China
Africa
Explore chapters and articles related to this topic
Design of Downdraft Biomass Gasifier Systems and Naturally Aspirated Producer Gas Burners
Published in Debi Prasad Mishra, Advances in Combustion Technology, 2023
ABETS [13] re-designed the hearth as a continuously converging section, without a throat (see Figure 6.1). The material selection was also made so that the part of the hearth in direct contact with the highest temperatures—viz., the inner surface of the hearth and the tuyere tubes—could have a long enough life to justify major maintenance, and could be easily repaired or replaced. They chose ceramic tiles with more than 90% alumina content for the walls, and a special ceramic material for nozzle tubes. Tiles or tubes that look damaged during major maintenance can be replaced easily. ABETS [13] also recommends that the lower part consisting of the hearth of the gasifier be constructed using firebricks and ceramic tiles inside, and housed in a metallic outer container. The upper part comprising the fuel container could be separately fabricated and bolted with sealing to the lower part during assembly.
Hypersonic Aircraft
Published in G. Daniel Brewer, Hydrogen Aircraft Technology, 2017
Recycled supercharged ejector mode — This mode utilizes fan-supercharged ejector rocket operation with full afterburning to provide high thrust at an intermediate level of specific impulse. The ejector rocket subsystem operates on liquid air (LAIR) as oxidizer. The LAIR is obtained using as heat sink the cryogenic hydrogen which is tanked on board the vehicle in the form of slush (50% liquid/solid mixture). That portion of the partially warmed up hydrogen from the heat exchanger unit which is not used as fuel in the rocket operation is recycled to the subcooled hydrogen in the vehicle tank. When the bulk temperature of the tanked hydrogen is raised to about -423°F, the air liquefaction process is terminated. In addition to the augmented low temperature refrigerative effect, the use of slush-form hydrogen increases fuel density about 16 to 18%, thus reducing fuel container volume and weight. The recycled supercharged ejector mode is used for takeoff and acceleration to about Mach 2.5 flight speed, the cutoff velocity being limited by the availability of supercooled hydrogen.
Ethanol
Published in Arumugam S. Ramadhas, Alternative Fuels for Transportation, 2016
Alan C. Hansen, Carroll E. Goering, Arumugam Sakunthalai Ramadhas
The microemulsion fuel was comparatively tested in a Ford three-cylinder, DI, CI engine equipped with a distributor-type injection pump. Compared to No. 2 diesel, the microemulsion fuel produced lower exhaust temperatures and 4–5% higher brake thermal efficiency. The microemulsion fuel also reduced exhaust smoke and CO emissions, but increased the level of unburned hydrocarbons. A concern for fuel safety led Boruff et.al. (1982) to develop Figure 5.18. In a closed fuel container, either for fuel storage or on a vehicle, the flammability of the gases above the liquid is a concern. Over a range of typical environmental temperatures, the mixture above either No. 1 or No. 2 diesel is usually too lean to burn if ignited. The mixture above gasoline is usually too rich to burn. However, the fuels containing ethanol or butanol are flammable at common environmental temperatures and therefore must be handled with caution.
A review of the current status and development of 5GDHC and characterization of a novel shared energy system
Published in Science and Technology for the Built Environment, 2022
Jonas Lindhe, Saqib Javed, Dennis Johansson, Hans Bagge
Local solutions adapt the temperature to the individual building and require a more refined energy source, for example, electrical heating, gas, or wood pellets. The local equipment, such as a boiler, is not as advanced or efficient as the centralized solutions. Local solutions normally lack equipment for exhaust treatment but have no distribution losses. They also require more attention from the customer compared to centralized solutions. The unit and any support equipment (e.g., chimney, fuel container) occupy space in the building and necessitate a higher capacity of electrical power, gas, or other types of fuel supplied to the place of use. Thus, even though the local solutions do not require a grid for transporting thermal energy from the production unit to the customer, their use increases the cost of operating, maintaining, and developing the electricity and gas grids.
Case study on phytoremediation driven energy crop production using Sida hermaphrodita
Published in International Journal of Phytoremediation, 2018
M. Pogrzeba, J. Krzyżak, S. Rusinowski, S. Werle, A. Hebner, A. Milandru
The gasification experiment was conducted using a fixed-bed gasification facility, as illustrated in Figure S1 (Werle and Wilk 2011). The main component of the lab-scale installation was a well-insulated stainless steel reactor (gasifier) with an internal diameter of 150 mm and total height of 300 mm. Biomass from the fuel container was fed into the top of the gasifier. The gasification air was directed from the bottom by a pressure fan. The HMC biomass was then circulated in a counter current direction to the process gases. In the drying zone, water was evaporated from the fuel. In the second zone (pyrolysis), the biomass was thermally decomposed into volatiles and solid char. In the third zone, carbon was converted into the main combustible components of syngas. In the last zone, the remaining char was combusted. The combustion zone provided a source of energy for the gasification reactions in the upper zones. The gasification reactions are mainly endothermic. The internal reactor temperature was measured by six N-type thermoelements located along the vertical axis of the reactor integrated with an Agilent temperature recording system. The syngas was transported from the gasifier and then cleaned by a cyclone, scrubber and drop separator. Gas was burnt in the burner and the flue gases were lead into the chimney equipped with a filter integrated with the particle separator. The volumetric fractions of the main syngas components were measured online using a Fisher Rosemount and ABB integrated set of analysers.
Corrosion of copper-coated used nuclear fuel containers due to oxygen trapped in a Canadian deep geological repository
Published in Corrosion Engineering, Science and Technology, 2018
David S. Hall, Thalia E. Standish, Mehran Behazin, Peter G. Keech
The Nuclear Waste Management Organization (NWMO) is evaluating the feasibility and long-term safety of a deep geological repository (DGR) for the passive and permanent disposal of Canada’s spent nuclear fuel. A key component of the DGR concept is a copper-coated used fuel container (UFC), designed to keep high-level nuclear waste isolated from the environment for many thousands of years [1,2]. An important consideration is the maximum possible depth of corrosion, by various processes, into the copper coating on the UFCs. It is by now established that following closure of a DGR, the conditions will evolve from an initial warm oxic period to a long-term cool, anoxic period [3–7]. The maximum depth of copper corrosion during the early oxic stage, which is the focus of this article, may be evaluated from the quantity of O2 that will be trapped when the DGR is sealed closed [8].