Featured Slurry Flow Meters

Industrial Slurry Flow

The measurement of industrial Slurry and sewage has been one of the difficult problems to be overcome by the measurement workers for many years. There are two main reasons for this.

One is the fluid characteristics: the medium is dirty, the solid-liquid dual phase, the composition is complex, and it is easy to adhere and deposit.

The second is the measurement characteristics: the field working conditions are harsh, the detection devices are easily damaged and difficult to maintain, and the reliability of the measurement instruments is high.

In recent years, with the continuous deepening of the low-cost strategy of Jinan Iron and Steel, the implementation of measures such as solid waste recycling and zero discharge of sewage. In the process, the iron-making dedusting water, the steel-making dedusting water, and the phosphorus-removing water (collectively referred to as industrial sludge water) are recycled to the sedimentation tank for filtration. The pump is pressurized and transported to the sintering plant for mixing and reuse. The accurate measurement of this industrial sludge water is directly related to the quality of the sinter.

For this reason, how to accurately measure industrial Slurry sewage has always been our topic of discussion.

Extended Reading: Differential Pressure (DP) Flow Meters Technology

What is the Best Flow Meter for Slurry？

Which sludge flowmeter is better to choose?
From the current measurement technology, it is more common to choose an electromagnetic flowmeter to measure sludge.
Sino-Inst considers electromagnetic flowmeter as Best Flow Meter for Slurry.

The properties of the sludge to be treated and the deep dewatering process of the sludge, the electromagnetic flowmeter has the following technical characteristics:

1. It can measure the flow of almost all conductive liquids, silts, viscous materials and mud.
2. A prerequisite for the measurement is that the medium must have a minimum conductivity.
3. Temperature, pressure, density and viscosity do not affect the measurement results.

When measuring sludge, the type of electromagnetic flowmeter selected is the use of HC electrode, PTFE lining, one-piece type, 20% of the sludge is added with medicine and stirred into a sludge slurry (solid content is about 10%~15%) through pumping. on the pipeline.

In conclusion

1. The electromagnetic flowmeter can be used for sludge with a solid content less than or equal to 15%, and the purpose of accurate and stable measurement in the slurry is achieved.
2. The use of grounding flanges and a good grounding connection are necessary conditions to ensure the stable and reliable operation of the flowmeter.

Magnetic Inductive Flow Meter

Magnetic Inductive Flow Meter is a flow meter that measures the flow of conductive fluids. Abbreviated as EMF, also called Electromagnetic flowmeters. It is a kind of Volumetric flow meter. A magnetic flow meter measures the velocity of conductive liquids moving through a pipe or conduit. In the wastewater treatment industry, Magnetic Flow Meter is the best flow meter choice.

Magnetic flow meter working principle

Magnetic flow meters use the principle of Faraday’s Law of Electromagnetic Induction to measure the flow rate of liquid in a pipe. In the magnetic flowmeter pipe parts, a magnetic field is generated, and channeled into the liquid flowing through the pipe. 

Faraday’s Law states that the voltage generated is proportional to the movement of the flowing liquid. A conductor moving through a magnetic field produces an electric signal within the conductor. And the singal is proportional to the velocity of the water moving through the field. 

As fluid flows through the magnetic field, conductive particles in the fluid create changes. This variation is used to measure and calculate the velocity of water flow through the pipe. When the fluid moves faster, more voltage is generated. The electronic transmitter processes the voltage signal to determine liquid flow.

Magnetic flow meter principle – Faraday’s Formula

Faraday’s Formula
E is proportional to V x B x D where:

E = The voltage generated in a conductor
V = The velocity of the conductor
B = The magnetic field strength
D = The length of the conductor

To apply this principle to flow measurement with a magnetic flow meter. First is to state that the fluid being measured must be electrically conductive for the Faraday principle to apply.

As applied to the design of magnetic flow meters, Faraday’s Law indicates that:the signal voltage (E) is dependent on V, B, D.V is the average liquid velocity ;

B is the magnetic field strength ;

D is the length of the conductor ( which in this instance is the distance between the electrodes).

Extended reading: Flow meter totalizer calculation

Electromagnetic flowmeter to measure Slurry flow

Which sludge flowmeter is better to choose? In general, it is more common to choose an electromagnetic flowmeter to measure sludge.

1. The electromagnetic flowmeter has no mechanical inertia and has a flexible response. It can measure the instantaneous pulsating flow, and can also measure the flow in both positive and negative directions.
2. The output of the electromagnetic flowmeter is only proportional to the average flow rate of the measured medium. It is independent of the active state (laminar or turbulent) under a symmetric distribution. Therefore, the range of electromagnetic flowmeters is extremely wide. Its measurement scale can reach 100:1. Some even reach the operational flow scale of 1000:1.
3. The sensor structure of the electromagnetic flowmeter is simple. There are no moving parts inside the measuring tube, nor any saving parts that impede fluid movement. So no additional pressure loss occurs when the fluid passes through the flowmeter. It is one of the flow meters with the lowest operating energy consumption in the flow meter.
4. The caliber of industrial electromagnetic flowmeters is extremely wide. From a few millimeters to several meters, and there are real-flow calibration equipment with a diameter of 3m in China. It lays the foundation for the application and development of electromagnetic flowmeter.
5. Electromagnetic flowmeter is a volume flow measurement surface. In the measurement process, it is not affected by the temperature, viscosity, density and conductivity (in a certain scale) of the measured medium. Therefore, the electromagnetic flowmeter only needs to be calibrated by water. It can be used to measure the flow of other conductive liquids.
6. It can measure the flow rate of dirty medium, corrosive medium and suspended liquid-solid two-phase flow.

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Related Products

Sino-Instrument offers over 50 Slurry Flow Meter for flow measurement.

About 50% of these are differential pressure flow meters,

40% is the magneitc liquid flow sensor, and 20% are Ultrasonic Transmitter and mass flow meter.

A wide variety of Slurry flow meters options are available to you,such as free samples, paid samples.

Sino-Instrument is a globally recognized supplier and manufacturer of Slurry Flow Meter instrumentation, located in China.

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Steam Flow Meters for Sale

Inaccurate steam flow measurement is a common Requirement in the heating industry. The main reasons are as follows:

superheated steam

Steam is a relatively special medium. Generally speaking, steam refers to superheated steam. Superheated steam is a common power source. It is often used to drive steam turbines to rotate. And then drive the generator or centrifugal compressor to work.

Superheated steam is obtained by heating saturated steam. There is absolutely no droplet or liquid mist in it, and it is an actual gas.

The temperature and pressure parameters of superheated steam are two independent parameters. Its density should be determined by these two parameters.

After the superheated steam is transported over a long distance, it changes with the working conditions (such as temperature and pressure). Especially when the degree of superheat is not high, it will enter the saturated or supersaturated state from the superheated state due to the decrease of the heat loss temperature.

Converted to saturated steam or supersaturated steam with water droplets. The saturated steam is suddenly decompressed greatly. When a liquid expands adiabatically, it also turns into superheated steam. In this way, a vapor-liquid two-phase flow medium is formed.

Read more about: Condensate Flow Meter-Steam Condensate Flow Meter|Types & Selection Guide

Saturated Vapor

Steam that has not been heat treated is called saturated steam. It is colorless and odorless. Non-flammable and non-corrosive gases. Saturated steam has the following characteristics:

(1) There is a one-to-one correspondence between the temperature and pressure of saturated steam. There is only one independent variable between the two.

(2) Saturated steam is easy to condense. If there is heat loss during transmission. Droplets or mist form in the steam. and lead to a decrease in temperature and pressure. Steam containing liquid droplets or mist is called wet steam.

Strictly speaking, saturated steam contains more or less a two-phase fluid of liquid droplets or mist. Therefore, different states cannot be described by the same gas state equation.

The content of liquid droplets or mist in saturated steam reflects the quality of the steam. It is generally expressed by the parameter of dryness. The dryness of steam refers to the percentage of dry steam per unit volume of saturated steam. Indicated by “x”.

(3) It is difficult to accurately measure the flow rate of saturated steam. Because the dryness of saturated steam is difficult to guarantee. General flowmeters cannot accurately detect the flow rate of two-phase fluid. Fluctuations in steam pressure will cause changes in steam density. Additional errors will occur in the indication value of the flowmeter. .So in steam measurement, it is necessary to try to maintain the dryness of the steam at the measurement point to meet the requirements. If necessary, compensation measures should be taken to achieve accurate measurement.

Extended reading: What Is Difference Between Rotameter And Flow Meter?

Analysis of Steam Measurements

Flow meters are currently used to measure steam flow. The measurement medium refers to single-phase superheated steam or saturated steam.

For steam with frequently changing phase flow, there will definitely be inaccurate measurements.

The solution to this problem is to keep the steam superheated and minimize the water content of the steam.

For example, strengthen the insulation measures of steam pipelines and reduce the pressure loss of steam. to improve the measurement accuracy.

However, these methods cannot completely solve the problem of inaccurate steam flow measurement. The fundamental solution to this problem is to develop a flow meter that can measure two-phase flowing media.

There are many types of flow meters used to detect gas flow. The most common applications are velocity and volumetric flow meters. Their common feature is that they can only measure the volume flow under operating conditions continuously. The volume flow is again a function of the state.
The volume flow in the working state cannot exactly represent the actual flow.
In engineering, it is generally expressed as standard state volume flow or mass flow.
The so-called standard state volume is the volume of gas at 0°C and 1 standard atmosphere or the volume at 20°C and 1 standard atmosphere.

The case where mass flow is the unit of measurement. At present, when the scale gas flow meter is not used in many applications. The normal temperature and pressure of the selected gas are the design conditions. Convert the volume flow under the design state to standard volume flow or mass flow. Its conversion coefficient contains the factor of gas density. When the working state of the gas medium deviates from the design state, the flow indication value will have errors.

Furthermore the composition, content or temperature of the gaseous medium changes. It also affects flow measurement. Therefore, the measurement of steam flow needs to take compensation measures. In addition, the compensation factors due to the state change of the steam are also complicated.

The density of superheated steam is determined by the temperature and pressure of the steam.

And in different ranges of parameters, the expression of density is also different. cannot be represented by the same general formula. Therefore, a unified density calculation formula cannot be obtained.

The temperature and pressure compensation formulas can only be derived individually.
In the case of large temperature and pressure fluctuation range. Except for temperature and pressure compensation. Compensation for the gas expansion coefficient Σ also needs to be considered.

No matter what kind of flow meter is used to detect the flow of saturated steam. When working under conditions of steam pressure fluctuations, pressure compensation measures must be taken. This is because the steam density factor is included in the flow equation. When the operating conditions are inconsistent with the design conditions, the readings will have errors. The size of the error and the working pressure are related to the size of the design pressure deviation. A negative error will occur if P real > P set. Otherwise there will be a positive error.

The dryness condition of steam is an important condition related to whether the steam flow can be accurately measured. At present, the online steam dryness testing instrument is being developed. The application of the dryness meter to the steam flow measurement and compensation system will further improve the measurement accuracy. The following three measures should be taken at present:

1. The pipeline for conveying steam must have good insulation measures to prevent heat loss.
2. Drain the steam pipeline section by section, and set steam traps at the lowest part of the pipeline and the pipeline in front of the instrument to drain the condensed water in time.
3. During the operation of the boiler, the phenomenon that the liquid level of the steam drum is too high should be avoided, and the large fluctuation of the load should be minimized.

Selection of Steam Flow Meters

There are 5 main factors to consider when choosing a flow meter for steam metering:
Characteristics of the fluid being measured, production process conditions, installation conditions, maintenance requirements, and characteristics of the flow meter.

Here, we focus on discussing the characteristics, installation conditions, maintenance requirements and several issues that should be paid attention to when choosing a flow meter.

At present, the instruments for measuring steam flow mainly include vortex flowmeter, differential pressure type (orifice plate, uniform velocity tube, elbow) flowmeter, split rotor flowmeter, Annubar flowmeter, float flowmeter, etc.

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The choice of Measuring Steam Flow and steam flow meter is very important. Accurately measuring steam flow is a need and a common concern in the production sector. With the development of the economy, the voice of improving the measurement level is getting louder and louder.

We should choose the appropriate flowmeter according to the actual measurement conditions.

The choice of Measuring Steam Flow and Steam Flow Meters has always been an industry challenge.

Sino-Inst, Manufacuturer for Steam Flow Measurement Flowmeters.

Sino-Inst’s Steam Flow Measurement Flowmeters, made in China, Having good Quality, With better price. Our Steam Flow Measurement instruments are widely used in China, India, Pakistan, US, and other countries.

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