德国燃煤灰渣的综合利用

介绍德国燃煤灰渣的质量管理、灰渣的种类以及各类灰渣的综合利用途径，并对德国燃煤灰湘综合的特点进行了分析，以期对我国的燃煤灰渣综合利用起到启发及借鉴作用。     

美国电厂灰渣利用和处置近况

美国燃煤电厂目前年用煤量超过7.7亿吨,灰渣年产生量超过9000万吨。灰渣处置方法传统上以填地和灰池(水力冲灰灰场)为主。近10年来综合利用量稳步增加(1990年平均利用率24.4％,统计数字见表1)。不少电厂在厂区建设灰渣处理系统,将     

我们是怎样开展灰渣综合利用的

开展电厂灰渣综合利用,可以减少贮灰场地、除灰费用和用灰单位的原料耗量,其重要性是众所周知的。五十年代我国火电厂已开始利用粉煤灰作水泥掺合料。三十多年来,灰渣的应用途径不断增多,但由于种种原因利用总量还不很高,因此,我们不仅要     

美国A-S-H公司除灰系统的设计经验

搞好燃煤锅炉除灰系统的设计,既利于除尘器的运行维护,又利于粉煤灰的综合利用,应当引起有关部门的足够重视。为此,本刊发表美国A-S-H公司除灰渣系统设计中的部分经验,供读者参考。     

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、…     

炉渣脱水系统的工程设计

文中简要地叙述了灰渣分排的实际意义，介绍了炉渣脱水系统的工艺流程及输渣、脱水仓灰水析出等分部系统的设计与选择，分析了脱水系统工程投运后所获得的环境、经济效益。     

综合环境控制应成为火电厂污染治理的指导思想

以往火电厂污染治理措施大多偏重于单项治理,例如设计新厂或改造老厂时,对除尘、脱硫、除灰和灰渣综合利用等设施,往往各行其是,缺少综合考虑。本文介绍综合环境控制的重要意义、效益和一些做法。     

我国脱硫灰渣作为水泥原料及混合材的综合利用现状

阐述了固废物脱硫灰的成分与特点以及目前我国对脱硫灰渣作为水泥原料和混合材的利用现状，并分析了影响脱硫灰渣利用的主要问题和资源化利用提出的建议，对脱硫灰渣作为水泥原料及混合材的进一步发展和推广提供一些有益的参考。     

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。     

贮灰场与环境保护

本文介绍火力发电厂贮灰场的灰渣和灰水影响环境的种种现象。在总结以往贮灰场设计、施工和运行管理经验的基础上,提出了灰场设计应采取的环境保护措施。     

Advanced ash management technologies for CFBC ash

The combustion of high-sulphur coal demands the reduction of sulphur emissions. The sorbent most often used in sulphur capture technology is calcium-based. Ashes from technologies such as circulating fluidized bed combustion (CFBC), therefore, contain high calcium levels. The use and disposal of these ashes poses challenges, because of highly exothermic reactions with water, high-pH leachates, and excessive expansion of solidified materials. This paper looks at the potential of two post-combustion ash treatment processes, CERCHAR hydration and AWDS disposal, in solving these challenges. A high-sulphur coal-derived CFBC ash is examined, after CERCHAR hydration treatment, in conjunction with a conventionally hydrated ash, in a range of chemical, geotechnical and utilization scenarios. The ashes are used to make no-cement and roller-compacted concrete as well as Ash Water Dense Suspensions (AWDS). The solidified mortar paste from no-cement concrete is subjected to an extensive geochemical examination to determine how solidification progresses and strength develops, from a chemical point of view.     

Diopside-based glass-ceramics from MSW fly ash and bottom ash

By utilising MSW fly ash from the Shanghai Yuqiao municipal solid waste (MSW) incineration plant as the main raw material, diopside-based glass-ceramics were successfully synthesized in the laboratory by combining SiO(2), MgO and Al(2)O(3) or bottom ash as conditioner of the chemical compositions and TiO(2) as the nucleation agent. The optimum procedure for the glass-ceramics is as follows: melting at 1500 degrees C for 30 min, nucleating at 730 degrees C for 90 min, and crystallization at 880 degrees C for 10h. It has been shown that the diopside-based glass-ceramics made from MSW fly ash have a strong fixing capacity for heavy metals such as lead (Pb), chromium (Cr), cadmium (Cd) etc.     

Glass–ceramic from mixtures of bottom ash and fly ash

Along with the gradually increasing yield of the residues, appropriate management and treatment of the residues have become an urgent environmental protection problem. This work investigated the preparation of a glass–ceramic from a mixture of bottom ash and fly ash by petrurgic method. The nucleation and crystallization kinetics of the new glass–ceramic can be obtained by melting the mixture of 80% bottom ash and 20% fly ash at 950 °C, which was then cooled in the furnace for 1 h. Major minerals forming in the glass–ceramics mainly are gehlenite (Ca₂Al₂SiO₇) & akermanite (Ca₂MgSiO₇) and wollastonite (CaSiO₃). In addition, regarding chemical/mechanical properties, the chemical resistance showing durability, and the leaching concentration of heavy metals confirmed the possibility of engineering and construction applications of the most superior glass–ceramic product. Finally, petrurgic method of a mixture of bottom ash and fly ash at 950 °C represents a simple, inexpensive, and energy saving method compared with the conventional heat treatment.     

Comparative study on the characteristics of fly ash and bottom ash geopolymers

This research was conducted to compare geopolymers made from fly ash and ground bottom ash. Sodium hydroxide (NaOH) and sodium silicate (Na(2)SiO(3)) solutions were used as activators. A mass ratio of 1.5 Na(2)SiO(3)/NaOH and three concentrations of NaOH (5, 10, and 15M) were used; the geopolymers were cured at 65 degrees C for 48 h. A Fourier transform infrared spectrometer (FT-IR), differential scanning calorimeter (DSC), and scanning electron microscope (SEM) were used on the geopolymer pastes. Geopolymer mortars were also prepared in order to investigate compressive strength. The results show that both fly ash and bottom ash can be utilized as source materials for the production of geopolymers. The properties of the geopolymers are dependent on source materials and the NaOH concentration. Fly ash is more reactive and produces a higher degree of geopolymerization in comparison with bottom ash. The moderate NaOH concentration of 10 M is found to be suitable and gives fly ash and bottom ash geopolymer mortars with compressive strengths of 35 and 18 MPa.     

粉煤灰-粉煤灰合成沸石对Cs~+的固化

以电厂废弃物粉煤灰为原料、采用碱熔-水热法制备了粉煤灰合成A型沸石(以下简称沸石),再以沸石对溶液中的Cs+进行分离富集,最后在碱激发剂的作用下以粉煤灰和吸附后的沸石制得地聚合物固化体。对固化体的性能进行了评价,并探讨了固化机理。实验结果表明:在吸附温度25℃、初始Cs+质量浓度100 mg/L、固液比10.0 g/L的条件下,沸石对的Cs+的吸附率达98%,比粉煤灰提高了2倍以上;沸石掺量为20%~30%(w)时,固化体的抗压强度符合GB 14569.1—2011要求,固化体中Cs+的42 d浸出率和累计浸出分数均远优于GB 14569.1—2011限值,表现出优异的抗浸出性能。     

Enhancing performance and durability of slag made from incinerator bottom ash and fly ash

This work presents a method capable of melting the incinerator bottom ash and fly ash in a plasma furnace. The performance of slag and the strategies for recycling of bottom ash and fly ash are improved by adjusting chemical components of bottom ash and fly ash. Ashes are separated by a magnetic process to improve the performance of slag. Analytical results indicate that the air-cooled slag (ACS) and magnetic-separated slag (MSS) have hardness levels below 590 MPa, indicating fragility. Additionally, the hardness of crystallized slag (RTS) is between 655 and 686 MPa, indicating toughness. The leached concentrations of heavy metals for these three slags are all below the regulatory limits. ACS appears to have better chemical stability than MSS, and is not significantly different from RTS. In the potential alkali-silica reactivity of slag, MSS falls on the border between the harmless zone and the potentially harmful zone. ACS and RTS fall in the harmless zone. Hence, the magnetic separation procedure of ashes does not significantly improve the quality of slag. However, RTS appears to improve its quality.     

浅谈粉煤灰的资源化利用现状

粉煤灰是电力行业排放的主要固体废弃物,对其的资源化利用已成为环保的首要任务。对粉煤灰进行高附加值的资源化回收利用,是实现可持续发展的必经之路。介绍了大唐国际成功开发研制的从高铝粉煤灰中提取氧化铝技术,开辟了粉煤灰综合利用的新途径。     

Wastewater remediation using coal ash

 Small-scale domestic septic tanks discharge excess nutrients such as phosphorus and nitrogen, as well as pathogens, which can degrade local water supplies. Unfortunately, traditional chemical and physical treatments are not practicable for single-home dwellings. This work reports on a potentially attractive solution to protect local water supplies by using a low-cost industrial waste, coal ash, for contaminant removal. Coal ash is produced as a consequence of electric power generation. The majority of the ash is disposed of in landfills and surface impoundments, or stored on- or off-site, producing large hills or leveling valleys. Only a small portion of the ash is ever utilized, mainly by cement industries and road construction. For example, in Canada less than 25% is used. Therefore, if useful applications can be found, an opportunity exists to make better use of this waste material. Bench-scale laboratory experiments and full-scale field tests show that coal ash has the capacity to remove phosphorus from domestic waste water. The experimental and field data demonstrate that phosphate levels and calcium levels can be correlated, although not in a simple manner. In addition, the ash in packed beds removed total suspended solid (TSS), biological oxygen demand (BOD), ammonia nitrogen (NH₃—N), total Kjeldahl nitrogen (TKN), and E. coli. The removal of E. coli was close 100% in the cases studied. Received: May 20, 2002 / Accepted: October 5, 2002     

Large-scale utilization of desulfurization ash and fly ash for unfired production of high-strength road-base stones

Journal of Material Cycles and Waste Management - This paper utilizes desulfurization ash (DA), fly ash (FA) and ordinary Portland cement (OPC) to prepare unfired high-strength road-base stones by...     

Effect of addition of pond ash and fly ash on properties of ash-clay burnt bricks.

Two industrial solid waste products generated by Indian coal-fired power plants, namely pond ash and fly ash, were used in combination with local clay to develop building bricks. The clay were mixed with the two different ashes in the range 10 to 90 wt.%, hydraulically pressed and fired at 1000 degrees C. The fired products were characterized for various quality properties required for building bricks. The properties of the optimal compositions were compared with conventional red clay bricks including the developed microstructures and the comparative study generally showed that te ash-clay bricks were of superior quality to the conventional products.