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61.
为分离回收废锂电池中的铝,在含铁及含铁锰的两种碱浸液中构建了金属(Me)-OH--CO32-,Me-OH--NH3,Me-OH--NH3-CO32-三种配合-沉淀体系,分析了三种体系在不同pH条件下的铝去除率和Al(OH)3沉淀中的铁及铁锰含量。实验结果表明:含铁碱浸液在pH为8.0~10.0的适宜条件下,Me-OH--CO32-、Me-OH--NH3和Me-OH--NH3-CO32-体系的铝去除率分别高达99.4%、99.7%和99.6%,Al(OH)3沉淀中含少量铁,Me-OH--NH3-CO32-体系生成的Al(OH)3沉淀比Me-OH--NH3 体系的Al(OH)3沉淀更易分离;含铁锰碱浸液Me-OH--CO32-、Me-OH--NH3和Me-OH--NH3-CO32-体系的铝去除率分别高达99.4%,99.7%和99.9%,Al(OH)3沉淀中几乎不含锰,含有少量铁。  相似文献   
62.
刘腾  邱兆富  杨骥  曹礼梅  张巍 《化工环保》2015,35(2):159-164
根据我国每年的石油消费量估算了当年的废炼油催化剂产生量,预测2015年我国废炼油催化剂的产生量将达到2.07×105 t。介绍了废炼油催化剂的主要成分、含量与危害,分别论述了废流化催化裂化催化剂、废催化加氢催化剂和废催化重整催化剂的处理和利用方法,指出废炼油催化剂的再生及资源化和无害化应是未来的重点研究方向。  相似文献   
63.
再谈废催化剂中金属的回收   总被引:5,自引:0,他引:5  
孟宪红  李悦 《化工环保》1998,18(5):277-280
介绍了含钯,钴,钼,钨的废催化剂的来源及从废催化剂中回收上述金属的工艺。  相似文献   
64.
催化湿式氧化处理碱渣废水的研究   总被引:30,自引:0,他引:30  
以催化湿式氧化 (CWO)技术对碱渣废水进行治理 ,考察了各种反应条件对废水处理效果的影响。结果表明 ,在 2 30℃ ,6 6MPa ,空速 8h-1的反应条件下 ,CODCr的去除率 78% ,硫的去除率达到 99% ,BOD5/CODCr超过 0 8,并对CWO处理后的尾气进行了分析 ,表明除空气和CO2 以外没有其它有害气体。  相似文献   
65.
本文对Lix5 4 10 0萃取剂萃取铜氨料液中铜的性能做了研究 ,发现其具有动力学速率快、饱和容量高、分离效果好、反萃容易及不萃氨等特点。并把其应用于印刷电路板蚀刻废液中铜的回收 ,在铜初始浓度为 15 6.96g/L ,相比为 2∶1条件下 ,用 80 %Lix5 4 10 0 -煤油经过三级错流萃取 ,铜的浓度可下降到 2 6.88g/L。三级总萃取率达 82 .87%。由此设计推荐了无废排放工艺流程 ,实现了经济效益和环境效益的统一  相似文献   
66.
The North Atlantic right whale (NARW) (Eubalaena glacialis) is one of the world's most threatened whales. It came close to extinction after nearly a millennium of exploitation and currently persists as a population of only approximately 500 individuals. Setting appropriate conservation targets for this species requires an understanding of its historical population size, as a baseline for measuring levels of depletion and progress toward recovery. This is made difficult by the scarcity of records over this species’ long whaling history. We sought to estimate the preexploitation population size of the North Atlantic right whale and understand how this species was distributed across its range. We used a spatially explicit data set on historical catches of North Pacific right whales (NPRWs) (Eubalaena japonica) to model the relationship between right whale relative density and the environment during the summer feeding season. Assuming the 2 right whale species select similar environments, we projected this model to the North Atlantic to predict how the relative abundance of NARWs varied across their range. We calibrated these relative abundances with estimates of the NPRW total prewhaling population size to obtain high and low estimates for the overall NARW population size prior to exploitation. The model predicted 9,075–21,328 right whales in the North Atlantic. The current NARW population is thus <6% of the historical North Atlantic carrying capacity and has enormous potential for recovery. According to the model, in June–September NARWs concentrated in 2 main feeding areas: east of the Grand Banks of Newfoundland and in the Norwegian Sea. These 2 areas may become important in the future as feeding grounds and may already be used more regularly by this endangered species than is thought.  相似文献   
67.
A 90-day study conducted to explore the potential of epigeic earthworms Eisenia foetida and Eisenia andrei to transform the different types of agricultural wastes and spent mushroom compost into value-added product, i.e., vermicompost. Vermicomposting resulted in significant reduction in C:N ratio, pH, electrical conductivity, total organic carbon, TK; and increase in total Kajeldahl nitrogen, TP, and various micro and macronutrients compared to those in the worm feed. Our trials demonstrated that the vermicomposting could be considered as an alternate technology for recycling and environmentally safe disposal/management of the mushroom cultivation complexes’ residues mixed with different types of agricultural waste using epigeic earthworms E. foetida and E. andrei.  相似文献   
68.
69.
Abstract: Quality of the agricultural matrix profoundly affects biodiversity and dispersal in agricultural areas. Vegetatively complex coffee agroecosystems maintain species richness at larger distances from the forest. Epiphytes colonize canopy trees and provide resources for birds and insects and thus effects of agricultural production on epiphytes may affect other species. We compared diversity, composition, and vertical stratification of epiphytes in a forest fragment and in two coffee farms differing in management intensity in southern Mexico. We also examined spatial distribution of epiphytes with respect to the forest fragment to examine quality of the two agricultural matrix types for epiphyte conservation. We sampled vascular epiphytes in a forest fragment, a shade polyculture farm, and a shade monoculture farm at 100 m, 200 m, and 400 m from the forest. Epiphyte and orchid richness was greater in the forest than in the monoculture but richness was similar in the forest and polyculture farm. Epiphyte species composition differed with habitat type, but not with distance from the forest. In the forest, epiphytes were distributed throughout tree canopies, but in the farms, epiphytes were primarily found on trunks and larger branches. Epiphyte richness and species similarity to forest species declined with distance from the forest fragment in the monoculture, but richness and similarity to forest species did not decline with distance from forest in the polyculture. This suggests polyculture coffee has greater conservation value. In contrast, monoculture coffee is likely a sink habitat for epiphytes dispersing from forests into coffee. Coffee farms differ from forests in terms of the habitat they provide and species composition, thus protecting forest fragments is essential for epiphyte conservation. Nonetheless, in agricultural landscapes, vegetatively complex coffee farms may contribute to conservation of epiphytes more than other agricultural land uses.  相似文献   
70.
针对催化裂化装置待生滑阀突然关闭导致装置停车事故,通过对仪表及系统处理过程进行原因分析,总结了事故的经验教训及防范措施,指出了炼化企业大型设备不但要正确使用,更要精心维护保养,才能确保装置正常平稳运行防患于未然。  相似文献   
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