Q1: Pick out the wrong statement:

ANS:D - Heat sensitive materials should be concentrated in high pressure evaporators.

The wrong statement is: Heat sensitive materials should be concentrated in high pressure evaporators. Explanation:

1. The capacity of an evaporator is reduced by the boiling point elevation: This statement is correct. Boiling point elevation refers to the increase in the boiling point of a solution compared to the pure solvent, which occurs when solute particles are added to the solvent. This elevation in boiling point reduces the driving force for evaporation, thereby decreasing the capacity of the evaporator.
2. Corrosive liquid is normally passed through the tubes in a shell and tube heat exchanger: This statement is generally true. In shell and tube heat exchangers, corrosive fluids are typically passed through the tubes, which are easier to clean and maintain compared to the shell side. This arrangement helps to protect the shell from corrosion.
3. Steam jet ejector is used for vapor compression in a thermal recompression evaporator: This statement is correct. A steam jet ejector is a device used to create a vacuum by entraining and compressing vapor using steam. In a thermal recompression evaporator, steam jet ejectors are often employed to compress the vapor generated during evaporation, thereby increasing the driving force for evaporation and improving efficiency.
4. Heat sensitive materials should be concentrated in high-pressure evaporators: This statement is incorrect. Heat-sensitive materials are typically concentrated in low-pressure evaporators to minimize the risk of thermal degradation or other adverse reactions. High-pressure evaporators operate at higher temperatures, which can increase the risk of heat damage to sensitive materials. Therefore, low-pressure evaporators are preferred for concentrating heat-sensitive materials.