共查询到20条相似文献,搜索用时 453 毫秒
1.
《再生资源与循环经济》2020,(9)
分析了几类主要冶金、化工固体废物的组成,归纳了尾矿、矿渣、粉煤灰、煤矸石、钢渣、脱硫石膏、磷石膏的主要应用途径和当前研究进展,总结其在再生利用和发展过程中存在的一些问题,提出一些可行性建议。 相似文献
2.
蒋屹欧阳寿林 《再生资源与循环经济》2022,(7):37-39
介绍了以中钛型粒化高炉渣为基础,通过配加普通粒化高炉渣和自制活性剂的方式,实现矿渣微粉活性的提升,最终制备出符合国家标准的S75级含钛矿渣微粉产品的工艺方法。对自制活性剂配置原理、配比组成等进行介绍与分析,旨在为同类工艺研究提供参考条件,并希望以此为基础不断优化含钛矿渣微粉制备技术,推动行业进步。 相似文献
3.
4.
《再生资源与循环经济》2015,(8)
用建筑垃圾废弃混凝土再生粉体按一定比例部分替代高炉矿渣粉,设定不同替代比例进行胶砂实验,通过测试7 d和28 d抗压强度,对比不同替代比例对高炉矿渣粉活性的影响,实验表明废弃混凝土粉体部分替代高炉矿渣粉对早期强度影响很小,但对其后期强度有一定影响,通过控制适当比例,可有效保证产品质量,且不会对产品的吸水率造成明显影响。同时,选定废弃混凝土细集料掺混比例为10%进行两种物料的混磨性能试验。粉磨时间分别设定20 min,35 min,50 min,65 min和80 min。通过对比各时间段物料的比表面积来分析其易磨性,实验表明废弃混凝土细集料比高炉矿渣的易磨性好,但单磨时会出现团聚现象;通过混掺共磨可以提高高炉矿渣粉磨效率、降低粉磨时间、节约粉磨能耗,具有一定的助磨作用。 相似文献
5.
6.
铜陵化学工业集团公司近日研制成功利用工业废渣磷石膏制新型建筑墙体砖技术。这是该公司继利用磷石膏制建筑用石膏板、高水材料、水泥缓凝剂等产品之后取得的又一重大科研成果。磷石膏是磷酸化工产品生产过程中产生的一种工业废渣。据了解 ,目前我国现有大型磷酸二铵生产装置 5套 ,生产能力达 1 0 0万t/a左右 ,磷石膏排放量约为 30 0万 t/a。铜化集团公司现有一套 1 2万 t/a的大型磷酸二铵生产装置 ,磷石膏的排放量达 30万 t/a左右 ,加之现已开工建设的磷铵技改工程的上马 ,估计磷石膏的排放量将达到 1 0 0万 t/a左右。为有效解决磷石膏的… 相似文献
7.
8.
《再生资源与循环经济》2019,(11)
<正>我国磷石膏年产生量约7 500万t,综合利用率不足40%,磷石膏产生量大,综合利用成本较高,大量磷石膏长期堆存,不仅占用土地,而且存在较大环境安全隐患。特别是长江沿线,磷化工企业较多,磷石膏大量堆存给长江经济带生态保护带来很大压力。为此,积极开展相关调研所取各方意见建议,研究推动磷石膏综合利用的相关政策措施鼓励和支持企业开展磷石膏综合利用。 相似文献
9.
10.
本研究利用矿渣硅酸水泥及粒化高炉矿渣,研制出硅酸盐脱硫剂,对沸腾床燃用高硫无烟煤有较好的脱硫能力. 相似文献
11.
Effect of industrial by-products containing electron acceptors on mitigating methane emission during rice cultivation 总被引:1,自引:0,他引:1
Muhammad Aslam Ali Chang Hoon Lee Sang Yoon Kim Pil Joo Kim 《Waste management (New York, N.Y.)》2009,29(10):2759-2764
Three industrial by-products (fly ash, phosphogypsum and blast furnace slag), were evaluated for their potential re-use as soil amendments to reduce methane (CH4) emission resulting from rice cultivation. In laboratory incubations, CH4 production rates from anoxic soil slurries were significantly reduced at amendment levels of 0.5%, 1%, 2% and 5% (wt wt−1), while observed CO2 production rates were enhanced. The level of suppression in methane production was the highest for phosphogypsum, followed by blast slag and then fly ash. In the greenhouse experiment, CH4 emission rates from the rice planted potted soils significantly decreased with the increasing levels (2–20 Mg ha−1) of the selected amendments applied, while rice yield simultaneously increased compared to the control treatment. At 10 Mg ha−1 application level of the amendments, total seasonal CH4 emissions were reduced by 20%, 27% and 25%, while rice grain yields were increased by 17%, 15% and 23% over the control with fly ash, phosphogypsum, and blast slag amendments, respectively. The suppression of CH4 production rates as well as total seasonal CH4 flux could be due to the increased concentrations of active iron, free iron, manganese oxides, and sulfate in the amended soil, which acted as electron acceptors and controlled methanogens’ activity by limiting substrates availability. Among the amendments, blast furnace slag and fly ash contributed mainly to improve the soil nutrients balance and increased the soil pH level towards neutral point, but soil acidity was developed with phosphogypsum application. Conclusively, blast slag among the selected amendments would be a suitable soil amendment for reducing CH4 emissions as well as sustaining rice productivity. 相似文献
12.
13.
Nabajyoti Saikia Geert Cornelis ?zlem Cizer Carlo Vandecasteele Dionys Van Gemert Koenraad Van Balen Tom Van Gerven 《Journal of Material Cycles and Waste Management》2012,14(2):102-112
The technical properties of cement mortars containing natural fine aggregate that is replaced by lead blast furnace slag at 25 and 35% level were assessed at fixed water-to-cement (W/C) ratio and at fixed flow table value. The leachabilities of some toxic elements from the cement mortars were also assessed to test the environmental suitability of the slag for use in preparation of cement mortar. At fixed W/C ratio, the strength of the mortar decreased with increase of the slag content. On the other hand, at fixed consistency, strength increased with increasing slag content in the mortar composition. The concentrations of some toxic elements in the leachates collected from the mortars containing slag were slightly higher than for the control mortar, but the concentrations in the leachates remained within the regulatory limits for recycling in construction applications. For most elements, leaching from a mortar containing 35% of slag was similar to that from a mortar containing 25% of slag. Therefore, 35% of natural sand can be beneficially replaced with Pb slag to produce cement mortar without affecting the mechanical and leaching properties studied in this work. 相似文献
14.
Several methods of reprocessing metallurgical (blast furnace) slag into materials for the building industry, based on melting aggregates with submerged combustion, were developed and tested. The first method involves melting hot slag with some additives directly in a slag ladle with a submerged gas-air burner, with the objective of producing stabilized slag or glass-ceramic. The second method involves direct draining of melted slag from a ladle into the slag receiver, with subsequent control of the slag draining into the converter where special charging materials are added to the melt, with the objective of producing glass-ceramic. A third method involves melting cold slag with some additives inside a melting converter with submerged gas-air burners, with the objective of producing glass-ceramic fillers for use in road construction. Specific to the melting process is the use of a gas-air mixture with direct combustion inside the melt. This feature provides melt bubbling to help achieve maximum heat transfer from combustion products to the melt, improve mixing (and therefore homogeneity of the melt), and increases the rate of chemical reactions. The experimental data for different aspects of the proposed methods are presented. The reprocessed blast-furnace slag in the form of granules can be used as fillers for concretes, asphalts, and as additives in the production of cement, bricks and other building materials. As well, reprocessed blast-furnace slag can be poured into forms for the production of glass-ceramic tiles. 相似文献
15.
Improvement of permeability of waste sludge by mixing with slag or construction and demolition waste
Hiroshi Asakura Kazuto Endo Masato Yamada Yuzo Inoue Yusaku Ono 《Waste management (New York, N.Y.)》2009,29(6):1877-1884
To determine the allowable ratio of waste sludge required to ensure an aerobic zone in the landfill, we investigated sludge permeability, which involved mixing sludge, the major landfill waste in Japan, at different mixing ratios with other wastes (slag and construction and demolition waste (C&D)). We measured parameters of sample permeability and analyzed parameters that exert a large influence on oxygen penetration depth with a simulation model accounting for both diffusion and convection driven by temperature gradients. We also determined the critical volumetric contents in which gas and/or water permeability change significantly when sludge is mixed with sand or gravel. From the results of the simulations, gas permeability of the layer, the difference between inside and outside temperatures and the oxygen consumption rate exert a large influence on the resulting oxygen penetration depth. The allowable ratio of sludge required to ensure an aerobic zone in the landfill was determined by considering the balance of the above three parameters. By keeping volumetric sludge content to below 25%, air convection and oxygen penetration depth of several meters were achieved in the modeling. 相似文献
16.
17.
Coastal areas in Japan and other parts of the world have serious problems with barren grounds. A method has been developed that uses a mixture of steelmaking slag and compost including humic substances supplied in seawater, for restoring seaweed beds. The effects of this method have been previously confirmed in field tests. It was found that the mixture of steelmaking slag and compost was effective for extending the lifetime of iron elution as well as increasing iron concentrations in seawater. In this study, the effect of the mixing composts with steelmaking slag was evaluated additionally for increasing dissolved iron concentrations in seawater. The characteristics of iron elution were also studied using this method. In particular, the mechanism of Fe elution and dissolved Fe oxidation was examined in detail. The iron elution of actual seawaters was tested using three kinds of samples which involved steelmaking slag, compost, and a mixture of steelmaking slag and compost. These samples were used to understand the mechanism of Fe elution and oxidation in seawater. It was found that the mixture of steelmaking slag and compost was the most effective, which also confirmed the validity of the proposed Fe elution process in seawater. 相似文献
18.
Within the European Union, it is estimated that between 8 and 9 million tonnes of waste electric and electronic equipment (WEEE) arises annually, of which television sets and computers account for an important part. Traditionally, Cathode Ray Tubes (CRT) have been used for TVs and computer monitors, but are rapidly being replaced by flat-screen technology. Only part of the discarded CRT glass is being recycled. Primary smelters use large amounts of silica flux to form iron-silicate slag, and can, in most cases, tolerate lead input. Use of discarded CRT glass in copper smelting is a potential alternative for utilization of the glass.The mineralogical composition of a slag sampled during ordinary slag praxis has been compared with that of a mixture of slag and CRT glass when re-melted and slowly cooled. Slag (iron-silicate slag) from Boliden Mineral AB, Sweden, was used for the experiments. Slag and glass have been mixed in various proportions: pure slag, pure glass, 90% slag-10% glass and 65% slag-35% glass, and heated in an inert atmosphere up to 1400 °C in a Netzsch Thermal Analysis (TA) instrument. The re-melted material has been analyzed using X-ray diffraction (XRD) and scanning electron microscopy (SEM) to determine changes in mineralogical composition after mixing with glass.The results show that the main mineralogical component of the slag is fayalite; the CRT glass is amorphous. The main crystalline phases of the slag do not change with addition of glass. An amorphous phase appears when the addition of glass is increased, which gives the sample a different structure. 相似文献
19.
开展了氯氧化锆生产排放废硅渣中锆资源的回收工艺研究,结果表明,当废硅渣在50℃条件下溶解废碱液时,硅渣中夹带的未熔锆英砂可以沉积,回收率可达到98.5%以上。继续加热溶硅碱液,可溶锆可与硅产生凝聚,形成锆富集物沉淀,锆富集物中湿基的ZrO2含量最高可达6.5%,可溶锆的回收率在97%以上。回收得到的未熔砂和锆富集物可直接返回氯氧化锆主流程中再利用,从而实现硅渣中锆的资源化利用。 相似文献
20.
Volatilization behavior of lead from molten slag under conditions simulating municipal solid waste melting 总被引:1,自引:0,他引:1
Hiroyuki Nakada Naoto Mihara Yuuki Kawaguchi Shohichi Osada Dalibor Kuchar Hitoki Matsuda 《Journal of Material Cycles and Waste Management》2008,10(1):19-23
To reutilize molten slag derived from an ash melting process, the lead volatilization mechanism under reducing conditions
was investigated. Reducing conditions were established by introducing a CO-CO2-N2 gas mixture to the reactor or by adding graphite to the molten slag prior to the experiments. As samples, two types of simulated
molten slag composed of CaO-SiO2-Al2O3 mixed with PbO were used and the lead volatilization behavior was studied at 1773 K. It was found that the lead volatilization
rate increased on increasing the amount of reducing agent for both graphite and the CO-CO2 gas mixture. For the CO-CO2 reducing gas mixture, this increase was mainly attributed to PbO conversion to Pb. For the addition of graphite, the increase
in lead volatilization ratio was considered to partially result from PbO conversion to Pb and partially from a reaction of
graphite with SiO2 yielding volatile SiO. The volatile SiO gas was then emitted from the furnace, which brought about a reduction in the SiO2 content of the slag. As a result, the slag viscosity decreased, which led to an enhancement of the lead volatilization ratio. 相似文献