The performance investigations of subcritical ORC supercritical ORC and trilateral Rankine cycle (TLC) power plants with the heat source temperatures of 210-250°C were conducted and compared in this study. Several working fluids were evaluated. A MATLAB code was developed and used in this study. The thermodynamic properties of the working fluids were calculated by using NIST REFPROP program. The justification of the code was validated with a result taken from the literature. The optimal operating conditions were searched using the golden-section technique. The maximum net output power of 141.72 kW was obtained when using the supercritical ORC plant with R141b as its working fluid and the heat source temperature was at 250°C. The corresponding cycle efficiency was 16.25%. When using the subcritical plant at the same heat source temperature the maximum net output power of 133.40 kW and cycle efficiency of 15.70% are obtained when pentane is used as the working fluid. Furthermore the net output power of 133.82 kW and cycle efficiency of 14.90% are obtained when using R141b as the working fluid in the TLC power plant. According to the off-design simulations an appropriate adjustment of the working fluid flow rate can mitigate the variation of the net output power.

The ORC power plant is a promising technology to generate electricity from low-temperature heat sources. However implementation of the ORC for low capacity electricity generation is unattractive at the commercial level. Scroll compressors are massively produced to be used in refrigeration and air-conditioning applications. Using a scroll compressor in reverse as an expander can reduce the investment cost of low-capacity ORC power plants. In this study 2 scroll compressors that are available in the automotive air-conditioning market of Thailand were modified and used as the expander of a 1 kW ORC power plant. The performances of these 2 scrolls were compared and the plant performance was investigated. A heat source temperature from 100°C to 150°C was supplied to the plant. It was found that the gross power is higher by 18-35% for the larger expander (110 cc/rev) than for the smaller expander (85.7 cc/rev). The larger one provides the isentropic efficiency of 37-76% and the gross power of 806-1926 W. In addition the effects of check valve installation were examined and compared with those of the tests without check valve installation. It was revealed that the isentropic efficiency increases by 18% while the gross power decreases by 4-22% when the check valve was installed.

The solar chimney power plant (SCPP) has been proposed as a promising alternative power plant. According to the literature the chimney for commercial-scale SCPPs should be about 1 km high. The construction of these tall chimneys is very challenging and the construction cost is enormous. The sloped solar chimney power plant (SSCPP) is a variation of the SCPP. One of the SSCPP’s prominent feature is that its collector is sloped and then its chimney can be shorter than that of the SCPP. This leads to a lower investment cost of SSCPPs compared with that of SCPPs. Also previous studies show that the industrial waste heat potential of Thailand is considerable and should be investigated. As a result this study developed a mathematical model for designing a sloped solar chimney power plant powered by industrial waste heat (SSCPP-WH). The model was justified by validation using experimental data. Then several SSCPPs with different geometrical dimensions were simulated to determine a proper dimension that has the lowest levelized cost of electricity (LCOE). It was found that the LCOE is about 0.14 USD/kWh the payback period is about 11 years system efficiency of 1.3% and collector efficiency of 36%. for an SSCPP-WH with a collector area of 49000 m2 chimney height of 45m flow area ratio between solar collector inlet and solar collector outlet (AR12) of 14 and waste heat of 10 MW. It was also found that the payback period of SSCPP with no supplied waste heat is lower than that of some SSCPP-WHs. To make sure that the payback period for the SSCPP-WH is faster than that of SSCPP with no waste heat a ratio of the supplied waste heat to the absorbed solar energy of the SSCPP-WH must be greater than 0.34.

The research project on The potential of Siphonodon celastrineus Griff traditional medicinal plants of Thailand for treatment from local wisdom knowledge lead to the development of sustainable use with the objective of studying the botanical phytochemical and biological activity of the Siphonodon celastrineus to create confidence in the use of S. celastrineus in herbal medicine by using the bark leaves and fruit of the S. celastrineus to extract with 3 types of solvents. Each of hexane ethyl acetate and methanol respectively from low to high polarity. All nine extracts will be extracted. Preliminary examinations for phytochemistry Antioxidant activity by DPPH radical scavenging assay and quantitative determination of phenolic compounds by Folin-Ciocalteu method and antimicrobial activity were tested. The research found that. 1. The extract of the results of the methanol layer of the S.celastrineus shows a reduction in the amount of 11-diphenol-2-picrylhydrazyl (DPPH) had the highest EC50 equal to 31 mg/ml. The amount of phenol compounds found that the extracts from the methanol extract of S. celastrineus contain the amount of phenol. The highest concentration of 95.23 mg GAE / g dw 2. Extract from the bark of the S. celastrineus with methanol showed the best inhibition of the growth of Vibrio paraheamolyticus with the MIC value of 15.60 mg/ml. The extracts of the S. celastrineus leaf extracts with hexane showed the best inhibition of the growth of Vibrio cholerae with the MIC value equal to 31.25 mg/ml and leaf extracts with ethyl acetate showed the best inhibitory effect on the growth of Vibrio cholerae with a MIC value of 31.25 mg/ml and the extract of the fruit with ethyl acetate to inhibit the growth of Vibrio paraheamolyticus most with MIC equal to 15.60 mg/ml.

The experiment was in a type of 4 experimental wells with the size of width x length x height was equal to 0.5x1x 0.5 meters including the experimental well which had plants of Colocasiaesculenta (L.)Schott PandanusamaryllifoliusRoxb and Canna indica Linn and the rest was the control well without any plants. The time period of Alternating 5 days flooding and 2 days drying Soil. The parameter studied included BOD value suspended solids Total KjeldahlNitrogen Total Phosphorus pH and Oil and Grease. The research result found that the experimental well which had Colocasiaesculenta (L.)Schott PandanusamaryllifoliusRoxb and Canna indica Linn had the effectiveness in wastewater treatment higher than the control well without any plants. After treatment with the control well without any plants the experimental which had plants of Colocasiaesculenta (L.)Schott PandanusamaryllifoliusRoxb and Canna indicaLinn with the romoval percentage of BOD value at 22.66 69.93 63.48 and 76.37 respectively.Suspended Solids at 22.66 69.93 63.48 and 76.37 respectively.TotalKjeldahl Nitrogen at 26.41 68.67 64.21 and 72.99 respectively.Total Phosphorus at 52.26 81.6975.73and79.88respectively.pHat6.42 6.556.64and 6.88 respectively.Oil and Grease at 62.08 78.75 76.47 and 80.39respectively.