Modeling and simulation of forward osmosis process using agent-based model system

Integration of capacitive deionization and forward osmosis for high water recovery and ultrapure water production: concept, modelling and performance analysis

Forward Osmosis (FO), a membrane desalination technology and Capacitive Deionization (CDI), an electrically operated desalination technology, are numerically integrated utilizing four different configurations for the high-water recovery rate and ultrapure water production from brackish water resource. To minimize the wastewater rejection, the CDI desorption stream is continuously fed to the FO unit, efficiently recovering the remaining freshwater. To produce ultrapure water, freshwater stream obtained from FO is provided to the CDI cell, which adsorbs the remaining dissolved solute particles. These two configurations serve the purpose of both industrial as well as domestic water supply requirements. Continuing this concept, the formation of the other two configurations allows us to obtain fresh water and ultrapure water simultaneously and up to a 90% freshwater recovery rate for the areas with inadequate supply. The performance parameters to assess the integration are the Water Recovery Rate (WRR) and Specific Energy Consumption (SEC). The first configuration (CDI-FO), proposed for a high freshwater recovery rate, resulted in 79.33% WRR with an SEC of 0.689 kWh / m 3 . While, for the second configuration (FO-CDI), 34.25% water was recovered as 2.87 ppm ultrapure water along with 34.25% freshwater. The third proposed configuration (CDI-FO-CDI) had a WRR of 79.33%, 14.67% of which was recovered as ultrapure water of concentration 2.86 ppm. The fourth configuration (CDI-FO-FO) developed for high water recovery, removed the maximum of water from the feed stream with a WRR of 91.33% and remained energy-efficient, consuming an SEC of 0.908kWh / m 3 .

Modeling and simulation of fertilizer drawn forward osmosis process using Aspen Plus-MATLAB model

Although experimental studies on the impact of feed (FS) and draw solutions (DS) on the forward osmosis (FO) applications are reported in literature, systematic mathematical modeling considering the dynamic change in solution properties is lacking. In this study, asymmetric FO membrane simulation model was established using Aspen Plus-MATLAB subroutines algorithm to account for the effect of concentration polarization (CP), types of FS and DS and in their properties on FO performance. The developed model was validated by comparing the simulation with experimental results. The model successfully predict the performance of FO process under wide varieties of operational conditions, FS and DS flow rates and concentrations. The model showed that the variation of MCFDS concentration had a marked effect on water flux (WF) in contrast to flow rate. The WFs obtained from seawater (SW) increased from 5.28 L/m².h to 42.08 L/m².h as MCFDS changes from 150 g/L to 300 g/L which corresponding to 11.66% to 45.33% of water recovery. As for synthetic aquaculture wastewater (SAWW), 9.70 L/m².h to 37.32 L/m².h of WFs were exhibited with the increase of MCFDS concentration from 50 g/L to 200 g/L, respectively. The effect of concentrated external CP (CECP) was found to be significant in case of SW and negligible with SAWW. Whereas, increasing MCFDS concentration increases the severity effect of dilutive internal CP (DICP). The degree of DICP depends on the solute resistivity (K_D) of porous layer, which were elevated (4.22-5.88 s/m) as MCFDS concentration increases (150-300 g/L). The study demonstrated the effectiveness and suitability of the developed Aspen Plus-MATLAB model simulating the FO process.