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The chemical industry is acquiring new advancement day by day. Previously, quite massive equipment had been used to do heat transferring tasks, but now the industry has been modernised. Heat Integration is a trending area of study that might be applied in several sectors to redesign processes. Heat Integration alludes to any technique in chemical engineering that results in considerably smaller, greener, and more energy-efficient appliances. Heat Integration aims to improve energy transfer, lowering the equipment's capacity for heat transfer. This paper uses pinch analysis to optimize heat integration and find the best heat-exchange network through case studies. Pinch Technology offers a systematic approach to reducing energy use across all sites and activities. It is feasible to determine the proper alterations to the fundamental process parameters that can result in energy savings by using pinch technology. The Aspen Energy Analyzer tool has been used to compute the heat integration of the case studies. After obtaining the data from the software, they were used in pinch analysis to determine the optimal alternative for the heat exchanger network. [ABSTRACT FROM AUTHOR]

Sequestration of single heavy metal contaminant from industrial wastewater using pure bacterial strains has received much attention. However, application of a bacterial consortium in multiple metals sequestration is scarce. The present study was aimed to develop a consortium from three bacterial strains for the simultaneous sequestration of ternary metal ions (Cr6+, Cu2+ and Zn2+) from aqueous solution. Kinetic studies showed that the individual strain, Pseudomonas taiwanensis; Acinetobacter guillouiae and Klebsiella pneumoniae were able to remove Cr6+, Cu2+ and Zn2+ respectively. These bacterial strains were utilized to develop an indigenous consortium based on metal removal affinities and positive interferences between them. Consortium showed improved performance over individual strains for the removal of single as well as simultaneous removal of three metal ions. Fourier transform infrared (FTIR) spectral analysis showed the possible involvement of carboxyl, amino, hydroxyl, methyl, phosphate and sulphonate groups in metal ions sequestration. Consortium exhibits greater adaptability in ternary metal ions mixture which indicates its robust growth mechanism over individual bacterial strains. [ABSTRACT FROM AUTHOR]

In the present study, a laboratory-scale biofilter column was designed and fabricated. It was packed with a mixture of coal and compost as a packing medium. The column was enriched with an indigenous bacterial strainPseudomonas taiwanensisisolated from aerobic mixed culture of Sewage Treatment Plant, BITS-Pilani, Pilani campus. The removal of hexavalent chromium [Cr(VI)] from aqueous solution was investigated in the biofilter column. The entire biofiltration operation was divided into five phases (I to V) for a period of 63 days. Biofilter column was subjected to shock loading conditions for 20 days immediately after 63 days of operation. The maximum removal efficiency of 89.4% was obtained during phase V for Cr(VI) inlet concentration of 40 mg L−1. During shock loading, maximum removal efficiency was obtained as 90% for 48.5–50 mg L−1of initial Cr(VI) concentration. Kinetic parameters of biofiltration process for Cr(VI) removal were also determined by fitting Michaelis-Menten kinetic model with experimental data. The Michaelis-Menten kinetic constants were obtained as 0.258 mg L−1min−1and 26.83 mg L−1. It was found that Ottengraf-Van den Oever model with zero-order diffusion limitation fit the experimental data quite well for phases III, IV, and V with coefficient of determination (R2) values .97, .99, and .984, respectively. A possible method for safe disposal of packing medium was also presented in this study. [ABSTRACT FROM PUBLISHER]

An aerobic mixed culture collected in the form of activated sludge was enriched for Cr(VI) reduction. An indigenous microorganism was isolated from the enriched aerobic mixed culture and identified asPseudomonas taiwanensis. Bioremediation studies were carried out for treating Cr(VI)-contaminated wastewater using the indigenous microorganism. The kinetic studies were carried out for initial Cr(VI) concentrations ranging from 20 to 200 mg L−1. The maximum consumption of Cr(VI) obtained was 108.3 mg L−1for an initial Cr(VI) concentration of 150 mg L−1at a solution pH of 7.0. The effect of nutrient dosage and pH were studied to get their optimum values. The same isolated bacterial strain was also used to treat Cr(VI)-contaminated industrial wastewater collected from a local plating industry. Various growth kinetic models, such as Monod, Powell, Haldane, Luong, and Edward models, were fitted with the obtained experimental data. The obtained results for different growth kinetic models indicate that the growth kinetics ofPseudomonas taiwanensisfor bioremediation of Cr(VI) can be better understood by the Luong model (R2= .913). The rate kinetic analysis was performed using zero-order and three-half-order kinetic models. The three-half-order kinetic model was found to be suitable for the present bioremediation study. [ABSTRACT FROM AUTHOR]