GB301213A - Improvements in and relating to condensate removing systems - Google Patents

Abstract

301,213. Irving, R. Bell-, and Sand well, R. Dec. 9, 1927. Drying. - The main condensate outlet of a steam chamber, such as a rotary paper drier, is continuously sealed by the condensate and is normally closed, there being means for opening the main outlet in response to an initial discharge of condensate through an auxiliary outlet. fig. 1 shows one form of apparatus applied to a rotary paper-drying drum 1, to which steam is supplied through the hollow shaft 2 from a header 6. Extending through the shaft 2 and terminating adjacent the bottom of the drum are main and auxiliary condensate discharge pipes 7, 14 respectively, the former being connected by a pipe 9 and through a normally closed valve 10 to a condensate discharge header 13. The pipe 14 is connected to a chamber 18 containing a bucket 21, which is normally maintained floating in the position shown. When the condensate in the drum 1 reaches the end 16 of the pipe 14 it passes up this pipe into the chamber 18, and overflows into and sinks the bucket 21, which through a lever 23 opens a valve 24 and allows liquid to pass from the bucket, through a centre tube 21<1> and pipe 26, to the upper side of a diaphragm 29, which is thus depressed to open the main condensate discharge valve 10. When the fall of the condensate level in the drum 1 uncovers the end of the pipe 14 steam passes up this pipe and forces the condensate from the bucket 21, and the parts return to the position shown, the condensate above the diaphragm 29 being forced out through a choke coil 28 by a counterweight 11. When the end of the pipe 14 is not covered by the condensate steam and accumulated air pass up it to the chamber 18, which is connected to the header 13 through a choke coil 19 which limits the flow. A modification is described in which the space below the diaphragm is in communication with an auxiliary or the main condensate header, instead of with the atmosphere, thus enabling the apparatus to be used whether the dryer pressure is above or below that of the atmosphere. Fig. 3 shows a further modification, in which the condensate passing up the pipe 14 accumulates in a vertical pipe 35 and so produces a head pressure on the diaphragm 29, which is thus caused to open the condensate discharge valve 10. When the condensate level falls, steam passes up the pipe 14 and forces the condensate from the pipe 35 into the surrounding chamber 36, from which it passes to the header 32, the valve 10 being then closed by a counterweight 11. The application of the system to the drying portion of a paper machine is illustrated, the drying drums being in two series, and the condensate from the first being discharged into a low-pressure receiver and used to produce flash steam for heating the second series, the condensate header of which is maintained under a vacuum. Specification 28162/96, [Class 64, Heating], is referred to.