Weak black liquor 15% 10 tons Evaporated water 7.5 tons Evaporation Strong black liquor 60% 2.5 tons A diagram above illustrates a lot of water evaporated from weak black liquor after pulp washing. For a better evaporation efficiency, "Multiple effect" evaporation is used. Give a detailed process description of multi effect evaporation. 

 

Weak black liquor 15% 10 tons Evaporated water 7.5 tons Evaporation Strong black liquor 60% 2.5 tons A diagram above illustrates a lot of water evaporated from weak black liquor after pulp washing. For a better evaporation efficiency, "Multiple effect" evaporation is used. Give a detailed process description of multi effect evaporation. (10)