Q1: In regenerative air preheater (as practised in heating of coke ovens), the heat is transferred

ANS:C - by heating an intermediate material (like chequor bricks) and then heating the air from this hot material.

In a regenerative air preheater, such as those used in heating coke ovens, the heat is transferred: c) by heating an intermediate material (like chequor bricks) and then heating the air from this hot material. Regenerative air preheaters typically employ a regenerative heat exchange process. They consist of a matrix of heat-absorbing materials, such as bricks or ceramic elements, arranged within the preheater chamber. The hot flue gases from the furnace pass through one side of the preheater, transferring heat to the bricks or ceramic elements. Then, during the next phase of operation, air for combustion or other processes is passed through the same chamber, where it absorbs heat from the previously heated bricks or ceramic elements before entering the furnace. This cycle repeats periodically, allowing for efficient heat exchange between the hot flue gases and the incoming air.