Heat powered water pump for reverse osmosis desalination

Abstract

Current desalination techniques are typically very energy intensive: energy consumption can account for up to 70% of the desalination costs. To improve economics of water desalination plants innovative energy efficient, inexpensive, water pump powered by heat is proposed. The technology is an alternative to the reverse osmosis water desalination processes. It eliminates electricity consumption and the high-pressure pumps and permits improvements in the energy recovery. Instead of the use of positive displacement (plunger) pumps the pumped fluids (water) are compressed directly by heat in the heat driven pumps (or compressors) and the energy of the working fluid is directly transmitted to a liquid to be pumped. The pump can be powered by any source of heat, e.g. solar, geothermal, waste, combustion. A substantial improvement of the economics of the reverse osmosis processes is expected due to the use of renewable energy, considerable decrease of capital cost, increased energy conversion efficiency and reduced maintenance cost.