• Transactions of the Korean hydrogen and new energy society
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• v.27 no.2
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• pp.192-200
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• 2016

A characteristics of microwave drying-gasification was analyzed for converting a dewatered sewage sludge generated a wastewater treatment plant. Gas (60%) was the largest component of the product of microwave gasification, followed by sludge char (33%) and tar (2%). The main components of the producer gas were hydrogen (33%) and carbon monoxide (40%), and there was some methane and hydrocarbons ($C_2H_4$, $C_2H_6$, $C_3H_8$). Larger nitrogen and smaller oxygen amounts were generated. Gravimetric tar generated $414g/m^3$. This means a total tar which is a heavy hydrocarbons from the volatile organic substance in the sewage sludge. Selected light tars were benzene, anthracene, naphthalene, pyrene, showing lower concentrations as 2.62, 0.37, 0.49, $0.28g/m^3$, respectively. Sludge char has larger meso pores which is a mean pore size of $50.85{\AA}$ and has high adsorptivity. An amount of adsorption was $228.71cm^3/g$, showing higher quantity than acommercial adsorbers. This indicates that the gas obtained from the microwave gasification of wet sewage sludge can be used as fuel, but the heavy tar in the gas must be treated. Sludge char can be used as a tar reduction adsorbent in the process, and then burns as a solid fuel.

• Advances in Energy Research
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• v.4 no.3
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• pp.223-237
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• 2016

The excess use of conventional sources of energy by the industries and power sector result in acute shortage of energy produced by fossil fuel. To overcome this energy crisis, biomass feedstock is used to produce syngas or producer gas. For cleaning the dust particle present in the producer gas cyclone separators are largely used. In this paper we investigate the performance parameters of cyclone separator mainly efficiency and pressure drop for different feedstock. Cyclone performance has been evaluated based on experimentation and empirical approach using Leith and Licht model. The same has also been calculated by using turbulent RSM in Ansys Fluent for Wood and Coconut shell feedstock. Experimental results show that using feed stock with 10 % Calcium oxide (CaO) by weight, the efficiency of cyclone got reduced from 71.87% to 70.75% for wood feed stock, whereas in case of coconut shell, the cyclone efficiency got reduced from 78% to 73.44%. It is also seen that Leith and Licht model and Reynolds stress model (RMS) predicts very close to the particle collection efficiency evaluated by using experimental data.

• Journal of The Korean Society of Agricultural Engineers
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• v.64 no.5
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• pp.1-8
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• 2022

Hydrogen can be produced by gasification of biomass and other combustible fuels. Depending on oxydant agents, syngas or producer gas compositions become quite different. Since biomass has limited amount of hydrogen including moisture in it, the hydrogen concentration in the syngas is about 15% when air is supplied for oxidant agent. Experiments were conducted to investigate the channges in hydrogen concentrations in syngas with different oxidant agent conditions, fuel conditions, and external heat supply. Allothermal reaction resulted in higher concentrations of hydrogen with the supply of steam over air, reaching over 60%. Hydrogen is produced by water-gas and water-gas shift reactions. These reactions are endothermic and require enough heat. Autothermal reaction occurred in the downdraft gasifier used in the experiment did not provide enough heat in the reactions for hydrogen production. Steam seems a more desirable oxidant agent in producing the syngas with higher concentrations of hydrogen from biomass gasifications since nitrogen is included in syngas when air is used.

• Proceedings of the KIPE Conference
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• 2002.07a
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• pp.225-227
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• 2002

Recently, there are many researches in several places for a new resource, ahead. Also, Water of $70\%$ in the earth it is interested and studied by around world. Long ago, in the side processing-use, it is making study the welding of Hydrogen- oxygen Gas, which is burned to acquired it(hydrogen+oxygen) by electric-disintegration into water, which has perfect-burning rather than exhaust carbon and it has excellent-sides in financials and efficiencies than existing-gas welding by sparking-characteristics of Hydrogen Oxygen gas. Therefore, with constant current source, it is intended to make a producing gas ratio through designing and making for the use of SCR rectifier of existing-formula and then in this paper it hopefully is coming up to characteristics of welding machine and producer of hydrogen oxygen gas with current-controlled type.

• Journal of the Korean Chemical Society
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• v.4 no.1
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• pp.78-80
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• 1957

Up to now, only superficial studies on the combustion velocity of smokeless fuels have been reported, while it should be a basical factor on the utilization of low quality coals and some other smokeless solid fuels. It was, therefore, difficult to choose raw material coals in manufacturing gaseous fuels. With the intent to solve above problem, we have determined combustion velocity of domestic anthracites, graphites, coalites of lignite and cokes from Japanese bituminous coal. The results show that the cokes from Japanese bituminous coal which has been used as raw material in the manufacturing gaseous fuels such as water gas, or producer gas in Korea can be replaced by some sources of domestic anthracite or coalite of lignite.

• Journal of The Korean Society of Agricultural Engineers
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• v.50 no.4
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• pp.51-58
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• 2008

Unit costs for energy production in bioenergy facilities are dependent upon both fixed cost for facility construction and operational costs including biomass feedstock supply. With the increase of capacity, unit fixed cost could be decreased while supply cost tends to increase due to the longer transportation distance. It is desirable to take into account biomass availability in planning bioenergy facilities. A cumulative curve relationship was proposed to relate biomass availability and cumulative products of biomass amount and transportation distance. Optimum size of gasification facilities was affected by collection cost, biomass cumulative relationship. Based on biomass availability of Icheon-City, optimum sizes were about $400kW_{th}$ for gas production, and about $200kW_{el}$ for power generation. Unit cost of bioenergy production could be substantially reduced by reducing collection cost through supplying biomass from diverse sources including land development areas where significant amount of waste wood is generated. When planning bioenergy facilities, however, biomass availability and spatial distribution are key factors in determining the size of capacity.

• Journal of The Korean Society of Agricultural Engineers
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• v.50 no.4
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• pp.89-97
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• 2008

A downdraft gasifier was manufactured for biomass gasification. The gasifier was designed based on the principles of gasification presented in previous studies. The pipes of 25mm diameter were used for both supplying air and discharging producer gas. Wood charcoals were mostly used for fuels. The concentration of CO ranged from 25 to 35%, comparable to the values presented in other studies. The temperature outside wall of the gasifier was measured up to $400^{\circ}C$, indicating a great heat loss. When glass wool was cover over the wall, some parts of wire mesh located in the bottom of the reactor were molten down. There were several modifications that should be made in order to improve its efficiency and obtain more stable continuous gasification, including insulation, reduction in pressure loss, durable bottom meshes, the optimum length of reaction part, and safety.

• Journal of The Korean Society of Agricultural Engineers
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• v.64 no.5
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• pp.9-16
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• 2022

Syngas, also known as synthesis gas, synthetic gas, or producer gas, is a combustible gas mixture generated when organic material (biomass) is heated in a gasifier with a limited airflow at a high temperature and elevated pressure. The present research was aimed at modifying the existing LPG engine generator for fully operated syngas. During this study, the designed gasifier-powered woodchip biomass was used for syngas production to generate power. A 6.0 kW LPG engine generator was modified and tested for operation on syngas. In the experiments, syngas and LPG fuels were tested as test fuels. For syngas production, 3 kg of dry woodchips were fed and burnt into the designed downdraft gasifier. The gasifier was connected to a blower coupled with a slider to help the air supply and control the ignition. The convection cooling system was connected to the syngas flow pipe for cooling the hot produce gas and filtering the impurities. For engine modification, a customized T-shaped flexible air/fuel mixture control device was designed for adjusting the correct stoichiometric air-fuel ratio ranging between 1:1.1 and 1.3 to match the combustion needs of the engine. The composition of produced syngas was analyzed using a gas analyzer and its composition was; 13~15 %, 10.2~13 %, 4.1~4.5 %, and 11.9~14.6 % for CO, H₂, CH₄, and CO₂ respectively with a heating value range of 4.12~5.01 MJ/Nm³. The maximum peak power output generated from syngas and LPG was recorded using a clamp-on power meter and found to be 3,689 watts and 5,001 watts, respectively. The results found from the experiment show that the LPG engine generator operated on syngas can be adopted with a de-ration rate of 73.78 % compared to its regular operating fuel.

• Microbiology and Biotechnology Letters
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• v.22 no.5
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• pp.550-556
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• 1994

For an extension of the palatable stage in Kimchi which was limited by further lowering pH as the fermentation proceeds, the starter culture of bacteriocin-producing Enterococcus faecium DU 0267 obtained from Kimchi was added at the preparation time, and pH, bacteriocin activity, growth of lactic acid bacterial group and gas production in Kimchi were examined during the fermentation at 10, 20 and 30$\circ$C . The pH of Kimchi fell rapidly to 4.0~4.2 in the early fermentation stage, and then, has gone down very slowly throughout further fermentation. The lactic acid bacte- ria, particularly lactobacilli and leuconostoc, were remarkably slower in its growth than those in the control. Although the patterns of these change during fermentation at different temperatures were similar, these effects by the addition of starter were enhanced at 10 and 20$\circ$C. The bacteriocin activity was increased rapidly during log phase of the bacteriocin producer strain in the early fermentation stage of Kimchi and reached their maximum after fermentation at 10$\circC, for 8 days and at 20 or 30$\circ$C for 2 days. Thereafter, the activity disappeared quickly. The gas production by fermentation was also suppressed considerably, and their volume produced after fermentation at 20$\circ$C for 14 days corresponded to 60% of those of the control.

• Journal of The Korean Society of Agricultural Engineers
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• v.59 no.1
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• pp.109-116
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• 2017

Biomass gasification produces syngas or producer gas as low calorific fuel gas that can be used as a fuel for combustion or prime movers as well as chemical synthesis. Internal combustion engines are readily available with lower costs and easily used for producing distributed power using biomass syngas. In this study, a dual fuel diesel engine was used to evaluate its performance when biomass syngas is used for fuel. The engine was originally developed for biogas application with a diesel engine with a 2,607 cc displacement. Both diesel fuel and syngas consumptions were observed at the different load conditions. The results indicate that the dual fuel engine showed a reasonably good performance and up to 63 % of diesel fuel saving.