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201.
徐剑  倪建东  黄中子 《环境工程》2012,30(2):54-57,123
结合工程实例,从除尘器入口烟气降温、除尘器设备本体、引风机三个方面提出了大型钢铁企业火电机组电除尘系统的改造思路,根据对改造后近两年多运行情况的调研,以实际效果验证了改造的成功,为大型钢铁企业类似自备火电机组的电除尘系统改造提供了借鉴。  相似文献   
202.
方一丰 《环境工程》2012,30(4):70-72,100
某卷烟厂根据"十一五规划"进行异地扩建,重新建设一套异味气体污染治理工程。针对车间排风量大和异味气体释放点源多特点,采取治理工艺各有不同,既达到相应处理效果又节省投资;采用注入式低温等离子体工艺强化对异味气体处理,解决了设备受污染和大风量异味气体难处理等问题,成为整套治理工艺的特色。  相似文献   
203.
Abstract

Two commercial formulations of Bacillus thuringiensis var. kurstaki (BTK), Foray® 48B and Thuricide® 48LV, were applied aerially over nine spray blocks in a hardwood forest in West Virginia in 1991. Droplet spectra and spray mass deposits were determined using water‐sensitive paper strips (WSPS), glass micro‐fiber filters (GMFFs), glass plates and castor oil. Mass deposits of BTK were also assessed on natural foliage by two bioassay methods, i.e., feeding of homogenized foliage containing a starch‐sucrose solution and force‐feeding bioassay of foliar extracts containing re‐dissolved protein precipitate. Deposits on canopy foliage and ground samplers were also assessed by total protein assay and enzyme‐linked immunosorbent assay (ELISA). Droplet spectra on the WSPS were different from those on castor oil. Droplets on horizontal ground WSPS were larger than those on vertical ground WSPS. WSPS placed at canopy level collected more droplets than those at ground level. The total protein deposits (ng/cm2) were consistently higher on all blocks than the delta‐endotoxin protein deposits. Spray mass recovery on the ground samplers were low, and ranged from 2.9 to 8.0% of the applied rates.  相似文献   
204.
Abstract

Spray drops were counted and sized on Kromekote® cards at ground level, and on spruce foliage at canopy level, after aerial application of a formulation containing a microencapsulation medium, over a spruce forest in Ontario. The majority of drops (70%) on foliage was 20 ‐ 75 µm range. A coarse drop size spectrum was observed on cards with a maximum diameter (Dmax) of 380 µm, and with 85% of the drops = 130 µm in diameter. Foliar drop analysis, on the other hand, indicated a finer spectrum with a Dmax of 150 µm, and with 85% of the drops = 75 µm. These results were explained on the basis of formulation ingredients, atomizer setting, weather factors, and drop retention on target surfaces. The assessment of spray deposits on glass plates at ground level indicated that about 16% of the applied spray volume reached the forest floor, a value which is comparable to those obtained in previous forestry applications using the ultra‐low‐volume (ULV) technique.  相似文献   
205.
Background, aim and scope  One of the problems to affect Portland cement matrices is low resistance to aggressive agents, due principally to the presence of a high content of portlandite in the hydrated cements. Pozzolanic materials have played an important role in the improving the durability of cement-based materials for decades. This work studies the behaviour of cement mortar matrices blended with 10% calcined paper sludge (source for metakaolinite) and exposed to different environmental conditions (saline and non-saline environments) after 6 and 12 months of exposure. Materials and methods  Two cements were studied: an ordinary Portland cement (CEM 1, 42.5R), acting as reference cement, and a blended cement formulated by mixing 90% (by mass) of CEM 1, 42.5R with 10% (by mass) of paper sludge calcined at 700°C for 2 h. The specimens were exposed 1 year to saline and non-saline environments. All the mineralogy samples were studied through X-ray diffraction and scanning electron microscopy (SEM) equipped with an energy dispersive X-ray analyser. The in-depth study on ionic mobility was performed on samples subjected to natural exposure (coast and tableland) for 6 and 12 months. Results  Portland cement was composed of quartz, calcite, calcium hydroxide and tobermorite gels. The pozzolanic cement (10% calcined paper sludge) is of the same composition but a high calcite concentration and barium carbonate. SEM analysis from coastline show deposits of variable composition. The deposits are identified on the surface of different mineral components. The minerals from tableland are much fractured, i.e. calcite and feldspars. Inside the fractures, the deposits and the ions are located and trapped superficially. Discussion  SEM analysis of control cement Portland and 10% calcined paper sludge shows deposits on quartz and calcite with a very high concentration of Pb, Zn, Cl and barium sulphate. A very porous aspect is due to the presence of the different aggregate types. This porous configuration permits retention of the ion environment. The pozzolanic cement in environments subject to the saline mist favours the retention and transport of ions observed. Something similar also happens with the increase in exposure to outdoor weather. Non-saline samples show temperature changes (ice or thaw cycles). Barium retention is kept on the surface in fracture lines by the gelification processes. In general, it may be inferred that an increase in exposure time increases the diffusion of ions towards test piece interiors. The chemical composition profiles show that the ions present different penetration speeds. Conclusions  The results indicate the better vulnerability of pozzolanic cements from calcined paper sludge in saline and non-saline environments. The cements with a 10% addition of calcined paper sludge favour retention and transport of ion has been observed. Recommendations and perspectives  Today, projects are centred on a new recycling line for industrial waste of this kind, with special attention on its incorporation in cement manufacture as a pozzolanic material, setting the most appropriate activation conditions of the mineralogical compound in this waste (kaolinite and metakaolinite) and taking them as a starting point for this project. The use of pozzolanic cement with 10% addition of calcined paper sludge is a system which favours ionic retention.  相似文献   
206.
以新疆天山水泥股份有限公司一分厂1水泥磨除尘系统技术改造为实例,阐述了获1993年国家环保最佳实用技术推广的LCPM型高压离线侧喷脉冲袋除尘器在水泥磨系统的应用及产生的效果。  相似文献   
207.
Abstract

Dipel® 8AF, a commercial formulation of Bacillus thuringiensis (B.t.) was sprayed undiluted at 30 BIU in 1.8L/ha over a block B1, and sprayed after dilution with water at 30 BIU in 6.2 L/ha over another block B2 in an oak forest infested with the gypsy moth (Lymantria dispar L.) in southeastern Ontario, Canada. Spray was applied in May 1987 using a Cessna 188 Agtruck aircraft equipped with four Hicronair® AU4000 atomizers. Droplet sizes were measured at mid‐canopy level of oak trees and at ground level using cylindrical Kromekote® cards. Deposit per unit area was assessed on aluminum oak leaves.

At the lower volume rate of 1.8 L/ha, spray droplets were smaller and droplets/cm2 were lower on the cylindrical Kromekote cards in B1 than those obtained in B2 which received the higher volume rate of 6.2 L/ha. The average deposit per unit area of the aluminum oak leaves, expressed in nL of the spray volume per cm2 surface area, was also correspondingly lower in B1 than in B2. This was attributed to the higher volume rate of spray application used in B2 than in B1, which resulted in larger droplets and a greater volume deposit/cm2 in B2.  相似文献   
208.
生物滴滤-生物过滤组合工艺处理汽车喷漆废气中试研究   总被引:3,自引:1,他引:2  
采用中试规模的生物滴滤-生物过滤组合工艺设备处理某汽车厂喷漆车间废气,研究了组合式反应器对废气的净化效果和2处理单元对污染组分的去除能力及微生物特性.该汽车厂喷漆车间废气中的主要组分为甲苯、二甲苯、乙酸乙酯、乙酸丁酯、丁醇、丙酮和甲基丙基甲酮.组合式反应器对废气中的污染物有较好的处理效果,但不同的污染组分在不同处理单元...  相似文献   
209.
建立了不同雾化粒度下雾滴传热传质特性的理论计算模型,其计算结果能与实验喷雾干燥脱硫塔上所得数据较好地吻合。所得的雾滴干燥曲线和吸收曲线有助于了解雾滴在塔内的干燥。反应过程,从而指导工业装置设计和操作的改进。  相似文献   
210.
针对目前现有的用上、下喷淋的方式进行废气除尘处理技术的不足,提出了横向喷雾的理论和方法,该技术除保留和强化了水滴二次细化技术外,更避免了喷淋孔口易堵塞从而造成净化效果降低的技术问题,也使得对于喷淋孔口尺寸的设计变得更容易把握,更易规格化。同时,采用化学添加剂按一定比例将化学降尘剂注入喷雾水中,改善水溶液对粉尘的湿润能力,从而提高喷雾降尘效率。该技术的除尘净化效率高,运行可靠性强,综合性能好。  相似文献   
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