Chlorine dioxide generating system

Claim 1

A chlorine dioxide generating system for treating a process with chlorine dioxide that is substantially free of chlorine comprising: A. a reactor having two inlets and an outlet, the reactor being constituted by a vertically-positioned packed column, said inlets being at the bottom and said outlet being at the top of the column; B. a supply of aqueous sodium chlorite coupled to one inlet of the reactor; C. an unpressurized supply of chlorine gas coupled to the other inlet of the reactor whereby gas is drawn into the reactor only when a negative pressure exists therein, the chlorine reacting with the sodium chlorite to generate chlorine dioxide; D. an ejector coupled to the outlet of said reactor and operated by a stream of water to produce a vacuum drawing chlorine dioxide from the reactor into the ejector to intermingle with the water stream, whereby the ejector discharges a dilute solution of chlorine dioxide for feeding to the process to be treated, the resultant negative pressure in the reactor drawing chlorine gas therein; and E. a vacuum regulator interposed between the other inlet to the reactor and the chlorine gas supply to effectively disconnect said supply from said reactor in the absence of a negative pressure therein, said regulator supplying chlorine gas at a predetermined constant flow rate to the reactor within a range of negative pressure values, said predetermined constant flow rate being independent of the negative pressure value.