loss of coal energy as well as a serious problem of wastewater treatment. In this paper, an Australian brown coal (Morwell) was hydrothermally treated for dewatering and upgrading at 250-300 °C. When treated at 300 °C, the water content decreased from 1.31 kg/kg on dry matter to 0.59 kg/kg on dry matter and the calorific value increased from 25.8 to 27.8 MJ/kg on dry matter, indicating that the hydrothermal treatment is really effective for dewatering and upgrading the brown coal. The reactivity to oxygen at low temperature was also reduced by the treatment, which will contribute to suppress the spontaneous combustion of the coal. On the other hand, the amount of organic compound dissolved in the recovered wastewater increased with increasing treatment temperature and it reached ca. 1.5% on carbon basis at 300 °C. The wastewater was treated using a novel Ni-supported carbon catalyst developed by the authors. The organic compounds in the wastewater were completely gasified at as low as 350 °C under 20 MPa at the liquid hourly space velocity of as large as 50, producing combustible gas rich in CH4 and H2. The proposed hydrothermal gasification process was found not only to be efficient for wastewater treatment but also to be effective for energy recovery from wastewater. The gasification process combined with the hydrothermal treatment process, which is operated under the conditions close to those of the gasification, will be a new and effective brown coal pretreatment process. 相似文献