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161.
"静电-布袋"联合除尘在燃煤电厂的应用前景   总被引:2,自引:2,他引:0  
介绍了我国电除尘器目前面临的主要问题和采取的改造措施及效果,对研究开发"静电-布袋"联合除尘的必要性进行了讨论,并分析、探讨了其主要结构形式、技术特点和应用前景.  相似文献   
162.
为了深入揭示安全生产水平同移动通信技术发展的内在联系,提出安全生产信息技术能力的概念及其监控管理连接、救援响应监测、定位导航追踪3方面子能力的定义,进而通过构建3方面子能力同移动通信主要性能指标之间的关系模型(SPITCMC),并对其进行深入分析和研究。研究结果表明:SPITCMC模型可以准确诠释过去移动通信技术发展对安全生产水平产生的影响,同时可用于预判未来移动通信技术发展对安全生产可能产生的影响程度,从而为后续相关工作的开展提供参考和借鉴。  相似文献   
163.
In this paper, the life span of hydro and nuclear energy generations and the relationship between hydro and nuclear energy generations, environmental pollution, and economic growth were investigated for Japan covering the period of 1960–2018 by employing the Bathtub-Weibull curve and Markov switching-vector error correcting (MSVEC) method, respectively. According to the Bathtub-Weibull curve analysis, a rising failure rate for nuclear energy was found, indicating that the life of nuclear energy has expired, but a decreasing failure rate for hydroelectric energy has been detected. Then two different MSVEC models were used. The MSVEC method, unlike traditional approaches, determines the relationship between variables under different regimes. The results of MSVEC methods indicate three important points. First, regime-dependent asymmetry and regime changes are crucial for policy recommendations. Second, the shocks to hydropower and nuclear energy generations cause temporary deviations from the long-run growth path in both regimes. Lastly, the increase in hydropower generation leads to a decrease in environmental pollution and an increase in GDP, and an increase in nuclear power generation increases pollution and growth in both regimes.  相似文献   
164.
• PAM degradation in thermophilic AD in comparison with mesophilic AD. • PAM degradation and its impact on thermophilic and mesophilic AD. • Enhanced methane yield in presence of PAM during thermophilic and mesophilic AD. • PAM degradation and microbial community analysis in thermophilic and mesophilic AD. Polyacrylamide (PAM) is generally employed in wastewater treatment processes such as sludge dewatering and therefore exists in the sludge. Furthermore, it degrades slowly and can deteriorate methane yield during anaerobic digestion (AD). The impact or fate of PAM in AD under thermophilic conditions is still unclear. This study mainly focuses on PAM degradation and enhanced methane production from PAM-added sludge during 15 days of thermophilic (55°C) AD compared to mesophilic (35°C) AD. Sludge and PAM dose from 10 to 50 g/kg TSS were used. The results showed that PAM degraded by 76% to 78% with acrylamide (AM) content of 0.2 to 3.3 mg/L in thermophilic AD. However, it degraded only 27% to 30% with AM content of 0.5 to 7.2 mg/L in mesophilic AD. The methane yield was almost 230 to 238.4 mL/g VSS on the 8th day in thermophilic AD but was 115.2 to 128.6 mL/g VSS in mesophilic AD. Mechanism investigation revealed that thermophilic AD with continuous stirring not only enhanced PAM degradation but also boosted the organics release from the sludge with added PAM and gave higher methane yield than mesophilic AD.  相似文献   
165.
新疆番茄酱企业生产废水处理利用方式探析   总被引:4,自引:0,他引:4  
近年来,新疆番茄酱加工业得到了迅速发展,目前番茄酱的产销量已占全国的90%以上。与此同时,新疆番茄酱生产企业的废水排放量也大幅增加,大量未经处理的废水直接排放,已对当地的水环境构成严重的污染隐患。本文分析了新疆番茄酱企业生产废水的排放特征与目前排放出路的可行性,并结合新疆的自然地理条件及番茄酱企业的分布情况,着重探讨了土地处理这一适合新疆的废水利用方式,以期有利于新疆的环境保护和废水资源的循环利用。  相似文献   
166.
We conducted a field experiment using constructed communities to test whether species richness contributed to the maintenance of ecosystem processes under fire disturbance. We studied the effects of diversity components (i.e., species richness and species composition) upon productivity, structural traits of vegetation, decomposition rates, and soil nutrients between burnt and unburnt experimental Mediterranean grassland communities. Our results demonstrated that fire and species richness had interactive effects on aboveground biomass production and canopy structure components. Fire increased biomass production of the highest-richness communities. The effects of fire on aboveground biomass production at different levels of species richness were derived from changes in both vertical and horizontal canopy structure of the communities. The most species-rich communities appeared to be more resistant to fire in relation to species-poor ones, due to both compositional and richness effects. Interactive effects of fire and species richness were not important for belowground processes. Decomposition rates increased with species richness, related in part to increased levels of canopy structure traits. Fire increased soil nutrients and long-term decomposition rate. Our results provide evidence that composition within richness levels had often larger effects on the stability of aboveground ecosystem processes in the face of fire disturbance than species richness per se.  相似文献   
167.
有机废水资源化技术--发酵产氢   总被引:1,自引:0,他引:1  
游少鸿  解庆林  马丽丽 《环境技术》2006,24(1):22-25,40
氢作为一种清洁高效的可再生能源日益受到人们的重视.利用有机废水发酵产氢,既保护环境又可获得氢能,是一条符合可持续发展战略的废水资源化途径,极具发展前景.本文介绍了发酵产氢微生物的种类及其产氢机理,对发酵产氢的影响因素进行了分析;总结了有机废水发酵产氢的研究现状,并探讨了今后的研究方向.  相似文献   
168.
中温和高温厌氧生物产氢反应器连续运行的研究   总被引:4,自引:2,他引:2  
采用2个厌氧生物产氢反应器分别在中温(37℃)和高温(55℃)下连续运行.以河底沉积物接种,葡萄糖为基质,在CSTR中成功实现了连续中温厌氧产氢,最高产氢量达8.6L/(L·d),基质产氢摩尔比(H2/葡萄糖)为1.98.以厌氧产甲烷颗粒污泥接种,蔗糖为基质,在UASB反应器中成功实现了连续高温厌氧产氢过程,最高产氢量达6.8L/(L·d),基质产氢摩尔比(H2/蔗糖)为3.6.在高温UASB反应器中培养获得了灰白色的产氢颗粒污泥,平均粒径为0.8~1.2mm,沉速为30~40m/h,电镜观察发现其表层生长大量杆状细菌.对2种产氢污泥的总DNA进行提取和纯化,通过PCR扩增和DGGE分析,发现高温和中温厌氧产氢污泥中的大部分真细菌种类相同,但各自的优势菌种明显不同.  相似文献   
169.
Managing disposal of water produced with petroleum in Kuwait   总被引:1,自引:0,他引:1  
Disposal of water produced with petroleum has been of great interest in Kuwait for the last 20 years. The current problem arose when the Burgan oil field, which is the second largest field in the world, experienced successive increases in the water content of the produced oil. This study introduces a decision-making analysis of the considered alternatives for the disposal of the produced water. Four alternative solutions exist for the industry as practical solutions for the disposal of water produced in Kuwait. The first method utilizes a large number of pits to discharge water. The second alternative depends on discharging water into sealed pits. The third approach to dispose water is by injecting the water underground. The last method is similar to the previous one, but takes into consideration the recovery of reservoir pressure to maintain the rate of oil production. A questionnaire was distributed to 48 experts at the top management level of the petroleum companies and the governmental authority. The data collected considered cost, efficiency, and environmental parameters. Based on the data, a statistical analysis was conducted using the factor analysis method to reduce the number of investigated variables. The analysis concluded that the optimal solution is to use the effluent injection method to discharge water produced with oil in Burgan and similar fields in Kuwait.  相似文献   
170.
城市有机垃圾间歇厌氧消化pH控制动力学研究   总被引:3,自引:0,他引:3  
对厌氧消化系统的物料及电离平衡进行分析,利用底物降解和微生物生长动力学建立城市有机垃圾间歇厌氧消化pH值控制模型,并研制开发了间歇厌氧消化过程pH值与产气量最优化计算机软件.运用该模型可预测不同厌氧消化过程的最佳pH值,从而通过控制厌氧系统的pH值使系统产气量达到最大,通过2组对比实验验证模型的有效性.结果表明,在相同的实验条件下厌氧系统的pH控制在最佳值时系统产气较未对pH值控制时稳定,且总产气量平均提高20%左右.  相似文献   
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