I. Overview

The integrated zirconia oxygen analyzer is widely used in electric power, metallurgy, heating, building materials, electronics and other departments because of its simple structure, convenient maintenance, fast response speed, and wide measurement range to analyze various industrial boilers and kilns. The oxygen content of the flue gas in the furnace can improve the combustion efficiency, save energy and reduce environmental pollution.

The integrated zirconia oxygen analyzer consists of a converter and a detector (commonly known as an oxygen probe). On the zirconia concentration cell, the core component of the detector, nanomaterials and advanced production technology are used, and the electrode coating is added Additives that inhibit electrode aging. Greatly improve the accuracy and service life of the zirconia measuring probe. The detector adopts an in-line probe structure and does not require a sampling system, which can reflect the combustion condition in the boiler in time. If used in conjunction with an automatic control device, it can effectively control the combustion condition. The converter adopts the intelligent design of single-chip microcomputer, and the liquid crystal display of Chinese characters makes the data display and function control more humanized; it can be connected with various types of DCS data access equipment. The operation of the instrument becomes simple and easy to master. Has the following characteristics:

1. It has strong versatility and can directly replace oxygen analyzers from other manufacturers.

2. Red LED digital tube digital display.

3. Free setting within 0-25% of the oxygen range (the lowest range is 0-5%).

4. The temperature is controlled by PID, and the constant temperature points are 700°C and 750°C (can be selected on site).

5. It can set the upper and lower limit alarm indication of oxygen quantity, and the upper and lower limit alarm indication of temperature.

6. The background potential is automatically corrected.

7. Can be calibrated online with standard gas.

8. The 4-20mA standard current output is optically isolated from the main circuit, and can be directly transmitted into the DCS system.

9. Various fault information prompts.

2. Working principle

Integrated Zirconia Oxygen Analyzer Zirconia is a high-temperature electrolyte concentration battery, which has the conductivity that can generate oxygen ion migration in a high temperature environment of hundreds of degrees. The oxygen partial pressure of the platinum electrode on both sides of the zirconia is different than that of the gas (air or other gas), and a certain amount of oxygen ions migrate between the two electrodes to generate an oxygen concentration potential. The relationship between the potential value and the oxygen concentration can be calculated by using Nernst formula to express:

E=RT/4F×LnP1/P2

In the formula: E - oxygen concentration difference potential (V)

R—ideal gas constant (8.314J/moLK)

T—temperature value (K)

F—Faraday constant (96500c/moL)

P1—reference gas partial pressure (air)

P2—Partial pressure of the gas to be measured

The transmitter converts the measured data through the single-chip computer, displays the oxygen content on the digital tube, and converts it into a current signal for use by a computer or recorder. The relationship between oxygen concentration and oxygen concentration difference potential at 700 °C and 750 °C is shown in the attached table.

3. Technical indicators

Range: 0.01～25.0%O2 (range can be freely set from 5.00%-25.00%)

Output signal: 4 ~ 20mA load resistance ≤ 500Ω isolation

Repeatability: ±0.5% of full scale

Basic error: ≤±2% (full scale)

Stability: ≤±1% (instrument continuous verification for 4h)

Response time: 90% response within 5 seconds when standard gas is introduced from the detector inlet

Ambient temperature: Detector -10℃～80℃ Converter 0℃～40℃

Power supply and power consumption: power supply 220±10%VAC, maximum power consumption is 150W

Sample gas temperature: ≤ 700 ℃ (above 700 ℃ negotiated supply)

Sample gas pressure range: ±10KPa

Detector length: 0.4m; 0.8m; 1.0m; 1.2m; (other lengths can be produced according to user requirements)