Heat Exchanger / After Cooler for Blower

The temperature seems high for such a low pressure, what is the source of the makeup air? What is the air used for? Is the client looking for humidity reduction as well?

He didn't give the in/out temperatures, only the reduction.

That might be roughly inferred, though. Say tap water 20ºC, approach say 5º = 25º, reduction of 71ºC = 96ºC initially.

I just meant we can't judge the discharge temperature as high if we haven't been given it, only the desired reduction over the cooler.

For those sorts of flow (presumably 2 different systems) it's likely to be Roots blowers, and from my data for 3500 m³/h and 700 mbar pressure rise, temperature rise is ~ 70°C. More data needed on the cooling water temperature and flow available to design a cooler, whichever type OP goes for.

hi,

yes the application is for Roots Blower Discharge air cooling.

Outlet temp. of Roots Blower air is 120 Deg.C. Desired temp. after cooling is 50 Deg. C.

Inlet Water available for cooling at 30 Deg. C.

Cooling water is to be supplied through water pump for necessary flow requirements.

My primary guess is @ 80 -90 lpm for @ 3500 air flow.

And @ 150 lpm for 8600 air flow. considering CS tube material for Exchanger.

You need to asked why shell and tube? I’ve design regenerator for hot gases, using 2” shell and tube, but that deals with a higher flow rates... as well as plate heat exchangers.

The flow rate you have, a dimple plate heat exchanger would do the job being more efficient and cost effective.

What is the air quality passing through it? Is it dirty exhaust with high particulates?

hi,

air passing is atmospheric air after filtration.

If your client is insisting on shell-and-tube then you don’t have any options, Mildred. Simply provide your client with whatever he is prepared to pay for, and stop arguing with yourself and others. All that does is waste everybody’s time.

yes. exactly... i am doing the same now