贮灰场粉煤灰物理量测试方法的研究

1前言宝鸡发电厂的灰渣采用分排方式排放。除一部分粉煤灰干除后直接取出供综合利用外，大部分粉煤灰以干除湿排方式随冲灰水进入贮灰场，经重力沉淀积存在贮灰场中。为给贮灰场的管理和综合利用提供科学依据，笔者对存灰的含水率、真比重、干容重、湿容重等物理技术参数进行了测定研究。现将其测试方法和测定结果作一简介。2粉煤灰物理量的测试方法及测定结果2．1试样采集技技术规范在灰场停运一个月之后进行取样。将灰装入干净干燥的广口玻璃瓶中，加盖后带回实验室，以供测试。2．2测试仪器100ml量筒、分析天平、托盘天平、恒温干燥箱、…     

新型负压气力除灰系统

以往我国燃煤电厂广泛采用水力除灰方式,在环境保护、水资源消耗、干灰综合利用和冲灰管运行等方面均带来一定的问题.随着电力工业的发展,大容量机组数量愈来愈多,飞灰排放量迅猛增加.国内原有干灰输送设备的规格和品种不全,问题较多。已不能满足电厂需要.1986年初。我厂与能源部郑州机械设计研究所、合肥发电厂合作,消化、吸收了美国A-S-H公司的气力除灰先进技术,研制出新型负压气力除灰设备及系统,安装在合肥电厂3号机组(125MW)进行工业性试验.1988年底安装、调试结束,1989年元月投入试运行.本文介绍该系统简要情况和试验结果.     

火电厂灰渣浸溶特性及冲灰过程中铬、铅的迁移转化规律研究

通过对电厂除灰系统结构、冲灰用水种类、灰水比的调查，对除尘器下干灰进行标准和模拟浸溶试验，研究灰渣浸溶特性和六价铬、铅在冲灰过程中的迁移转化规律，从而为进一步开展重金属污染防治和减小灰场灰水对周围环境的影响提供理论依据。     

焦作电厂袋式除尘器与脱硫系统应用分析

介绍了焦作电厂6台670t／h燃煤锅炉袋式（电）除尘器、脱硫、干除灰改造工程技术特点、运行情况及环保验收监测性能指标．重点对袋式除尘器与脱硫配套应用效果进行分析和探讨。     

干灰调湿碾压试验取得成效

由华北电力设计院等单位共同进行的干贮灰场试验,已取得较为满意的成果。灰场建于石景山电厂附近的山坡地上,面积6000m~2,库容80000m~3,可模拟山谷干灰场和平原干灰场。高井电站的干灰从贮灰库出来,经φ1000/2500型湿搅拌机,加水搅拌成湿灰,然后由铸石槽箱刮板机卸入自卸汽车,运至试验场碾压。     

火电厂除灰管结垢倾向分析

本文根据溶解化学理论，对水力除灰系统冲灰水中常板出沉淀形成垢的组份进行化学平衡分析，推导出冲灰水析出沉淀的饱和pHs计算公式。以此为依据，对太原第二势电厂除灰管结垢倾向进行了分析，发现该厂除灰系统结垢的主要成分是亚硫酸钙，推断出结垢形成的大根位置，并对防垢技术和除垢技术进行了讨论。     

金竹山电厂灰水砷分布规律探讨

对金竹山火电厂锅炉干式旋风子除尘器、文丘里水膜除尘器以及电除尘器,水力冲灰方式排出的灰水,进行了灰水中砷含量测试,以及干灰的浸取试验,探讨了砷的分布规律,以及灰水中砷超标原因。     

火电厂干灰湿排系统结垢影响因素与结垢预测的人工神经网络方法研究

通过对几个电厂灰水试验研究，导出了干灰湿排灰水系统结垢主要影响因素，本文以试验研究为基础，提出了联合梯度算法，首次用人工神经网络方法对灰管结垢预测进行了探讨，为水质预测提供了一条新途径。     

双套管长距离干灰输送系统在330 MW机组上的应用

介绍了国电电力建设研究所的双套管输送干灰技术在国电谏壁发电厂330 MW机组第一电场长距离干输灰中的应用,重点介绍了系统设计、安装、调试和运行,以及系统性能测试情况.     

水力除灰系统除砷模拟试验研究

针对金竹山电厂水力除灰系统采用闭路循环，溢流灰水再利用的方案，设计了模拟试验台，对灰水闭路循环后水质变化进行了探讨，取得了较为满意的结果．     

粉煤灰及其制备沸石对高浓度氨氮的去除比较

以粉煤灰为原料,采用改进的水热合成法制备了粉煤灰沸石,并将粉煤灰和粉煤灰沸石用于高浓度氨氮的吸附去除。实验结果表明:在粉煤灰和粉煤灰沸石的投加量分别为0.10 g/m L和0.04 g/m L、反应体系p H为5~7、初始氨氮质量浓度为500 mg/L的条件下,分别吸附660 min和60 min,粉煤灰和粉煤灰沸石对氨氮的去除率分别约为20.1%和50.7%左右,粉煤灰沸石对高浓度氨氮的去除效果明显优于粉煤灰;粉煤灰和粉煤灰沸石对氨氮的吸附动力学行为符合准二级动力学方程;Langmuir和Freundlich等温吸附模型能较好地描述粉煤灰对氨氮的等温吸附过程,而粉煤灰沸石对氨氮的等温吸附过程则更适宜用线性模型和Freundlich模型描述。     

连州电厂湿法烟气脱硫石膏脱水与排放系统的设计和运行分析

详细分析了连州电厂石灰石／石膏湿法烟气脱硫石膏脱水与排放系统的设计和运行，探讨了脱硫石膏与灰渣水混排对电厂排放系统运行的影响，初步结果表明，混排方式对现有排灰渣管道的影响不大。     

Fly ash scrubbing in a novel dual flow scrubber

Scrubbers are used as particulate emission control devices with the increase in stringency of old regulations or promulgation of new regulations. Scrubbing of fly ash in a novel dual flow scrubber, i.e., one water filled bubble section and one section with water-spray, is reported in this article. The presented system included a tapered section in order to achieve the bubble regime. On the other hand, a two-phase critical flow atomizer was used for the generation of spray regime with high degree of spray uniformity. Experiments were carried out for studying the behavior of the system in terms of various pertinent variables. The fly ash removal mechanism was explained in terms of various physical interactions. Electrostatic effect was found to have an insignificant influence on the collection efficiency of fly ash. The removal efficiency was found to decrease with the increase in inlet fly ash loading in the bubble section while it was increased in the spray section. A compromise must, therefore, be struck while operating the scrubber for achieving the desired performance. The effects of other operating variables studied on the removal efficiency remained similar in the regimes under investigation. The combined effect was, however, that the spray regime was dominating. Experimentation also revealed that the bubble section collected particles down to 20 microm size. Detailed experimentation revealed that almost 100% removal efficiency (zero penetration) of fly ash could be achieved in the dual flow scrubber at a QL/QG ratio of 3.0 m3/1000 ACM (actual cubic meter). Almost zero penetration of fly ash particles, clearly demonstrated that the dual flow scrubber with its staging operations met with the stricter emission regulations for particulate matter. Selection of any particulate control device is intrinsically related to the performance as a function of various pertinent variables of the system. Correlations were, therefore, put forward for the prediction of the performances of the bubble and the spray sections in terms of various pertinent variables of the system. The overall removal efficiency achievable in the dual flow scrubber was predicted with the help of these correlations. The predicted values were in excellent agreement with the experimental values (well within +/-5.0% deviation). Comparison of the performance of the present system with the existing systems indicated that the bubble and spray sections either alone or in combination (as in a dual flow scrubber), was energy and efficiency-wise much better than the existing systems. The novelty of the system is also described.     

Removal of Cr6 + and Ni2+ from aqueous solution using bagasse and fly ash

Raw bagasse and fly ash, the waste generated in sugar mills and boilers respectively have been used as low-cost potential adsorbents. Raw bagasse was pretreated with 0.1N NaOH followed by 0.1N CH3COOH before its application. These low-cost adsorbents were used for the removal of chromium and nickel from an aqueous solution. The kinetics of adsorption and extent of adsorption at equilibrium are dependent on the physical and chemical characteristics of the adsorbent, adsorbate and experimental system. The effect of hydrogen ion concentration, contact time, sorbent dose, initial concentrations of adsorbate and adsorbent and particle size on the uptake of chromium and nickel were studied in batch experiments. The Sorption data has been correlated with Langmuir, Freundlich and Bhattacharya and Venkobachar adsorption models. The efficiencies of adsorbent materials for the removal of Cr(VI) and Ni(II) were found to be between 56.2 and 96.2% and 83.6 and 100%, respectively. These results were obtained at the optimized conditions of pH, contact time, sorbent dose, sorbate concentration of 100 mg/l and with the variation of adsorbent particles size between 0.075 and 4.75 mm. The order of selectivity is powdered activated carbon > bagasse > fly ash for Cr(VI) removal and powdered activated carbon > fly ash > bagasse for Ni(II) removal.     

Chemical sequential extraction of heavy metals and sulphur in bottom ash and in fly ash from a pulp and paper mill complex

A five-stage sequential extraction procedure was used to determine the distribution of 11 metals (Cd, Cr, Cu, Mo, Pb, Zn, As, Co, V, Ni, Ba), and sulphur (S) in bottom ash and in fly ash from a fluidized bed co-combustion (i.e. wood and peat) boiler of Stora Enso Oyj Oulu Mill at Oulu, Northern Finland, into the following fractions: (1) water-soluble fraction (H2O); (2) exchangeable fraction (CH3COOH); (3) easily reduced fraction (NH2OH-HCl); (4) oxidizable fraction (H2O2 + CH3COONH4); and (5) residual fraction (HF + HNO3 + HCl). Although metals were extractable in all fractions, the highest concentrations of most of the metals occurred in the residual fraction. From the environmental point of view, this fraction is the non-mobile fraction and is potentially the least harmful. The Ca concentrations of 29.3 g kg(-1) (dry weight) in bottom ash and of 68.5 g kg(-1) (dry weight) in fly ash were correspondingly approximately 18 and 43 times higher than the average value of 1.6 g kg(-1) (dry weight) in arable land in Central Finland. The ashes were strongly alkaline pH (approximately 12) and had a liming effects of 9.3% (bottom ash) and 13% (fly ash) expressed as Ca equivalents (dry weight). The elevated Ca concentrations indicate that the ashes are potential agents for soil remediation and for improving soil fertility. The pH and liming effect values indicate that the ashes also have a pH buffering capacity. From the environmental point of view, it is notable that the heavy metal concentrations in both types of ash were lower than the Finnish criteria for ash utilization.     

粉煤灰的改性、成型及深度除磷应用

选择合适的改性剂对粉煤灰进行改性,通过有机高分子交联方法对改性粉煤灰进行成型处理,并采用静态吸附法评价改性粉煤灰的深度除磷效果。采用1 g氢氧化铝改性粉煤灰处理100 mL磷质量浓度为10.0 mg/L的模拟废水,磷去除率可达99.70％,处理后模拟废水中磷质量浓度低于0.50 mg/L, 达到GB8978-1996《污水综合排放标准》。成型处理可提高粉煤灰的沉降速率,改善灰水分离效果。经超声再生后的成型氢氧化铝改性粉煤灰的磷去除率仍可达67.9％。     

半干法脱硫配套电除尘器选型分析

某新建135MW机组锅炉为循环化床锅炉,其烟气处理系统采用半干法脱硫工艺加电除尘器。由于半干法脱硫后电除尘器入口的粉尘浓度非常高,且烟尘理化性质发生较大变化,除尘难度大,常规电除尘器的选型很难适应。分析了半干法脱硫后电除尘器选型的影响因素及各系数取值。     

粉煤灰处理阴离子表面活性剂废水及机理研究

采用粉煤灰作为吸附混凝剂,研究了粉煤灰对废水中阴离子表面活性剂十二烷基磺酸钠（SDS）的去除及机理。分析了粉煤灰投加量、吸附时间、pH值对废水中SDS去除率的影响,探讨了最佳条件下废水中SDS去除率,研究了粉煤灰动力学特征。结果表明,在200mL浓度50mg/L的SDS溶液中,调节pH值为13,加入70 g粉煤灰,搅拌20m in后,SDS的去除率为83.3%。粉煤灰对SDS的吸附符合Freund lich吸附等温式。     

钛硅分子筛催化双氧水氧化水中间甲酚

探索催化双氧水氧化去除间甲酚对开发炼油厂碱渣废水处理新技术意义重大。采用钛硅分子筛催化双氧水氧化水中间甲酚,考察了反应时间、反应温度、双氧水加入量、催化剂加入量和初始溶液pH对间甲酚去除率的影响。实验结果表明：钛硅分子筛对双氧水氧化间甲酚具有显著的催化作用;在反应时间为90 min、反应温度为80 ℃、n（H₂O₂）∶n（间甲酚）为4、催化剂加入量为1.5 g/L、初始溶液pH为1.0~11.0的条件下,间甲酚去除率约为94%,间甲酚溶液的BOD₅/COD从氧化前的0.26提高到氧化后的0.38,可生化性显著提高。