Fresh milk at 100C is to be pasteurised at 800C in a counter-current flow heat exchanger. The milk flows into the exchanger at a volumetric rate of 1.5 x10-3 m3s-1. Hot water at 900C, flowing at 1.4 x10-3 m3 s-1 is used as the source of heat. (i) Find the rate of heat transfer to bring the cold milk to pasteurisation temperature . The hot milk exiting the exchanger at 800C is to be cooled to 250C. For economic reasons, the pasteurised hot milk will be pre-cooled by using it to is to pre-heat an incoming stream of cold fresh milk (inlet at 100C). This practice is termed heat regeneration. 75% of the heat content of hot milk is used in this way. Both hot and cold streams of milk flow at 1.5x10-3 m3s-1. (ii) Calculate the rate of heat loss by the hot milk to cool to 250C (iii) Determine the exit temperature of pre-heated cold milk (iv) Calculate the extra heat needed to raise the temperature of the pre-heated milk to the pasteurisation temperature of 800C (this extra heat is to be supplied by hot water) (v) Hence, determine the % saving on heat by employing heat regeneration. (vi) What conclusion can you draw from your result from (v)?