| 摘要 |
PURPOSE:To control a concn. of NaOCl in a specific range by a method wherein Cl ion remained in an absorbing liquid in a wet type deodorizing process is regenerated to NaOCl by electrolysis wherein convection voltammetry is employed in combination. CONSTITUTION:A malodorant gas 1 is sent to an absorbing tower 2 and, at first, an alkaline gas containing ammonia or the like is washed by an acid to be removed by adsorption. Subsequently, malodorant components based on sulfides such as hydrogen sulfide or methyl mercaptan is adsorbed and removed by an aqueous NaOCl containing solution to make the malodorant gas 1 odorless. The resulting NaOCl containing deodorizing liquid is sent to an electrolytic regeneration tank 10 from a recirculation line 6 by a bypass line 7 and residual Cl ion is regenerated to NaOCl by electrolysis. In this case, a NaOCl concn. in the deodorizing liquid is measured by a concn. measuring instrument 8 applying convection voltammetry and operation of a power source 11 of the electrolytic regeneration tank is controlled by the obtained measured signal 9 and the NaOCl concn. of the deodorizing liquid is always held to 0.001-0.5%. |
