Patent ID: 7389813

Claim:
A system for controlling the quality of gas delivered to a local environment comprising: a first temperature sensor to measure the temperature of a liquid entering a gas-liquid contactor; a second temperature sensor to measure the temperature of a gas exiting a gas heater; wherein the gas heater is connected to the contactor; wherein a liquid chiller is connected to the contactor; wherein the contactor comprises a countercurrent flow structure and has sufficient contact media surface area per unit volume to bring the gas and liquid to thermal equilibrium at full saturation; and a computer, comprising: an input means for a temperature set point and a relative humidity set point, a first compensator, a second compensator, a transformer taking the inputs of the temperature set point and relative humidity set point and generating an output to the second compensator, wherein the inputs to the first and second compensators further comprise signals from the second and first temperature sensors, respectively, wherein the first and second compensater outputs control the heater and chiller, respectively, to obtain gas from the contactor and the heater in a desired tolerance of the temperature and relative humidity set points.