Method of and apparatus for treating waste gas from semiconductor manufacturing process

A method of treating waste gas, comprising the steps of:

• providing a reaction chamber, a container housing a dry solid absorbent, inlet conduit means providing gas communication between said reaction chamber and said dry solid absorbent in said container, exit conduit means providing gas communication between said dry solid absorbent in said container and the atmosphere, and evacuation device disposed between said reaction chamber and said inlet conduit means, said evacuation device providing gas communication between said reaction chamber and said inlet conduit means and adapted to force gas flow from said reaction chamber to said inlet conduit means, bypass conduit means providing gas communication between said inlet conduit means and said exit conduit means, and a bypass valve for closing said bypass conduit means;
• flowing waste gas from said reaction chamber through said evacuation device, said inlet conduit means, said dry solid absorbent in said container and said exit conduit means to the atmosphere with said bypass valve closed;
• introducing a first inert purge gas into said reaction chamber for a period of time sufficient to purge said reaction chamber of the waste gas;
• introducing a second inert purge gas into said evacuation device for a period of time sufficient to purge the waste gas from said evacuation device, said inlet conduit means and at least a portion of said bypass conduit means;
• and
• venting a large amount of gas from the reaction chamber to the atmosphere with said bypass valve open, the gas venting through said evacuation device, said inlet conduit means, both said dry solid absorbent in said container and said bypass conduit means, and said exit conduit means.