用鼓风炉渣消除铬渣毒性的研究.pdf

用鼓风炉渣消除铬渣毒性的研究 ＊ 王明玉 东北大学材料与冶金学院, 沈阳 110004 李辽沙 安徽工业大学安徽省冶金与资源综合利用重点实验室, 马鞍山 243002 张 力 张林楠 隋智通 涂赣峰 东北大学材料与冶金学院, 沈阳 110004 摘要 针对含铬废渣对环境污染大及治理难的特点, 提出了以废渣治理废渣的技术, 利用鼓风炉渣的还原性以及刚排 出时的高温, 将铬渣按一定比例与之混合, 进行铬渣的解毒处理, 并对铬渣的解毒机理进行了理论分析。 从实验结果 可以看出, 当铬渣加入量低于 10时, 该技术能够较彻底的将铬渣中的Cr6 进行解毒。 关键词 铬渣 鼓风炉渣 解毒机理 ＊国家自然科学基金重点项目 50234040 1 引言 含铬废渣是铬盐生产厂或铬铁合金厂在生产过 程中排放出的一种有害废渣, 铬渣内含有水溶性和酸 溶性的 Cr 6是强致癌物质, 是造成环境污染的主要 原因 。据调查, 全国目前已经积存了近 250 万 t 的有 毒铬渣 ,而且每年还将以数十万吨的速度递增 [ 1～ 3] 。 针对我国铬渣产量大、处理成本高的特点 ,本研究采 用了以废渣治废渣的处理技术, 旨在降低处理成本, 增大用渣量,为铬渣的无毒化处理研究出一种新的处 理方法。 2 实验 实验原理 鼓风炉渣是在冰铜冶炼过程中生成的 还原性废渣,熔渣的氧化学位较低 ,有较强的还原性, 利用这一特点和刚排出时的高温, 将铬渣按一定比例 与之混合 ,使铬渣中的 Cr 6转变为 Cr3 ,并凝固在渣 中,从而达到铬渣解毒的目的 。 实验过程 将经过破碎、筛分的铬渣按一定比例 加入到刚出炉的鼓风炉渣中 , 混均冷却得到终渣 这 里把鼓风炉渣和铬渣反应后的生成渣称为终渣 , 然 后按标准方法 GB5086 -85有色冶金工业固体废物浸 出毒性试验方法标准 进行毒性去除实验,其流程见 图1 。实验所用鼓风炉渣和铬渣的主要化学成分示 于表 1 和表 2。 图 1 铬渣解毒处理流程图 表 1 鼓风炉渣的主要化学成分 质量百分比 化学组成CaOMgOSiO2Al2O3FeOSCu其它 鼓风炉渣9. 53. 037. 37. 538. 50. 90. 52. 8 表 2 铬渣的主要化学成分 质量百分比 化学组成CaOMgO SiO2Al2O3Fe2O3Na2CrO4Cr2O3其它 铬 渣28. 032. 08. 512. 012. 01. 55. 01. 0 3 实验结果与讨论 3. 1 实验结果 实验利用的是鼓风炉渣的高温及还原性 ,所以铬 渣的加入量会对其解毒效果产生影响,见图 2。 图 2 铬渣加入量与 Cr6 浸出量的关系 图中曲线 Ⅰ表示的是终渣中 Cr 6的浸出量 浸 出时间为 90 d 与铬渣加入量 铬渣量与终渣总量之 比 的关系 曲线 Ⅱ是反应前 Cr 6在总渣量中所占的 比例 认为 Cr 6是完全浸出的 。从图中可以看出, 该技术能够使铬渣解毒; 随铬渣加入量的增大浸出液 中Cr 6含量变大 ,当铬渣加入量 12时, 终渣浸出 液中 Cr 6含量显著增加 , 这是因为本技术利用的是 鼓风炉渣刚排出时自身所具有的热量,当铬渣加入量 65 环 境 工 程 2005年 8 月第23 卷第4 期 达到一定比例后 ,鼓风炉渣自身的热量将不足以使加 入的铬渣熔融, 从而会使解毒效果明显下降。当铬渣 加入量 10时, 浸出液中 Cr 6含量 120 L m 3 后 , 液气比对 HCl 脱除 率影响 不大 。 图 4 液气比与 SO2脱除率 R 的关系 3. 2. 3 吸收液中HCl 的含量对 R 的影响 在 HCl 入 口 浓 度 为 3. 9 10 -3 , 液 气 比 为 100 L m 3条件下 , 控制入口气速为10 m s和操作温度 为25 ℃,考察了吸收液中 HCl 的含量与 HCl 脱除率 R 之间的关系 。试验结果见图 5。由试验结果可以 看出, 当吸收液中 HCl 的含量较小时 ,HCl 脱除率较 高。这种关系符合气体吸收的一般原理。当吸收液 中HCl 的浓度增大到 8 时 ,HCl 脱除率开始显著下 降。为保证较高的HCl 脱除率 ,吸收液中HCl 的浓度 应控制在 8 以内。 3. 2. 4 操作条件对粉尘去除率 R1的影响 操作温度 、 吸收液的组成对粉尘去除率R1无影 图 5 吸收液中HCl 的含量与 HCl 脱除率 R 的关系 响 。液气比大于50 L m 3后 ,对 R 1的影响变得十分微 弱。在正常操作条件下, 排出气体中检测不出夹带 碳黑 。 4 结论 用水作为循环吸收液 ,涡旋脉冲反应器能高效率 地脱除废气中的 HCl 和粉尘。适宜的工艺条件为 操 作温度低于20 ℃; 液气比 60～ 80 L m 3 ; 吸收液中 HCl 的含量不大于 8。在适宜的工艺条件下,HCl 脱除 率可达 99. 5 以上, 粉尘去除率接近 100。系统操 作弹性很大, 当超过120 L m 3后 , 液气比几乎对脱除 率没有影响 。这一特性特别适于气体流量波动大的 废气处理操作。 参考文献 1 刘晓涛, 郭卫兵等. 穿流板塔治理HCl 废气工艺探讨. 环境工程, 1999. 17 5 33～ 35. 2 Mallinson. R, Ramshaw . C. [ P] . US4263255, 1981. 3 诸永泉, 谈定生等. 废气中低浓度氯化氢制取盐酸的研究及应用. 上海化工, 1999. 24 8 13～ 16. 作者通讯处 罗鹏 110142 沈阳经济技术开发区 11 号街 沈阳化 工学院 电话 024 89383281 2004- 12-07 收稿 上接第 66页 入最大量低于 10时 ,终渣中浸出毒性六价铬浓度 低于国家标准的 1. 5 mg L ,达到环境排放要求; 2 解毒方法以废治废, 方法简单 , 成本低易于 实现 。 参考文献 1 兰嗣国, 殷惠民, 狄一安等. 浅谈铬渣解毒技术. 环境科学研究, 1998. 11 3 53～ 56. 2 韩怀芬, 黄玉柱, 金漫彤. 铬渣的固化 稳定化研究. 环境污染与防 治,2002. 24 4 199～ 200. 3 孙春宝, 孙加林. 含铬废渣的综合利用途径研究. 环境工程, 1997. 15 1 42～ 44. 4 东北大学无机化学教研室编. 大学化学 Ⅱ . 沈阳 东北大学出版 社, 1993. 155. 5 刘锦华, 刘英杰, 张惠棠. 铬渣烧结中铬酸离子的还原和再氧化. 钢 铁研究学报 增刊 , 1997. 9 68～ 70. 6 李文超主编. 冶金热力学. 北京 冶金工业出版社, 1995. 37. 7 郭顺勤主编. 铬锰的性质及其应用. 北京 高等教育出版社,1992. 28. 8 方荣利, 金成昌. 铬渣的利用研究. 矿产综合利用, 1997. 5 50～ 44. 作者通讯处 王明玉 110004 东北大学材冶学院 119 2005- 01-04 收稿 46 环 境 工 程 2005年 8 月第23 卷第4 期 Keywords activated carbon, adsorption, PH3 EXPERIMENTAL STUDY ON PURIFYING DUST-BEARING WASTE GAS BY VORTEX LIQUID - GAS REACTORLuo Peng et al 44 Abstract A design of a novel vortex liquid -gas reactor was presented. Experimental studies were carried out in lab. The effects of temperature, the ratio of liquid gas and the concentration of HCl in the solution on HCl adsorptivity R were investigated. The experimental results showed that the vortex liquid -gas reactor can be used for removing the solid particles and hydrogen chloride gas in the carrier gas stream efficiently. It was also found that in the suitable conditions the HCl absorptivity could be as high as 99. 5 and there were no solids found in the discharged gas stream. Keywords reactor, waste gases treatment and hydrogen chloride EXPERIMENT RESEARCH ON TREATMENT OF ALDEHYDE POLLUTION BY TEA Wang Jinquan et al 47 Abstract In order to reduce the volatilisation content of aldehyde in the material of furniture, it is a experiment research that three plywood boardswere dealt separately with the extraction by liquid of teas and its mixed liquid with other reagents. The research results indicated that the extraction by liquid of teas could reduce the volatilisation conent of aldehyde from 400. 4μ g to 315. 4μ g, relative decrease about 21. 2; itsmixed liquidwith other reagents could reduce the volatilisation contnet of aldehyde from 390. 1μ g to 94. 6μ g, relative decrease about 75. 7. Keywords air pollution, tea, aldehyde and treatment RESEARCH ON MECHANISM OF SEVERAL SEMI-DRY DESULPHURIZATION PROCESSES GeJielong et al 49 Abstract In order to contrast and research the mechanism and perance of the desulphurization processes such as recycle semic -dry process, gas duct fluidized bed, lime spray in boiler and humidification activation behind boiler, semi -dry sprayer etc it is synthetically contrasted and analysed the inds of the desulphurization processes including react time, operating temperature. Ca S value, reliability, fuel applicability, equipmentfloor area, perance price ratio and so on. The result shows that novel integrated desulphurization technology NIDhas predominance on the inds such as fuel applicability, operating remperature, perance price ratio, operating reliability and so on by contrasting with other semi-dry desulphurization processes. So NID is well worth to be expanded and applied. Keywords semi -dry process, desulphurization, mechanism, inds and research THE FUNDAMENTAL STUDY ON THE REUTILIZATIONOF ELECTRONIC SCRAP BY PASSIVE PULSE AIR CLASSIFIERSDuan Chenlong et al 53 Abstract The mechanical separation of electronic scrapESwill benefit both the environment and the society. According to the characteristicsof ES, a passive pulse air -classifier was used to recover valuable components from ES at laboratory stage. The results of the laboratory experiments indicate that the passive pulsing classifiers achieve more effective results of separation and get a wider range of operating velocities of the airflow than the traditional ones. Keywords electronic scrap, mechanical separation, air -classifier, pulse air and separation efficiency CHARACTERISTICS OF BY -PRODUCTS FROM MUNICIPAL SOLID WASTE INCINERATOR He Pinjing et al 56 Abstract Incineration has become one of the major municipal solidwaste MSWtreatment processes in some cities of China. As a result, secondary pollution of by -products from the MSW incinerator is of increasing concern. According to the monitoring results over more than 2 years covering various seasons, the generation and typical characteristics of the leachate from the waste pit and the MSWI residues air pollution control residues and bottom ashare presented, taking a typicalMSW incinerator inShanghai as a case. Thereby the distribution of th heavy metals in the MSW incineration plant is discussed. Keywords municipal solid waste incineration, leachate, fly ash, bottom ash and properties of pollutants generation source RESEARCH STATUS AND PROBLEMS OF MODERN MUNICIPAL SOLID WASTE LANDFILL Li Zhibin et al 60 Abstract Modern municipal solid waste landfill isa most effective and safe in delaing withmunicipalwaste. A great deal of research work has been done by home and overseas scholars on geotechnical problems of landfill, but there are still some problems that have not been paid enough attention to. Based on the research achievements by home and overseas scholars, a series of problems were advanced that needed to be deeply researched. And some precautionary suggestions were given after tentative work. Keywords municipal solid waste landfill, geotechnical engineering problems and research status STUDY ONTOXICITY ELIMINATION OF CHROMIUM DREGS BY BLAST FURNACE SLAG Wang Mingyu et al 65 4 ENVIRONMENTAL ENGINEERING Vol. 23,No. 4, Aug . , 2005 Abstract A technique using the waste slag to treat chromium dregs has been advanced in order to eliminate environmental pollution. Using the high temperature and reduction of the blast furnace slag, the chromium dregs were mixed at appropriate proportion with blast furnace slag, which could make chromium dregs detoxify. In the present study, the detoxification mechanism of chromium dregs was analyzed theoretically. The experiment results show that the blast furnace slag can remove the toxic of Cr6completely while the mass quantity of added chromium dregs was less than 10 percent. Keywords chromium dregs, blast furnace slag and detoxification mechanism DISCUSSION ON PRODUCTION OF SOLID FUEL USING INDUSTRIAL SOLID WASTES WITH HEAT VALUELin Guangqing et al 67 Abstract A large amount of solidwastes are produced every year by industrial enterprises. If the wasteswith heat value are used to research and produce mixed RDF solid fuel, the advantages of recycling resources and recovering energy can be realized. It can control effectively the secondary pollution while the reduction of environmental pollution can also be realized, whose economic, social and environmental benefits have strong attraction, which is worth exploring . Keywords waste plastic film, sludge, RDF and solid fuel INFLUENCE OF LANDFILL STRUCTURE ONLEACHATE CHARACTERISTICS Wang Qi et al 69 Abstract Two large scale landfilling installations were built according to semi-aerobic landfilling and anaerobic landfilling theories. The concentrations of CODCr, BOD5andNH3-N were detected regularly . The results showed that, the concentration of pollutants in leachate of semi- aerobic landfilling structure reduced more quickly than that in anaerobic landfilling structure. The pollutant concentrations in leachate of semi- aerobic landfilling structure reduced regularly , but which in aerobic landfilling leachate varied greatly in early period of experiment. Keywords semi -aerobic, municipal solid waste, landfill and leachate APPLICATION OFMODIFIEDOSCULATINGINENVIRONMENTALQUALITY ASSESSMENT ON SURFACE WATERCao Jianrong et al 72 Abstract As a multi-objective decision optimization , osculating has been used in assessment on environmental quality of surface water. Modified osculating considers environmental criteria as samples of environmental matrix. Osculating value of every sample is given to make sure the qualities of all surface water sections. Moreover, analytic hierarchy process was used to decide the contribution of each index . It makes the result of environmental quality assessment on surface water more scientific. Keywords osculating , analytic hierarchy process, surface water and environmental quality assessment STUDY ON THE SYNTHESIS OF A NEW CHROMOGENIC REAGENT AND ITS APPLICATION IN ENVIRONMENTAL MONITORINGZhang Chunniu et al 75 Abstract This paper reports the synthesis of the new reagent 1- 4 -nitrophenyl -3 - 5 -bromopyridyl -triazene NPBPDTand the color reaction of NPBPDT with mercury. In the presence of the surface active agent Triton X -100 and in the Na2B4O7-NaOH medium of pH 11. 5, the reagent a yellow complex withmercury in the molar ratio of 1∶ 2. The molar absorptivity is 2. 80105L mol cm by dual -wavelengh of 440 nm and determination wavelengh of 535 nm. Beer s law is obeyed in the range of 0 ～ 12 μ g 25 mL. The has been applied to the direct determination of mercury in waste water with satisfactory results. Keywords 1 - 4 -nitrophenyl -3 - 5 -bromopyridyl -triazene, mercury and color reaction STUDYONTHESFORDETERMININGTRACEALDEHYDEBY PHLOROGLUCINOLZhang Shulin 77 Abstract This article studies a new of determining trace aldehyde by phloroglucinol. The application conditions of color reagent are investigated. This is simple, convenient and less sort of reagent and the degree of accuracy and precision is higher. Keywords aldehyde, phloroglucinol and color reaction STUDYONATMOSPHERICENVIRONMENTALCAPACITYANDATMOSPHERIC ENVIRONMENTAL MANAGEMENT IN ENERGY HEAVY INDUSTRY AREALin Jiquan et al 79 Abstract The atmospheric environmental capacity in Longmen Energy Heavy Industry Area is calculated using a box model of different frequency of wind speed. The result shows that the capacity of sulfur dioxide andTSP is respectively 21 097. 72 t and 63 293. 15 t in a year. The of selecting data and benefit transfer approach are respectively put into use to add up systematically discharging capacity and calculate the unsystematically discharging amounts, and the amount of sulfur dioxide is 13 728. 79 t a, and TSP is 68 555. 97 t a. The using ratio of SO2of atmospheric environmental capacity is 71. 2, and TSP is 108. 1 on small wide speed and still wind occasion. The using ratio of SO2of atmospheric environmental capacity is 30. 1, and TSP is 109. 6 on gale occasion. The result shows air pollution is different in different conditions, that is to say, SO2comes from systematically discharging, comparative spare capacity is 7 368. 93 t a. And TSP is in excess of its capacity, flying dust about coal and uncovered floor are main pollution sources on gale occasion, and atmospheric pollution is produced by 5 ENVIRONMENTAL ENGINEERING Vol. 23,No. 4, Aug . , 2005