A triple effect standard vertical tube evaporator each effect of which has 140 m² of heating surface is to be used to concentrate from 5 % solids to 40% solids a solution possessing a negligible boiling point elevation. Forward feed is to be used. Steam is available at 120°C, and the vacuum in the last effect corresponds to a boiling temperature of 40°C. The overall coefficients in W/m²·°C are 2950 in I, 2670 in II and 1360 in III, all specific heats may be taken as 4.2J/g°C, and radiation is negligible. Condensates leave at condensing temperature. The feed enters at 90°C. Calculate

(a) The kilograms of 5% liquor that can be concentrated per hour,

(b) The steam consumption in kilograms per hour.