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The suitable size (electricity output capacity) of micro gas turbine cogeneration systems (MGT-CGSs) depending on scale of the sewage treatment plant was investigated. Since heat demand of the plant is affected by ambient temperature, performance under three typical ambient temperature conditions was investigated. Considering operation of the MGT-CGS under various loads and efficiency of the MGT-CGS under a partial load condition, the optimal combination of MGT-CGSs (MGT-Combination) with different sizes, 30 kW, 65 kW and 200 kW, was also proposed. An actual middle-scale plant was adopted as the analysis model, and it was scaled down to 0.50 and 0.25 in cases of smaller scale. Excluding MGT-Combination, it was found that the MGT that has approximately the same fuel energy input under full load as the biogas energy produced in the plant has the highest efficiency. However, in the case of heat demand of the plant varying throughout the year such as the operation in a cold region, partial load operation will be frequent and efficiency will decrease. Furthermore, MGT-Combination has the highest efficiency but its efficiency will be the same as that of the other MGT-CGSs when only comparatively constant operation is required throughout the year such as operation in a tropical region.

In this study, efficient configuration of a biogas-fuelled cogeneration system (CGS) in a sewage treatment facility was investigated. The efficient configuration of the CGS was clarified on the basis of the relationship between exhaust heat recovery efficiency (ηehr) of the CGS and the ratio of yearly average heat demand to yearly average biogas production of the facility (Qh.d/Qb.p). The CGS was assumed to be used under Qh.d/Qb.p ηehr conditions. It was found that although the CGS was able to cover total heat demand of the facility by only consuming biogas produced, from the point of view of energy utilization, reduction of unutilized biogas and reduction of electricity demand efficiencies, the most efficient CGS was obtained under the Qh.d/Qb.p≈ηehr condition. Under the Qh.d/Qb.p≈ηehr condition, energy utilization, reduction of unutilized biogas, and reduction of electrical demand efficiencies were 0.64, 0.99, and 0.32, respectively, whereas under the Qh.d/Qb.p ηehr conditions, energy utilization, reduction of unutilized biogas, and reduction of electrical demand efficiencies were in ranges of 0.56–0.64, 0.43–0.99, and 0.16–0.20, respectively. A more efficient system can be obtained if a CGS with lower ηehr such as a fuel cell is used under the Qh.d/Qb.p ηehr condition. © 2011 Wiley Periodicals, Inc. Heat Trans Asian Res; Published online in Wiley Online Library (wileyonlinelibrary.com/journal/htj). DOI 10.1002/htj.20389

A small-scale prime mover especially micro gas turbine is a key factor in order to widespread the utilization of biogas. It is well known that a performance of large-scale gas turbine is greatly affected by its inlet air temperature. However, the effect of the inlet air temperature on the performance of small-scale gas turbine (micro gas turbine) is not widely reported. The purpose of the present study is to investigate the effect of the inlet air temperature on the performance of a micro gas turbine (MGT) with cogeneration system (CGS) arrangement. An analysis model of the MGT-CGS was set up on the basis of experimental results obtained in a previous study and a manufacturer standard data, and it was analysed under a various ambient temperature condition in a cold region. The results show that when ambient temperature increased, electrical efficiency η_ of the MGT decreased but exhaust heat recovery η_ increased. It was also found that when ambient temperature increased, exhaust heat to mass flow rate Q_/m_e and exhaust heat recovery to mass flow rate Q_/m_e increased, with maximum ratios of 259 kJ/kg and 200 kJ/kg, respectively were found in summer peak. Furthermore, it was also found that the exhaust heat to power ratio Q_/P_e had a similar characteristic with exhaust heat recovery to power ratio Q_/P_e. Q_/P_e and Q_/P_e increased with the increase of ambient temperature. Moreover, although different values of total energy efficiency, fuel energy saving and CO_2 reduction for every temperature condition were found comparing with a two conventional system that were considered, the MGT-CGS could annually reduce 30,000-80,000 m^3/y of fuel consumption and 35?94 t-CO_2/y of CO_2 emissions.

The use of biogas by a cogeneration system (CGS) is a promising technology as an efficient method of energy utilization. Sewage treatment plants (STPs) are facilities that have been continuously producing biogas, and therefore the potential of application of a biogas-fuelled CGS in an STP is estimated to be very high. However, there have been few reports on efficient utilization of biogas by a CGS, especially in cold regions. Since ambient temperature in a cold region is low and varies greatly, heat demand in the STP is also great and varies greatly throughout the year. Thus, auxiliary components such as a boiler, heat pump and gas storage system are also required to cover the total heat demand throughout a year. In the present study, adopting an actual STP in a cold region and a micro gas turbine as the CGS prime mover, performance of a biogas-fuelled CGS was investigated. The performances of four possible arrangements of the CGS with different auxiliary components were compared to the performance of a conventional system. It was found that all CGS arrangements could cover the total heat demand by only using biogas produced in the facility. The CGS arrangements could reduce electrical power demand by 23?31%, recover 74?78% of the energy of biogas produced, and utilize almost 100% of the biogas. The CGS arrangements with a heat pump were more efficient than the CGS arrangements with a boiler. CGS arrangements that include a gas storage system will enable efficient utilization of biogas and recovered exhaust heat.

In recent years, production of biogas by an anaerobic digestion method has been reconsidered as an alternative means for producing clean fuel. Thus, research on various aspects of biogas production by anaerobic digestion has become important for its widespread utilization. One of the important aspects is energy balance of the process. The energy balance is affected by a heat demand, whereas the heat demand is affected by ambient temperature. In the present study, in order to clarify the effect of ambient temperature on the energy balance of anaerobic digestion, typical municipal sewage sludge anaerobic digestion in an actual wastewater treatment plant was adopted as analysis model and was studied under various temperature conditions. It was found that the heat demand for heating the sludge was temperature-dependent and that 26?39% of the total amount of heat demand was heat losses from digester tanks. From the energy balance, it was found that net energy can be produced by the anaerobic digestion in any region and season in Japan, and this shown that it has a possiblity to be a new energy resource. It was also shown that, when ambient temperature became closer to the digestion temperature, more efficient anaerobic digestion can be obtained. These results were confirmed by indexes of energy balance that were defined in this study, with notable proportional relations being found between indexes and ambient temperature. Ratio of energy of heat demand to biogas produced had an inverse proportional relation with ambient temperature, whereas ratio of energy of net energy to biogas produced had a proportional relation, and ranges of these values in all of Japan were 0.13?0.44 and 0.45?0.84, respectively.

According to the third conference of parties (COP3), Japan has set a target of reducing greenhouse gas emissions by 6% by the year 2010. Cogeneration system is a recently potent method which its environmental benefits, through the highly efficient utilization of fuel that is related to reduction emissions. The particular purpose of this paper is to support the selection of cogeneration technologies by acquiring the optimal useful thermal energy and electrical power from system with well-efficiency balance method and fuel saving approaching method. When a micro gas turbine (MGT) is operated under ambient condition, the discharged hot gases from the MGT may be expanded at its exhaust stage and cooled by an exhaust heat exchanger which composes with a single stage absorption heat exchanger. The performance and annual total fuel saving amount of cogeneration plant will be investigated and compared with separated production of heat and power system. Eventually, this cogeneration plant will be reduced the fuel consumption rate in operation that will be also reduced the emissions and fuel cost when the system will gain highly efficiency of thermal energy and electrical power., application/pdf

According to the third conference of parties (COP3), Japan has set a target of reducing greenhouse gas emissions by 6% by the year 2010. Many believe that the bulk utilization of fossil fuel influences to the damaging environmental effect. The objective of this paper is to propose an effective method for this goad which is possible to clarify a noticeable utilization of renewable fuel in a micro gas turbine cogeneration system in cold region. Moreover, analysis of renewable fuel, biogas production indicates that production amount becomes largest in hot season, while the total heat energy demand is lowest on during three years. Biogas storage is also adapted for the delay between peak energy supply and demand. Biogas hydrate formation is examined by resource from laboratory experiments and simulation of integration into an existing cogeneration arrangement. The proposed system can be successfully supported the use and reuse of renewable fuel for providing to substantial emission and clean development mechanism for reducing greenhouse gas emission., application/pdf

To fabricate thermal spraying coatings with good reproducibility, it is necessary to improve the process of the equalization of both thermal history and impacting behavior of the particles. In this study, the characteristics of the solution type plasma spraying using the hollow-cathode type torch are investigated. The physical and mechanical properties that are different from usual thermal spraying coatings are described. By using solutions including metal ingredients in a state of ion, colloid or sol, thinner coating that cannot be made by conventional plasma spraying methods is formed on various substrates. The coatings are uniform in appearance.

This study aimed to manufacture the environmental correspondence materials with functions of water repellency and antimicrobial activity according to make a surface by the thermal spraying method. For the water repellency characteristic was found on the fluorine-carbon, and the antimicrobial activity was detected by using the CuCl2¤3Cu(OH)2 powders, the thermal spraying coatings were made by the compound wire where two kinds of the powders were added to the aluminum tube. The functions of water repellency and antimicrobial activity were investigated. The results of the experiment show that two kinds of the CuCl2¤3Cu(OH)2 powders were well dispersed and settled. The mean contact angle was 139° tested by the water droplet method, which shows no much different from the contact angle of the coatings made by only the fluorine-carbon filled wire. Furthermore, by adding the CuCl2¤3Cu(OH)2 powders, at the same time as the water repellency characteristic, the remarkable antimicrobial activity was also clarified form the results of the culture experiment basing on the JIS standardization.

The effect of thyroid hormone on immune function is unclear. The influence of L-triiodothyronine on expression of the interleukin-2 receptor alpha chain by peripheral blood mononuclear cells from healthy volunteers and YT cells (an interleukin-2 independent natural killer-like cell line) was examined. Concanavalin A stimulation significantly (p

Nineteen patients aged > 60 years with chronic hepatitis C (CHC) received interferon (IFN) therapy and a complete response (CR) was achieved by five of them (26%). The incidence of CH with severe fibrosis in this elderly group was significantly higher than in another 52 patients with CHC who were < 60 years of age (the younger group; P < 0.05). There was no significant difference in the hepatitis C virus (HCV) genotype distribution between the elderly group and the younger group. However, the HCV-RNA titre was significantly higher in the elderly group than in the younger group (P < 0.05). There was no significant difference in the efficacy rate of IFN in the elderly and younger groups after standardization of the background factors. In the elderly group, the HCV-RNA titre was significantly lower in the patients achieving CR than in those with no response (P < 0.05). These data suggest that elderly patients with a low HCV-RNA titre can still respond well to IFN therapy.

Efficient utilization of biomass by a cogeneration system (CGS) is a promising technology for promoting sustainable energy development. Sewage treatment plants are facilities that have been continuously producing biogas by anaerobic digestion. Thus, the potential of a biogas-fuelled CGS in a sewage treatment plant is estimated to be very high. However, there have been few reports on the performance of a biogas-fuelled CGS, particularly regarding the effect of ambient temperature on its performance, and the most efficient arrangement of a biogas-fuelled CGS remains unknown. In this study, performance of a biogas-fuelled CGS was simulated under three typical ambient temperature (low, medium and high) conditions using actual data for a CGS with a micro gas turbine. In the beginning of this study, the relation of energy balance of the plant and ambient temperature was clarified. It was found that the amount of heat demand is ambient temperature-dependent but that the amount of biogas fuel produced is almost constant throughout the year. When a boiler is replaced with a biogas-fuelled CGS to utilize the biogas, under a high temperature condition, the CGS is not able to fully utilize all of the biogas produced, and therefore another pathway of biogas utilization is needed. Under a medium temperature condition, a gas storage system is needed for using biogas efficiently. However, some of the biogas still cannot be utilized efficiently. Under a low temperature condition, since ambient temperature varies greatly between summer and winter, the amount of heat demand of the plant also varies greatly throughout the year. This leads to an imbalance in biogas production and heat demand, and therefore attention must be given to energy management in this condition. The combination of other auxiliary equipment such as a boiler, heat pump and gas storage with the CGS is required in order to cover the total heat demand throughout the year. Four possible arrangements of the CGS with different auxiliary components were proposed and their performances were compared. It was found that all of the proposed CGS arrangements can sufficiently cover the total heat demand by only using biogas produced in the facility. Compared to the conventional system, all proposed CGS arrangements can reduce electrical power demand by 23∼28%, recover 74∼77% of the energy of biogas produced, and utilize almost 100% of the biogas produced. The arrangement with a heat pump is more efficient than the arrangement with a boiler. It was also found that excess biogas in summer can be used in winter by storing the biogas. Thus, a CGS arrangement that includes a gas storage system will enable efficient utilization of biogas and recovered exhaust heat.Copyright © 2011 by ASME

We measured soluble interleukin 2 receptor, a part of the Tac protein (p55), in peripheral blood to study the immunological condition of the T cell in autoimmune thyroid disease. In 26 patients with untreated Graves' disease and 7 hyperthyroid patients with Hashimoto's thyroiditis, the mean levels of soluble IL-2 receptor were both significantly higher than in normal controls (1497±649 (mean ± sd), 641±137 vs 221±63 103 U/l, p3 was administered to subjects in remission from Graves' disease and in normal controls, the soluble IL-2 receptor levels significantly increased. Moreover, the mean level of soluble IL-2 receptor in patients with toxic multinodular goitre was also significantly higher than in normal controls (411±148 vs 221±63 103U/l, p

We performed laparoscopy on 72 patients with chronic hepatitis C (CH-C) to elucidate its morphological features and characteristics relating to its progressive clinical course. We then compared these findings with those of 188 patients with chronic hepatitis B (CH-B). The frequency of reddish hepatic markings was almost the same in the patients with CH-B (21%) and the patients with CH-C (24%). In the patients with CH-B, reddish markings were present more frequently in the subjects with sublobular hepatic necrosis (34%) than in those without it (5%, p

A 77-year-old man was admitted to the hospital with a thyroid nodule. The levels of serum tumor-associated carbohydrate antigens (CA 50, CA 19-9) and thyroglobulin (HTG) were markedly increased. We performed total thyroidectomy and right neck lymph node dissection. After treatment, the serum CA 50, CA 19-9 and HTG levels were markedly decreased. Histological examination of the thyroid tumor showed papillary adenocarcinoma and the dissected neck lymph nodes contained metastatic adenocarcinoma. The expression of CA 50 and CA 19-9 (defined by the monoclonal antibodies) was studied by immunoperoxidase staining from the normal and carcinomatous thyroid tissues and the dissected neck lymph node. CA 50 was expressed more strongly by the carcinoma cells than CA 19-9. The positive rates for serum CA 50 and CA 19-9 levels in other patients with papillary adenocarcinoma were not significantly higher compared with patients with benign nodules and normal subjects. But a significant positive correlation was found between the diameter of the carcinoma and the serum levels of CA 50 and CA 19-9. These results suggest that the serum levels of CA 50 and CA 19-9 might not become useful markers for diagnosing carcinoma of the thyroid, but might be useful markers for monitoring the growth or recurrence of papillary adenocarcinoma of the thyroid in patients with high serum levels of CA 50 and CA 19-9.

According to the third conference of parties (COP3), Japan has set a target of reducing greenhouse gas emissions by 6% by the year 2010. One of the effective methods proposed to meet this goad is micro gas turbine cogeneration, which is increasing in popularity in industry. In the present study, the performance of a cogeneration system in cold regions and the applicability of such a system to a sewage treatment plant is investigated. The anaerobic fermentation digester produces biogas as a suitable fuel input for a cogeneration system, and the use of this waste gas provides substantial emission and environmental improvements. Analysis of biogas production indicates that production is high in the hot season, while the heat energy demand is highest in the cold season. As a method for biogas storage to adapt to the delay between peak energy supply and peak energy demand, biogas hydrate formation is examined by laboratory experiments and simulations of integration into an existing cogeneration system. It is found that hydrate storage is a cost-effective storage solution for biogas generated by sewage treatment facilities. Also, it can be suggested necessary energy for the hydrate production.

A 57-year-old woman was admitted with symmetrical proximal muscle weakness, liver dysfunction, abnormal muscle enzymes, and she was an antibody to hepatitis B e (anti-HBe) positive hepatitis B virus (HBV) carrier. Biopsy of her left quadriceps femoris showed myositis, so prednisolone was started at 40 mg/day. However, her hepatic function deteriorated and liver biopsy after 4 months showed acute hepatitis with partial submassive necrosis. Treatment with interferon-alpha and cyclosporin A progressively reduced the transaminase and HBV-DNA levels. Early treatment with interferon-alpha plus cyclosporin A can control exacerbation of hepatitis B.