Abstract
This work aims to design a novel standalone small-size air-to-water pressure amplifier (ATWPA) for RO desalination system with low energy consumption. A small DC PV system, pneumatic system, and solar water heater were designed and used to operate the ATWPA at different air pressure (1–5 bar) and heating water (30–45 °C), hence avoiding using a high-pressure and high-energy water pump. The ATWPA has a smart electronic circuit with a feedback system and controls the IR to synchronize the piston movement with pressure and water discharge. The feed air pressure was maximized from 5 bar to 27.9 bar, i.e. the pressure has amplified by 458% where it creates enough pressure to overcome the membrane resistance. The power consumption of ATWPA varied from 0.0 to 3.5 W in compression and suction strokes, respectively and maximum energy consumption was 105 Wh. Increasing feed water temperature and operating air pressure led to increasing freshwater productivity. The preheating of saline water to 45 °C and increasing pressure to 5 bar increased freshwater productivity to 58.8 L/h and decreased energy consumption.
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•Design a novel air to water pressure amplifier (ATWPA) with performance evaluation.•Integration of ATWPA with solar water heating, RO membranes, and operated by a solar PV system.•A pneumatic system is used to provide the ATWPA with compressed air.•The designed ATWPA is an alternative to a high pressure-high energy consumption water pump.•The power consumption of ATWPA was taken from PV system in the suction stroke while zero in the compression stroke.