• Journal of Environmental Health Sciences
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• v.20 no.3
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• pp.13-18
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• 1994

Information on the heating values of municipal solid wastes is very important in evaluating the feasibility of incineration and RDF (Refuse Derived Fuel) manufacture. This paper describes the forecasting methods about the lower heating values of municipal solid wastes. The lower heating values are forecast by the heating values of physical components. The municipal solid wastes consist of paper, food wastes, textiles, plastics, wood and rubber (contained leather). These are the physical components of municipal solid wastes.

• Journal of Biosystems Engineering
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• v.26 no.2
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• pp.155-162
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• 2001

The greenhouse heating system with heat pump was built for development of simulation model and validation. The computer simulation model for the system to predict temperature of air and soil and moisture content of soil in the greenhouse were developed, and its validity was justified by actual data. From the analysis of experimentally measured data and the simulation output, following results were obtained. 1. The expected values of inside air temperature for the heating system with heat pump were very much close to the experimental values. 2. In the heating system with heat pump, the expected values of day time surface temperature of soil by computer simulation were very much similar to the measured values, but those of night time were higher than the measured value by at most 2.0$\^{C}$. 3. The simulation model predicted temperature of greenhouse film as of 1$\^{C}$ below than the mean value of ambient air and greenhouse air temperature. 4. Heat loss value of daytime was found to be larger than that of nigh as much as 1.3 to 2.3 times for the heating system with heat pump. 5. In the heating system with heat pump, when the lowest ambient temperature was -8$\^{C}$∼-7$\^{C}$ the air temperature of greenhouse was 5$\^{C}$∼6$\^{C}$, thus the heat pump heating system contributed in greenhouse heating by 13$\^{C}$.

• Journal of Biosystems Engineering
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• v.38 no.3
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• pp.180-184
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• 2013

Purpose: This study explored the factors influencing heating value in the process of torrefaction of water hyacinth. Methods: Torrefaction was applied with three temperature settings (200, 300, $400^{\circ}C$) and three time settings (1, 2, 3 h) using small electric heaters (11.3L of holding volume). This study investigated the heating values with the washing process and process factors influenced the torrefaction. In addition, this study compared the heating values in washed and unwashed samples and suggested the optimal conditions for increasing heating value. Results: Torrefaction increased the heating value by 8.18 ~ 30.04%. Comparing heating values of each condition, the optimal temperature for torrefaction was $300^{\circ}C$ and holding time was 1 hour. The washing process increased the heating value by 19 ~ 27%. The heating value of the sample treated at $300^{\circ}C$ for three hours was 4310.80 kcal/kg, which was greater than the first class wood pellet of 4300 kcal/kg. Conclusions: This study proved that the torrefaction and washing process increased the heating value of water hyacinth. Therefore, water hyacinth is expected to be an eco-friendly biomass which substitutes for wood pellet.

• Proceedings of the Korean Society of Agricultural Engineers Conference
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• 2000.10a
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• pp.563-568
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• 2000

Animal waste is a major agricultural waste or wastewater that requires appropriate treatment to prevent environmental pollution. In this presentation, it is examined if incineration of manure compost is an alternative to treatment of animal waste. Heating values of selected biomass including manure compost were obtained using a bomb calorimeter. Based on heating values of manure and manure compost, ranging from 1200 - 1500 kcal/kg on wet base, incineration could be an alternative for animal waste treatment if available land is limited for land application and sufficient reduction of water content in manure compost.

• 한국연소학회:학술대회논문집
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• 2015.12a
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• pp.57-59
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• 2015

A method to measure heating value of natural gas using sound velocity and thermal conductivity is proposed to solve the low heating value issues of imported natural gas in South Korea. Natural gas generally consists of methane, butane, ethane, and inert gases. Heating value changes as the gas material properties, such as density, wobbe index, etc., varies. It is highly important to measure heating values of natural gases accurately because measuring the heating value depends on the given natural gases' components. Therefore, sound velocity and thermal conductivity is measured to estimate indirectly heating value of Natural gas with their changed components.

• Journal of Practical Agriculture & Fisheries Research
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• v.6 no.1
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• pp.143-154
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• 2004

The value of daily heating degree hour(described as DH hereafter) is essential for calculating the heating load of a greenhouse during the winter months. Many researchers have so for proposed different models for estimating DH value. Models for estimating DH have been investigated DH(unit, ℃·h·year^-1) in this paper. The comparisons of standard and existed DH values were made to know the estimation error of each model proposed so far. The standard DH values and other proposed DH values have were obtained for the inside setpoint temperatures of 9, 13, 16 and 20℃ in greenhouse, estimated based on meterological data from 1961 to 2000 according to locals, and standard DH values were independent and existed DH values were dependent. Among the various model, the one developed theoretically by Mihara modified to author was the best fitting for standard DH values. The DH values were obtained for the inside setpoint temperature of 9, 13, 16 and 20℃ by Modified Mihara's model. A new DH contour line graph was proposed using Modified Mihara's model. Using the DH contour line graph, the DH values can be obtained easily for any setpoint according to local.

• Textile Coloration and Finishing
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• v.28 no.4
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• pp.299-307
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• 2016

In order to clarify the availability of heat treatment for catechu dyeing, effect of color developing by heating process on cotton fabrics dyed with catechu extract was investigated. Dyed fabrics were heated various time(min) at $150^{\circ}C$. The cases of non-mordanting and mordanting were compared, and examined the effect of sodium acetate as an agent to promote the color developing to fabrics. Experiments with after-mordanting method showed that various colors can be obtained using catechu. K/S values of dyed fabrics with Al, Cu, Fe mordant were higher than the case of no mordant. The fabric by Cu mordanting showed 3 times to the case of no mordant. Fabrics dyed with catechu by mordanting lowered $L^*$ value while there was little change in $a^*$, $b^*$ value as the heating process progressed. Therefore, K/S values were increased due to heating process. The effects of adding sodium acetate in dyeing bath on dyed fabrics were shown higher K/S values, and the $L^*$ values were lower than those without sodium acetate according to heating time increase. The result show sodium acetate had a promoting effect on the color developing to the fabrics by heating process, it was very effective.

• Transactions of the Korean Society of Automotive Engineers
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• v.10 no.6
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• pp.72-79
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• 2002

The main objective of this study is to investigate the relationship between chemical structure and higher heating value of reformed diesel fuels by ultrasonic irradiation. In order to analyze the chemical structure changes of the reformed diesel fuels by ultrasonic irradiation, Proton nuclear magnetic resonance spectrometer(1H-NMR) was used and to analyze the effect of higher heating values of these diesel fuels, the bomb calorimeter was used. From the study, following conclusive remarks can be made. 1) The aromatic carbon percentages and higher heating values of the reformed diesel fuels by ultrasonic irradiation increased more than the conventional diesel ones. 2) The aromatics percentages and Branch Index(BI) of the reformed diesel fuels by ultrasonic irradiation decreased more than the conventional diesel ones. 3) The higher heating values on both for conventional fuel and reformed diesel fuels by ultrasonic energy irradiation is directly proportional to aromatic carbon percentages and inversely proportional to aromatic percentages and BI for these fuels.

• Journal of ILASS-Korea
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• v.6 no.4
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• pp.22-30
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• 2001

The objective of this study is to develop the new equations for the calculation of higher heating values(HHVs) of reformed diesel fuels by ultrasonic treatment. Therefore, higher heating values of reformed diesel fuels by ultrasonic treatment are determined experimentally and calculated from their viscosity and surface tension measurements. The HHVs of the fuels are supposed to be a function of viscosity(Pa s) and surface tension(N/cm). The equations developed for the samples represent the correlation obtained by means of regression analysis. The HHVs calculated by developing new equations using viscosities showes the differences from the measured values ranging from -0.66 to 1.19 % and the correlation coefficient was -0.9411. The HHVs calculated by developing new equations using surface tensions showed the differences from the measured values ranging from -0.70 to 1.51 % and the correlation coefficient was 0.9999. The viscosity and the surface tension are characteristic properties of ultrasonic reformed diesel fuels for developing new formulae.

• Korean Journal of Food Science and Technology
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• v.22 no.5
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• pp.575-581
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• 1990

The existence of the equivalent point for a thermal processing system was demonstrated using arbitrarily chosen ideal direct heating curves. i.e. isothermal heating curves at $120^{\circ}C$ for 10min and at $135^{\circ}C$ for 10sec. Under these conditions, G-values and F-values were calculated at various values of Ea- and z-values by applying the Arrhenius and the Bigelow models respectively. The equivalent time and equivalent temperature were determined by both line intersection and linear regression methods. The equivalent points estimated by both the line intersection and the linear regression methods were consistent and their values were the same as the heating time and temperature of the ideal direct heating curves.