Integration of Process Modeling, Design, and Optimization with an Experimental Study of a Solar-Driven Humidification and Dehumidification Desalination System

Abstract

Solar energy is becoming a promising source of heat and power for electrical generation and desalination plants. In this work, an integrated study of modeling, optimization, and experimental work is undertaken for a parabolic trough concentrator combined with a humidification and dehumidification desalination unit. The objective is to study the design performance and economic feasibility of a solar-driven desalination system. The design involves the circulation of a closed loop of synthetic blend motor oil in the concentrators and the desalination unit heat input section. The air circulation in the humidification and dehumidification unit operates in a closed loop, where the circulating water runs during the daytime and requires only makeup feed water to maintain the humidifier water level. Energy losses are reduced by minimizing the waste of treated streams. The process is environmentally friendly, since no significant chemical treatment is required. Design, construction, and operation are performed, and the system is analyzed at different circulating oil and air flow rates to obtain the optimum operating conditions. A case study in Saudi Arabia is carried out. The study reveals unit capability of producing 24.31 kg/day at a circulating air rate of 0.0631 kg/s and oil circulation rate of 0.0983 kg/s. The tradeoff between productivity, gain output ratio, and production cost revealed a unit cost of 12.54 US$/m3. The impact of the circulating water temperature has been tracked and shown to positively influence the process productivity. At a high productivity rate, the humidifier efficiency was found to be 69.1%, and the thermal efficiency was determined to be 82.94%. The efficiency of the parabolic trough collectors improved with the closed loop oil circulation, and the highest performance was achieved from noon until 14:00 p.m.

A one-dimensional model for the motor oil-fuel dilution under gasoline engine boundary conditions

“…Oil layer and the mixing between the two fluids due to the lower viscosities at higher temperatures, the oil scrap is significantly lower because of the faster evaporation time with respect to the diffusion time-scale, as reported in [6]. Moreover, consistently with the small reduction of the average LSPI events observed in [18] when the oil grade turns from 0W-30 to 10W-30, the predicted oil scraps with the SAE 5W-30 (black curve) oil and the SAE 10W-30 oil (green curve, properties from [24]) are comparable. As visible in the red curves in Fig.…”

Recent progress in renewable energy based-desalination in the Middle East and North Africa MENA region

“… Low energy losses hence high system efficiency. 2018, [264] Solar Thermal, Flat plate collectors MD Jordan Experimental lab-scale study for SW desalination. 72 m 2 solar collector.…”

Special Issue on “Process Design, Integration, and Intensification”

“…In the work reported by Alghamdi et al [3], an integrated study of modeling, optimization, and experimental work was undertaken for a solar-driven humidification and dehumidification desalination system in Saudi Arabia. Design, construction, and operation are performed, and the system is analyzed at different circulating oil and air flow rates to obtain the optimum operating conditions.…”

“…Two works related to process design and integration were reported for simultaneous optimisation of water and energy usage in hydraulic fracturing [1], as well as the design of a palm oil milling process [2]. Besides, two works reported process intensification involving desalination unit [3] and reactive distillation [4].…”