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[en] To obtain reliable estimates of the quantities and rates of the gas production in L/ILW a series of measurements was carried in the last 7 years in Hungary. The typical gas production rates were 0.05-0.2 STP litre gas/day for CO2 and CH4 generation, and less for H2. No explosive gas mixture was indicated in the L/ILW drums during the investigated storage period. Compositions of headspace gases in closed L/ILW vaults were in agreement with gas generation processes observed in L/ILW drums. The stable carbon isotope measurements show that the main source of the CO2 gas is the degradation of organic matter and indicates microbial degradation processes as the main sources of CH4. Typical tritium activity concentrations were <10 Bq/l gas in the drums and <1,000 Bq/l gas in the vaults. Typical 14C activity values of the headspace gases were <2.0 Bq/l gas in the drums and <1,000 Bq/l gas in the vaults. (author)
[en] The main function of nuclear power plant safety systems is to prevent damage to the reactor and the release of radioactive materials into the surroundings following an occurrence that interrupts normal power plant operation. Recent nuclear regulations concerning the emergency power generating facilities in nuclear power plants consider diesel engines only for the application which is n't the best choice for stand by generation needs. In this paper the main goal is to determine the main characteristic of Diesel Generator (DG) and Gas Turbine Generator (GTG) and justify the main general requirements for a station blackout power sources using gas turbine generator instead of commonly used diesel generators to bring multiplicity to the design of the nuclear unit
[en] B10F3 gas filled detectors are employed for thermal neutron detection. These were manufactured in ECIL in late 1970's but discontinued due to problems of availability of good quality of enriched B10F3. A new project was taken up on development basis with improved system and methods for gas generation and purification with basic know-how from BARC. The process is run many a time; counters are made and tested satisfactorily with repeatability of characteristics. With a concise description of B10F3 filled counters and summary of the results obtained, this paper presents certain aspects of manufacturing. Tasks ahead to take up bulk manufacturing and the issues for further improvements are brought out. (author)
[en] Present article is devoted to production of producer gas in Tajikistan. Therefore, the scientific aspects and technology of producer gas obtaining from the coals of Fan-Yagnob Coal Deposit were considered. The coal tests results on gas generator were discussed. The dependencies of the rate of coal conversion and composition of synthetic gas on consumption and proportion of air and vapor were defined.
[en] In this study, the thermal/fluid characteristics of gas inside the turbine exhaust heat exchanger of KSLV were analyzed by theoretical prediction and numerical analysis while changing exhausted hot gas to gas generator(G.G.) and steam generator(S.G.) passing through the inside of the heat exchanger. Flow characteristics according to properties of hot gas were confirmed through the analysis results, and the change in the outlet temperature of the cold gas was analyzed. In case of G.G., outlet temperature of cold gas was higher than that of S.G. due to the Cp, μ, k. As flow rate of the cold gas increased, outlet temperature of cold gas decreased and the correction factor from the S.G. to the G.G. increased, but the increase gradually decreased. It is expected that it will be used as a basic data for predicting G.G. conditions from the result of testing heat exchanger with S.G. in the future.
[en] In this work, we developed the first study in Colombia to obtain and evaluate syngas compositions derived from asphaltenes gasification. These asphaltenes came from the implementation of a Deasphalting process to San Fernando crude oil, with the purpose of looking for technological options for their utilization. We performed the design, installation and commissioning of facilities for the gasification of asphaltenes at laboratory scale, it following an experimental methodology, performing nine tests and considering temperature and agent gasification quantity (oxygen) as independent variables. The syngas derived from gasification was analyzed by two chromatographic techniques, which reported the presence of refinery gases and sulfur. We evidenced a growth tendency of CO, H2 and sulfur composition and a decrease in CH4 and CO2 composition with temperature. The composition of the syngas was evaluated with different quantities of gasification agent (33%, 40% and 47% the amount of oxygen theoretically required for complete combustion) at each temperature levels operated. It was established that when using a 40% of gasification agent, you get greater average content of CO and H2, which are the interest gases in the gasification process.
[en] The energy and spectral characteristics of an HF laser operating by using a new method of obtaining the oxidising gas based on a two-region mixing are studied experimentally. The investigation involved redistribution of the overall amount of the rare-gas diluent (helium) delivered to the laser between the gas generator (the first mixing region) and the subsonic parts of the nozzles of the nozzle unit (the second mixing region). In this case, the temperature in the gas generator was maintained constant and the experiments were conducted under conditions when either the mass flow of atomic fluorine or the pressure in the gas generator were maintained constant. It was shown that upon a nearly full transfer of helium from the first mixing region to the second one in the constant-pressure regime in the gas generator, the laser output power increased by 70%, while in the regime of a constant mass flow of atomic fluorine, the output power increased by 14% along with a simultaneous increase in the specific energy extraction by 40%. The lasing region was found to lengthen by no less than 35%. (lasers)
[en] The paper describes the development of a situation concerning identification, recovery and characterisation of a set of radioactive sources. The bio-gas generator from a waste water treatment plant was planned to be demolished. A warning about the level gauges was received by national regulatory body and therefore one triggered the events which led to the sources. Institute for Nuclear Research was charged by the National regulatory body, with tasks for identification, recovery and conditioning of radioactive sources. (author)
[en] Gas generator is the device to produce high enthalpy gases needed to drive turbo-pump system in liquid rocket engine. And, the combustion temperature in gas generator should be controlled below around 1,000K to avoid any possible thermal damages to turbine blade by using either fuel rich combustion or oxidizer rich combustion. Thus, nonequilibrium chemical reaction dominates in fuel-rich combustion of gas generator. Meanwhile, kerosene is a compounded fuel with various types of hydrocarbon elements and difficult to model the chemical kinetics. This study focuses on the prediction of the non-equilibrium reaction of fuel rich kerosene/LOX combustion with detailed kinetics developed by Dagaut using PSR (Perfectly Stirred Reactor) assumption. In Dagaut's surrogate model for kerosene, chemical kinetics of kerosene consists of 1,592 reaction steps with 207 chemical species. Also, droplet evaporation time is taken into account in the PSR calculation by changing the residence time of droplet in the gas generator. Frenklach's soot model was implemented along with detailed kinetics to calculate the gas properties of fuel rich combustion efflux. The results could provide very reliable and accurate numbers in the prediction of combustion gas temperature,species fraction and material properties