Reaction furnace WHB w/ SD: downcomer nozzle location

[Pete]

Some design show downcomer nozzles inline to WHB vertical centerline at the bottom of boiler. Other design it angled to vertical centerline at the bottom quadrants of WHB. What are the main advantage between this two configurations. When they are being applied or considered?

I have a requirements to provide inttermittent blowdown nozzles at the bottom of WHB inline to vertical centerline. Is the first case above applicable with the intention of providing this intermittent nozzles?

[saplanti]

It might be too late, but I have just wanted to reply this.

I do not know the configuration of the furnace that you are talking about. However, everything is hidden in the supporting system of the furnace walls and drums. Think about the differantial vertical thermal of the walls and the downcomer(s). I guess downcomer liquid temperature is lower than the wall temperature in your design. So, you might want some flexibility in the system to compansate the differantial temperature between these two.

I trust this is sufficient, you may guess the following.

Hope it helps.

[saplanti]

The third sentence was suppose to be the following:

"Think about the differantial vertical thermal MOVEMENT of the walls and the downcomer(s). "

Regards.

[saplanti]

The second correction. I beg your pardon.

"Think about the differantial vertical thermal EXPANSION of the walls and the downcomer(s). "

Regards.