Abstract: A method for controlling the temperature of a coolant supplied to a process, such as a semiconductor process. The method provides for chilling a coolant to a predetermined temperature, controlling the coolant at the predetermined temperature and delivering the coolant to the semiconductor process. The method includes feedback and feed-forward control algorithms to control the temperature to within about ±0.1° C. under steady state conditions and to within about ±0.75° C. under maximum heat loading and unloading conditions. The invention may be used in any fluid or component temperature control application (e.g. semiconductor, pharmaceutical, or food applications).

Abstract: A process for separating oxygen and nitrogen using an adsorption system comprising at least one main adsorption vessel containing an adsorbent selective for one component and at least one auxiliary adsorption vessel containing an adsorbent selective for the same component, the auxiliary vessel(s) being operated under conditions which result in the production of a product gas of lower purity than the product gas from the main adsorption vessel(s). The lower purity product gas from the auxiliary vessel is used to purge or pressurize the main adsorption vessel(s).

Abstract: Oxygen of uniform purity is produced in a two-bed air-fed oxygen pressure swing adsorption process in which the beds are operated out of phase. The steps of the adsorption cycle include a pressurization/production step and a bed regeneration step, with the bed undergoing regeneration being purged with a low pressure stream of the oxygen-enriched gas produced as the nonadsorbed product of the process. The oxygen concentration in the purged gas effluent is continuously periodically monitored, and the maximum oxygen concentration in the effluent during selected purge steps is compared with the maximum oxygen concentration in the effluent during a previous purge step, and the difference is used to adjust the timing and duration of a purge step following the selected purge step in a manner that reduces the difference between the oxygen concentration in the sequential purge steps.