• Transactions of the Korean Society of Mechanical Engineers B
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• v.35 no.7
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• pp.693-699
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• 2011

Internal combustion engines running on syngas, which can be obtained from biomass or organic wastes, are expected to be one of the suitable alternatives for power generation, because they are environment-friendly and do not contribute to the depletion of fossil fuels. However, syngas has variable compositions and a lower heating value than pure natural gas, owing to which the combustion conditions need to be adjusted in order to achieve stable combustion. In this study, a gas that has the same characteristics as syngas, such as low heating value (LHV), was produced by mixing $N_2$ with compressed natural gas (CNG). In addition, this study investigates the combustion characteristics of syngas when it is mixed with hydrogen in a ratio ranging from 10% to 30% with a constant LHV of total gas.

• Journal of The Korean Society of Agricultural Engineers
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• v.59 no.5
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• pp.17-23
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• 2017

In South Korea, 25 % of annual agricultural residues (11.64 million tons) are unused. The hydrophilicity, low lower heating value (LHV), and low energy density of agricultural residues can be obstacles for efficient usage. Torrefaction, a low temperature pyrolysis process, can be a solution to overcome these disadvantage of agricultural residues. In this study, agricultural residues such as bean stem, pepper stem, perilla stem, sorghum stem, acorn shell, and ginkgo shell are torrefied at 200, 230, and $250^{\circ}C$ and evaluated energy properties, respectively. The torrefaction can increase the LHV and energy density rate of agricultural residues from 3,331~4,444 kcal/kg to 4,166~5,830 kcal/kg and 20~30 %, respectively.

• Journal of the Korean Applied Science and Technology
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• v.34 no.2
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• pp.327-337
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• 2017

A continuous low temperature ($510^{\circ}C{\sim}530^{\circ}C$) pyrolysis experiment in a pilot-scale of 85.3 kg/hr was carried out by the mixed feedstock of half dried digested sewage sludge and waste plastics. As a result, the amount of pyrolysis gas generated was maximum 68.3% of input dry mass and scored $40.9MJ/Nm^3$ of lower heating value (LHV), and the percentage of air inflow caused by continuous pyrolysis was 19.6%. The oil was produced 4.2% of the input dry mass, and the LHV was 32.5 MJ/kg. The sulfur and chlorine contents, which could cause corrosion of the facility, were found to be 0.2% or more respectively. The carbide generated was 27.5% of the input dry mass which shows LHV of 10.2 MJ/kg, and did not fall under designated waste from the elution test. The concentration of carbon monoxide, sulfur oxides and hydrogen cyanide of emitted flu gas from pyrolysis gas combustion was especially high, and dioxin (PCDDs/DFs) was within the legal standards as $0.034ng-TEQ/Sm^3$. Among the 47 water pollutant contents of waste water generated from dry flue gas condensation, several contents such as total nitrogen, n-H extract and cyanide showed high concentration. Therefore, the merge treatment in the sewage treatment plants after pre-treatment could be considered.

• Journal of ILASS-Korea
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• v.16 no.3
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• pp.119-125
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• 2011

Due to the oxygen contents in biodiesel, application of the fuel to compression ignition engines has significant advantages in terms of lowering PM formation in the combustion chamber. In recent days, considerable studies have been performed to extend the low temperature combustion regime in diesel engines by applying biodiesel fuel. In this work, low temperature combustion characteristics of biodiesel blends in dilution controlled regime were investigated at a fixed engine operating condition in a single cylinder diesel engine, and the comparisons of engine performances and emission characteristics between biodiesel and conventional diesel fuel were carried out. Results show that low temperature combustion can be achieved at $O_2$ concentration of around 7~8% for both biodiesel and diesel fuels. Especially, by use of biodiesel, noticeable reduction (maximum 50% of smoke was observed at low and middle loads compared to conventional diesel fuel. In addition, THC(total hydrocarbon) and CO(Carbon monoxide) emissions decreased by substantial amounts for biodiesel fuel. Results also indicate that even though about 10% loss of engine power as well as 14% increase of fuel consumption rate was observed due to lower LHV(lower heating value) of biodiesel, thermal efficiencies for biodiesel fuel were slightly elevated because of power recovery phenomenon.

• Resources Recycling
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• v.21 no.1
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• pp.17-29
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• 2012

potential assessment of converting closed non sanitary landfills into sustainable landfill through the reclamation works(= landfill mining project) of illegal landfill discovered in land development site using Sustainable Landfill Reclamation system(SLR-system) was investigated. The SLR system had treatment capacity of 91.4 $m^3/hr$ (130.61 ton/hr) in condition of 28.0% of water content. Recovery ratio and purity of sorted soil were 98.9% and 99.66%, respectively. Sorted combustibles were 91.8% and 92.0%, respectively. Especially, high heating value (HHV) and low heating value(LHV) of combustibles were 4,282kcal/kg and 3,636 kcal/kg, respectively, in considering the energy content and recovery ratio of combustibles. Therefore, combustibles separated from landfill site have higher value than Fluff RDF standard value(3,500kcal/kg) of MOE. RDF can be produced with combustibles by 84.43%. Averaged size and organic foreign matter content of the sorted soil were less than 035mm and 0.31 %(VN), respectively. In addition, concentration of all contents of hazardous matters containing soils met safety standards. Therefore, it is possible to be recycled as refilling and cover materials to rebuild Sustainable landfills by 98.42%.

• Journal of Korean Society of Environmental Engineers
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• v.34 no.9
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• pp.583-589
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• 2012

The various promotion countermeasures such as solidification, carbonization, and the creation of cement materials have been considered to existing treatment methods such as incineration and the creation of composts, since direct landfill was prohibited for encouraging the recycling based on the sludge treatment on land. The Main objective of this study is to investigate the feasibility of co-incineration for MSW (Municipal Solid Waste) and SS (Sewage Sludge) through the change of heat and atmospheric pollutants. In this study, LHV (Low Heating Value) is 100~300 kcal/kg because the MC (Moisture Content) of de-hydrated sewage sludge is approximately 80%. From the results, we knew the feasibility of co-incineration for MSW (80%) and SS (20%). As the co-incineration rate of SS up to 20% became higher, the loading of heat and atmospheric pollutants was not influenced.

• Journal of Energy Engineering
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• v.23 no.4
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• pp.9-18
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• 2014

These test methods, the current domestic vehicles fuel economy calculation method is tested on a dynamometer for vehicles after you have installed the vehicle, given the test mode(FTP-75 & HWFET mode, etc.) are measured by vehicle emissions and fuel economy by seeking to have the results approach, the carbon balance method. At this point, using the carbon balance method is a test method was developed seeking fuel for a standard fuel properties, where the value of the constant and saved test was measured in THC, CO, $CO_2$ has a value calculation. Therefore, use fuel which is changed every time you test the fuel properties characteristics are not considered exactly. In this study, using the carbon balance method and fluid flow rate of the fuel used in the actual test is measured by comparing the results with the flow measurement methods, properties of the fuel used for the test attribute to study ways that can be considered, taking into account the physical attributes of a more diverse fuel line and fuel economy improved measurement methods that can be reviewed.