requestId:68629af9d731d4.13191961.
Abstract: This article mainly introduces the principles and application of the control targets of the mechanical furnace exhaust slag burning furnace ACC automatic combustion control technology, and conducts detailed calculations on the control methods and system parameters of the hollow gas and residue feed quantity of the automatic combustion control system. It provides the main reference for the development and application of the ACC automatic combustion control technology that is equipped with large mechanical furnace exhaust slag burning furnace.
Key achievements that can be achieved.可: boiler; dregs burning furnace; automatic burning control
1. Introduction to automatic burning control system of dregs burning power plant
(Auto Combustion Control, briefly ACC)
It has been mentioned later that “steam evaporation” is one of the main targets of the furnace. That is to say, although the heat value and incineration volume change at all times, the intersection of the furnace rate and the adjustment of the combustion air volume can be achieved by controlling the furnace bed rate to achieve a stable steam production capacity.
In the combustion theory, the amount of air required during combustion can be considered as a function of the heat generated by combustion. In the burning furnace field where the residual heat boiler is installed, the combustion heat can be changed to the steam evaporation amount (Qb) of the residual heat boiler, and the residual oxygen concentration after the combustion of the air can also truly reflect its combustion state. Therefore, the following empirical formula can be applied to the air required for combustion:
F=1000×a×Qb×[21/(21-O2)]+b-F2 Formula Manila escort(1-1)
Qb: Steam evaporation
O2: Fluid oxygen content
Code a is the ratio of combustion air volume to evaporation volume, and its value is determined based on the characteristics of the residue in this area and the characteristics of the furnace.
b and F2 coefficients are the micro-tuning values of the ACC computer panel and are determined after actual adjustments during a period of time.
1.2 Calculation of the combustion air ratio
After obtaining the total combustion air volume (F) sent into the furnace, the air must be distributed to the inlet of the furnace in a different proportion. This calculation action becomes a “ratio calculation”.
1.3ACC calculation results and current hardSugar The connection of baby device equipment
After the ACC calculation is completed, it can be seen as: “In order to achieve the fantasy combustion state, the setting value (SV) is set to each holding element”. This calculation result must be passed through the DCS control center of the factory, and after the unified command adjustment and the required signal conversion, it will be sent to each device on site. Similarly, the return signal sent from the current site must be sent back to the ACC through the DCS for the required adjustment and correction actions, so DCS plays the interface between the ACC and the current site control equipment here.
1.4 Drying section gas inlet DCS control process
This stage control process is the calculation result received from the ACC. Through the DCS control interface, the setting value is checked by the wind adjuster, and then the signal is converted through the current positioner to the current signal that the field wind control motor can receive. The gas inlet DCS control process of the post-burning section gas adjuster is the same as that of the drying section.
In order to make the entire control system more flexible and easier to operate, the operator can make the required actual adjustments based on the actual furnace condition to sufficiently match the operating characteristics of the dregs incineration furnace. The system provides Sugar daddy with various control forms of switching designs. You can select the calculated value of the ACC or set value that is forced by the operator in the DCS. You can select the automatic or manual form, and the operator changes the operation value according to the boiler status at any time.
1.5 Oxygen Modification
When the total wind is constant, the oxygen change reacts to the change in the dregs heat value faster than the change in steam. If the oxygen amount is large at the base value, it means that the fuel amount is not small and the amount of steam generated is too low, so the combustion must be strengthened, and the feed and boiler rate will be accelerated, and vice versa.
2. Method of controlling ACC fuel inlet volume
2.1 Drying rate control
Drop is poured into the feed port, and after the push of each section of the furnace bed, it is burned one by one. Each furnace bed is pushed by a different oil pressure anus (controlled by a proportional electromagnetic valveSugar baby), so adjusting the push rate of the oil pressure anus can make theKeep the feeding volume of the residue and then control the internal combustion burning status of the furnace.
Picture 2-2 Representation diagram of the rate ratio of each section of the furnace bed 2-2
Picture 2-3 Calculation process diagram of the rate ratio ratio of each section of the furnace bed 2-3
As shown in Figure 2-2, 2-3: Burning Sugar daddy Burning section: X=30.8% Burning section Burning section Burning section Burning section Burning section
Dry section: Y=30.8%×150%=4Escort6.25% Drying section boiler rate
Supply section: Z=46.25%×25%=11.56% Supply section boiler rate
The calculations of the boiler rate in each section above do not count the modified value of the boiler residue layer height. When the normal ACC calculates the boiler speed, the modified calculation of the dryer layer height will be counted into the boiler rate calculation.
2.3 The slag layer height modification furnace rate calculation is located above the two slag layer beds in the drying and burning sections. It is equipped with a slag layer height sensor, which is composed of a wave transmitter located on the side of the furnace to emit microwaves to another true wave receiver. href=”https://philippines-sugar.net/”>Escort When the residue piled up on the boiler bed covers the microwave, a signal occurs (signal value is 1)
2.4 boiler oil pressure cylinder proportional electromagnetic valve
Sugar baby The boiler bed rate value can be responsiveUse the calculated value of the aforementioned ACC (AUTO) or switch to the manual control MV, and then pass the proportional electromagnetic valve handler in the DCS and then transfer it to the current oil pressure. Then he laughed. The cylinder electromagnetic valve adjusts the oil pressure flow rate of the oil pressure of the cylinder, changes the pushing rate of the furnace bed, and thus controls the fineness of the residue feeding volume.
3. The boiler control system
The boiler is Sugar baby has created sufficient dramatic performances. There are three sections without night spaces in a row: drying section, burning section, and burning section. The supply air volume and operating rate of each section can be adjusted.
1. Dry section. Drying of the residue includes: high-temperature combustion air in the furnace, the side walls and the top of the furnace; air drying of the high-temperature gas supplied from the lower part of the furnace; contact drying of the dregs and high-temperature combustion gas; and drying of the dregs in the middle of the residue. The application of heat from the heat wall and flame, the residue starts to dry out from the general condition, and the part produces a general condition of burning. The ignition temperature of the dry residue is generally 200°C. If the dry air above 200°C is supplied, the dry residue will catch fire and the burning will start from this door. The duration of the residue on the drying section is about 30 minutes.
2. Burning section. This is the burning middle part. The residue in the drying section is dry and heat differentiated to produce a reductive gas, which produces a lush burning flame in this section, and is static burning in the post-burning section. The boundary between the burning section and the afterburning section is called “burning full point”. Even if the characteristics of the residue change, the combustion position should be kept as constant by adjusting the boiler speed. The dregs stayed for about 30 minutes in the bu TC:
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