The purpose of this study is to efficiently produce hydrogen gas from saccharide using 27.12 MHz radiofrequency (RF) in-liquid plasma with and without ultrasonic irradiation. The experiments were conducted adopting two different ultrasonic frequencies, one from a 29 kHz horn-type ultrasonic transducer and the other from a 1.6 MHz piezoelectric transducer. The glucose solution and cellulose suspension concentrations were varied from 0.5 wt% to 50 wt% and 0.5 wt% to 20 wt% respectively. Hydrogen gas was then produced by the decomposition of the glucose solution and cellulose suspension by RF in-liquid plasma with and without ultrasonic irradiation. The hydrogen production rate from glucose solution with ultrasonic irradiation applied was greater than that without ultrasonic irradiation. However, no hydrogen production rate enhancement was observed from decomposition of cellulose suspension with ultrasonic irradiation applied. Ultrasonic atomization and agitation enhanced the chemical reaction of nonvolatile glucose in in-liquid plasma. The increase of the gas production rate was caused by the direct decomposition of the glucose by the plasma due to the atomized glucose molecules being fed into the plasma in a bubble. In addition, by using a high-speed camera, it was clarified that acoustic streaming occurred when a 1.6 MHz piezoelectric transducer was used in the experiment.

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褐炭直接液化（BCL）プロセスの前処理として，褐炭の水熱処理と油添造粒の組み合わせ処理を検討した。水熱処理は，褐炭の脱灰と褐炭スラリーの高濃度化によって液化プラントの運転安定性と生産性の向上が期待される前処理であり，油添造粒法は，水熱処理で生成する褐炭・水スラリーに凝集溶剤を加え，褐炭と溶剤の凝集作用によって，水スラリーから処理炭を回収する方法である。本実験では豪州生褐炭を水熱処理し，BCL プロセスで製造した液化溶剤を用いて油添造粒を行った。320℃の水熱処理によって生褐炭の灰分量が約2/3 に減少し，続いて行なった油添造粒により水スラリーから水熱処理炭が容易に分離・回収され，その灰分は生褐炭の約1/2，水分は約1/5 に減少した。また，油添造粒で回収した水熱処理炭の造粒物に液化溶剤を加えることによって，液化プロセス原料スラリーを調製できることから，本法は褐炭直接液化プロセスの前処理として有効であることがわかった。

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石灰石焼成炉用燃料として塩素含有粒状廃プラスチックを用いた場合の炉内での塩素挙動について，熱力学的検討，電気炉による試験および実機への吹き込み試験を行った。粒状廃プラスチック中の塩素は，熱力学的には製品である生石灰には含有されず，HClとして排ガスに排出される。電気炉によるCaO の塩素化- 脱塩素試験においては，900℃に比較して，600℃の方が塩素化，脱塩素反応が速い。これは，表面に生成したCaCl₂ が900℃条件では溶融し，塩素化/ 脱塩素化反応を阻害したためと推定される。実機石灰石焼成炉での塩素含有粒状プラスチック吹込み試験において，粒状プラスチックの吹込み速度が速いほど，すなわち，炉内奥で粒状プラスチックを燃焼・塩化水素生成させることで，製品CaO への塩素転換率を低減できることを明らかとした。投入塩素は塩化水素として排出されず，微粒カルシウムに付着したダストとして系外に排出されるものと考えられる。

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Due to the high energy consumption and decreasing oil supply, the alternative energy sources such as biomass and agricultural waste can be considered as the main sources of energy in the future. Currently, one of the technologies to convert such biomass to more valuable products is biomass-to-liquid process. However, acid gases like CO₂ and H₂S are produced as intermediates causing the decrease in product heating values, operational problems, corrosion, and environmental concern. Therefore, the objective of this work is to simulate the absorption process of acid-gas cleaning by using various solutions at different operating conditions in order to meet the requirement. The results show that MDEA has higher performance to remove both gases compared to other chemicals. Furthermore, at 0.9 MPa and 25 °C, the treated gas provides 3.19 vol% CO₂ and 27.7 ppb of H₂S for MEA, 2.13 % CO₂ and 0.02 ppb of H₂S for MDEA and 7.45 % CO₂ and 1.12*10^-6 ppb of H₂S for Selexol. Moreover, the liquid flow rate, solution concentration and effects of temperature and pressure are also investigated for the optimal design of the absorption column.

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Technology of solar distillation technology is well established. However, application of locally available material in a manner techno-economically conducive to distillation has been always a point of investigation. In this paper, design, development and experimental results of four sloped pyramid shape top cover solar still is presented. The principal objective has been to use locally available foams to increase the distillate output. Experiments are carried out under the climatic conditions of Coimbatore, India (11° North, 77° East) under typical clear sky days. The system designed and developed is operated into two modes, (i) with thin water layer on the absorber and (ii) with black colored foam of varying dimensions are used in basin bed. The stainless steel basin of length 98.6 cm, breath 98.6 cm and 12.5 cm is used for water storage. An increase in condensate due to capillary rise is observed. System was further evaluated by recording variation in foam temperature, cover temperature, air temperature, ambient temperature and distillate output.

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