The Study Of Water Level Control In Direct-Heated Solar Desalination System

Seawater desalination is very effective for the reason of fresh water resources shortage.However the traditional seawater desalination technology consumes conventional energy,such as oil, coal and other fossil fuels. It leds to lower development of the seawaterdesalination technology and the conventional energy not only is non-renewable resources butalso influence the environment. Solar energy has already presented its advantage due toexcessive energy consumption and ecological environment deterioration, solar energy don’tconsume conventional energy and don’t produce secondary pollution, so solar energyseawater desalination becomes one of the important ways for seawater desolation.Solar seawater desolation has got certain development in recent years, and distillationmethod is one of the most common one. In the seawater desalination system, solar andseawater desalination is basically separation, the seawater indirectly gets heat from solarsystem through the heat exchanger. In direct-heated solar desalination system, input seawaterdirectly heats from solar heating device, effectively avoids unnecessary heat loss.Due to the direct-heated solar seawater desolation combines the flash method andlow-temperature multi effect and low-temperature multi effect evaporator adopted the methodof heat immerses so the effect of the first level control is very important. The water control ofsoaking type is discussed in this paper. The water level control object of the evaporator hasmany disturbances and it increases a disturbance quantity than the traditional boiler waterlevel control object. So it makes the object properties more complex. By comparing we find amore suitable way for the control method of the water level control in direct-heated solardesolation system.