QUESTION 5 Dumela steam boiler plant situated in the Eastern Cape, consists of an economiser, evaporator and superheater. Steam is generated at 3.1 kg/s at a pressure of 4 000 kPa and 455°C. The feed water enters the economizer at 40°C and the boiler at 85°C. The steam leaves the evaporator 94% dry The plant uses 800 kg coal/hour with a calorific value of 47 MJ/kg. 5.1. The heat transfer in the economiser 5.2. The heat transfer in the evaporator 5.3 The heat transfer in the superheater. 5.4. The plant efficiency 5.5 Interpret the answer obtained in question 54 (3) (4) (3) (3) (2)