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In this study, an air separation plant working according to the principle of separation of two columns and producing argon, nitrogen, and oxygen with a daily capacity of 250 tons was analyzed in detail with respect to the first and second laws of thermodynamics and the results were evaluated. The energy and exergy values for each point defined in the system were obtained. By using these values, thermodynamic evaluations for both the whole system and also its components were made. The efficiency values of energy and exergy, the values of energy losses and exergy destruction rates, the EIP (energetic improvement potential rate), ExIP (exergetic improvement potential rate), and the production of entropy values were found as 0.453, 0.79, 4368.475 kW, 10535.875 kW, 2391.535 kW, 3800.485 kW, and 35.347 kW/K, respectively. The energy and exergy efficiencies of the plant were found to be 45.3% and 13.1% respectively. [ABSTRACT FROM AUTHOR]

Removal of dyes from wastewaters causes a big concern from the environmental point of view due to their extreme toxicity towards aquatic life and humans. Commonly used traditional methods to treat these effluents are ineffective because dyes show resistance to many chemicals, oxidizing agents, and light. In this context, the biosorption process has attracted great attention in recent years since they utilize not only cheap plant materials but also a wide variety of microorganisms as biosorbing agents, displaying a high dye-binding capacity. In this study, biosorption potential of dried Penicillum restrictum (DPR) for Reactive Yellow 145 (RY 145) was studied with respect to pH, equilibrium time, and temperature to determine equilibrium and kinetic models. The most suitable pH and equilibrium time were determined as 1.0 ± 0.05 and 75 min respectively, at a biomass dosage of 0.4 mg L−1 and 20 ± 0.5°C. Data obtained from batch studies fitted well with the Dubinin-Radushkevich (D-R) followed by the Freundlich and Langmuir isotherm models. Maximum uptake capacities (qm) of DPR for the dyestuff (RY 145) were 109.7, 115.2, and 116.5 mg g−1 biomass at temperatures of 20, 30, and 40 ± 0.5°C, respectively. The overall biosorption process was best described by the pseudo-second-order kinetic model. Gibbs free energy changes were calculated as −384.6, −273.5, and −245.9 J mol L−1 at 20, 30, and 40 ± 0.5°C, respectively. [ABSTRACT FROM PUBLISHER]