Coriolis flowmeter

Coriolis flowmeter 267 Costich, E. W. 280,283,288.311 Coulson, J. M, 517, 565 Counter- and co-current flow, mass transfer 621 Countercurr ent contacting of phases 600 --flow 387... 

Mass Meters Mass flowmeters measure the rate of mass flow through a conduit. Examples include Coriolis flowmeters and thermal mass flowmeters. Coriolis flowmeters can measure fluid density simultaneously with mass flow rate. This permits calculation of volumetric flow rate as well. Section 8 includes brief descriptions of Coriolis and thermal mass flowmeters. 

Coriolis Mass Flowmeter This type, described in Sec. 8, offers simultaneous direct measurement of both mass flow rate and fluid density. The Coriolis flowmeter is insensitive to upstream and downstream flow disturbances, but its performance is adversely affected by the presence of even a few percent of a gas when measuring a liquid flow. 

Coriolis flowmeters can be used in both gas and liquid services, but are not suited for the measurement of their mixtures. The flow detection capability can range from 0 to 30,000 kg/min (0 to 65,000 lb/min), and these meters are available in sizes from 1 to 250 mm (0.05-10 in.). Their measurement error is 0.1% AF +/- zero offset which is about 0.01% within a 10 1 range. This error rises to 1% FS within a 100 1 range. This flowmeter can operate at temperatures from cryogenic to 450°C (850°F), and at pressures from atmospheric to 345 bar (5,000 psig). 

The measuring uncertainty for a 1 in. (DN25) Coriolis flowmeter. The maximum flow speed is 80 in./s (2 m/s), which is 20% of the maximum specified flow speed of the flowmeter. The curves show the specified error limits. 

Figure 5 gives the flow scheme of a feed oil system. A high pressure plunger pump feeds the reactor with oil at a pressure of about 75 bar. The mass-flow of feed oil is measured by three Coriolis-Flowmeters. The second pump is out of line. The feed oil flow is adjusted by pump speed which is variable in a range of 25 to 110 rpm. Two resonators are used for pulsation damping. 

The allowable pulsation in the plant depends for one thing on possible excitation of the mechanical structure and on the other on the installed Coriolis-Flowmeters (CFMs). 

Figure 3 shows the test section and instrumentation. Ten wall temperatures on the tube external surface were measured with 0.5 mm diameter calibrated type E thermocouples electrically insulated from the aluminium. Fluid inlet and outlet temperatures were measured with 1 mm diameter calibrated type K thermocouples. Cah-bration was carried out with a Rosemount 162-CE platinum thermometer. Due to the high thermal conduchvity of the aluminium and the low thickness of the tube walls the measured temperature is very close to the wall temperature in contact with the fluid (the difference less than 0.01 K). The inlet fluid pressure was measured with a calibrated Rosemount type 11 absolute pressure sensor. Two calibrated differential pressure sensors measured the pressure loss through the test section. A Rosemount Micro-motion coriolis flowmeter was used to... 

Hoglen, W. and Valentine, J. Coriolis flowmeters improve hydrogen production Accurate steam-to-carbon ratio control provided efficient operation. Hydrocarbon Processing, 2007, 86 (8), 71. 

To measure mass flow we must determine slurry density and volumetric flow rate. A Coriolis flowmeter may be considered a true mass flowmeter because it... 

In today s industrial applications, Coriolis mass flowmeters are widely used by process engineers to monitor mass flow rate. This meter measures the Coriolis force that depends on the mass momentum of the flow, and, in principle, it can be applied to both single- and mixed-phase flows. Magnetic or optical detectors are generally used to detect mass-flow-related Coriolis acceleration. A brief description of the Coriolis flowmeter will be presented because it is widely used in industrial processes. 

During an experiment the mass flow rate is controlled by means of the Coriolis flowmeter, and the pressure drop in the loop is measured by a differential pressure cell. Make-up gas is added to the loop in order to keep the static pressure constant when the hydrates form. Measurement of the make-up gas flow rate is a way to observe the hydrate growth kinetics and amount formed. Knowing the amount of gas necessary to saturate the oil phase at 75 bar, when the temperature is decreased from 20°C to 4°C, and assuming that crystals of hydrates form in stoichiometric conditions, it is possible to evaluate the rate of conversion and the mass of water consumed. 

The test rig includes a 22 m long loop of 1 inch diameter and a 90-liter tank used to store adequate amounts of liquid hydrocarbon, deionized water, and gas. The liquid phase is circulated through the loop by means of a Moineau pump. The loop is fiuther equipped with a sapphire window located at the inlet of the pipe, a Coriolis flowmeter and a thermostatic device to adjust the temperature of the loop. A... 

The Micro-Motion 1700/2700 Coriolis flowmeter (Figure 9-12) received its lEC 61508 assessment in 2005. The basic technology is frequency based providing high inherent safety as most internal failures wiU result in lack of frequency and are therefore detectable by the transmitter. 

Measuring methods which deduce the flow directly from flow characteristics are very common. There are versatile methods being used, which all depend on the velocity of the flowing medium. The most important are measurements with orifice devices, with suspended bodies, and according to a magnetic-inductive method. Beyond that there are flowmeters which use the pressure drop of a flowing liquid in a capillary, and magnetic-inductive, ultrasonic, and Coriolis flowmeters. 

When a fluid moves in a tube that is rotated, it experiences a Coriolis force proportional to its mass and velocity and to the angular velocity of the tube. In the Coriolis flowmeter, the tube is not rotated but vibrated. Vibrations in the tube are set up and a small elastic deformation in the tube results from the Coriolis force. 

Finally, there is an opportunity to calculate pH online for tlie flat part of a titration curve if there are coriolis flowmeters to accurately measure the mass flow and density of two component mixtures or streams with sufficiently constant acid and base concentrations. An inferential measurement or pH estimator based on an online titration or charge balance model can become a third measurement that enables middle selection. In one application, it was found that the calculation was more accurate than the electrode readings because of the flatness of the titration curve. A single coriolis flowmeter on each of the influent and reagent... 

Coriolis flowmeters can be used to replace pH electrodes and provide online displays of reagent usage, process efficiency, and WM titration curves. 

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