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991.
飞灰及其混合脱硫剂浆液脱硫特性的实验研究 总被引:3,自引:0,他引:3
从碱性物溶出率和脱硫容量两个方面,对杭州地区3种电厂飞灰和飞灰-大理石混合脱硫剂进行了实验研究。结果表明,降低pH值有利于飞灰中碱性物的溶出,pH为5-8时,飞灰中碱性物溶出率约为30%。不同电厂飞灰的脱硫容量差异较大,为0.12-0.25gSO2/g飞灰,相当于石灰石脱硫容量的23%-48%。飞灰-大理石混合脱硫剂中飞灰与大理石之间具有相互协同促进作用,对飞灰:大理石为1:1的混合脱硫剂,其脱硫容量Ws60比大理石提高了30%。当脱硫率要求不太高时,可考虑使用飞灰-大理石混合脱硫剂,以部分或全部取代石灰石脱硫剂,从而大大降低脱硫剂成本。 相似文献
992.
993.
Arditsoglou A Terzi E Kalaitzoglou M Samara C 《Environmental science and pollution research international》2003,10(6):354-356
The recovery of polycyclic aromatic hydrocarbons (PAHs) from lignite coal burnt in Greek power stations and the fly ash produced is examined comparatively using Soxhlet, ultrasonic and accelerated solvent extraction procedures with various organic solvents. Soxhlet using toluene/methanol mixture and accelerated solvent extraction/toluene were found to be the most efficient methods for fly ash PAHs, yielding average recoveries of about 80%. The accelerated solvent extraction/toluene procedure was superior for lignite PAHs, yielding 96% average recovery, whereas ultrasonic and Soxhlet extraction yielded relatively lower recoveries (75% and 67%, respectively). 相似文献
994.
垃圾焚烧厂焚烧底灰的处理研究 总被引:12,自引:1,他引:12
系统地研究了常州市环境卫生综合厂垃圾焚烧车间的底灰。研究结果表明,根据中国现行的污染控制标准,该厂的底灰属于一般废物,可以以建筑垃圾的方式处理。但对底灰的分选和分类研究结果表明,底灰含有一定量的未燃烬的有机废物,也有一些可回收利用的废物。因此,底灰应该先分选后,再对无利用价值的渣土作填埋或其他处置。 相似文献
995.
996.
研究了利用电厂粉煤灰作为非均相催化剂,催化H2O2氧化对氨基苯酚(PAP),讨论了各种因素对PAP去除率的影响。结果表明,在30℃,pH=1.5,H2O2和PAP的起始浓度分别为0.50mol/L和0.10mol/L,反应时间为100min,粉煤灰用量为6.0%,搅拌速度为1000r/min的条件下,粉煤灰具有良好的催化活性,能有效地催化H2O2氧化PAP,PAP的去除率可达81%左右。该法可用于预处理含PAP的工业废水。 相似文献
997.
Pekárek V Karban J Fiserová E Bures M Pacáková V Vecerníková E 《Environmental science and pollution research international》2003,10(1):39-43
BACKGROUND, AIMS AND SCOPE: It is well known that the fly ash from filters of municipal waste incinerators (MWI-FA) shows dehalogenation properties after heating it to 240-450 degrees C. However, this property is not general, and fly ash samples do not possess dehalogenation ability at all in many cases. Fly ash has a very variable composition, and the state of the fly ash matter therefore plays the decisive role. In the present paper, the function of important components responsible for the dehalogenation activity of MWI-FA is analysed and compared with the model fly ash. METHODS: With the aim of accounting for the dehalogenation activity of MWI-FA, the following studies of hexachlorobenzene (HCB) dechlorination were performed: The role of copper in dehalogenation experiments was evaluated for five types of metallic copper. The gasification of carbon in MWI-FA was studied in the 250-350 degrees C temperature range. Five different kinds of carbon were used, combined with conventional Cu(o) and activated nanosize copper powder. The dechlorination experiments were also carried out with Cu(II) compounds such as CuO, Cu(OH)2, CuCl2 and CuSO4. The results were discussed from the standpoint of thermodynamics of potential reactions. Based on these results, the model of fly ash was proposed, containing silica gel, metallic copper and carbon. The dechlorination ability of MWI-FA and the model fly ash are compared under oxygen-deficient atmosphere. CONCLUSIONS: The results show that, under given experimental conditions, copper acts in the dechlorination as a stoichiometric agent rather than as a catalyst. The increased surface activity of copper enhances its dechlorination activity. It was found further that the presence of copper leads to a decrease in the temperature of carbon gasification. The cyclic valence change from Cu(o) to Cu+ or Cu2+ is a prerequisite for the dehalogenation to take place. RECOMMENDATION AND OUTLOOK: Thermodynamic analysis of the dechlorination effect, as well as the comparison of dechlorination pathways on MWI-FA and model fly ash, can provide a deeper understanding of the studied reaction. 相似文献
998.
Stabilized Coal Ash Artificial Reef Studies 总被引:1,自引:0,他引:1
In 1989, an experimental stabilized coal ash reef was deployed in Poole Bay off the southern coast of the UK. Three different mixtures of pulverised fuel ash, gypsum, flue gas desulphurisation sludge and cement were used along with concrete controls. the aim was to study the environmental compatibility of the reef materials through heavy metal analyses of the blocks to determine if any leaching or changes were occurring. at the same time, reef encrusting and associated biota have been analyzed together with material from concrete control and natural reefs to determine if there was any evidence for excess bioaccumulation.
This paper presents the results from studies of sectioned reef blocks immersed for 3 and 4 years. No significant change in levels of heavy metals (Cd, Cr, Cu, Mn, Ni, Pb, Zn) has been detected. Surface loss of calcium, presumably associated with the gypsum component, is confirmed with evidence of replacement by magnesium. Trends in data suggest initial surface changes which slow with time.
Epibiota have been analyzed for heavy metal content. the variety of reef-associated organisms has been extended to include mobile, resident species which are higher in the food chain: molluscs, crustaceans and territorial fish. No consistent evidence of bioaccumulation of a range of heavy metals (above those levels found in organisms associated with control reefs) has been detected. Monitoring of the encrusting species range and densities shows little difference between colonisation of the concrete and ash mixture blocks. 相似文献
This paper presents the results from studies of sectioned reef blocks immersed for 3 and 4 years. No significant change in levels of heavy metals (Cd, Cr, Cu, Mn, Ni, Pb, Zn) has been detected. Surface loss of calcium, presumably associated with the gypsum component, is confirmed with evidence of replacement by magnesium. Trends in data suggest initial surface changes which slow with time.
Epibiota have been analyzed for heavy metal content. the variety of reef-associated organisms has been extended to include mobile, resident species which are higher in the food chain: molluscs, crustaceans and territorial fish. No consistent evidence of bioaccumulation of a range of heavy metals (above those levels found in organisms associated with control reefs) has been detected. Monitoring of the encrusting species range and densities shows little difference between colonisation of the concrete and ash mixture blocks. 相似文献
999.
1000.
改性粉煤灰填充聚丙烯酸钠高吸水性树脂合成工艺研究 总被引:1,自引:0,他引:1
改性粉煤灰与丙烯酸通过水溶液聚合法制备出粉煤灰/聚丙烯酸钠高吸水性复合材料。采用单因素法,分析了中和度、聚合温度、反应时间及静置分层处理对高吸水性复合材料吸水性能和耐盐性能的影响。实验结果表明:当中和度为50%、聚合温度为70℃、反应时间为5h时且静置分层处理所制备的高吸水性复合材料具有最佳的吸水性能。 相似文献