In this study, first and second law thermodynamic analyses were performed for HDH systems based on the enthalpy pinch methods for basic HDH configurations with extraction and injection, and on the enthalpy pinch and effectiveness methods for hybrid HDH-HP systems, using MATLAB software. To calculate the enthalpy pinch, a new algorithm is proposed to calculate the enthalpy pinch in the humidifier by accounting variations in salinity and saline water flow rate within the humidifier. For HDH-HP systems, two novel (single-stage and two-stage) configurations are proposed in this research. Subsequently, first and second law thermodynamic analyses were conducted for the basic HDH systems with extraction and injection using the proposed enthalpy pinch method, and the results for GOR and entropy generation were reported. The results indicate that applying the proposed method for calculating the enthalpy pinch of the humidifier leads to a significant increase in the predicted GOR for HDH systems with and without extraction and injection. This increase is particularly notable at lower values of enthalpy pinch. For example, in the case of three extractions and injections at zero enthalpy pinch, the predicted GOR obtained in the present study shows a 23% increase compared to previous studies.
Furthermore, a comprehensive thermodynamic analysis of the proposed HDH-HP systems was carried out using the effectiveness and enthalpy pinch approaches, aiming to investigate the sensitivity of these systems to the main operating parameters. In both the single-stage and two-stage systems, decreasing the condenser saturation temperature or increasing the evaporator saturation temperature results an increase in GOR. Compared to the effects of other parameters in single-stage HDH-HP, the mentioned parameters have greater effect on GOR of the system. Specifically, a 3°C change in either of these two parameters leads to a 10% increase in the single-stage HDH-HP system GOR. In contrast, the most