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101.
102.
电石渣在环氧丙烷生产中的循环利用 总被引:1,自引:0,他引:1
总结了电石渣生产环氧丙烷工艺中的设计与应用。运行情况表明,该工艺具有明显的经济效益和社会效益。 相似文献
103.
电石渣浆的综合治理与利用 总被引:5,自引:0,他引:5
介绍了综合治理电石乙炔法生产 PV C 时产生电石渣浆的工艺技术。采用电石渣浆废水全部 闭路循环回用工 艺,实现电石 渣浆上清液 的回收利用;同时以电石渣 代替熟石灰用 于环氧丙烷的生产。取得了显著的经济效益和社会环境效益。 相似文献
104.
105.
Oxidation and reduction processes on coal- and mineral-pyrite surfaces have been investigated to better understand the reactions that control the hydrophobicity and flotation behavior of pyrite. The incipient oxidation and reduction reactions were studied using fresh surfaces of pyrite that were created by in situ fracturing electrodes potentiostated at a predetermined potential. Chronoamperometry immediately after fracture and subsequent cyclic voltammetry have established that fresh fracture surfaces of pyrite instantaneously assume a unique potential (referred to as the “stable” potential) at which neither oxidation nor reduction takes place. For Peruvian and Chinese pyrites, the stable potential is −0.28 V (standard hydrogen electrode, SHE) at pH 9.2 and 0 V at pH 4.6. The initial oxidation of pyrite begins at potentials slightly positive of the stable potential and is believed to produce a hydrophobic sulfur-rich species, most likely a polysulfide or metal-deficient sulfide. A rotating ring-disc electrode (RRDE) was employed to study the kinetics and mechanisms of surface reactions on pyrite over moderate potential ranges. Two distinct soluble reduction products (ferrous hydroxide and HS−) and one distinct soluble oxidation product (ferrous hydroxide) were observed on pyrite in alkaline solutions. It is concluded that the initial oxidation of pyrite and the oxidation of ferrous to ferric hydroxide occur in a similar potential range. When the electrode is oxidized, e.g. by polishing, prior to experiments, the initial oxidation of pyrite is masked by the oxidation of ferrous hydroxide, making it difficult to study the oxidation of pyrite itself. 相似文献
106.
107.
Properties of concrete pavements prepared with ferrochromium slag as concrete aggregate 总被引:1,自引:0,他引:1
J. Zeli 《Cement and Concrete Research》2005,35(12):2340-2349
This paper presents the results of investigation related to both the properties of the ferrochromium slag and the standard physical and mechanical properties of Portland cement concrete pavements (PCCP) made with this slag as aggregate, according to the relevant Croatian standards. Slag is formed as a liquid at 1700 °C in the manufacture of the high-carbon ferrochromium metal and, by slow cooling in the air, the slag crystallizes to give a stable CaO–MgO–Al2O3–silicate product with mechanical properties similar to basalt. With a proper selection of slag as an artificial aggregate, concrete pavements with compressive strengths, wear resistance and specific weight higher than in those from natural (limestone) aggregate in commercial Portland cement, type CEM II/B-S 42.5 (EN 197), can be made. The 28-day compressive strength of the concretes made with original unfractioned slag and with standard limestone as aggregates (w/c=0.64 and 350 kg/m3) reached the values of 57.00 MPa and 36.70 MPa, respectively. Volume stability, high volume mass, good abrasion resistance to wear and crushability make this reinforced slag concrete suitable for wearing courses of concrete pavements for traffic load classes 1 and 2 where carbonate stone material (limestone) mainly does not meet the Standard Technical Requirements for cement concrete slab pavements according to the relevant Croatian standard. 相似文献
108.
用冶金渣制备聚硅硫酸铁的研究 总被引:2,自引:0,他引:2
用钢渣和水渣制备出聚硅硫酸铁,分析了影响因素,制备的聚硅硫酸铁净水用量少、无毒、混凝效果好。 相似文献
109.
Zhiheng Wu 《Fuel》2007,86(14):2194-2200
A UK bituminous coal has been used to study demineralization by two-stage chemical leaching. The first-stage uses hydrofluoric acid (HF) at 65 °C and reduces the ash content from 5.30 wt% to 1.37 wt% by mainly removing Al and Si containing minerals. Subsequent leaching by ferric ions decreases the ash content further to 990 ppm by removing most of the pyrite and fluorides formed during the HF leaching. Calorific value of the coal shows no change following leaching, which suggests no oxidation is occurring to the coal carbonaceous matrix. The mercury and sulfur contents after the two-stage leaching sequence decrease by 40% and 26%, respectively. 相似文献
110.
湖北某水泥厂在8.3万T立窑水泥生产线上,成功地开发高铁早强矿渣水泥,并通过了国家建材局水泥专家参加的省级鉴定。该水泥具有早强高,硬化快,抗硫酸盐侵蚀和胶凝性能好等性。 相似文献