Diffusion driven desalination apparatus and process

A power plant including a desalination system, comprising:

• an apparatus for converting a source of energy into a heated water stream, said heated water stream including at least one salt;
• a diffusion tower for creating regions having thin films of water from said heated water stream;
• structure for forcing a low humidity air stream over said thin film of water, wherein water prom said thin film of water evaporates and diffuses into said low humidity air stream to create a humidified air stream, 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 water stream including at least one non-volatile impurity, said heated water stream having a temperature above an ambient temperature;
• spraying said heated water stream onto a high surface area material, wherein thin films of water form on surfaces of said high surface area material;
• forcing a low humidity air stream over said thin films of water, wherein water from said thin films of water evaporate and diffuse into said low humidity air stream to create a humidified air stream, and
• direct contact condensing said humidified air stream wherein purified water is produced.

A diffusion tower for humidifying air, comprising:

• a rigid outer shell, an inside volume of said shell including a portion filled with high surface area material;
• at least one inlet for receiving a heated water stream, wherein at least one region having a thin film of water forms on said high surface area material;
• at least one inlet for receiving a low humidity air stream, wherein said low humidity air stream is forced over said region having a thin film of water, wherein water from said thin film evaporates and diffuses into said air stream to create a humidified air stream, and
• at least one plenum separator disposed within said inside volume of said shell and above a height of said inlet for receiving said heated water stream, said plenum separator including an upward facing structure for drawing said humidified air stream out from said diffusion tower and preventing said hot water from said hot water stream from being drawn out.