Oxygen Gas analyzer


Oxygen Gas Analyser




 

What is a Gas Analyzer?


Definition of a gas analyzer

A gas analyzer measures or traces the concentration of a specific gas in a sample gas.

In industry, gas analyzers are used to measure the concentration of oxygen, CO, NOx, SO2, or any other gas for the smooth operation of the process, fuel-saving, and environmental protection.

Oxygen gas analyzers

There are four types of oxygen measuring methods used in the industry. 

1. Zirconia type oxygen analyzer

 Zirconia is a solid electrolyte that exhibits a conductivity of oxygen ions at a high Temperature of 800 centigrade.

Working principle of zirconia gas analyzer

 In the zirconia gas analyzer porous Platinum electrodes are attached on both sides of the Zirconia element to be heated up and sample gases of different types having a partial oxygen concentration are brought into contact with respective surfaces of the Zirconia, so the device act as oxygen concentration cell. As shown in the figure below zirconia cell working is explained.



Ionization of oxygen gas in the sample causes an emf to be generated between both electrodes and voltage is induced on the electrodes,  the induced voltage is directly proportional to the oxygen concentration in the sample has of the gas analyzer. 

Zirconia analyzer Advantage

Zirconia oxygen analyzer Can be directly installed in a combustion process no sampling is required.

Zirconia analyzer Disadvantage

If a flammable gas is present in the sample a measurement error occurs in the zirconia analyzer, so it is not recommended to measure flammable gas. 

2. Paramagnetic type oxygen           analyzer

The paramagnetic oxygen measurement method uses the paramagnetic property of the oxygen. When oxygen is passed through a magnetic field, the oxygen ions are attracted by the magnetic field so the advantage is taken by this paramagnetic quality of the oxygen.

 A dumbble is used to deflect the light emitted by a light source and the deflection in light is detected by a light detector, the deflection of light is directly proportional to the concentration of oxygen gas in the sample. 

This analyzer is a dumbbell-type paramagnetic oxygen analyzer. Because this analyzer is based on that the magnetic susceptibility of oxygen gas is larger than coexisting gases, stable measurement is ensured which is unaffected by coexisting gases in the sample. 

A paramagnetic oxygen analyzer is suited for measuring the oxygen concentration in the inflammable gas. The principle of measurement of oxygen in the sample gas is dependent on the strong magnetic property of oxygen molecules. Therefore, measurement is almost unaffected by other molecules weaker in magnetic property than oxygen.

 Advantages of Paramagnetic gas analyzer 

 1. Paramagnetic type oxygen analyzer is Suitable for measuring oxygen concentration in the inflammable gas sample.

 2. Paramagnetic oxygen analyzer is Smallin size so it is manageable to handle.

 3. we can use a paramagnetic oxygen analyzer with a wide range of power supplies.

 4. The output of the paramagnetic type oxygen analyzer is linear.

 Working principle of paramagnetic oxygen analyzer

In a paramagnetic oxygen analyzer, two glass spheres filled with nitrogen gas are suspended with the support of a strong metal wire. At first, the spheres are kept in balance in an inhomogeneous magnetic field. 




When oxygen molecules having a large magnetic susceptibility flow in this magnetic field, the molecules are pulled toward the stronger magnetic field zone and the spheres are moved away from the zone. The resulting deviation of the spheres is detected with the light source, reflecting mirror, and the light-receiving element and a current is flowed through the feedback loop to control the imbalance, due to this current, spheres can return to the initial balanced state. The current flowing through the feedback loop is proportional to the oxygen concentration in the sample gas. Thus, the oxygen concentration is converted into an electric signal. 

3. Optical type oxygen analyzer

An optical type gas analyzer is also called TDL (Tunable Diode Laser). It is used to measure the concentration of gas. The quantity of lasers absorbed by the gas is directly proportional to the concentration of gas in the sample. So the more absorption of the laser means a high concentration of gas in a sample gas.




4. Electrochemical type oxygen analyzer

In this type of oxygen analyzer Oxygen is dissolved in an electrolytic solution. Two electrodes (anode and cathode) are used to measure the current passing through the electrolyte, this current is directly proportional to the concentration of oxygen in the solution. This is a very simple chemical method for oxygen analysis.





Top 50 instrumentation interview questions


Radar level transmitter


Ultrasonic Level Transmitter


Capacitive level sensor


Calibration of flow meter


Thermocouple


Infrared gas analyzer


level measurement


Pressure measurement 


Vibration measurement


Solenoid Operated Valve


Flow measurement


Gas analyzer


Belt Weigh feeder


Temperature measurement


Load cell





Comments

Post a Comment

Popular posts from this blog

Top 50 Instrumentation Interview Questions

 Instrumentation Interview Questions and Answers Instrumentation Interview Questions and Answers There are different questions that you can be asked in an interview for the post of instrument technician, instrumentation engineer, or instrument supervisor. Most interview questions are related to the industry you are going to apply to, and they prefer a skilled person and have a good knowledge of instruments used in that specific industry. Here I will try to write the question with answers that are mostly asked for instrumentation professionals. Q. No. 1:  What is instrumentation? Ans :  Instrumentation is a branch of science which deals with the measurement and control of process variables in a process. Q. No. 2  What is the process? Ans :  The process is defined as the adoption of series of steps or methods to acquire a predefined result. Q. No. 3  What is a process variable? Ans :  It is a variable in the process that we are attempting to maintain...
Read more

Control Valve Basics

Image
Control Valve  What is a control valve A control valve is an instrument that regulates the flow of fluids (oil, water, or gases) as the valve position is changed by moving the stem with help of an actuator. This actuator may be a motor of a pneumatic or hydraulic jack.  The control valve is the most commonly used final control equipment in the control loop of an industrial process. The control valve receives a control signal as input from plc or DCS, a controller is used to compare the setpoint and control valve actual position and then decides to open or close the valve according to match the set point. Classes of  Control Valve on the base of motion Two main types of valves are according to the motion of the stem. 1. Linear motion  2. Rotary motion 1. Linear motion  Linear motion is a movement of valve stem up and down, a common type of linear motion control valve is the Gate valve. 2. Rotary motion  A rotary motion valve moves or rotates at an angle usu...
Read more

Radar level measurement

Image
 Radar Level  Radar level transmitter are used to measure level in industrial applications. Radar level measurement method is an advanced method. In radar level transmitter time of flight method is used to measure the level. By calculating this time of flight we measure the level of liquid or solids.  RADAR level have a transmitter which transmit microwave or radar waves after colliding with material they return back to the receiver.  The time from the transmitter to the echo return to the receiver, is calculated, which is proportional to the level. This time is calculated by the formula:  Distance = (Speed of light x time delay) / 2 This calculation is done by a built in microprocessor and the level is displayed on screen or lcd, a signal proportional to level in 4 to 20 mA is output of level transmitter , this standard current signal of 4 to 20 mA is for plc or dcs. Time of Flight technology  Time of flight technology is used in  devices that are mu...
Read more