CN105247308B - Method for operating a regenerative heating industrial boiler, control device and industrial boiler - Google Patents

Abstract

The invention relates to a method for the controlled operation of a regenerative-heating industrial boiler (100) having a furnace chamber (10), preferably for controlling the fuel energy input of a fuel having a fluctuating calorific value into the furnace chamber (10), having the following steps: -injecting fuel into the furnace chamber (10) by means of at least one fuel injector (20, 20'), which is configured for injecting fuel, in particular fuel that is virtually free of combustion air, -periodically alternately feeding combustion air into the furnace chamber (10) for a first period duration on the one hand and discharging exhaust gas (AG) from the furnace chamber (10) separately from the fuel for a second period duration on the other hand, wherein-the feeding of combustion air or a similar oxidizing agent is regulated and the remaining oxygen in the exhaust gas is determined. According to the invention: -determining the oxygen consumption occurring in the combustion of the fuel from the input combustion air and the remaining oxygen, and-using the oxygen consumption as a measure of the energy of the fuel used, wherein the fuel flow for injection is adjusted such that the oxygen consumption is controlled to a predetermined oxygen consumption value.

Description

Method for operating a regenerative heating industrial boiler, control device and industrial boiler

technical field

The invention relates to a method according to the preamble of claim 1 for the controlled operation of a regeneratively heated industrial boiler, in particular with a melting tank, in particular for glass, and a method according to the preamble of claim 15 A control device configured to perform the method. The invention also relates to an industrial boiler according to the preamble of claim 17 .

Background technique

In principle, industrial boilers are not restricted to glass production. Industrial boilers of the type mentioned at the outset can also be used, for example, in metal production or the like. However, regenerative industrial boilers of the type mentioned at the outset have proven to be particularly suitable for glassmaking for melting glass.

So far, only PID controllers have been entrusted to control the regenerative glass melting furnace, that is, usually by means of the control of the upper furnace in the furnace chamber as the controlled object. The purpose of the PID controller is to control the temperature of the upper furnace and its output terminal or representative The amount of fuel itself, or represents the amount of combustion air that can be adjusted with the amount of fuel.

The guiding variable for determining the energy application of the glass melting bath is usually the temperature of one or more thermocouples in the dome of the melting furnace. Due to the high heat storage capacity of the boiler and the melt, the temperature changes only slowly and only after a few hours does a significant change occur. Therefore, the energy flow input with the fuel flow is usually continuously controlled as a subordinate control loop. If the thermal value can be measured well online, for example in the case of fuel natural gas, fluctuations in the thermal value can be quickly equalized by correspondingly changing the fuel quantity itself, so that the fuel feed flow can be constantly controlled with sufficient precision.

However, conventional control methods either incorrectly assume a constant amount of uncontrolled air intake, or only modify the combustion air input based on manual or continuously measured measurements of oxygen remaining in the exhaust. However, optimal control dynamics cannot be achieved with it due to its partially nonlinear relationship with the combustion air. In particular, this approach cannot evaluate low-stoichiometric heating ranges, since the effective control behavior can no longer be explained from a comparison of different process states with 0% residual oxygen in each case.

Therefore, it is suggested in the article by Hemman et al. (Technical Report XP-00121591) "Advanced combustion control–the basis for NOx reduction and energy saving in glass tank furnaces" Glass Sci.Technol.77(2004) No.6 pp. 306 to 311 Use pure Lambda (also known as "excess air ratio" or "air surplus"; symbol λ) control, that is, control the ratio of combustion air to the stoichiometric minimum of combustion air so that infiltration into the air is minimized or equalization is impossible Avoid penetration of air (Falschluft). It is recommended to install a zirconia Lambda (also known as "excess air factor" or "air surplus"; symbol λ) sensor in the regenerator probe. It is also recommended to combine PID control with predictive control. Infiltration air is known for the first time as a typical uncontrollable input of cold air in boilers and regenerators so that it participates in combustion and cannot be harvested by proportional control.

Fuels whose thermal value cannot be measured online, however, have large uncontrollable fluctuations in the thermal value, and furthermore do not offer the possibility of quickly equalizing the thermal value fluctuations by correspondingly changing the fuel quantity itself. The result is significantly greater mass-induced temperature fluctuations and/or energy efficiency fluctuations. In particular, such fuels are being used more and more in the context of fuel depletion which is noticeable worldwide.

An improved control of industrial boilers of the type mentioned at the outset is desired, taking into account the long reaction times between a change in the air ratio and a change in the measured value of a consequently measurable exhaust gas analysis measurement, which are typical in industrial boilers with regenerative heating plan. It is also desirable to equalize uncontrollable fluctuations in the thermal value relatively more rapidly when using fuels for which the thermal value cannot be measured online.

Contents of the invention

The technical problem to be solved by the present invention is to provide an improved method for the controlled operation of a regeneratively heated industrial boiler, an improved control device for carrying out the method and an improved industrial boiler. In particular, the disadvantageous aspects of the prior art described above should be avoided as much as possible, at least one of the problems described above. In particular, a device and a method are to be provided by means of which uncontrollable fluctuations in the heating value can be equalized when using fuels with an indeterminate heating value; in particular, the equalization can make the energy input of the fuel into the furnace chamber as constant as possible. At least one alternative solution to the solutions known in the prior art should be suggested.

With regard to this method, the above-mentioned technical problem can be solved by means of the invention with a method of the type mentioned at the outset, wherein the characterizing features of claim 1 are provided according to the invention. The method is preferably used for controlling the fuel energy input of fuels with fluctuating thermal values into the furnace chamber, in particular for controlling the relatively constant fuel energy input of fuels with fluctuating thermal values into the furnace chamber itself. To solve the above-mentioned technical problem, the invention proposes a control device according to claim 15 and an industrial boiler according to claim 17 .

Fuel is to be understood in particular as gas. Other fuels such as oil can also be used to run industrial boilers. Fuels include, in particular, fuels with an undefined heating value. These are in particular solid or liquid fuels which generally have a relatively high carbon content and/or a relatively high hydrogen content, in particular a carbon content of well above 80% or a hydrogen content of well above 10%. Here, for example, heavy oil as a representative of liquid fuel or coke (petroleum coke, petcoke) as a representative of solid fuel. Although these fuels have a relatively high energy content, disadvantages are, on the one hand, their high _CO2 emissions upon combustion and their relatively high NOx and sulfur exhaust emissions. In particular, these fuels with uncontrollable fluctuations in calorific value mainly exist in relatively undefined combustion regimes. Coke exists, for example, as dust with different particle sizes and rock content, which has to be partly comminuted, mixed with compressed air, and fed to the burner as sticky dust. The input form and thermal value of the fuel present form to the burner or injector are undefined or barely measurable.

Injectors are to be understood in particular as nozzle arrangements which are designed to inject fuel into the inlet section or furnace chamber directly upstream of the furnace chamber, in particular separately from the combustion air. The mixing of combustion air and fuel takes place in the furnace chamber. The furnace chamber has in particular an upper furnace and a lower furnace. The lower furnace has, in particular, a glass melting pool and the like.

On the one hand, the combustion air is supplied to the furnace chamber for the first cycle duration and, on the other hand, the exhaust gas is discharged from the furnace chamber separately from the fuel for the second cycle duration, preferably in the left heat accumulator associated with the at least one fuel injector. and one of the right regenerators, which is configured for regenerative storage of heat from the exhaust gases and transfer of heat to the combustion air.

The heat accumulators referred to as left and right heat accumulators are not restricted to a positional arrangement, but are only required by the usual technical language. The designation can also be chosen otherwise, eg first and second heat accumulator. The heat accumulator can be arranged relative to the glass melting tank in the flow direction or perpendicularly to the flow direction of the glass. One accumulator can correspond to multiple injectors. The heat accumulator can also be understood as the heat accumulator part corresponding to a single injector or the like.

The residual oxygen in the exhaust gas is particularly preferably determined by measuring the oxygen and/or by determining the oxygen from the exhaust gas air residual (Lambda; also known as “excess air ratio” or “air residual”; symbol λ). In particular, determine the residual oxygen and/or combustion air content.

The solution of the present invention can be built into the available furnace temperature control method. The present invention contemplates that although it is possible to match the fuel flow with respect to the thermal value of the fuel for controlling the fuel energy input to the industrial boiler, the present invention also recognizes that the thermal value can only be determined relatively reliably or preset within a reliable range of assumptions. Significant. In a preferred extension, it has therefore also proven to be particularly advantageous if the characteristic composition of the fuel is stored as an operating point with a reference thermodynamic value and the composition is changed proportionally to the changing thermodynamic value. This can assist in presetting some solid assumptions. In the case of fuels with uncontrollable fluctuations in the thermal value, such as coke or other oily dust, the assumption of the thermal value based on the composition of the fuel and its chemical properties has proven to be flawed or unpromising as an individual measure. The invention recognizes that in this case oxygen consumption can be determined as a reliable measure of fuel energy used, although some unmeasured values relate to the relationship between oxygen consumption and energy input of fuel energy.

The invention recognizes that in the case of fuels with uncontrollable fluctuations in the thermal value, the energy input into the furnace chamber can be adapted by varying the input quantity (fuel flow) carried by the fuel. To an extended extent, this can be achieved, for example, by increasing the air-dust mixture with coke as oily dust or by reducing the air-dust mixture with coke as oily dust. Likewise, the thermodynamic value of the fuel is no longer used as a regulating variable to measure the energy input, but the oxygen consumption. The oxygen consumption is also determined from the comparison with the incoming combustion air and from the measured residual oxygen in the exhaust gas.

The solution according to the invention proves that in the case of fuels of uncontrollable thermal value quality, the assumed proportionality of the oxygen consumption to the fuel energy is relatively reliable. In particular, the assumption of a direct proportionality between oxygen consumption and fuel energy used proves to be relatively stable in the case of fuels of uncontrollable thermal value quality.

The method according to the solution of the invention has proven to be relatively robust, independent of how the oxygen consumption is determined. The oxygen consumption can be determined, for example, from the supply of combustion air and the determination of the residual oxygen. The determination of the residual oxygen can in principle again be performed as a direct oxygen measurement or preferably (in particular because there are often less fluctuations) from the exhaust air residual (Lambda value).

In addition, the present invention recognizes that quickly equalizing all fuel energy used by input fuel quantities can actually translate directly into a response to an equally relatively rapid signal of residual oxygen or Lambda value. This can in particular be largely independent of furnace temperature trends, which last for a very long time period of several hours, while the fuel energy used can be adapted to a time period of several minutes, ie almost in real time.

Further preferred developments of the invention are given in the subclaims and specify preferred possibilities for realizing the solution explained above within the scope of the technical problem and with regard to further advantages.

The fuel flow for injection is preferably regulated by means of an adaptation of the compressed air quantity and/or the fuel quantity and/or the fuel mixture. This can be done based on equipment prerequisites or knowledge of fuel composition.

The characteristic composition of the fuel is preferably stored as an operating point and changes in proportion to the changing thermal value. This can be exploited to advantage, especially if a suitable range of defined fuel burn values is used. Preferably, the best assumptions can be made from the fuel energy and can be used to determine pilot control values or other variables involved in the process equation. In a particularly preferred extension, the assumption that oxygen consumption is approximately proportional to fuel energy input has proven to be a credible and relatively reliable assumption. This may for example be used for relatively similar fuel compositions, for example fuel compositions having a carbon content between 80% and 90% or between 90% and 100% carbon content or between 80% and 100% carbon content Or a carbon content between 85% and 95% or other relatively similar carbon content. Within such a range n, the thermodynamic value can be estimated initially using some reliable assumptions with corresponding proportionality coefficients as measures. In principle, the measure between the oxygen consumption and the fuel energy used can also be determined by means of other or additional criteria for the carbon content, all of which are described here as examples only.

Preferably a nominal oxygen consumption is set and the actual oxygen consumption is controlled under conditions matching the fuel energy used, in particular the fuel flow. This expansion advantageously directly utilizes the important variable of the oxygen consumption and is thus directly relevant for the fuel energy used.

Additionally or alternatively, a target exhaust air residue (SOLL-LAMBDA) is preferably set and controlled under the condition of adaptation to the fuel energy used, in particular the fuel flow. This method preferably directly utilizes the measurement signal of the Lambda probe on the heat exchanger dome, and has a relatively small fluctuation amplitude.

It is preferable to keep the combustion air input constant, which results in relatively stable control conditions when matching fuel flow. The feed of combustion air is preferably constantly controlled by means of a control circuit, taking into account the technically required air surplus, and the fuel flow is adjusted so that the specified exhaust gas air surplus (SOLL-LAMBDA) is followed in the exhaust gas directly downstream of the furnace chamber. Oxygen remaining.

In principle, a time-transient spread of the combustion air is also acceptable, in particular if it covers a longer time interval than the time interval of the matching fuel flow. This makes it possible, for example, to automatically regulate the supply of combustion air, in particular automatically by means of a control loop.

In a particularly preferred development, a method is provided for controlling a constant fuel energy input of a fuel with fluctuating thermal values to a melting furnace, wherein the constant control is carried out by means of a control loop taking into account the technically required remaining air The input of oxidant oxygen. In particular within the scope of the concept of the invention, the fuel flow is adjusted at any time such that a residual oxygen in the exhaust gas directly downstream of the combustion chamber is observed, which is determined according to the desired air residual.

It has been found to be particularly advantageous that the described concept can be used to keep the infiltration air into the furnace chamber relatively small or relatively constant and equalized, regardless of the heating direction, ie regardless of the heating from the left and from the right. A preferred development of the invention assumes that, within the scope of the concept of the invention, it is particularly advantageous that the oxygen consumption can be reliably determined for the determination or determination of the residual oxygen without erroneous influences caused by the penetration of air.

Preferably, in particular constantly, the furnace pressure in the furnace chamber is kept above a furnace pressure threshold. In another particularly preferred development, a method is provided in which the pressure in the combustion chamber is maintained above a minimum pressure value.

The lowest pressure value is preferably defined as the furnace pressure at which the residual oxygen value in the exhaust gas after the combustion chamber is the same for the left and right flames.

Additionally or alternatively, the minimum pressure value is preferably defined as the difference in the oxygen residual value between the left heating and the right heating which is no longer significantly reduced by increasing the furnace pressure.

A particularly preferred development recognizes that the method for controlling the supply of combustion air to regeneratively heated industrial boilers should be based on a particularly continuous analysis and compensation of uncontrolled infiltration air losses or uncontrollable infiltration air inflows with regard to combustion . This corresponds in particular to glass melting tanks with the aim of controlled near-stoichiometric or even controlled low-stoichiometric heating with a setpoint value for a constant, predeterminable residual air quantity Lambda. According to a development, the air infiltration indicator shows whether uncontrolled infiltration air should be or can be equalized by adjusting the combustion air, or whether uncontrollable infiltration air should or can be suppressed only by increasing the furnace pressure.

In a particularly preferred extended range it has proven to be advantageous to equalize the thermal asymmetry of the heat accumulator with an output of the active symmetry control for the indication of the infiltration air, ie to use an output as an indicator of whether or not to allow an uncontrolled equalization by matching the combustion air The standard of air or uncontrollable air can be suppressed only by increasing the furnace pressure. The first regulating unit is preferably designed as a throttle in the combustion air supply, which is designed to control the flow of combustion air. The second regulating unit is preferably designed as a gate in the exhaust gas output, for example a reversing gate, which is designed to build up a counterpressure relative to the furnace pressure.

In a particularly preferred development of the method for automatic control of the combustion air feed to a regenerative industrial boiler, in particular a regenerative fired glass melting tank, the combustion air flow is automatically controlled by a known PID controller according to The fuel quantity, the stoichiometric air requirement of this fuel multiplied by the remaining air quantity Lambda specified as the target variable minus the preferably continuously determined uncontrollable infiltration air input quantity from outside the industrial boiler forms the target value. This control preferably corresponds to SP_Luft=SP_Lambda*L _MIN *Brennstoff−XFA. The uncontrollable infiltration air input is preferably determined continuously by means of combustion calculations based on a preferably continuously operating exhaust gas analysis device.

The analytical device is designed in particular in the form of a lambda probe, which is preferably implemented as a known zirconia probe. It is particularly advantageous to divide the residual air quantity Lambda(λ _SOLL ) of the combustion air, which is preset as a target variable, by the fuel quantity and form a continuously corrected air-fuel ratio which is passed to the lambda controller of the control circuit. For better determination of the remaining air characteristic, it is particularly preferred to form the air ratios for a plurality of simultaneously used fuels in such a way that they are arranged relative to one another in relation to the stoichiometric air requirements of the individual fuels. As a result, the oxygen supply can advantageously be maintained constant with varying fuel contents. For example, to avoid the disadvantages of the conventional method, the process value of the actual air _residue , called Air remaining Lambda as process value:

Here, the properties of the fuel and the influence of _CO2 can be included in the constants const.1 and const.2 according to the separation of carbonates contained in the feedstock.

Preferably in another control loop for temperature control:

- by the furnace chamber temperature as a control parameter, and

- a first controller for the furnace chamber temperature, in particular a PID controller, and

- A first adjustable control variable in the form of a fuel flow and/or a combustion air flow is set by a control unit assigned to the first controller. The lower-level temperature control ensures in an efficient manner the development of the furnace chamber temperature that takes place over a longer period of time.

Description of drawings

Embodiments of the present invention are described below in conjunction with the accompanying drawings. The figures not only show the exemplary embodiment to scale, but also show the part of the figures used for explanation in a schematic and/or slightly distorted manner. Reference is made to the relevant prior art for supplements to the teachings which can be directly discerned from the drawings. It is conceivable here that various modifications and changes may be made with respect to the shape and details of the embodiments without departing from the general idea of the invention. The features of the invention disclosed in the description, the drawing and the claims can be essential to the development of the invention both individually and in any combination. Furthermore, all combinations of at least two of the features disclosed in the description, drawings and/or claims fall within the scope of the invention. The general idea of the invention is not limited to the specific forms or details of the preferred embodiments shown and described below, nor to what is defined with respect to what is claimed in the claims. For the stated measuring ranges, values lying within the stated limits are also to be disclosed as limit values and can be used and claimed arbitrarily.

Further advantages, features and details of the invention are obtained from the preferred embodiments described below and in conjunction with the accompanying drawings, in which:

1 shows a schematic view of a regenerative heating industrial boiler with left and right heat accumulators according to a particularly preferred embodiment, wherein a control device with a lambda control module is provided according to the solution of the invention;

Figure 2 shows a flow chart for illustrating the flow of a preferred embodiment of the method;

FIG. 3 shows an example diagram of a process data curve in the case of a furnace chamber of a glass melting pool, wherein the furnace pressure of the furnace chamber is varied from below a minimum pressure value to above a minimum pressure value for the application of the method in FIG. 2 , This makes it possible to equalize the active air ratio (air to gas) in the exhaust gases of the different flame sides, ie to reduce the difference in oxygen values between left heating and right heating by correspondingly increasing the furnace pressure.

detailed description

FIG. 1 shows a simplified diagram of a regenerative heating industrial boiler 100 with a furnace chamber 10 , the upper furnace chamber 1 being controlled as the controlled object, wherein the lower furnace chamber 2 has a glass melting tank (not shown in detail). The glass contained in the glass melting bath is heated by the furnace chamber 10 above the melting temperature, and is melted and properly processed for the manufacture of glass bottles and the like. The industrial boiler 100 is heated here, the upper furnace 1 is injected with fuel here in the form of gas via a plurality of side-mounted fuel injectors 20 . The fuel injector 20 here represents the left injector 20 . The other fuel injector 20' represents here the right injector 20'. For reasons of simplification, the same reference numbers are used below for identical or similar components or components with the same or similar function. For example, a number of six syringes 20 , 20 ′ can be arranged on the left or right, respectively. The combustion cycle shown in FIG. 1 injects gas with almost no combustion air into the upper furnace 1 via the fuel injector 20 . Above the fuel injector 20 , preheated combustion air VB is supplied to the upper furnace 1 through the left opening 30 . The combustion air from the opening 30 is mixed with the gas injected from the fuel injector 20 in the upper furnace 1 and used to form the lower furnace covering flame 40 , which is shown symbolically here. The image of FIG. 1 shows the industrial boiler 100 in a regenerative combustion state through the left regenerator 50 and the left injector 20 . These and the openings 30 are configured so that the gas supplied through the injector 20 is mixed with the combustion air VB of the left regenerator in the upper furnace 1 in sufficient near-stoichiometric or low-stoichiometric quantities. The left-hand combustion operating state of the upper furnace 1 shown in FIG. 1 lasts for a first period, for example, from 20 to 40 minutes with gas injection via the left injector 20 and combustion air VB via the left regenerator 50 duration. During the duration of the first cycle, the combustion air VB is supplied to the upper furnace 1 into the furnace chamber 10 separately from the gas 20 . During the duration of the first cycle, the exhaust gas AG is fed from the upper furnace 1 via the right opening 30 ′ into the right heat accumulator 50 ′ and heated.

In the second operating state, the combustion of the upper furnace 1 is reversed for a second cycle duration of similar length. For this purpose, the combustion air VB is supplied to the upper furnace 1 via the right heat accumulator 50' and at the same time the gas from the right injector 20' is supplied, wherein the combustion air VB is then absorbed by the exhaust gas AG in the heat accumulator 50' for the duration of the first cycle. heat of deposition.

In principle, the fuel flow and/or the combustion air flow is controlled via the temperature control module 400 of the control device 1000 of the industrial boiler 100 . For this, in principle a PID controller can be used in the temperature control module 400 according to which the temperature of the oven chamber is increased with an increased fuel flow and/or combustion air flow or with a reduced fuel flow and/or combustion air flow. Reduce oven temperature. The temperature values of the regenerator probe 51 or 51 ′ or the upper furnace chamber 1 are transmitted to the temperature control module 400 via suitable temperature probes 52 , 52 ′, 53 , which are in any case partly related to the measurement Proper Lambda Probe Binding for Fuel to Air Ratio.

The control device 1000 also has a symmetrical control module 300 which is designed here to influence the heat transfer between the first and the second heat accumulator 50 , 50 ′. This is done here by means of a heat transfer variable in the form of a time period ±Δt, whereby the second cycle duration t is extended for the cooler of the first and second heat accumulators 50, 50' and/or for the first and second heat accumulators 50, 50' The second cycle duration t is shortened for the hotter of the second heat accumulator 50, 50', or the first cycle duration t and t are shortened for the cooler of the first and second heat accumulator 50, 50'. / Or the first cycle duration t is extended for the warmer of the first and second heat accumulators 50 , 50 ′. A suitable regulating unit in the form of a timer is here coupled to the symmetry control module 300 and is able to shorten or lengthen the first and second period duration t according to the indications of the symmetry control module 300, which can here store heat on the left The duration of the cycle is extended by the time period ±Δt in the storage device 50 or the right heat accumulator 50'.

In addition, for the automatic control of the combustion air input of the regenerative industrial boiler 100 with the regenerative combustion glass melting tank, the combustion air flow is automatically controlled by the PID controller of the known lambda control module 200 . Depending on the fuel quantity, the product of its stoichiometric air requirement and the remaining air quantity λ _SOLL specified as a target variable minus the continuously determined uncontrollable air input quantity from outside the industrial boiler forms the setpoint value of the PID controller. The determination of the uncontrollable air input for the solution according to the invention is carried out continuously by means of combustion calculations based on a continuously operating exhaust gas analysis device, here combined with temperature probes 52 , 52 ′, 53 from known zirconia probes. constitute. At operating temperatures between 700 and 1500°C, the zirconium probe has a lifetime of about 3 years, up to 8 years in the best case. Good life is sometimes achieved even under extremely life-shortening conditions or exhaust gas pollution due to heavy metal oxides. Decisive for this is a regular service in addition to a robust, industrially suitable implementation. For this purpose the measuring signal of the zirconia probe is sufficiently stable and reproducible to be used as the basis for an automatic control.

The control by means of the lambda control module 200 described above will be referred to as "Lambda control" hereinafter. In principle, the remaining air quantity λ is defined as the ratio of the actually available air (ie the controllable air quantity plus the infiltrated air) divided by the stoichiometric minimum air requirement of the current fuel quantity.

Even for fuel mixtures such as gas and oil, the current process value λ is determined directly from the measurement (mV) of the zirconia probe, even in the low stoichiometric range λ<1. Here, the cell voltage from zero to 200 mV is a measure for a decreasing oxygen content from 20.94% down to 0%, while increasing the cell voltage from 200 mV to about 800 mV is a measure for an increasing CO content in the conversely continuing decreasing range.

A relatively good knowledge of the chemical composition of the fuel is an advantageous prerequisite in principle for determining the process value λ from the measurement results of the zirconia probe. However, gas chromatographs are only available online in special cases of luxury. For fluctuating heating values, the characteristic composition of the fuel can be stored as an "operating point" and proportionally varied as the heating value changes.

In the case of large uncontrollable fluctuations of the thermodynamic value, and if this results in an uncontrollable change of the fuel quantity, significantly greater fluctuations of the mass-dependent temperature and/or energy efficiency result. According to the solution of the above embodiment, this technical problem can be solved under the first condition, that is, by using the oxygen required for combustion as a measure for the energy of the fuel used for the fuel composition which is unstable and cannot be measured online, and adjusting at any time Fuel flow such that a pre-settable amount of oxygen equivalent to energy demand is controlled on demand. For this purpose, the fuel flow is regulated at any time with a constant feed of oxidant oxygen, so that a predetermined residual value of oxygen is maintained in the exhaust gas downstream of the combustion chamber.

It was found that in the case of such an uncontrollably varying fuel composition, the oxygen demand of the fuel however rises and falls well in proportion to its thermal value, so that the quotient of the fuel's oxygen demand and thermal value can be compared to a practical control technique Applying a constant treatment: In other words, the oxygen demand per energy unit is suitable for this case to be treated as a constant.

Based on this, the measurable residual oxygen at the output of the combustion chamber can be used as a control variable in order to keep the energy input to the melting furnace constant when the conditions for a sufficiently precise and reproducible measurement and control of the gas input or the oxygen input are first met, The latter usually meet achievable requirements.

As a second condition, the solution according to the present embodiment should set the furnace pressure in the combustion chamber so high that an uncontrolled air supply is reliably suppressed by the infiltration of air into the furnace chamber. Thus, the furnace pressure is high enough when the furnace pressure continues to rise to no longer reduce the uncontrolled air ingress.

It was found that too low a furnace pressure is typically accompanied by a difference in residual oxygen between left and right firings, and increasing the furnace pressure significantly reduces this difference. The stability limit of the furnace pressure is then precisely reached when the difference in residual oxygen between the left-hand and right-hand combustion is completely eliminated, or the difference can no longer be reduced by further increasing the furnace pressure.

If by continuing to increase the furnace pressure it is no longer possible to reduce the difference in residual oxygen between the left and right combustions, this is obviously caused by air ingress or air loss through the bottom area of the regenerator and can occur within a few hours to The time span of days is assumed to be constant. This "stabilization", ie the amount of uncontrollable air ingress (infiltration air) which is not variable by varying the furnace pressure, enables the determination of infiltration air on the basis of long-term averages of operating data, for example over several days.

In general, based on a fuel characteristic composition stored for a fluctuating thermal value as the "operating point" and which varies in proportion to the changing thermal value and/or for fuel compositions which are particularly unstable and cannot be measured online the combustion used Scheme of required oxygen as a measure of fuel energy used, where in the approach described above, the fuel flow is adjusted at any time such that a pre-settable amount of oxygen is controlled on demand and is equivalent to the energy demand, combustion calculations (for gas Also for fuel oils) dimensionless fuel characteristic values are provided, and the real air volume, exhaust gas volume, exhaust gas composition and (here of additional interest) infiltrated air XF are given below as the air determined at the probe with the controllable difference in air flow.

In contrast to the measured value O ₂ %, the measured process value λ is provided in the entire range of technical interest 1.5>λ>0.96 and is directly linear to the remaining or missing gas. This enables an efficient control which can determine the missing or remaining air in a targeted manner without having to worry about the temporal behavior of the controlled object. Setpoint value λ _SOLL is set relative to process value λ _IST , which can be non-linearly converted into a desired O ₂ % value and vice versa.

In principle, in this embodiment, the Lambda control means:

-Currently determined to infiltrate air and make it visible

- Inhibit or reduce air infiltration

- Balance the inevitable infiltration of air.

Which is the best value depends on the nature of the combustion chamber and the requirements on the melted product, in most cases a Lambda value between λ = 1.04...1.05 is a good value, corresponding to an _O2 between 0.8 and 1.0% %value.

Specifically, in order to avoid the disadvantages of conventional methods, the solution of the present invention follows firstly the process of determining the actual air surplus under the condition of using combustion calculations based on the continuous exhaust gas analysis results of the measured values _O2 % and CO% on the regenerator probe value, according to the air residual value λ as the process value (actual value) is expressed as:

Among them, the nature of the fuel and the influence of _CO2 are included in the constants const.1 and const.2 according to the separation of the carbonates contained in the feedstock.

Unlike the residual oxygen O ₂ %, the process value PV_Lambda obtained in this way is also in the low stoichiometric range, i.e.

At PV_Lambda<1, the combustion relationship is suitable for evaluation and control and is linear with the air volume over the entire technical range of interest. Due to this linearity a significantly better and more targeted control is achieved as a control towards the residual oxygen value O 2 %.

The sum of the uncontrolled air loss and the uncontrolled air intake can thus be clearly determined as a control disturbance variable as:

XF=PV_Lambda×LMIN×fuel flow-PV_combustion air

The process value PV_combustion air of the controlled combustion air flow and the stoichiometric minimum air LMIN of the fuel depend only on the chemical composition of the fuel.

The variable XF called infiltration air contains the sum of all disturbances and external influences on the combustion air balance. The disturbance variable penetration air XF is continuously determined here as a process variable. This can then be optimally suppressed by the high furnace pressure and the sealing of the boiler, and the origin of the remaining unavoidable fractions can be analyzed in order to determine reliable control limits.

Continuing first with reference to Figure 1, infiltration air sources can be analyzed online for technical control characteristics by evaluating the short-term and long-term trends of the lambda signal and thermal traces of the infiltration air in boilers and regenerators. Sources of infiltration air may be:

(A) The inaccuracies in measuring the gas flow or the amount of fuel produce computationally a deviation in the gas balance which, like real infiltration air, has the same effect on both flame sides, and when comparing devices with significantly different fuel inputs Visible at different operating points.

(B) "Drifting infiltration air", eg dirtier and lower gas volume measurements over several weeks show effects like infiltration air and can also be corrected automatically.

The influence of the systematic deviations (A) and (B) of the combustion air mass measurement on the disturbance variable XF is naturally the same for both flame sides and is determined by comparing two or more operating states with different fuel inputs. Such systematic deviations in the measurement of the combustion air quantity can be corrected and compensated for until eliminated by adaptation of the combustion air.

(C) Air loss, i.e. the short-circuit flow of part of the gas due to a leaky reversing gate, is marked directly in the exhaust flow by a negative infiltration air value plus a decreasing trend of the Lambda value with respect to the duration of the combustion cycle, typically also Occurrences of varying or sporadically changing processes, but not all.

It was found that the loss of air (C) due to a leaky reversing gate can be identified by the downward trend of the process parameter oxygen or air infiltration. Air loss can be eliminated by sealing the reversing gate and can be compensated indefinitely by matching the combustion air up to the seal.

(D) The infiltration air into the accumulator is typically laterally different and occurs in the bottom region of the chamber where the strongest low pressure of about -20 Pa prevails, i.e. the infiltration air occurring here appears in the accumulator as The gas is heated or cooled together as conventionally measured.

Compensating the uncontrollable air by changing the amount of combustion air does not cause symmetry interference between the left and right regenerators, but instead improves the thermal symmetry of the regenerator, so that it can be identified that the uncontrollable air enters the bottom of the regenerator ( D). The unavoidable part, which cannot be avoided by sealing the heat accumulator, can be compensated indefinitely by matching the combustion air.

(E) The infiltration of air into the furnace chamber may be different on the flame side due to the influence of the pressure field in the boiler. In principle, this can also be the same on the flame side; with a different infiltration air into the upper furnace on the flame side, this leads to a further increase in thermal asymmetry with air compensation. Irrespective of the infiltration of different or identical flame sides, infiltration air compensation leads to an average rise in the regenerator temperature: the cold air that does not take part in heating in the regenerator absorbs heat from the furnace chamber and emerges as hot exhaust air in the In the opposite heat accumulator, it is marked by the temperature rise of the heat accumulator.

(F) The less this air participates in combustion, the more pronounced the negative effect will be.

The entry of uncontrollable air (E) and (F) in the furnace chamber conversely causes a typical disturbance of the regenerator temperature balance between the left and right regenerators, try to compensate for these uncontrollables in the furnace chamber by matching the combustion air volume The air XF causes the thermal asymmetry of the regenerator to become larger and causes the temperature of the regenerator to increase. The entry of uncontrolled air into the furnace chamber can be detected on the basis of heat traces in the regenerator and is not allowed or compensated only within narrow limits by matching the combustion air, which can only be reduced by sealing the furnace chamber and increasing the furnace pressure .

In conclusion, for all forms of infiltration air (A) to (D) affecting before the heat accumulator, the cause can usually preferably be identified and eliminated. Automatic compensation by matching the gas volume is the technically appropriate response to all unavoidable infiltration of air. However, it was found that being lower than the minimum furnace pressure itself means reducing the amount of combustion air and increasing the amount of uncontrolled air XF. As long as the determined uncontrollable air volume is not significantly affected by changes in the combustion air volume, the furnace pressure is sufficiently high for stable control. Below this stability limit, it is not possible to reliably reach the target value SP_Lambda by adapting the combustion air volume, but the furnace pressure must be increased accordingly.

Infiltration air into the furnace chamber (cases (E) and (F)) not only causes the largest possible energy loss due to infiltration air, it disturbs the heat balance of the left/right regenerators. However, attempting to compensate for this air infiltration by matching the gas results in increased regenerator temperature and increased thermal imbalance. The technically appropriate answer is no more gas matching, but sealing the furnace chamber and increasing the furnace pressure so that infiltration air is prevented or reduced.

From the above considerations it is evident that a simple _O2 % measurement according to the prior art is not sufficient: only the evaluation of the oxygen balance for the intended combustion and the precise determination of the amount of infiltrated air, together with the evaluation of the thermal trace of this infiltrated air in the regenerator, Only in this way can online cause analysis and selection of technically appropriate control strategies be realized.

According to the invention, compensation of the uncontrollable air XF by adapting the combustion air quantity according to the invention is only permitted in the following cases:

a) Direct entry of uncontrolled air XF into the furnace chamber, which can be detected by a disturbance of the temperature balance of the regenerator and an increase in temperature through the regenerator.

b) Uncontrollable air XF is independent of the amount of combustion air, and in particular not inversely proportional to the amount of combustion air.

Below the stability criteria thus defined, uncontrolled air XF can only be reduced by increasing the furnace pressure.

Above a stability criterion defined in this way, the uncontrollable air can be compensated within wide limits by automatic adaptation of the combustion air quantity in order to maintain the predetermined residual air value SP_Lambda.

Calculation example:

The melt to be melted is fed into the melting furnace 100 and fuel energy is continuously fed to maintain the required temperature E=12 MW. The average oxygen demand of a fuel (eg coke) is assumed to be OMINE = 0.20 Nm3/kWh (fuel energy per cubic meter per kWh). It is known from long-term observations that an uncontrolled infiltration of air with XF=500 Nm3/h occurs continuously for the measured gases. According to system tests, it is also known that when the furnace pressure P in the furnace chamber 10 is higher than 7Pa, continuing to increase the furnace pressure will not cause significant changes in the residual oxygen value in the exhaust gas, that is, the specified furnace pressure threshold is 7Pa. Ensuring complete combustion requires an air surplus of 10%, that is, the air surplus number is Lambda=1.10.

Here, under the assumption of complete combustion, the current remaining air value Lambda and the current oxygen remaining value O2% are related by the following functional relationship:

Lambda=1+1.13×O2%/(20.94%-O2%)

Here, the constant 1.13 was determined from an average fuel analysis according to the measured values of the zirconia-oxygen probes 52 , 52 ′.

Enter a controlled air flow into the melting furnace (Fig. 2 L-ZUF _IST ):

Rated value_air (Figure 2 L-ZUF _SOLL ) = SOLL_Lambda × E × OMINE/0.2094 – XF

＝1.10×12MW×1000kW/MW×0.20Nm3/kWh/0.2094–500Nm3/h

=12.107Nm3/h controlled gas flow

Then, the fuel flow (BS in FIG. 2 ) is always adjusted so that the signal evaluation from the oxygen measurement at the output of the combustion chamber (ie by means of the zirconia-oxygen probes 52, 52') maintains the process value Lambda=1.10 (FIG. 2 λ-AG _IST in ). The corresponding measured value of oxygen in the exhaust gas AG (O ₂ -AG _IST in Fig. 2 ) is:

O2%=20.94%×(Soll_Lambda-1)/(Soll_Lambda-1+1.13)

= 1.70%

If the measured oxygen remaining value is adjusted to be less than 1.70%, that is, the oxygen consumption ΔO2-Verbr _IST according to Fig. 2 is too high, then it is assumed that the lower oxygen remaining value is the higher oxygen consumption ΔO2- In case of the result of Verbr _IST , the fuel flow is reduced accordingly.

If the measured oxygen remaining value is adjusted to be greater than 1.70%, that is, the oxygen consumption ΔO2-Verbr _IST according to Figure 2 is too low, then it is assumed that the higher oxygen remaining value is the lower oxygen consumption ΔO2- In case of the result of Verbr _IST , increase the fuel flow accordingly.

FIG. 2 shows a flow chart of a preferred embodiment of a method for the controlled operation of an industrial boiler 100 with regenerative heating of the furnace chamber 10 according to FIG. relatively constant fuel energy input; here the method 2000 can be executed in the control loop in a relatively short period of a few minutes, that is, at a time period whose duration is significantly lower than that of the combustion cycle, the period of the latter combustion cycle Tens of minutes, such as 20 minutes shown in FIG. 3 .

FIG. 2 shows that, starting from the point of intersection S0 in the first branch I of the control loop, the setpoint value L_ZUF _SOLL for the incoming combustion air is determined in a first step S1 . This can be carried out, for example, according to the calculation example formula given above, wherein in the case of combustion air the setpoint value Lambda _SOLL (SOLL_Lambda above) of the residual air quantity, the required fuel energy E and the fuel-specific minimum average oxygen demand O _MINE and oxygen The ratio with air is 0.2094. In step S2 , the setpoint value L-ZUF _SOLL of the combustion air is corrected using the measured or empirically based infiltration air value XF. Thus, in a third step S3 , the actual value L-LUF _IST of the combustion air is obtained, provided that a suitable control unit is provided.

In the calculation and measurement branch running parallel to the first branch I of the control loop, i.e. the second branch II of the control loop, the actual value LambdaAG _IST of the air residue in the exhaust gas is first determined, for example in the measuring range via Lambda Probes, such as the zirconia-oxygen probes 52, 52' of FIG. 1 . Thus, after step S4, in step S5 the current oxygen residual value O ₂ −AG _IST is determined, for example as O ₂ % _IST according to the last formula in the calculation example, wherein the lambda target value is replaced by the corresponding lambda actual value .

By suitably forming the difference concerning the oxygen value in step S6, the oxygen consumption ΔO ₂ -Verbr _IST can be determined in step S7 from the actual value L_ZUF _IST of the air input and the actual value O ₂ -AG _IST of the remaining oxygen value, as It is converted to burn fuel.

In step S8 , the actual value ΔO _2-IST is compared with the desired value ΔO 2 _- SOLL, as specified in the final formula of the calculation example (1.70% there). If the actual value ΔO _2-IST is higher than the target value ΔO 2 _- SOLL , the fuel quantity BS is increased in step 9 by adapting the compressed air quantity, the raw fuel quantity and/or the fuel mixture, especially for coke. Conversely, if the actual value ΔO _2-IST falls below the target value ΔO 2 _- SOLL , the corresponding fuel quantity is reduced in step 10 . After steps S9 and S10, the control loop can be restarted from the intersection point S0. Conversely, if the actual value and the setpoint value are approximately in the same range, the control loop can be restarted from the point of intersection S0 after, for example, a preset cycle period.

FIG. 3 shows a summary of various process value data in the controlled operation of a regeneratively heated industrial boiler 100 . Here, on the time axis t, a combustion cycle (L or R) of 20 minutes is shown in each case, which results in a period alternately on the one hand with the left heat accumulator associated with at least one fuel injector during the first cycle duration ( L) Combustion air is supplied to the furnace chamber, while exhaust gas is discharged from the furnace chamber separately from the fuel during the second cycle duration (R). For the right regenerator, the cyclical alternating feed is reversed, ie combustion air is fed into the furnace chamber during the cycle duration L and exhaust gas is discharged from the furnace chamber during the cycle duration R. For this purpose, the process values represent the pressure value p _SK in the collecting channel and the oxygen value _OBH in the burner neck.

In this case, the mean value of the thermodynamic value H _U with respect to the fuel and the corresponding minimum air requirement L _MIN-E (proportional to O _MIN-E ) are also shown, although of course in the case of reliable fuels it has a partially strong Instantaneous gradients, and especially none at all for fuels with uncontrollable thermodynamic values, are at any time within the bounds of harmless provisional assumptions based on estimates of fuel composition.

FIG. 3 shows that the oxygen measurement value O ₂ of the zirconia probe is provided for an industrial boiler with regenerative heating in controlled operation, even though the corresponding signal has relatively strong fluctuations. The corresponding residual air value Lambda _IST in the exhaust gas has small fluctuations and points to the desired lambda value Lambda _SOLL within the above-described control range based on the residual air quantity.

Either the Lambda value λ or the oxygen value _O can be used together or alternatively to control the relatively constant fuel energy input of fuels with fluctuating thermal values to the furnace chamber in the manner described above (e.g. according to the calculation example or according to Fig. 2).

FIG. 3 also shows the infiltration air component XF as process value on the one hand (and the corresponding compensating component K _XF , which can be detected essentially as a straight line in the noisy infiltration air component XF ) and the furnace pressure on the other hand. A clear correlation between P. Knowledge about the correlation is advantageous in this approach, since according to a preferred embodiment the oxygen consumption ΔO ₂ -Verbr _IST is used as a measure for the fuel energy used. The oxygen consumption itself proves to be correct again when the infiltration air fraction XF can be compensated and determined relatively reliably independently of the combustion cycle. This is especially the case, as can be seen in area B of FIG. 3 , that the current air ratio (air relative to fuel) Lambda-AG has only a small difference regardless of the combustion cycle L, R, which is related to the air ratio Lambda-AG The course of the process value is different in region A, where it has periodic strong amplitude fluctuations in the combustion cycles L, R.

The reason for the adjustment to the common average amplitude Lambda-AG is to increase the furnace pressure P above a furnace pressure threshold at time T (here the increase is only a few Pa). However, the actual situation is that as the furnace pressure P is increased at the time point T, the furnace pressure threshold exceeds the minimum pressure value, so that the residual oxygen value in the exhaust gas after the furnace chamber is basically the same for the left and right flame sides corresponding to the left and right heat exchangers , especially within the preset upper bandwidth. In other words, the furnace pressure threshold is defined as the lowest pressure value for which the difference in the residual oxygen value between the left and right flame sides corresponding to the left and right heat exchangers cannot continue to be reduced by increasing the furnace pressure, especially at the preset within the lower bandwidth.

Claims (18)

1. the method for the Industrial Boiler (100) that one kind is heated for controlled heat accumulating type of the operation with furnace chamber (10), wherein, control The fuel energy of fuel with fluctuation heating power value to furnace chamber (10) is inputted, and is had steps of：

- by least one fuel injector (20,20 ') to furnace chamber (10) injected fuel, the fuel injector be configured to use In fuel of the injection without combustion air,

- periodically alternately on the one hand input combustion air, and the opposing party to furnace chamber (10) within duration period 1 Face dividually exports waste gas (AG) with fuel within duration second round from furnace chamber (10), wherein,

The input of-regulation combustion air, and determine the remaining oxygen in waste gas,

Characterized in that,

- determine that the oxygen occurred in fuel combustion is consumed according to the combustion air and remaining oxygen of input, and

- identified oxygen is consumed to the measurement for the fuel energy for being used as the used fuel, wherein adjusting for injecting The fuel stream so that oxygen consumption control arrived into predetermined oxygen consumption figures, wherein, take oxygen consumption with fuel energy Predetermined ratio,

- characteristic component of fuel is stored as the operating point with reference thermal force value, and by the composition as heating power value changes Become and proportionally change together, and then matched The fuel stream on the fluctuation of heating power value.

2. in accordance with the method for claim 1, it is characterised in that by matching air supply and/or fuel quantity and/or combustion Material mixes to adjust the The fuel stream for being used to inject.

3. according to the method described in claim 1 or 2, it is characterised in that in the case where heating power value is fluctuated, it is assumed that oxygen is consumed It is proportional between the fuel energy of the fuel.

4. according to the method described in claim 1 or 2, it is characterised in that be preset with specified oxygen consumption, and by matching institute The fuel energy used consumes the consumption control of actual oxygen to specified oxygen.

5. according to the method described in claim 1 or 2, it is characterised in that it is remaining to be preset with specified waste gas air, and by It is under conditions of fuel energy used in The fuel stream matching that the residue control of actual waste gas air is remaining to specified waste gas air.

6. according to the method described in claim 1 or 2, it is characterised in that keep the input of combustion air constant.

7. according to the method described in claim 1 or 2, it is characterised in that automatically adjust the defeated of combustion air by control loop Enter.

8. according to the method described in claim 1 or 2, it is characterised in that the remaining situation of air needed in consideration technology Under the input of combustion air is consistently controlled by control loop, and adjust The fuel stream so that maintain according to default specified Remaining oxygen that waste gas air residue is determined, directly in the waste gas after combustion chamber.

9. according to the method described in claim 1 or 2, it is characterised in that by waste-gas analysis equipment as left storage heater and/or Measuring appliance in right storage heater, measures oxygen content, for directly determining the air remainder of combustion air and/or waste gas (λ), and it regard the air remainder as actual value (λ_IST) the λ controllers of control loop are supplied to, and

Indicate to determine by air is penetrated into：

Whether in the first case in the left storage heater and/or right storage heater of air side or preceding upstream occurs penetrating into air, Or

Whether downstream in a second situation after the left storage heater and/or right storage heater of air side occurs penetrating into air,

In the Part I of the control loop of the first situation for penetrating into air instruction, according to the output of λ controllers, by First adjustment unit, adjusts input of the combustion air to furnace chamber, as adjustable parameter, and

In the Part II of the control loop of the second situation for penetrating into air instruction, according to the output of λ controllers, by Furnace pressure in second adjustment unit, regulation furnace chamber, is used as adjustable parameter.

10. according to the method described in claim 1 or 2, it is characterised in that the furnace pressure in furnace chamber is maintained above into furnace pressure threshold Value.

11. in accordance with the method for claim 10, it is characterised in that the furnace pressure threshold value is defined as minimal pressure force value, right Remaining oxygen value in the minimal pressure force value, the waste gas after furnace chamber is for left and right corresponding with left and right heat exchanger flame Side is substantially the same.

12. in accordance with the method for claim 10, it is characterised in that the furnace pressure threshold value is defined as minimal pressure force value, right In the minimal pressure force value, the difference of the remaining oxygen value between the corresponding left and right fire side of left and right heat exchanger, it is impossible to after It is continuous to be reduced by improving furnace pressure.

13. according to the method described in claim 1 or 2, it is characterised in that automatically control combustion air by PID controller Input, its rated value is that the air of the stoichiometry by fuel quantity, fuel needs and remaining as the default air of target parameter Number (λ_SOLL) product uncontrollable infiltration air input outside Industrial Boiler of lasting determination is subtracted to be formed.

14. according to the method described in claim 1 or 2, it is characterised in that for another temperature controlled control loop In：

- by the furnace chamber temperature as controling parameter, and

- it is used for the first controller of furnace chamber temperature, and

- adjust adjustable with the first of The fuel stream and/or combustion-supporting air flow form by adjustment unit corresponding with the first controller Adjustable parameter.

15. a kind of control device being configured to for performing according to the method any one of claim 1 to 14, with work Industry boiler implosion, it is configured to, by for controlling the fuel energy of the fuel with fluctuation heating power value to furnace chamber (10) to input Method be applied to Industrial Boiler, have：

- computing module, the oxygen that can be occurred by it according to the determination of the combustion air and remaining oxygen of input in fuel combustion Gas is consumed, and

- adjuster, in the adjuster by identified oxygen consumptive use oppose used in the fuel fuel energy Measurement, and the The fuel stream for injection can be adjusted by the adjuster, enabling by oxygen consumption control to pre- The oxygen consumption figures first determined, wherein, the consumption of storage oxygen and the predetermined ratio of fuel energy, and by the characteristic component of fuel The operating point with reference thermal force value is stored as, and the composition is proportionally changed together as heating power value changes, And then The fuel stream is matched on the fluctuation of heating power value.

16. according to the control device described in claim 15, also have：

For the temperature control modules of the first control loop, by it：

- by the furnace chamber temperature as controling parameter, and

- it is used for the first controller of furnace chamber temperature, and

- first with The fuel stream and/or combustion-supporting air flow form can be adjusted by adjustment unit corresponding with the first controller Adjustable adjustable parameter.

17. a kind of Industrial Boiler of the heat accumulating type heating with furnace chamber, also has：

- at least one fuel injector, for furnace chamber injected fuel, it to be configured to inject the combustion without combustion air Material,

- left storage heater corresponding with least one described fuel injector and right storage heater, it is configured to heat accumulating type storage Deposit the heat from waste gas and to combustion air transmit heat, for periodically alternately on the one hand the period 1 continue when It is interior to input combustion air to furnace chamber, and it is on the other hand dividually useless from furnace chamber output with fuel within duration second round Gas, and

- adjustment unit, can be conditioned for inputting combustion air, and can determine by probe and/or empty according to waste gas Gas residue determines remaining oxygen, and

- according to the control device described in claim 15 or 16.

18. according to the Industrial Boiler described in claim 17, its furnace chamber has the melting tank for glass.