复合喷动塔内蒸发特性的数值模拟与实验研究

分析了描述喷动塔内气液流动、雾化、蒸发、碰壁的数学模型,运用上述模型模拟脱硫塔内蒸发特性,得到了入口介质条件对塔内蒸发特性及液相水含量的影响,通过与实验值比较验证了模型的可靠性。模拟结果表明:液滴蒸发强度呈现先升高后降低趋势,在距离喷嘴300 mm处达到最大值;在一、二级塔体交界处,由于受多级喷动结构影响,液滴蒸发速率明显升高;液滴截面质量流率沿塔体轴向逐渐降低,在1 500 m处基本蒸发完毕;蒸发强度与喷嘴雾化压力呈非单调关系,烟气温度和含湿量对一级塔内液态水含量有3倍~5倍的影响;数值模拟结果与实验值基本一致,可以作为研究塔内液滴蒸发特性的有效工具。     

内循环生物流化床处理石化废水的中试研究

进行了内循环生物流化床处理石化废水的中试研究,当进水平均ＣＯＤ为８００ｍｇ／Ｌ,流化床出水再辅这以气浮后处理,ＣＯＤ可降至２００ｍｇ／Ｌ,当进水ＣＯＤ为５００ｍｇ／Ｌ时,ＣＯＤ可达１００ｍｇ／Ｌ,本试验中的ＣＯＤ去除容积负荷可达１５ｋｇ／（ｍ＾３·ｄ）以上。     

Recovery of Cu(Ⅱ) from aqueous solution by induced crystallization in a long-term operation

The feasibility of copper recovery by induced crystallization in a long period(174 days) was investigated in a seeded fluidized bed reactor(FBR). The process was divided into 3 periods according to different influent conditions, and the period III was separated into III-a and IIIb due to the adjustment of the molar ratio of CO_3~(2-)concentration to copper concentration([CT]/[Cu~(2+)]). The removal efficiency could exceed 95% and the average effluent copper concentration decreased to 3.0 mg/L. The mean particle size of seed grains with copper crystals coating on, raised to 0.36 mm from initial 0.18 mm. During period III-a, the supersaturation exceeded 2.88 × 104, the removal efficiency decreased to 60%–80% and the particle size dropped to 0.30 mm, due to the generation of fines by homogeneous crystallization and seeds breaking. And the morphology of the crystals on the seed grains changed from rod-like to spherical which lead to the particle size decreasing. In period III-b,the supersaturation was modified by adjusting the molar ratio of [CT]/[Cu2+] to 1.2 from 2.The efficiency was back to 95% and the mean particle size grew to 0.36 mm at the end of IIIb, the crystals coating on the seeds turned back to rod-like products of good stability. This study illustrated that the copper salt crystal could keep on growing on the seed grains for over 150 days, the feasibility and controllability of copper recovery by induced crystallization process in FBR were satisfactory, even under the dramatic changes in influent conditions.     

双循环流化床烟气脱硫的试验研究

利用循环流化床烟气脱硫热态试验装置对双循环流化床烟气脱硫工艺进行了中试研究。通过试验的方法研究喷水量、钙硫比和床料浓度等因素对脱硫效率的影响 ,并同单循环流化床烟气脱硫工艺的中试结果进行了对比。试验结果表明 ,喷水量、循环灰物料浓度和钙硫比对脱硫率影响很大。在相同试验工况下 ,双循环流化床烟气脱硫工艺比单循环流化床烟气脱硫工艺的脱硫效率要高     

Resource recovery potential from secondary components of segregated municipal solid wastes

Fermentable components of municipal solid wastes (MSW) such as fruit and vegetable wastes (FVW), leaf litter, paddy straw, cane bagasse, cane trash and paper are generated in large quantities at various pockets of the city. These form potential feedstocks for decentralized biogas plants to be operated in the vicinity. We characterized the fermentation potential of six of the above MSW fractions for their suitability to be converted to biogas and anaerobic compost using the solid-state stratified bed (SSB) process in a laboratory study. FVW and leaf litter (paper mulberry leaves) decomposed almost completely while paddy straw, sugarcane trash, sugarcane bagasse and photocopying paper decomposed to a lower extent. In the SSB process between 50–60% of the biological methane potential (BMP) could be realized. Observations revealed that the SSB process needs to be adapted differently for each of the feedstocks to obtain a higher gas recovery. Bagasse produced the largest fraction of anaerobic compost (fermentation residue) and has the potential for reuse in many ways.     

Invasive species and coal bed methane development in the Powder River Basin, Wyoming

One of the fastest growing areas of natural gas production is coal bed methane (CBM) due to the large monetary returns and increased demand for energy from consumers. The Powder River Basin, Wyoming is one of the most rapidly expanding areas of CBM development with projections of the establishment of up to 50,000 wells. CBM disturbances may make the native ecosystem more susceptible to invasion by non-native species, but there are few studies that have been conducted on the environmental impacts of this type of resource extraction. To evaluate the potential effects of CBM development on native plant species distribution and patterns of non-native plant invasion, 36 modified Forest Inventory and Analysis plots (each comprised of four 168-m² subplots) were established in the Powder River Basin, Wyoming. There were 73 168-m² subplots on control sites; 42 subplots on secondary disturbances; 14 on major surface disturbances; eight on well pads; and seven on sites downslope of CBM wells water discharge points. Native plant species cover ranged from 39.5 ± 2.7% (mean ± 1 SE) in the secondary disturbance subplots to 17.7 ± 7.5% in the pad subplots. Non-native plant species cover ranged from 31.0 ± 8.4% in the discharge areas to 14.7 ± 8.9% in the pad subplots. The control subplots had significantly less non-native species richness than the combined disturbance types. The combined disturbance subplots had significantly greater soil salinity than the control sites. These results suggest that CBM development and associated disturbances may facilitate the establishment of non-native plants. Future research and management decisions should consider the accumulative landscape-scale effects of CBM development on preserving native plant diversity.     

烟气循环流化床脱硫脱硝工艺技术的特点与现状

火力发电厂是我国最主要的烟气排放源,产生大量的SO2及NOx,给大气环境造成了很大的危害.简单阐述了烟气循环流化床脱硫脱硝技术的一些特点,介绍了目前几种常见的循环流化床脱硫脱硝技术.     

气箱脉冲袋除尘器在复合肥冷却床的应用

阐述了气箱脉冲袋除尘器的原理,以及在复合肥冷却床烟气集中处理的技术方案和应用结果.     

表面活性剂废水处理技术的研究现状与问题分析

介绍了表面活性剂废水的特点及危害,概述了处理表面活性剂废水常用的物理法,化学法,生物法等方法,并对各类方法的应用现状和发展方向进行了分析和评价。提出了一种处理LAS废水十分具有前景的新方法——复极性固定床电解法,并提出这一新型的污水处理方法的优缺点及未来需要解决的问题。     

用棉籽油皂脚制备棉籽油甲酯

以002CR型阳离子交换树脂为催化剂,在固定床反应器中用高酸值棉籽油皂脚制备棉籽油甲酯,考察了各种因素对酯化反应的影响。实验结果表明,在甲醇与脂肪酸摩尔比为2、反应温度为60℃、停留时间为80min的条件下,酯化率为94．67％。工业化生产中可选用经脱水处理后的工业甲醇为原料,以降低生产成本。所得棉籽油甲酯的收率为90％,主要性能指标基本达到美国生物柴油标准要求。