Method for hybridized desalination system using membrane distillation and adsorption desalination cycles

A method for desalination of aqueous feed, the method comprising:

• a) providing a membrane distillation unit, the membrane distillation unit including a vapor permeable membrane and a high pressure side to one side of the membrane and a low pressure side to a side of the membrane opposite the high pressure side, the high pressure side having a higher vapor pressure relative to the low pressure side, the high pressure side having an aqueous feed liquid inlet and a liquid outlet, and the low pressure side having a permeate vapor outlet;
• b) providing a preheater having an aqueous feed inlet and an aqueous feed outlet, heating an aqueous feed liquid by the preheater and delivering the heated aqueous feed liquid into the high pressure side of the membrane distillation unit through the aqueous feed liquid inlet of the membrane distillation unit, the preheater having a heating fluid inlet and an outlet for heating fluid;
• c) passing aqueous vapor permeate from the high pressure side of the membrane distillation unit through the membrane to the low pressure side of the membrane distillation unit;
• d) providing an evaporator, the evaporator in communication with the liquid outlet of the membrane distillation unit, the evaporator having a fluid inlet configured to provide heat of evaporation to aqueous liquid in the evaporator received from the liquid outlet of the membrane distillation unit and a fluid outlet configured to discharge fluid from the evaporator, the evaporator having a vapor outlet for discharging vapor formed by evaporation of the aqueous liquid in the evaporator received from the aqueous liquid outlet of the membrane distillation unit, taking aqueous liquid from the high pressure side of the membrane distillation unit and supplying to the evaporator thereby evaporating at least a portion of the aqueous liquid to produce an aqueous vapor;
• e) providing at least one adsorption-desorption unit, the at least one adsorption-desorption unit having a vapor inlet configured to receive the aqueous vapor from the evaporation evaporator, each of the at least one adsorption-desorption unit including an adsorption-desorption bed, the at least one adsorption-desorption unit including a fluid inlet configured to receive either a heating or a cooling fluid and a fluid outlet, the adsorption-desorption unit having a vapor outlet, the adsorption-desorption unit further including a fluid inlet in communication with the fluid inlet of the adsorption-desorption bed, the adsorption-desorption unit including a fluid outlet in communication with the fluid outlet of the adsorption-desorption bed and in communication with the heating fluid inlet of the preheater;
• g) providing a condenser, the condenser including a condensation surface and a vapor inlet in communication with the permeate vapor outlet of the membrane distillation unit and the vapor outlet of the at least one adsorption-desorption unit, the vapor inlet of the condenser configured to deliver vapor from the membrane distillation unit and the at least one adsorption-desorption unit to the condensation surface, the condenser including a condensation outlet configured to remove condensate from the condenser, the condenser including a fluid inlet configured to deliver fluid from the evaporator to the condensation surface and to cool the condensation surface, and a fluid outlet configured to return the fluid from the condenser back to the evaporator and ultimately for return of the fluid to the fluid inlet of the condenser in a closed loop, taking the aqueous vapor that has been absorbed and desorbed by the at least one absorption-desorption unit and condensing the aqueous vapor by the condenser to produce a desalinated aqueous product and taking the aqueous vapor permeate from the low pressure side of the membrane distillation unit and condensing the aqueous vapor permeate by the condenser to produce aqueous product.