GB767552A - Improvements in or relating to apparatus for dispensing chlorine dioxide - Google Patents

Abstract

An apparatus for the production of a gaseous mixture of chlorine dioxide and an inert gas by dissolving chlorine dioxide hydrate in water and stripping chlorine dioxide from the solution by means of inert gas, comprises a mixing vessel 1 for chlorine dioxide hydrate and water, a storage vessel 23, a pipe 22 for intermittently passing batches of the solution formed in the mixing vessel to the storage vessel, a constant level standpipe 35, a pipe 32 for passing solution continuously from the storage vessel to the standpipe, a pipe 36 for returning solution by an overflow to the storage vessel, a stripping tower 40, a pipe 37 including a flow control device 38 and a flowmeter 39 for passing the solution continuously from the standpipe to the stripping tower, a pipe 50 for introducing inert gas into the bottom of the stripping tower counter - current to solution flowing therethrough to form a dilute mixture of chlorine dioxide and inert gas and a pipe 52 for adding additional inert gas of lesser humidity to the gaseous mixture emerging from the top of the stripping tower. The mixing vessel 1 may have a float 8 or false lid (Fig. 2, not shown) substantially completely covering the surface of the solution contained therein. The storage vessel 23 may have a similar float 24. As shown, flow of solution from standpipe to stripper is effected by the application of inert gas under pressure from pipe 41. Alter <PICT:0767552/III/1> natively gravity flow may be employed. A slightly reduced pressure may be maintained in the mixing and storage vessels by connection via pipes 28 and 10 with a vent tower 59 from which gas is withdrawn through pipe 58. Spent solution from stripper 40 passes through pipe 60, is admixed with overflow solution from mixing vessel 1, pipe 10, vent tower 59 and pipe 61 and then passes to waste through trap 63, which is vented either to the vent tower via pipe 65 (as shown) or to the atmosphere and pipe 64. Specification 742,898 is referred to.