Production of soybean ethanol-based biodiesel using CaO heterogeneous catalysts promoted by Zn,K and Mg

This article focuses on the optimization of the production of fatty acid ethyl esters from soybean oil using CaO-based heterogeneous catalysts. Three different catalytic promoters were evaluated: Magnesium, zinc, and potassium. The reaction has evaluated the promoter content (promoter to calcium molar ratio), catalyst load, alcohol to oil molar ratio, and temperature. Response surface methodology (RSM) was used to evaluate the influence of each variable on the yield of biodiesel. The addition of K₂O or MgO in the catalyst has enhanced the yield in fatty acid ethyl esters, while the use of ZnO as a promoter was not successful.     

The determination and matching analysis of pinch point temperature difference in evaporator and condenser of organic rankine cycle for mixed working fluid

Exergo-economic analysis of the pinch point temperature difference (PPTD) in both evaporator and condenser of sub-critical organic Rankine cycle system (ORCs) are performed based on the first and second laws of thermodynamics. Taking mixture R13I1/R601a as a working fluid and the annual total cost per net output power Z as exergo-economic performance evaluation criterion, the effects of PPTD in evaporator ΔT_e, and the PPTD ratio of condenser to evaporator y, on the exergo-economic performance of ORCs are analyzed. Moreover, how some other parameters influence the optimal PPTD in evaporator ΔT_e,opt and the optimal PPTD ratio of condenser to evaporator y_opt are also discussed. It has been found that the exergo-economic performance of ORCs is remarkably influenced by ΔT_e and y, and there exists ΔT_e,opt and y_opt. In addition, ΔT_e,opt and y_opt are affected by heat transfer coefficient ratio of condenser to evaporator ß, the temperature of working fluid at dew point in condenser T_1a, and composition of R13I1/R601a: larger ß and T_1a lead to lower ΔT_e,opt and y_opt; by contraries, larger mass fraction of R13I1 makes ΔT_e,opt and y_opt increase, and y_opt increases linearly. The effects of the temperature of working fluid at bubble point in evaporator T_3a, mass flow rate of exhaust flue gas m_g, and inlet temperature of exhaust flue gas T_gi on ΔT_e,opt and y_opt are very slight. For comparison, three additional working fluids, namely R601a, R245fa, and 0.32R245fa/0.68R601a, are also taken into account.     

Experimental investigation of a 250-kW turbine organic Rankine cycle system for low-grade waste heat recovery

An organic Rankine cycle (ORC) is generally used for converting low-grade heat into electricity. In this study, an extensive literature survey was conducted to identify current research gaps on experimental ORC systems. Specifically, there is limited experimental data and limited details on thermal and expander efficiencies of ORC systems. In order to address these gaps, the objective of this study included developing a turbine ORC with a power output exceeding 50 kW and thermal efficiency exceeding 8% for a heat source temperature < 120°C. The experimental results indicated that the system achieved a net power output of 242.5 kW and a thermal efficiency of 8.3% (the highest value for a turbine ORC system for the heat source temperature below 120°C). Thus, the study addressed the gaps identified in the research area of ORCs.     

The effect of industry activities on public support for ‘fracking’

Research suggests that previous, current, and prospective extractive industry activities influence perceptions of new development. Studies that have drawn this conclusion, however, have usually focused on specific projects in specific communities. Here, these factors are examined on an aggregate, national scale. Combining geospatial data on extractive industry activities and survey data from a nationally representative sample (N = 1061), the influence of extractive industry activities on support for fracking is studied. While limited evidence is found for the impact of proximity to oil and gas wells or production on support for fracking, employment levels in the natural resources and mining sector in the respondent’s county and residence in an area experiencing active oil and gas development significantly increase support for fracking. The results highlight the role of spatial and community factors in shaping support for energy development.     

Comparative study on effect of blending,thermal barrier coating (LHR) and injector nozzle geometry on biodiesel-fuelled engines

Increased petroleum prices, increased threat to the environment from exhaust emissions and global warming have generated intense international interest in developing renewable and alternative non-petroleum fuels for internal combustion engines. Evolving suitable technology for addressing energy crisis creates a continued investigation into the search for sustainable and clean-burning renewable fuels. This work investigates suitability of different non-edible-derived biodiesels such as cotton seed oil methyl ester (COME), Honne oil methyl ester (HnOME) and Rubber seed oil methyl ester (RuOME) to four stroke, single cylinder compression ignition (CI) engine. Engine tests were conducted to study the effect of fuel blending, thermal barrier coating (TBC) or Low Heat Rejection (LHR) and injector nozzle geometry on the performance, combustion and emission characteristics of COME, HnOME and RuOME in the modified CI engine. Blends of biodiesels with diesel were varied from 20 to 80% in steps of 20%. Two thermal barrier coatings of partially stabilized zirconium (PSZ) and aluminium oxide (Al₂O₃) were provided on the engine to make it fully adiabatic. Nozzle injectors of 3, 4 and 5 holes, with size of orifice varied from 0.2 to 0.3 mm size were selected for the study. It was concluded that B20 biodiesel blend, PSZ-coated engine and four hole nozzle injector of 0.2 mm size resulted in overall better engine performance with increased brake thermal efficiency (BTE) and reduced HC, CO, smoke emissions for the fuel combinations tested. Combustion analysis to study the effect of biodiesel blends, LHR coatings, injector nozzle geometry on the performance of the biodiesel-fuelled engine has been presented to give more insight into the behaviour of operation.     

GC/MS法测定润滑油基础油中多环芳烃

对润滑油基础油中多环芳烃的气相色谱/质谱(GC/MS)测定方法进行了研究,探讨了样品的提取,固相萃取柱净化等前处理方法,同时也对仪器测定条件进行了优化.结果表明,在检测润滑油基础油中多环芳烃时,经优化的GC/MS法的加标回收率和精密度均达到较满意的水平.     

Don’t Fight the Site: Three Geomorphic Considerations in Catchment-Scale River Rehabilitation Planning

Three geomorphic considerations that underpin the design and implementation of realistic and strategic river conservation and rehabilitation programs that work with the nature are outlined. First, the importance of appreciating the inherent diversity of river forms and processes is discussed. Second, river dynamics are appraised, framing the contemporary behavioral regime of a reach in relation to system evolution to explain changes to river character and behavior over time. Third, the trajectory of a reach is framed in relation to downstream patterns of river types, analyzing landscape connectivity at the catchment scale to interpret geomorphic river recovery potential. The application of these principles is demonstrated using extensive catchment-scale analyses of geomorphic river responses to human disturbance in the Bega and Upper Hunter catchments in southeastern Australia. Differing implications for reach- and catchment-scale rehabilitation planning prompt the imperative that management practices work with nature rather than strive to ‘fight the site.’     

低压稳流过滤器的研制及在油田污水处理中的应用

为了解决大庆油田现有核桃壳、石英砂过滤器反冲洗憋压、跑料和滤料再生困难等问题,在对原有过滤装置分析的基础上,根据反冲洗特性,对过滤器进行了改造,开发出低压稳流核桃壳过滤器和低压稳流石英砂过滤器。经现场测试,核桃壳过滤器反冲洗压力由原来的0.15～0.5 MPa降低到0.03～0.08 MPa,石英砂过滤器反冲洗压力由原来的0.27～0.46 MPa降低到0.17～0.20 MPa,且均能实现罐群水反冲洗。改造后核桃壳过滤器出水油平均含量13.4 mg/L,平均去除率为78.1%;出水悬浮物平均含量20.5 mg/L,平均去除率为55%。改造后石英砂过滤器出水油平均含量5 mg/L以下,平均去除率达到75%以上;出水悬浮物平均含量为9.8 mg/L,去除率达到80%以上。为了进一步提高过滤效果,在二级滤前投加絮凝剂形成微絮凝过滤工艺,出水悬浮物可达到3 mg/L,通过两级过滤达到特低渗透地层回注水标准。     

液-固流化床回收印刷线路板中金属的研究

根据废弃印刷线路板中材料密度不同,采用水介质流化床对印刷线路板粉末中的金属进行回收,对0.25～0.177、0.177～0.104、0.104～0.074和-0.074 mm 4个粒级范围内的物料进行分选试验。试验结果表明,在上述4个粒级范围内,随介质流速的增大,金属回收率降低;金属回收率η与实际操作速度（ua）和颗粒终端沉降速度（ut）的比值φ（ua/ut）存在一定线性关系,分析模拟了η与φ之间的相关性方程,外推试验的结果证明了相关性方程的可靠性;在合适的操作条件下,各粒级范围内金属的回收率分别为95.02%、90.07%、87.5%和92.68%。     

三级串联人工快渗系统处理养殖废水

人工快速渗滤系统（constructed rapid infiltration,CRI）是在传统的污水快速渗透系统上发展起来的一种新的生物处理方法。采用猪粪浸泡污水模拟实际猪场处理系统的厌氧出水,研究三级串联人工快渗系统对其污染物的去除效果。试验结果表明,三级串联系统对废水COD、NH3N的去除率稳定在81%和94.5%,出水均满足了《畜禽养殖行业污染物排放标准》（GB18596-2001）的要求,同时三级串联系统还可以有效预防系统的堵塞。