With the gradual improvement of people's awareness of environmental protection and energy conservation, many large and medium-sized enterprises, such as iron and steel metallurgy, petrochemical industry, thermal power plants, etc., have taken improving combustion efficiency, reducing energy consumption, reducing pollutant emissions, and protecting the environment as the goal of improving product quality and An important way to enhance product competitiveness. Combustion devices and thermal equipment such as rolling heating furnaces in the steel industry and boilers in the power industry are major energy consumers in various industries. Therefore, how to measure and improve the combustion efficiency of the combustion device and determine the optimal combustion point is of great concern.
Determining the optimal combustion efficiency point
Not all of the fuel combustion heat supplied to heating equipment such as heating furnaces and boilers is used. Taking the steel rolling heating furnace or boiler as an example, the effective heat is the heat that must be introduced in order to heat or melt the material (and to carry out the process), and the physical heat taken away by the furnace flue gas is the main part of the heat loss. When the blast volume is too large (that is, the air-fuel ratio α is too large), although the fuel can be fully burned, the excess air in the flue gas is too large, which is manifested as high O2 content in the flue gas, and the heat loss Q1 value taken by the excess air. increases, resulting in low thermal efficiency η. At the same time, excess oxygen will react with S in the fuel and N2 in the flue gas to generate SO2, NOX and other harmful substances. For steel rolling heating furnaces, excessive oxygen content in the flue gas will also lead to thickening of the iron oxide scale of the billet and increase oxidative burning loss.
When the blast volume is low (that is, the air-fuel ratio α decreases), the content of O2 in the flue gas is low and the content of CO is high. Although the exhaust heat loss is small, the fuel is not completely burned, the heat loss Q2 increases, and the thermal efficiency η is also will decrease. In addition, the chimney will also emit black smoke and pollute the environment.
The so-called improvement of combustion efficiency means that the optimum ratio of the right amount of fuel and the right amount of air is required for combustion. Thermal efficiency is related to CO, O2, CO2 content in flue gas, flue gas temperature, heating load, atomization conditions and other factors. Therefore, the air consumption coefficient λ can be adjusted by measuring and controlling the content of CO, O2 and CO2 in the flue gas by a zirconia oxygen analyzer to achieve the highest combustion efficiency.
Combustion efficiency control has a long history. In the 1960s, CO2 analyzers were widely used to monitor the CO2 content in the flue gas to control the air consumption coefficient λ to achieve the best, but the CO2 content was greatly affected by the fuel type. After the 1970s, the O2 content in the flue gas or the combination of the O2 content and the CO content was gradually used to control the combustion efficiency.
The most direct way to improve combustion efficiency is to use flue gas analyzers (such as flue gas analyzers, combustion efficiency analyzers, zirconia oxygen content detectors) to continuously monitor flue gas components, analyze the O2 content and CO content in the flue gas, and adjust the The flow of combustion air and fuel to determine the optimum air consumption factor.
The instrument that measures the oxygen content in flue gas is called oxygen analyzer. Fuji zirconia analyzer models ZRM and ZKM are products developed to solve the above problems.
Fuji Zirconia Oxygen Analyzer
The zirconia oxygen analysis provided by Fuji Zirconia mainly includes three series of products: ordinary type, flameproof type and two-component zirconia oxygen analyzer according to different application occasions.
1) Fuji ZRM/ZKM ordinary zirconia analyzer is a relatively mature zirconia converter product, which is widely used in petroleum, chemical, metallurgy and other industries. The product has the following characteristics:
• Easy to set measuring range
The measurement range is from 0~2% to 0~50%, and can be set arbitrarily at 0.5% intervals.
• Auto-calibration/purge function
This zirconia provides standard functions such as automatic calibration and manual/automatic purge, but the solenoid valve needs to be ordered separately.
• HART communication function: (optional) RS232C (MODBUS) standard specification, RS-485 (MODBUS) (optional)
Select the product with HART communication function specification, the instrument can be set up through the communicator or modem
2) Fuji ZRM3B/ZFKG oxygen analyzer, ZRM1K flameproof zirconia analyzer, adopts the magnetic switch flameproof operation structure, saves the operation button box, and the volume is more compact.
Features
Easy to operate:
Magnetic rod operation, setting and calibration operations can be performed through the glass.
Explosion-proof certification: NEPSI explosion-proof grade: ExdII CT6 Protection grade: IP67
Multiple languages: Chinese conversational operation interface can be set, which is convenient for customers to use.
3) ZRM1L type (O2+COe) two-component zirconia analyzer
ZRM1L is a newly introduced and developed two-component zirconia converter. It can display and output oxygen content and combustible gas content at the same time in cooperation with an integrated detector, which can reflect the combustion situation more scientifically.
Features
• Explosion proof certification:
NEPSI explosion-proof grade: ExdII CT6
Dual parameter measurement and display:
One probe measures the content of O2 (oxygen) and COe (combustible gas) at the same time, 2 channels of 4-20mA output
• Easy to operate:
Magnetic rod operation, setting and calibration operations can be performed through the glass.
• HART communication function (optional):
Select the product with HART communication function specification, the instrument can be set up through the communicator or modem
Fuji zirconia oxygen analyzer has the advantages of simple structure and sampling preprocessing system, high sensitivity and resolution, wide measurement range and fast response speed.
Fuji zirconia analyzers have a wide range of applications, such as:
Circulating fluidized bed boilers in thermal power plants are used for flue gas monitoring in combustion control rooms;
Steel rolling heating furnaces in iron and steel plants are used to detect furnace gas atmosphere when reducing oxidation burning loss or decarburization layer thickness;
The full hydrogen heat treatment furnace is used to detect whether the radiant tube is burned through and leaked;
Design and research on the structure size of the burner when developing new burners (regenerative, low NOX, radiant tube);
Vehicle exhaust emission testing;
Flue gas monitoring of other industrial kilns and waste incinerators.
Regarding more details about fuji Analyzer,pls feel free to contact us sales6@xatzd.com
