Dynamic Modeling and Preliminary Performance Analysis of a New Solar Thermal Reverse Osmosis Desalination Process

Abstract

Reverse osmosis (RO) is a desalination technique that is commonly preferred because of its low energy consumption. In this paper, an innovative, thermally powered RO desalination process is presented. This new thermo-hydraulic process uses solar thermal energy in order to realize the pressurization of the saltwater beyond its osmotic pressure to allow its desalination. This pressurization is enabled thanks to a piston or a membrane set in motion in a reservoir by a working fluid that follows a thermodynamic cycle similar to an Organic Rankine Cycle. In this cycle, the evaporator is heated by low-grade heat, such as the one delivered by flat-plate solar collectors, while the condenser is cooled by the saltwater to be treated. Such an installation, designed for small-scale (1 to 10 m3·day−1) brackish water desalination, should enable an average daily production of 500 L of drinkable water per m² of solar collectors with a specific thermal energy consumption of about 6 kWhth·m−3. A dynamic modeling of the whole process has been developed in order to study its dynamic cyclic operating behavior under variable solar thermal power, to optimize its design, and to maximize its performances. This paper presents the preliminary performance results of such a solar-driven desalination process.

Design and Energy Consumption Analysis of Small Reverse Osmosis Seawater Desalination Equipment

“…The author used a genetic-simulated annealing algorithm to numerically solve the model and found that a robust scheduling scheme can optimize the reverse osmosis system better than a static scheduling scheme. In 2019, Lacroix [12] introduced a new type of thermal power reverse osmosis desalination process. This new thermal hydraulic process used solar energy to pressurize sea water and made it exceed osmotic pressure, to desalinate it.…”

Enhancement of Continuous-Feed Low-Cost Solar Distiller: Effects of Various Fin Designs

“…Solar water distilling devices are classified into several models-e.g., prism models, pyramid models, and centralized collector models [8]. Nevertheless, these devices cannot produce large amounts of distilled water, as reported by Badran [2], Heck et al [6], Cappelletti [9], and Aburideh et al [10]. Cappelletti [9] performed an experimental study on a plastic solar still and obtained 1.7-1.8 L/d of distilled water.…”

“…Energies 2021, 14, 4844 2 of 15 Meanwhile, a powerful device to turn seawater into freshwater is RO. This kind of device has been also investigated by previous researchers [4][5][6][7].…”

A Separation and Desalination Process for Farmland Saline-Alkaline Water

“…In 2019, Sun et al [26] performed a two-phase flow test on a circulating solar collector tube at the Zijingang Campus of Zhejiang University, and assembled the collector tube by means of horizontal series connections to simulate the heat-collecting efficiency of the collector tube at different flow velocities. Lacroix et al [27] introduced a new type of thermal power reverse osmosis desalination process. This new thermal hydraulic process used solar energy to pressurize sea water and made it exceed osmotic pressure, to desalinate it.…”