Suitable Flowmeter for Citric Acid

A magnetic flowmeter should be suitable, for which there are dozens of manufacturers (ABB, Endress + Hauser, Siemens, etc. - other manufacturers are available). Check that the wetted parts are compatible with 10% citric acid solution by talking to suppliers before placing an order.

thanks! another colleague of mine also suggested the same thing.

"Great minds think alike and fools seldom differ." - Anon.

Ouch!

Agreed on the magmeter. With crystallization issues any sort of intrusive device like a paddle, float etc is liable to stick, & rotameters can be slowed. Ultrasonic or Coriolisis meters are fantastic but yet another step up in $$$$.

Is it possible to heat trace the line to the meter (practicality may depend on flow rate)?

That looks to be rotameter, A magnetic flow meter that was mentioned before is a good alternative. As long as it falls within your budget, they can be pricey.

Is there a reason why your flow meter is "wet"? If there is no specific reason why, then install a magnetic or an Ultrasonic/Doppler flow meter.

Another good source of flow meters of all types is Omega Engineering, though I do like E&H a lot:

http://www.omega.com/green/flow-level.html