The Energy and Exergy Analysis of the Reactor Unit of Boric Acid Production Process with ChemCAD Simulation

Energy and exergy analysis of systems are of great importance to enhance the energy and exergy efficiency of industrial production facilities. With the energy and exergy analyses performed, the energy dependency of the production facilities and their energy consumption can be reduced, the price of the product can decrease, and the profit margin can increase. Additionally, it is ensured that the energy produced based on fossil fuels is used in a controlled way. In the present study, the analysis of energy and exergy has been performed for the production reactor unit of the Boric Acid from Colemanite. The first law of thermodynamics and ChemCAD simulation program was used for energy analysis calculations, and the calculations of exergy analysis were carried out by using the second law of thermodynamics. The total energy loss of the reactor unit and the calculated energy loss per 100 kcal input steam were calculated as 110880 kcal/h and 3.724%, and the losses of total exergy in the reactor units and the losses of exergy calculated per 100 kcal input steam were calculated as 225058.86 kcal/h and 30.095%, respectively. Exergy efficiency for the reactor unit has been determined as 3.3 %. Some suggestions were given for the reactor units of boric acid production plants to minimize system losses.

Performance Evaluation of a Full-Scale Fused Magnesia Furnace for MgO Production Based on Energy and Exergy Analysis

A three-electrode alternating current fused magnesia furnace (AFMF) with advanced control technology was evaluated by combined energy and exergy analysis. To gain insight into the mass flow, energy flow and exergy efficiency of the present fused magnesia furnace, the exergy destruction was analysed to study the energy irreversibility of the furnace. Two different production processes, the magnesite ore smelting process (MOP) and light-calcined magnesia process (LMP), are discussed separately. Two methods were carried out to improve LMP and MOP; one of which has been applied in factories. The equipment consists of an electric power supply system, a light-calcined system and a three-electrode fused magnesia furnace. All parameters were tested or calculated based on the data investigated in industrial factories. The calculation results showed that for LMP and MOP, the mass transport efficiencies were 16.6% and 38.3%, the energy efficiencies were 62.2% and 65.5%, and the exergy destructions were 70.5% and 48.4%, respectively. Additionally, the energy efficiency and exergy efficiency of the preparation process of LMP were 39.4% and 35.6%, respectively. After the production system was improved, the mass transport efficiency, energy efficiency and exergy destruction were determined.