Diffusion driven water purification apparatus and process

A power plant including a water purification system, comprising:

• an apparatus for converting a source of energy into electrical energy and providing waste heat;
• a heat exchanger for heating an air stream to form a heated air stream using said waste heat;
• said heated air stream having a temperature above an ambient temperature;
• at least one water heating structure for receiving a source water stream including at least one impurity to be purified and outputting a heated water stream which has a temperature above 30° C.;
• a diffusion tower having high surface area material therein coupled to receive said heated air stream and said heated water stream, said diffusion tower creating at least one region having thin films of heated water therein from said heated water stream and having structure for directing said heated air stream over said thin films of heated water to create a humidified air stream that is at least substantially saturated;
• and
• at least one direct contact condenser in fluid communication with said humidified air stream for condensing said humidified air stream, wherein purified water is produced.

A method for purifying water, comprising the steps of

• providing a heated air stream, said heated air stream having a temperature above an ambient temperature;
• providing a heated water stream from a received source water stream including at least one non-volatile impurity, said heated water stream having a temperature above 30° C.;
• spraying said heated water stream into a diffusion tower having a high surface area material therein, wherein thin films of water form on surfaces of said high surface area material;
• forcing said heated air stream over said thin films of water, wherein water from said thin films of water evaporate and diffuse into said air stream to create a humidified air stream that is at least substantially saturated;
• and
• direct contact condensing said humidified air stream, wherein purified water is produced.