of wash liquor with dissolved solids out of the reaction chamber at 19 be lr the ratio of these two flows is an important determinant of the flash tank pressures so define r wr lr values for wr lr and r must be calculated from the operational requirements of the process application thus start with the feed rate of solid material its temperature and its composition consider the steam flow required to heat to operating temperature consider the portion of the feed that will be dissolved consider the moisture content of the solids to be discharged and consider the allowable concentration of dissolved solids in the effluent wash liquor with knowledge of the heat capacities of the various materials and by use of a set of steam tables the necessary calculations can be performed for fresh sawmill waste in the pacific northwest the result will be r 0 8 more or less for initial process design purposes an approximate calculation can be done to determine stage temperatures and mass flows consider the liquid flow lr at temperature tr with enthalpy hr at 19 in fig3 this liquid is to be cooled to temperature t3 and enthalpy h3 in flash tank ft3 57 the enthalpy change will be lr hr u2212 h3 this excess heat will flash part of the liquid to steam with an enthalpy change from liquid to vapor given by f3 hiv3 lr hr u2212 h3 where f3 is the rate of steam flow at 56 this flash steam will pass to the.