Brine management in desalination industry: From waste to resources generation

Desalination and environment: A critical analysis of impacts, mitigation strategies, and greener desalination technologies

An overview of brine management: Emerging desalination technologies, life cycle assessment, and metal recovery methodologies.

The treatment of tannery effluent is of great interest as it contains a complex mixture of pollutants, primarily chromium. The disposal of this wastewater can have adverse effects on the environment and aquatic life, which is an emerging problem for the environment. In this work, electrocoagulation is used to remove chromium from real tannery wastewater, focusing on performance optimization and sludge characterization. Electrocoagulation experiments were conducted using an electrochemical cell with iron electrodes immersed in a specific volume of tannery wastewater. Operating parameters, such as the initial chromium concentration, pH and current density as well as power consumption were evaluated to determine optimum chromium removal. The optimization was performed using Response Surface Methodology combined with central composite design. Analysis of variance (ANOVA) was used to determine the response, residual, probability, 3D surface and contour plots. The maximum chromium removal was 100% at the optimum values of 13 mA/cm2, 7 and 750 ppm for current density, pH and concentration, respectively.

Chromium Removal from Tannery Wastewater by Electrocoagulation: Optimization and Sludge Characterization

A new process for the capture of CO2 and reduction of water salinity

In this work, the recovery of magnesium from desalination reject brine through reaction with ammonia has been evaluated and statistically optimized using response surface methodology. The process is based on precipitation of magnesium hydroxide by the reaction of MgCO3 in the brine with ammonium hydroxide. A software, which is designed for studying chemical reaction and equilibrium, was employed to perform the thermodynamic analysis of the reaction of magnesium carbonate with ammonia, which was found to be exothermic and spontaneous in the temperature range of 0–22 °C. Central composite design (5-level, 3-factor) was used to optimize the process to obtain the maximum response of magnesium recovery as a function of reaction temperature, brine salinity, and ammonia to magnesium molar ratio. Maximum recovery of 99% was obtained at a temperature of 15 °C, brine salinity of 85 g/L, and a molar ratio of 4.4NH3: 1 Mg. The predicted response was in excellent agreement with the experimental results. The collected solid product at optimum conditions was characterized using X-ray Diffraction, Energy Dispersive Spectra analysis and thermogravimetric analysis. The analysis indicated the high purity of the recovered product in the form of Brucite (Mg(OH)2).

Optimization of magnesium recovery from reject brine for reuse in desalination post-treatment

The present work optimizes the CO2 capture based on the Solvay process, where carbon dioxide is passed into ammoniated brine and reacts with sodium chloride to form a precipitate of sodium bicarbonate and a soluble ammonium chloride. The process has the dual benefit of decreasing sodium concentration in the reject brine and reducing carbon dioxide emissions to the atmosphere. Process parameters were studied in a semi-batch reactor to determine their effect on CO2 capture efficiency and ions removal. The optimum conditions for maximum CO2 capture efficiency and ions removal have been determined using response surface methodology. The optimum CO2 capture efficiency and ions removal was found to be at temperature of about 19 C, a gas flow rate of 1.54 L/min, and a molar ratio of 3.3NH3:1NaCl. The CO2 capture efficiency in 180 min was equal to 86% and the maximum sodium removal was 33%. These results indicated the technical feasibility of the Solvay approach for the capture of CO2 through reactions with desalination reject brine.

/pdf/optimization-of-a-solvay-based-approach-for-co2-capture-57y75u2g4p.pdf

Ameera F. Mohammad

Papers

A new process for the capture of CO2 and reduction of water salinity

Optimization of magnesium recovery from reject brine for reuse in desalination post-treatment

Optimization of a Solvay-Based Approach for CO2 Capture

Effects of potassium hydroxide and aluminum oxide on the performance of a modified solvay process for CO2 capture: A comparative study

Evaluation of a novel gas-liquid contactor/reactor system for natural gas applications