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Flow meter

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MilanMhatre

Chemical
May 20, 2013
18
Does anyone have info about flow meter which have input "WHAT VOLUME WE NEED TO FEED IN BATCH REACTOR " ???

e.g. i need 100kg or 100m3 is set point on meter , after feeding fluid supply pump auto stop.

pl do needful ( provide link for proper deal)
 
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MilanMhatre,
I am having difficult determining what your question is. If you are having difficulties with the language, you might go to forum1529 and ask the question in your native language and see if the helpful people over there can help you put it into a form that will lead to the answer to the question you are asking.

David Simpson, PE
MuleShoe Engineering

"Belief" is the acceptance of an hypotheses in the absence of data.
"Prejudice" is having an opinion not supported by the preponderance of the data.
"Knowledge" is only found through the accumulation and analysis of data.
The plural of anecdote is not "data"
 
Simple question is...
i need info about flow meter.... which has future of measuring mass of fluid required ....

e.g. if i need batch of 100kg fluid, then on flow meter i will set 100kg . that much liquid should discharge by pump.

Understood dear??
 
I am not sure what part of the world you are in.

We normally do this with load cells beneath the receiving tank. Measure weight as it fills, and turn off the supply at a time that allows the fluid still in the pipe downstream of the valve to complete the batch load. This correction we call in-flight adjustment.

I do not know of a flow controller that will do this as a stand-alone device in the way that you want to use it. I would have a PLC monitor the flow transmitter and take the action to start and stop flow to achieve the batch weight. Note that you will still need to account for in-flight quantities downstream of your valve.

I have installed one similar system in the US in a case where load cells are not feasible. There are manufacturers of totalizing flow transmitters such as Data Industrial, Flowline, Fluidyne, Thermo Scientific.

Best to you,

Goober Dave

Haven't see the forum policies? Do so now: Forum Policies
 
To get the right flow meter for this "batching system" will require more information than provided with this simple-minded approach. Currently, it would be only a guess. If you can provide some pertinent details, you may get a good answer. If you don't know what details are important, ask.

Good luck,
Latexman

Need help writing a question or understanding a reply? forum1529
 
Correolis meters measure mass very accurately directly due to their design of a vibrating tube. There are many vendors, just search for them.

You would need a small PLC to start and stop your delivery system, but again there are many vendors able to supply a total package. What you describe is similar to a tanker loading system where so long as you want to measure volume and not mass, you can just punch figueres into a meter head and it will count down and stop flow automatically. Try someone like veeder root -
My motto: Learn something new every day

Also: There's usually a good reason why everyone does it that way
 
Yes correct, flowmeter. Flow meter output gives flow rate. Send output to control system totalize. When sum=target control system turns off pump or closes valve. In place of control system you could have someone stand at local display with a watch to totalize the amount then he turns off pump. Note: This person must be very good at math.
 
If you are looking for a mass measurement, kg, Coriolis flow meters not only have an integral totalizer that sums the flow over time, with either a local or remote reset, but also have some form of batch controller; like dosing control which runs two relays controlling on-off valves, one for a feed line and one for a dribble line. When the batch starts, the both valves open and the larger feed line valve stays open until ~ 97% of the preset batch value, then it closes, leaving the smaller dribble line valve open as the remaining 3% flows.

There are also separate electronic batch controllers that take the flow rate signal from the flow meter and have the buttons to easily enter batch preset values, reset, and what-not.
 
In our factory workers are uneducated, so we need very simple arrangement so we can do our BATCH process in exact weight proportional.
i.e in 1 ton reactor if we have to feed 500 kg or 500 liter of water , which type of arrangement or flow transmitter ll help us ???

pls mention link if any company is supply that type of arrangement.


Thanks all above for giving good reply.
 
How accurate do you have to be? What % error is tolerable?
Will the meter always be wetted (liquid filled) or will it run empty from time to time?

Good luck,
Latexman

Need help writing a question or understanding a reply? forum1529
 
You can't get much simpler than a mechanical meter as used for truck loading, at least for liquids and they are pretty accurate. These can start and stop pumps as well if you fit them right.

What do you use / do at the moment?

My motto: Learn something new every day

Also: There's usually a good reason why everyone does it that way
 
I have seen several arrangements where a coriolis mass flow meter and flow control valve are used for metering/dosing exact amounts of chemicals. A suitable control loop can be easily set up to use this combination for metering.
 
True mass flow meters measure mass flow rate directly using properties of mass as opposed to volumetric flow. These flow meters have found wide application because the fluid measurement is virtually independent of changing fluid parameters. The following types of mass flow meters are available:(1) Coriolis (2) Thermal
 
If it's feasible, the simplest way would be to use a scale that once satisfied turns off the pump. That way your operators will have a constant visual and would satisfy the low tech old school plant guys who want to toggle manual valves. If you go the MFC way, that is engineering-wise superior and more accurate, but then you have to have a control scheme that my be confusing to the operator if they aren't computer savvy, more so than a scale readout.

Also, the safety of your chemicals come into play. If you accidentally overfill, does everything go BOOM? Simple might not be the best in that case, you may need a parallel manual and automatic approach using new and old technologies.
 
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