CN1046970A - The control method of combustion process and automatic optimal regulating system in the heat target - Google Patents

Abstract

Have two measuring instrument (9) and (10) of measuring oxygen content in the burning gases according to system of the present invention.They are positioned at the exit portion of combustion chamber (1).Instrument (9), (10) of measuring oxygen content in the burning gases link to each other with additive air adjuster (12) by switching device (11), and switch (11) can be selected instrument (9), (10) measured.In addition, instrument (9), (10) link to each other with the inlet of combustion balance adjuster (13).Two outlets of this adjuster link to each other with the additive air air blast, and adjuster can change the flow of each air blast (7), (8) as required.

Description

The control method of combustion process and automatic optimal regulating system in the heat target

The present invention relates to burning control method and automatic optimal regulating system in the heat target.The present invention is used for station boiler, with guarantee combustion process reasonably, operation best.Poland Patent specification 118383 discloses the control method and the system of combustion process in a kind of heat target, this system has the fuel-air ratio rate regulating loop of working according to the component of measured burning gases, adjust the component of fuel-air according to the oxygen content of the burning gases of measuring with instrument, the oxygen content of burning gases is constant set-point in this method.The control method of US Patent specification 3672840 described combustion processes and system take to adjust the method for air-fuel mixture component, make their component can meet the requirement of correct mixture.In above-mentioned two kinds of known methods and system, all be that the data according to burning gases change the component of sending into the ignition mixture in the combustion chamber, thereby reach the purpose of control combustion process.And burning gases component measured value is the mean value of combustion process in the combustion chamber.

Although combustion process difference in each zone in fact, the combustion process in each zone, combustion chamber can not be controlled.The method and the combustion control system that also have some to work according to the data of combustion chamber, these regulating systems are by measuring certain point in the combustion chamber, and normally the ignition temperature of its geometric center is regulated combustion process.In this case, because measured temperature only is the temperature of certain point, thereby be that local circumstance according to combustion process adjusts.From the described boiler combustion control method of DRP specification 3024401A1 as can be known, it is to control the combustion process of the bags in the radiation at length of flame place according to measuring each burner, make each burner outlet place Fire Radiation intensity identical in this way, like this, can guarantee the uniformity of combustion process in the combustion chamber.Disclosed design is the representational basis that is sampled as with burning gases, and this is sampled as the different local measured instantaneous values of boiler export, or different local combustion gas analysis mathematical mean.Because anoxic, the entrance and exit space is in the imperfect combustion situation, the sign that this will cause the emerged in operation burning to degenerate suddenly.Then, increase air capacity, so that reach the safety margins advantage point at least, and this just means at a large amount of unnecessary excess airs of stand-by boiler space existence, and heat-energy losses is very big.

The objective of the invention is to regulate combustion process, so that rationally carry out in whole boiler space combustion process.Main points of the present invention are to regulate the fundamental quantity of additive air, and itself and the oxygen content in the burning gases that combustion chamber one side records are on the same level.Simultaneously, measure in the combustion chamber asymmetry of the oxygen content reading of burning gases between 2.According to measured asymmetry, from two sources of the gas additive air is sent into the combustion chamber, it is uneven that the Flow-rate adjustment of these two sources of the gas becomes, and oxygen content uneven opposite in the imbalance of additive air source flux and the burning gases.

Two measuring instruments are housed in system of the present invention, and to be used for measuring the oxygen content of burning gases, these two measuring instruments are installed in the exit portion of combustion chamber.The instrument of measuring oxygen content in the burning gases is all linked the inlet of additive air adjuster by selector switch.In addition, the above-mentioned measuring instrument that is used for measuring the burning gases air content also links to each other with the inlet of burning symmetry adjuster, and two outlets of this adjuster link to each other with two additional drums blower fans respectively.As required, adjuster can change the flow of each blower fan.The burner case has horizontal, mobile gate, and this gate is separated into two parts with the burner case.Accompanying drawing has been represented an embodiment of system of the present invention.Wherein Fig. 1 is a system schematic, and Fig. 2 and Fig. 3 are the side view and the front views of the gate of separated combustion device case.

According to the present invention, before this method of use, should regulate the fundamental quantity of the needed additive air of combustion process.By the content of the carbon monoxide in the burning gases of both sides, continuous measurement combustion chamber, also measure the fundamental quantity that oxygen content in the burning gases is regulated additive air simultaneously.When above-mentioned amount was measured, the flow in the additive air source by regulating the both sides, combustion chamber can reduce air content in the burning gases.And above-mentioned adjusting can perhaps realize by the rotary speed that reduces the additive air air blast by partly closing the guider of the flow of regulating additive air.Can reduce oxygen content in this way, make the fundamental quantity of itself and additive air suitable, so that the burning in the control boiler approaches to occur a small amount of carbon monoxide.

This method comprises the burning gases oxygen content of measuring the combustion chamber point, again according to above-mentioned measurement, regulates the required basic additive air of best combustion process.Additive air is provided by two sources of the gas.According to above-mentioned measurement, the flow of each source of the gas is transferred to identical so that total air can satisfy burning, the controlled basic need amount of proofreading and correct.Simultaneously, the content of oxygen in the second point measurement burning gases of combustion chamber also.Above-mentioned each measurement point is set at that split the combustion chamber, different two halves, and the variation of the air capacity that each measurement point reflects means that it is uneven that the additive air of supplying with the combustion chamber distributes.According to the method, the oxygenation measurement value of each measurement point is compared.

If the content imbalance of additive air in the combustion chamber when measuring can change the flow in additive air source.In this way, can obtain unbalanced flow, this uneven flow is opposite with the degree of unbalancedness of oxygen content in the burning gases.Therefore, the burning of the whole bags is balanced.

There is a burner case 21 outside, combustion chamber, and the powder-air conduit 3 that fuel-air mixture is led to combustion chamber 1 is housed in this burner case.For this reason, adopted the burner 4 that has overfire air jet 5 in the wall of combustion chamber 1, additive air flows to combustion chamber 1 from burner case 2 by overfire air jet 5.Additive air is admitted to the burner case 2 by conduit 6 from the two ends of burner case 2: first end of burner case 2 links to each other with the first additive air air blast 7, and second end links to each other with the second additive air air blast 8.Each zone line of half of 1 has been installed measuring instrument 9,10 in the combustion chamber, is used for measuring the air content in the burning gases.Measuring instrument 9,10 selects the switch 11 of measuring instrument 9,10 to link to each other with being used for, and switch 11 links to each other with the inlet of additive air adjuster 12, and the outlet of adjuster 12 links to each other with 8 with additive air air blast 7.The instrument 9,10 of measuring air content in the burning gases also links to each other with the inlet of burning symmetry adjuster 13.Burning symmetry adjuster 13 has two outlets, and these two outlets link to each other with additive air air blast 7,8.Horizontal, removable gate 14 are arranged in burner case 2, and it is with burner case 2 separated into two parts, and gate 14 has weight 15, and this gate can be from the upright position to both direction deflection angle 16.

Burning-air mixture is admitted in the burner 4, the mixture of Here it is fuel and primary air.This mixture leaves in burner 4 flow into combustor 1, and burning in combustion chamber 1.For fuel combustion, oxygen in the primary air and oxygen in the additive air have been used, above-mentioned additive air is sent burner case 2 to by air blast 7 and 8, and by additive air nozzle 5 flow into combustor 1, mixes with the fuel-air mixture that flows out burner 4 in combustion chamber 1.The air capacity that measuring instrument 9,10 is measured in the burning gases.This measured value is sent into adjuster 12 through switch 11.Adjuster 12 demonstrates the measured value of instrument 9 or instrument 10, and the flow according to these measured value adjuster 12 each air blasts 7 of adjustment and 8 equates with the flow of keeping each air blast 7 and 8.Burning symmetry adjuster 13 receives the signal that measuring instrument 9 and 10 is sent simultaneously, and they are compared.In the burning gases of the halves of combustion chamber 1 oxygen content not simultaneously, adjuster 13 sends signal and gives corresponding air blast 7 or 8, to change its flow.By increasing or reducing arbitrary air blast 7 or 8 additive airs of being sent to, make that the two parts in the combustion chamber 1 can balancedly burn with reasonable manner.In order to eliminate the interaction between the additive air that blasts by air blast 7 and 8, with horizontal, removable gate 14 with burner case 2 separated into two parts.The place that gate 14 is laid should make when quitting work for one in air blast 7 or 8, additive air can be blasted in the burner case 2 by air blast 7 or 8 runnings.

When quitting work for one in air blast 7 or 8, gate 14 deflections and opening automatically, air flows in two parts of burner case 2.After repairing out of order air blast, burner case 2 two-part pressure equate that weight 15 makes gate 14 move on to the upright position.

Claims (3)

1, the best approach that is used for the heat target combustion process, this method changes the additive air amount according to the burning gases oxygen content of measuring, and it is characterized in that the additive air fundamental quantity is adjusted on the level of the oxygen content from the measured burning gases of combustion chamber one survey.Simultaneously between 2 in the combustion chamber, measure the asymmetry of oxygen content reading in the burning gases, asymmetry according to reading, become unbalanced source of the gas to combustion chamber feeding additional air by two its Flow-rate adjustment, the imbalance of above-mentioned gas source and flow amount is opposite with oxygen content degree of unbalancedness in the burning gases.

2, the fuel-air mixture component of supplying with the combustion chamber by oxygen content and change in the burning gases in the measurement combustion chamber carries out the system that automatic optimal is regulated to the combustion process of heat target, the adjuster that comprises oxygen content in the fuel-air mixture, the adjuster inlet links to each other with the measuring instrument of measuring the burning gases oxygen content, the adjuster outlet follows the air blast that additive air is blasted in the burner case to link to each other, it is characterized in that this system is equipped with at least two measuring instruments of measuring oxygen in the burning gases, they are installed in the exit portion of combustion chamber, an inlet with additive air adjuster (12) in these instrument (9 or 10) links to each other, the measuring instrument (9 of oxygen in the above-mentioned measurement burning gases, 10) also link to each other with burning symmetry adjuster (13), the outlet of symmetry adjuster has horizontal with the continuous burner case of additive air air blast, removable gate (14), this gate is arranged on and will so burns device case place divided into two parts, and these two parts provide air by air blast (7) or (8) respectively.

3, system according to claim 2 is characterized in that measuring the measuring instrument (9) of air capacity in the burning gases, (10) are connected to additive air adjuster (12) by switch (11) porch.

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