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991.
Sureewan Sittijunda Alissara Reungsang Sompong O-thong 《International Journal of Hydrogen Energy》2010,35(24):13427-13434
Poultry slaughterhouse sludge from chicken processing wastewater treatment plant was tested for their suitability as a substrate and inoculum source for fermentation hydrogen production. Dual digestion of poultry slaughterhouse sludge was employed to produce hydrogen by batch anaerobic self-fermentation without any extra-seeds. The sludge (5% TS) was dual digested by aerobic thermophilic digestion at 55 °C with the varying retention time before using as substrate in anaerobic self-fermentation. The best digestion time for enriching hydrogen-producing seeds was 48 h as it completely repressed methanogenic activity and gave the maximum hydrogen yield of 136.9 mL H2/g TS with a hydrogen production rate of 2.56 mL H2/L/h. The hydrogen production of treated sludge at 48 h (136.9 mL H2/g TS) was 15 times higher than that of the raw sludge (8.83 mL H2/g TS). With this fermentation process, tCOD value in the activated sludge could be reduced up to 30%. 相似文献
992.
Dual throat nozzle (DTN) is fast becoming a popular technique for thrust vectoring. The DTN is designed with two throats, an upstream minimum and a downstream minimum at the nozzle exit, with a cavity in between the upstream throat and exit. In the present study, a computational work has been carried out to analyze the performance of a dual throat nozzle at various mass flow rates of secondary flow and nozzle pressure ratios (NPR). Two-dimensional, steady, compressible Navier-Stokes equations were solved using a fully implicit finite volume scheme. The present computational results were validated with available experimental data. Based on the present results, the control effectiveness of thrust-vectoring is discussed in terms of the thrust coefficient and the coefficient of discharge. 相似文献
993.
CO2 can be converted to useful fuels by electrochemical processes. As an effective strategy to address greenhouse effect and energy storage shortage, electrochemical reduction of CO2 still needs major improvements on its efficiency and reactivity. Microfluidics provides the possibility to enhance the electrochemical performance, but few studies have focused on the virtual interface. This work demonstrates a dual electrolyte microfluidic reactor (DEMR) that improves the thermodynamic property and raises the electrochemical performance based on a laminar flow membrane-less architecture. Freed from hindrances of a membrane structure and thermodynamic limitations, DEMR could bring in 6 times higher reactivity and draws electrode potentials closer to the equilibrium status (corresponded to less electrode overpotentials). The cathode potential was reduced from −2.1 V to −0.82 V and the anode potential dropped from 1.7 V to 1 V. During the conversion of CO2, the peak Faradaic and energetic efficiencies were recorded as high as 95.6% at 143 mA/cm2 and 48.5% at 62 mA/cm2, respectively, and hence, facilitating future potential for larger-scale applications. 相似文献
994.
Renewable energy resources, such as wind, are available worldwide. Locating areas with high and continual wind sources are crucial in pre-planning of wind farms. Vast offshore areas are characterized by higher and more reliable wind resources in comparison with continental areas. However, offshore wind energy production is in a quite preliminary phase. Elaborating the potential productivity of wind farms over such areas is challenging due to sparse in situ observations. The Mediterranean basin is not an exception. In this study we are proposing numerical simulations of near-surface wind fields from regional climate models (RCMs) in order to obtain and fill the gaps in observations over the Mediterranean basin. Four simulations produced with two regional climate models are examined here. Remote sensing observations (QuikSCAT satellite) are used to assess the skill of the simulated fields. A technique for estimating the potential energy from the wind fields over the region is introduced. The wind energy potential atlas and the map of a wind turbine's functional range are presented, locating the potentially interesting sub-regions for wind farms. The ability of models to reproduce the annual cycle and the probability density function of wind speed anomalies are detailed for specified sub-regions. 相似文献
995.
996.
《International Journal of Hydrogen Energy》2021,46(70):34924-34957
Consumers conventionally adopt diesel generation to meet the energy needs where the grid connection is unreliable or unavailable. While electrification has provided these communities a variety of economic and social opportunities, diesel consumption has resulted in adverse costs and environmental pollution. Two technologies available to reduce the expense and emissions of diesel fuel reliance include dual fuel or hybrid diesel applications. The dual-fuel approach involves a supplementary gas fuel charge in support of reduced diesel fuel consumption. Hybrid applications involve the integration of renewable generation to displace diesel fuel consumption. This paper reviews the potential for hybrid dual-fuel applications, identifying engine flexibility as a major integration barrier. In comparing the flexibility of various dual-fuel technologies to operate dynamically, this paper presents a critical review across hydrogen, liquified petroleum gas (LPG), natural gas (NG) and blended hydrogen and NG derivatives. The results identify a range of approaches able to improve engine flexibility and thus reduce the cost and carbon intensity of diesel-fired internal combustion engines. At low load conditions, while NG and LPG exhibit similar performance, the use of hydrogen and hydrogen blends provide improved engine performance and response. Unfortunately, given the current cost of hydrogen fuel, significant commercial barriers exist to the adoption of hydrogen or hydrogen blended fuels. Despite this, this review indicates the potential of hydrogen-NG blends to offer additional flexibility in comparison to alternative dual-fuel technologies. This position is furthered considering near term cost targets associated with the development of a global green hydrogen industry, coupled with its ability to serve as a demand-side management approach within isolated power systems, one of the multiple future research themes. 相似文献
997.
This paper aims at studying the effect of hydrogen induction on engine performance, emission and combustion behaviour of a diesel engine fuelled with the emulsion of used palm oil (called as WCO-waste cooking oil) as pilot fuel and hydrogen as primary fuel. A single cylinder water-cooled direct injection diesel engine was tested at 100% and 40% loads. Results were compared with neat diesel, neat WCO and WCO emulsion at both loads in single fuel operation. WCO emulsion in single fuel mode indicated improvement in performance and reduction in all emissions as compared to neat WCO. Dual fuel operation with hydrogen induction further reduced the emissions of smoke HC and CO with WCO as pilot fuel at all power outputs. However, hydrogen induction resulted in reduced thermal efficiency at 40% load. WCO emulsion showed higher ignition delay as compared to neat WCO. Dual fuel operation with hydrogen induction increased the ignition delay further. Heat release pattern showed higher premixed combustion rate with hydrogen induction mainly at high power outputs. Premixed combustion rate became very high at higher rates of hydrogen admission mainly at high power output. In general, hydrogen induction showed superior performance at high power output and inferior performance at low power output with WCO emulsion as injected fuel. 相似文献
998.
Dual chamber microbial fuel cell reactors were inoculated with a mixed culture of sulfate-reducing bacteria with anode potential being the controlling parameter. A negative poised anode potential enhanced the performance of this fuel cell while a positive poised anode potential had adverse effects on cell performance. Negative anodic potential affects the biofilm characteristics, as evidenced by electrochemical analysis. Microbial community was changed accordingly. 相似文献
999.
通过对GPS RTK技术工作特点的分析,结合在山林中使用GPS RTK作业时遇到的卫星信号和数据链问题,提出一些解决方法,在一定程度上解决了山林中RTK测量的难题。 相似文献
1000.