mass flow meter for slurry

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Thread Starter

dave balabuck

looking for a coriolis mas flow meter for a slurry application.

line size could be a problem need 12 to 18 inches
any sugestions other than flow and density
 
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Mihir Ramkrishna

In our HDPE plant we are using PROMASS 63 ENDRESS & HAUSER make mass flow meters. We do not have such a big line. You can please confirm with M/s E&H. One thing I can tell u is they are great meters and with very little installation limitations. We have been using them since 4 years and have no problems. By the way they are straight run twin tube meters with least chances of choking as they can be mounted vertically and horizontally to suit your requirements..
 
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david mertens

The biggest coreolis mass flow meters I've ever seen was a micromotion (now fisher rosemount). The pipe must have been at least DN100 (+/- 40 inches?) but these are extremely expensive custom made. Would a push plate be an option? This is a fairly low cost instrument based on the fact that a plate on which the liquid is falling is pushed against a force measurement. The force is proportional to the weight of the liquid (and the height from which it falls and the diameter of the plate). This of course is only possible in free fall of the liquid, because otherwise you would only be measuring the force of your pump.
 
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Craig McIntyre

Compact six inch coriolis mass flow meters with density measurement are now on the market. These can be combined in parallel to address larger flow cross-sections. If you have abrasion issues you may want to go the traditional way with a slurry magmeter and a gamma density system.
Endress+Hauser is a solution source for these approaches.

Craig McIntyre
 
Coriolis that size?... probably not and slurry? wear?... may not be a good idea. What's the problem with the conventional magnetic flowmeter/nuclear density gauge combination in this particular case?

Vince Dooley
 
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Coriolis manufacturers has meter up to 6 and 9 inch diameter. You could use two meter in parallel but the main problem in this application is the abrasion. What is the slurry composition and concentration?

Here the mining company only use magnetic flowmeter + nuclear density meter.

Regards

Jorge Diaz Z
Stgo-Chile.
 
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Dharmesh Shah

Try either Micromotion or Rheonics make of mass flow meters. Even Rheonik supports far higher sizes of mass flow meters as compared to Micromotion. Just see which model gets fit into your process requirements.

Dharmesh
 
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Kenny Hartman

David, there are no vendors that provide or could provide a 12" coriolis meter. The drivers to produce the coriolis effect would require a small power plant.

A combination of ultrasonic doppler meter and smaller coriolis meter. The ultrasonic your need to be carefully with. Ask your local vendor to test it first before sending him a PO. Ultrasonic will give you a flowrate. Adding a small bypass line will give you a density measurement. With a little calculation by your PLC, 12" massmeter. The best accuracy you should is 2%.
 
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Ian Verhappen

Mass meters are OFTEN not based on the line size and in the case of an abrasive slurry I STRONGLY recommend consideration be given to using one of
the newer 'straight tube' style devices. Similarly, if you need more than one meter be sure to use a Y rather than T splitter and keep both sides hydraulically equal.

Ian
Ian Verhappen
Syncrude Canada Ltd.
PO Bag 4009, MD 0032
Fort McMurray, Alberta T9H 3L1
P 780 790-4079, Cell 799-6017
F 780 790-5190
[email protected]
 
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david mertens

You are right, DN100 corresponds to 4" not 40", my mistake, even the 4" is an incredibly big and heavy instrument.
 
Why not a flow meter and density transducer solution? have you had a bad experience?
I suspect nothing like the financial shock you will get trying for a mass flow meter in this size of pipe and the advise you have already
been given about using a straight tube design is good but probably impractical since most need even higher flow velocities than the conventional twin bent tube designs to develop the necessary phase angles and high velocities mean errosion; Not to mention the problem of
finding a unit that will handle your flows. In all probabilty you will be offered meters sized at much smaller pipe sizes than your pipe and
this will undoubtedly cause some problems for you.
Frankly with the performance you can get from a mag meter these days you can get a line size unit offering minimal obstruction, plastic or
ceramic lined and capable of exceptional flow rate turndown and at a virtually giveaway price.
Now I can't think that you have a problem with Magnetic flow so i guess it is the density measurement that is a problem. What have you used
before?
The calculation of mass flow couldn't be simpler these days. For density measurement you have an ever increasing choice of devices.
Radiation (gamma ray) devices have been mentioned and can be effective. I can only advise you on This means vibrating digital density meters. If you are prepared to consider Coriolis meters then i don't see that you have a problem with vibrating digital density
transmitters, especially as modern insertion devices have a very wide application history on all sorts of mineral slurries from china clays,
underflow from granite washing plants, foundary casting slurries, phosphur slurries for CRT coating, chalk slurries from quarry to cement
kiln (including viscosity measuring versions) or sand slurry measurement in wash tanks.
Insertion types mean you don't have any maintenance problems that you might get with a slip stream type.
The insertion types have the advantage that so long as the flow velocity is sufficient to prevent solids drop out, they quite like a
relatively low flow velocity regime which means errosion is raely a problem. I've seen units used for chalk slurries that quite evidently
suffered years of excess flow before finally losing calibration due to the impact of something heavy enough and fast enough to bend the short length of 3/4" bar stock which supported the sensor and even then it still worked, it could have been re-calibrated. (I can supply you a picture of this unit if you like)
Our own company has hundreds of tube and fork vibrating units installed in these applications and an installed base which includes several
hundred with one company alone.
I would suggest you need to visit as many density meter manufacturers sites as you can and talk to them. Certainly, investigate mass flow
but be prepared for the cost penalty.
But then i suggest re-visiting the mag flow and density meter option. When you do that be sure to shop around and see what everyone has to
offer. Many companies can provide references to happy users.
 
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koen_verschueren

Krohne has a mass flow meter with a straight tube which is ideal for slurry. "http://www.krohne.de":http://www.krohne.de (type CORIMASS G+)
They can only supply diameters up to DN100 (4").
If you only need the density of the slurry you can place the mass flow meter in a bypass line. Make sure to reduce the main pipe so you keep enough flow through the bypass.
If you also need the flow you have to combine this mass flow meter with a conventional flow meter. (AQUAFLUX from Krohne (Up to 120")) With the flow from the flowmeter and the density from the mass flow meter you can calculate the mass flow.
 
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There are some very serious problems with this approach.

First, while the Corimass meter, or any other Coriolis mass flow meter will measure the slurry mass flow, and extract a computed value for slurry
gravity, it _is_ subject to wear dependent on the abrasive qualities of the slurry. Replacing Coriolis flow tubes is not an inexpensive investment.

Second, the idea that a small sample from a bypass is likely to be representative of the density in a larger slurry line bears thinking about. For this to be true, it would require fully turbulent flow at any flow rate. Since that is unlikely, it is equally unlikely to provide a representative sample of density at all flow rates.

Third, slurries tend to "dewater," that is, their density is greatest at the pipe wall and least at the centerline, unless the flow is extremely
turbulent. So if you are not taking, by means of some sort of perforated sample tube inserted to at least the midline, a sample across the density
gradient, you are likely to be measuring a significantly higher density than the average density in the slurry. Trying to produce such a sample tap is non-trivial, and if the slurry exhibits coating characteristics, the tap will simply plug up regularly.

I'm not saying it WON'T work, I'm saying you have to think about it, because it comes with significant downside potential.

This is why slurries are typically measured with a magnetic flowmeter and a nuclear densitometer.

Walt Boyes

---------SPITZER AND BOYES, LLC-------------
"Consulting from the engineer
to the distribution channel"

[email protected]
21118 SE 278th Place
Maple Valley, WA 98038
253-709-5046 cell 425-432-8262 home office
fax:801-749-7142
--------------------------------------------
 
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Adrian Farinas

Special attention must be paid to the ultrasonic meter in this particular application. Solids in the slurry may reflect the ultrasonic wave giving an erroneous flow reading...
 
You can try with Bopp and Reuther for such big size. We have recently installed a 10" mass flow meter Model UM93
 
There are two types of ultrasonic meters

1. Doppler - info here "www.flowmeterdirectory.com/flowmter_artc/flowmeter_artc_02051301.html":http://www.flowmeterdirectory.com/flowmter_artc/flowmeter_artc_02051301.html .
2. Transit time- info here "www.flowmeterdirectory.com/flowmter_artc/flowmeter_artc_02012201.html":http://www.flowmeterdirectory.com/flowmter_artc/flowmeter_artc_02012201.html .

Some manufacturers like Controlotron and Eesiflo make meters that measure in both modes without changing sensors

I would recommend you buy a meter that can measure in both modes so you don't waste your money

Renting one before buying is also better so you know what you will be in for.
 
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