To explore the factors that affect coke strength in the meso-scale pore structure of coke, we investigated the relationship between the strength and meso-scale pore structure of the polished surface of coke sample. Coke was fractured using diametral-compression tests, and the tensile strength of coke was measured. Furthermore, we observed the polished surface of coke and obtained combined images with a size of 10 mm × 10 mm. The size and roundness of the pores were evaluated by image analysis. The pores were classified according to the pore size, and the strength of coke with many pores with a diameter of more than 1000 µm was indicated to be low. Moreover, the roundness of pores with a diameter of more than 1000 µm was low. Therefore, pores with diameter of more than 1000 µm and low roundness are considered to greatly affect the strength of coke in a meso-scale structure.

Filtration experiments were conducted using artificial wastewater at 20 °C and 60 °C to explain the relationship between the separation ability of oil-water separation equipment and the recovery rate of suspended solids (SS) recovery equipment for oil concentrations. Based on the characteristics of oil and SS explained by the filtration experiments, an economic evaluation method for a wastewater treatment system was proposed for two cases: using oil-water separation equipment without SS recovery equipment (single use) and using oil-water separation equipment with SS recovery equipment (combination use) using Separative Work Unit (SWU). The separation ability of oil-water separation equipment could determine the required recovery rate of SS recovery equipment. The SWU for combination use at 20 °C and 60 °C was higher than the SWU for single use. The SWU for combination use at 60 °C was higher than that at 20 °C. At 60 °C, combination use increased the SWU by 562 JPY/day (treatment amount 3,000 L/day) compared to single use, at 45% separation ability of the oil-water separation equipment according to the results of our filtration experiments.

The purpose of this study is to construct a home energy management system (HEMS) that uses information and communication technologies (ICT) and solar energy more effectively to reduce energy consumption without sacrificing comfort in houses at higher northern latitudes, i.e., in colder climates. The two core technologies of this system are a room environment control system that regulates temperature and illuminance only in the vicinity of the occupants by detecting them and a solar heating system that uses a ventilation heater that warms fresh air via stored solar energy. The aim of the former is to reduce energy consumption by not raising the average room temperature and illuminance. The aim of the latter is to improve the total efficiency of the solar heating system by increasing the efficiency of the input and output of the storage tank.

The Fischer-Tropsch synthesis (FTS) of syngas (34 vol% H₂, 16 vol% CO, and 50 vol% N₂) was carried out using cobalt-based catalysts in order to produce hydrocarbons (HCs) equivalent to kerosene, which is used as an alternative aviation fuel. The FTS had been conducted for a duration of 5 h in a downdraft continuous-flow-type fixed-bed reactor under a temperature of 230 °C and a pressure of 3.0 MPa. The effects of space velocity (W/F) and the chelator on the FTS were studied by focusing on primary kerosene yield and the carbon mass balance. In HCs with carbon numbers more than 6, the selectivity of CO to the HCs with carbon numbers of 11-14 equivalent to kerosene was found to be the second highest, the highest being its selectivity to HCs with carbon numbers of 6-10 equivalent to gasoline. The amount of primary kerosene produced was maximum under the W/F of 9 g h/mol. The addition of a chelator to a cobalt-based catalyst decreased the selectivity to CO₂. In the FTS with cobalt-based catalysts with the chelator of CyDTA, the selectivity of CO to the HCs with carbon numbers of 11-14 was found to be the highest.