ES2265927T3 - A COMBUSTIBLE SOLID MATERIAL INCINERATION PROCESS. - Google Patents

Abstract

This invention relates to a method for incinerating solid combustible material in an incineration zone in an incineration reactor. The method of this invention comprises the steps of adjusting at least one of the charging to or the feeding of the combustible material through the incineration zone so as to maintain the amount of material in the incineration zone substantially constant, comprising the steps of (1) measuring an over-all gas pressure P<i> in the incineration zone, (2) measuring a primary gas pressure below the carrier for the combustible material P<g>, (3) determining DELTA P<r> = P<i> - P<g> (4) determining DELTA P<ro> which is the pressure difference over the carrier that corresponds to the optimum amount of material in the incineration zone, (5) calculating the difference DELTA P between DELTA P<ro> and DELTA P<r>, (6) minimising DELTA P by adjusting the speed of the charging or the feeding of the combustible material to or through the incineration zone.

Description

A solid material incineration process fuel.

The present invention relates to a process of incineration of combustible solid material, specifically waste solid fuels, as described in the preamble of the first claim. In the following description, the term waste is refers to solid fuel material in general as well as material solid residual concrete.

In general, it is very desirable for several reasons an incineration process in which combustion can be controlled of solid fuel material permanently. First, stable combustion makes it easy to meet the emission standards that orders the law for exhaust gases, coal and ashes. In addition, limiting temperature variations in the incinerator, the energy costs of maintenance of the optimal combustion conditions. Finally, limiting the temperature variations in the incinerator can also minimize variations in thermal and mechanical loads at that the incinerator is subjected, which in turn will lead to longer duration of the incinerator, specifically the feed and combustion grill.

However, the operation of an incinerator of waste can be complicated by the variations that occur in, among others, the size and density of the waste that is they supply mostly in the form of packages more or less dense, and by the variations in the composition of the waste, by example its water content, which will lead to variations in the calorific value of waste. Variations in these parameters can greatly complicate the process and its system of control, in particular if the control system has as target an output of constant steam production, in which a steam controller controls the combustion rate of waste.

In a first known system that has as target a constant production of steam, the steam controller controls the amount of primary combustion air that is supplies the incinerator, based on the steam outlet. The air Primary combustion is responsible for process maintenance of combustion However, this type of system behaves with often the problem of an overloaded grill system of combustion and ashes that have not been completely burned. Specifically, when the steam output decreases, it is supplied primary combustion air additional to the incinerator. This entails often more temperature reduction of the chamber of combustion instead of an increase in it. The cooling of the combustion chamber occurs especially in case the air primary is not able to penetrate waste, for example because the waste is too dense, or a large pile of wet waste When the combustion rate decreases and does not As the primary air supply increases, the oven cools. Simultaneously, the concentration of oxygen in the gases of combustion.

In a second known system that has as target a constant steam output, the latter is controlled controlling the amount of waste that is supplied to the incinerator. To do this, the grill speed varies Supplies the waste in the oven. This system often assumes the problem of involving a combustion grill system overloaded, especially if the waste is more very dense and that the primary air can barely penetrate the waste. As a result, the waste may not burn completely, even when a large amount of air is supplied primary.

In the document US-A-5,398,623 a solution to the problem of the variable operation of an incinerator of waste In the procedure described in the document US-A-5,398,623 is attempted stabilize the operation of the waste incinerator keeping the amount of waste in the grill system of approximately constant combustion, regardless of value calorific or density of waste. This is done by varying the speed of the combustion grill system, that is the speed with which waste moves through the incinerator. The amount of waste present in the grill system of combustion is determined by regulating the resistance exerted on the hydraulic drive mechanism that drives the system combustion grill This resistance is measured as the pressure hydraulic in the hydraulic drive mechanism.

The procedure described in the document US-A-5,398,623 has the drawback that the system with which it regulates and controls the amount of combustion grill system waste is one and the same system, that is the hydraulic drive mechanism which drives the combustion grill system. The speed of combustion grill system is controlled by adjusting the flow rate of hydraulic fluid flow in the drive mechanism hydraulic. However, varying the flow rate of the liquid hydraulic to vary the speed of the grill system of combustion, the hydraulic pressure itself varies in the system of actuation and the measured hydraulic pressure no longer corresponds to the amount of waste present in the grill system of combustion. As a consequence, the procedure cannot be used described in the document US-A-5,398,623 to control the amount of waste in the combustion grill system, not be that the hydraulic system is not controlled, that is the hydraulic drive mechanism does not control the speed of the combustion grill system.

The document EP-A-0955499 describes a incineration procedure of combustible solid material in a incineration reactor according to the preamble of claim 1 in which adjusts the flow rate of primary air to areas of combustion of the incinerator according to the measuring devices located in the combustion zones. In Patent Abstracts of Japan, vol. 008, No. 258 (M-340) with respect to the document JP 59129316A, describes a process for drying dust in which controls a powder feeder in response to detected values pressure below the drying racks and the volume of air that It must be provided under the drying racks. Neither the devices or the procedures described get reliable measurement readings due to dirt and readings inaccurate by the sensors. Consequently, combustion or drying are not effective.

So, you need to find a procedure with which the amount of waste can be determined and controlled that is supplied to the incinerator, regardless of the system hydraulic responsible for the displacements of the system combustion grill

The objective of the present invention is provide a procedure that can be determined in a way reliable amount of waste that is supplied to the incinerator and The incinerator can operate stably.

This is achieved with the present invention with the attributes of the characteristics part of the first claim.

According to the procedure of this invention,

1) First, ΔP ro is determined. ΔP ro is the optimum gas pressure difference over the bed of waste in the conveyor, which corresponds to a process of optimal incineration and that is representative of the optimal amount of waste from the conveyor. As conveyor waste they constitute a resistance that hinders the passage of primary air of combustion from a position under the conveyor to the area of incineration above the conveyor, ΔP ro is representative of the optimal amount of waste in the conveyor

2) the actual pressure of the gas P i in the incinerator in a position above the conveyor

3) the actual pressure of the gas P g of the primary combustion air at the inlet position of the incinerator, under the conveyor that transports the waste

4) the difference ΔP r = is calculated P g - P i. The difference ΔP r is proportional to the resistance detected by the gas, when it flows from the inlet of primary air through waste to the area of incineration and provides an indication of the amount of waste of the conveyor

5) ΔP r - ΔP ro is calculated = ΔP. ΔPro corresponds to the pressure difference on the conveyor that corresponds to a combustion process optimum. ΔP is the difference between a real difference of pressure on the conveyor and the optimum pressure difference in the conveyor

6) at least one of the speeds of loading of the combustible material into the incineration zone or the feeding of the combustible material through the zone of incineration to minimize ΔP.

Perform the subtraction ΔP r = P g - P i is, in fact, a first correction that minimizes the influence of non-process parameters on air pressure primary under the conveyor. Through this first correction the influence of non-process parameters in the adjustment of at least one of the material loading speeds fuel to the incineration or feed area of the combustible material through the incineration zone.

With this first correction in particular you can minimize the influence of a variable pressure in the area of incineration. These pressure variations may be due, for example, to the variable production of flue gas in the incinerator, especially with sudden changes in properties physical or thermal value of waste. By correction described above it is possible to prevent the feed or waste transport speed suits constantly to pressure fluctuations that have nothing to do with the amount of waste from the transporter itself.

In the process of this invention, the Waste conveyor speed is controlled by adjusting the hydraulic pressure of the mechanism that drives the conveyor. By On the other hand, the amount of waste present in the conveyor is determined by measuring the difference in gas pressure on the incinerator conveyor In this way the drive of the transporter decouples from measuring the amount of waste of the conveyor, so that interference from both phenomena and a reliable measurement of the amount of waste from the conveyor.

This decoupling of both mechanisms implies the advantage that the conveyor can be operated so continuous and can operate at variable speeds, and allows with a reliable measurement of the amount of waste of the conveyor.

In addition, with the process of this invention The speed of the grill can be monitored continuously. He conveyor movement can be specifically described as a slow, alternating and repeated sliding back and forth from approximately continuous way, to advance the waste by the conveyor As the conveyor can be operated by a approximately continuous way, no need to provide times dead between sliding from side to side of the conveyor and you can maintain the speed at which the rather low conveyor. This way you can not only get more constant steam production but also dust production can be reduced and changes can be avoided abrupt in the emission of pollutants in flue gases, thus leading to a more stable operation of a plant of flue gas treatment provided after incineration.

As a conveyor, a combustion grill system, but others can be used Conveyors generally known in the art.

According to the invention, ΔP is divided by square of the volumetric primary air flow rate v2po (m 3 / s) through the conveyor, when a difference of pressure on a duct, i.c. a grill element of combustion, is always proportional to the square of the flow through of this duct. With this correction you can minimize the influence of a variable primary combustion air flow rate on ΔP, and so on the speed of the grill system of combustion.

In addition, to allow optimal control of the incineration of waste throughout the incinerator and for ensure that the incineration process is carried out so complete as possible, the incineration zone is divided into a plurality of individual combustion zones, air being supplied primary combustion to each individual zone, adjusting the flow rate from primary combustion air supply to each supply individual air or incineration zone. To do this, the actual gas pressure P g in each inlet device of primary combustion air and the actual pressure P l z above of the conveyor in each individual zone of incineration z and calculates ΔP r z for each zone. However, put that the pressure differences between the individual zones of incineration on top of the conveyor of waste is in its mostly small, the values of P i z can approach reasonable accuracy through a single measurement of P i in the incinerator. Preferably it can also be measured and adjust the flow rate v_ {pa} for each zone.

Primary combustion air is supplied to the incinerator through an air supply device primary combustion The air supply device primary combustion comprises an input through which supplies primary combustion air to the supply device of primary combustion air and an outlet through which it is supplied primary combustion air from the supply device primary combustion air to an incineration zone of the incinerator. The flow rate of the primary air flow of combustion in each individual zone determining

- the pressure of the primary combustion air in the inlet and outlet of the air supply device primary combustion,

- determining the pressure difference between the entry and exit,

- calculating the corresponding flow rate at the pressure difference measured.

With known techniques, measurements of primary combustion air flow per combustion zone with frequency are not reliable when the air supply tubes are too short to accommodate the required instruments and when the instruments applied deviate frequently because they get dirty with the dust present in the air flow. The inventor has now solved these problems by determining the air flow Primary as follows:

- the primary air pressure of combustion in the inlet and outlet of the supply device of air. The pressure difference between the inlet and the exit,

- each air supply device has a characteristic curve from which the flow rate corresponding to the pressure difference between the inlet and outlet of primary air supply device of combustion

As an air supply device they can used devices that are generally known in the technique, for example a fan or a supply valve air. If a fan is used, if desired, the calculation can be corrected according to the speed variations of Rotation of this fan. It is also possible to determine the flow rate of primary combustion air flow per combustion zone when primary air is supplied by the existing technique of a single fan, from which the primary air of combustion towards the individual incineration zones through gas control valves, for example butterfly valves or registry. In this case, the pressure difference of the control valve, and a calculation is made according to the curve characteristic of the control valve instead of the curve fan feature

In a second preferred embodiment of this invention, ΔP / v 2 pa is calculated at intervals of predetermined time and the average is calculated as a function of weather. This is preferably done by determining and calculating the average of ΔP r continuously, specifically measuring P g and P i and calculating the difference ΔP r = P g - P i continuously. This way you can avoid that the speed of feeding or transport of waste is unstable adjustment due to rapid variations of pressure that are not important for the combustion process. From in this way a filtering of the noise in the pressure difference signal. An example of pressure variations that are not important for the incineration process itself it is, in case the conveyor comprises a plurality of rear grill elements, the fall of a quantity of waste from one element to the next element.

The present invention also relates to a device for incinerating combustible solid material, the device comprising an incineration reactor with at least an incineration zone to burn the combustible material, a conveyor to transport the combustible material and provide the combustible material through at least one area of incineration, a device for supplying combustion air under the conveyor and means to adjust the amount of combustible material in the incineration zone.

An embodiment of the present invention is a device for incinerating solid material fuel in an incineration zone in a reactor incineration so that there is an optimal amount of material in the incineration zone, which includes:

- an incineration reactor with at least one incineration zone to burn the combustible material,

- a conveyor to transport the material fuel and provide the combustible material through at minus an incineration zone,

- a means to supply combustion air under the conveyor and

- means to adjust the amount of material fuel in the incineration zone, so the means to adjust the amount of combustible material in the area of Incineration comprises means for:

- measure a global gas pressure P i of the incineration zone,

- measure a primary gas pressure below conveyor for the combustible material P g,

- determine a pressure difference on the transporter ΔP r = P i - P g,

- determine ΔP ro which is the pressure difference on the conveyor that corresponds to the optimal amount of material in the incineration zone,

- calculate the difference ΔP between ΔP ro and ΔP r,

- minimize ΔP by adjusting at least one of the loading rates of the combustible material to the area of incineration or feeding of combustible material through the incineration zone, characterized in that

- each incineration zone is divided into one plurality of individual combustion zones, comprising the device separate air supply devices for supply primary air to each individual combustion zone and that comprises means for adjusting the primary air that is supplied to each individual combustion zone,

- the device comprises a means to adjust the speed of said feed or charge of the combustible material according to ΔP / v 2 pa in which v_ {pa} is the flow rate of primary combustion air flow, and

- the device comprises means for measuring the flow rate of primary combustion air in each zone individual, which includes:

- means for determining an air pressure primary combustion in an inlet through which supplies primary combustion air to the supply device primary combustion air,

- means for determining an air pressure primary combustion at an outlet of the supply device of primary combustion air through which air is supplied primary combustion to the incinerator,

- means to determine the difference of pressure between the inlet and outlet of the supply device primary combustion air,

- means to calculate the flow rate corresponding to the pressure difference between the inlet and the output of the primary air supply device of combustion.

The present invention also relates to a device as described above, in which the transporter of the combustible material comprises a plurality of individual grill elements to advance the material fuel through the incineration zone, with a air supply device under each element of grill.

The present invention also relates to a device as described above, in which the transporter of the combustible material comprises a plurality of first individual combustion grill elements, being mounted the first grill elements slidably in forward and backward direction to transport waste from a previous combustion zone to a next zone of combustion.

The present invention also relates to a device as described above, in which the system of combustion grill comprises a plurality of seconds grill elements, alternating the first grill elements with the second grill elements, being mounted the second grill elements so that they can flip to Increase combustion intensity.

The present invention also relates to a device as described above, in which the system of combustion grill comprises between the second element of grill and a first rear grill element, a third grill element, the third grill element being mounted in a fixed way.

The present invention also relates to a device as described above, in which the first and second grill elements can be controlled individually.

The present invention also relates to a device as described above, in which the device comprises means for controlling the speed of the first and second grill elements continuously.

The conveyor of combustible material preferably comprises a plurality of individual elements grill to advance the combustible material through the incineration zone, being provided with a device primary combustion air supply under each element of grill, to allow increased process control incineration. The most commonly used technique at this time to supplying primary combustion air to the incinerator uses a single fan The distribution is controlled from the fan of primary combustion air over and along the different combustion grill elements using butterfly valves or registry. Splitting the incineration zone into a series of zones individual and controlling the primary air supply of combustion in each individual zone, an increase of incineration process control.

The combustible material preferably advances to through the incineration zone using a conveyor that it comprises a plurality of rear conveyor elements, some of which are slidably mounted on direction back and forth to transport waste from a combustion zone prior to a next combustion zone. Conveyor elements are preferably used individual combustion grill elements. Each element of conveyor preferably comprises a first element of combustion grill that is slidably mounted on forward and backward direction to transport waste from a previous combustion zone to a next zone of combustion. Among the first combustion grill elements later, at least a second element is preferably mounted of combustion grill, the second elements being mounted of combustion grill so that they can flip, preferably above a predetermined angle to Increase combustion intensity. Next to a second combustion grill element, that is between a second combustion grill element and the next first element of combustion grill, preferably a third is provided fixed combustion grill element. Preferably the first and second combustion elements can be controlled individually and separately.

The device also preferably comprises a burn control device to ensure that the material solid fuel has been completely burned before removing it from incinerator.

The invention is best explained in the figures. attached and in the description of the figures.

Figure 1 shows a cross section to through a reactor for waste incineration.

Figure 2 shows a detail of a system of combustion grill for use in the procedure of this invention.

The incinerator shown in figure 1 comprises overhead cranes to transport solid combustible material, eg waste 1 to a reactor feed hopper and a loading ramp 3. The ramp actually works as a closure airtight to the top of the incinerator, but also is provided to distribute waste 1 to a device of waste supply 4 with which the waste is supplied to a conveyor 5 to transport the combustible material to through the burning area where it burns. He conveyor 5 can be any known conveyor for those skilled in the art, but preferably comprises a combustion grill system 5. The grill system of Combustion is also provided to dry, ignite and burn the combustible material in the gasification and combustion zone. For reinforce combustion, primary combustion air is supplied to the incinerator through an air supply device primary combustion 9, which is preferably located below of the combustion grill system. The delivery device of primary combustion air 9 may comprise for example a fan or an air supply valve or any other primary combustion air supply device known in The technique. The device also preferably comprises a burning control device to ensure that the material solid fuel burns completely before leaving incinerator.

As can be seen in Figure 2, the system of combustion grill 5 that is used in the incinerator of this invention preferably comprises a plurality of elements of combustion grill (11-16), increasing the degree of combustion of combustible material from a grill element of previous combustion to a combustion grill element later. The combustion grill elements 11-16 also function as means to transport the combustible material 1 from the feed hopper 3 to a previous, to a combustion grill element next, and by last to an ash discharge 6.

In a preferred embodiment, provides an air supply device under each 11-16 grill element to provide a increased control of the combustion process. As a device air supply is preferably used a valve or a fan, but you can also use other devices air supply known in the art. Each device of air supply comprises an inlet through which supplies primary combustion air and an outlet through the that the primary combustion air leaves the device air supply to the incinerator. Means are provided for determine the air flow rate at the device outlet of primary air supply. This can be done by measuring really the pressure at the inlet and outlet of the device primary combustion air supply and determining the flow corresponding from the characteristic curve of the device of air supply.

The combustion grill system 5 comprises preferably a plurality of individual elements of grill, preferably a plurality of sliding stands later, 11-16, with which the layer moves of the combustible material on the combustion grill. He sliding movement of the stands is preferably a movement slow and continuous, to avoid generating dust in the incinerator and increase the duration of the incinerator. Also, when the bleachers 11-16 move continuously, can ensure virtually continuous steam production and in consequently, a production of electricity practically keep going. The sliding steps 11-16 determine the thickness of the layer of combustible material, residence time of the combustible material in each combustion zone and the quality of combustion.

In addition, the combustion grill system 5 preferably comprises a plurality of turning stands (17-20), which untangle and ventilate the waste. This is important for drying and ignition of waste, to activate combustion when necessary and to obtain a full burning of ashes. This combination of horizontal action performance and vertical ventilation action (flipping) allows the incinerator suits short and long term fluctuations in the waste composition. That way, it can be controlled preferably performance (slippage) and ventilation (flipping) of each individual zone (grill element of combustion). In addition, independent control of the two movements, that is to say sliding and turning. Naturally, the flip action stops automatically because of the increased risk of dust production when you are untangling and no more intense ventilation of the waste.

During the combustion of waste, it they generate flue gases, which are mostly removed from the incinerator using a fan 17. A reactor that incinerates waste is frequently coupled to a waste boiler in which converts the thermal energy obtained in the gases of steam combustion In turn, this steam can be used for purposes of electricity production, air preheating of combustion, industrial processes, hot water supply, etc.

In the process of this invention, first the optimal amount of combustible material to be determined is determined be present in the incineration zone. Material is provided solid fuel to the incineration reactor and transported to and through the incineration zone at a transport speed by the conveyor. The amount of combustible material in the incineration zone corresponds to

- measure a global gas pressure P i of the incineration zone,

- measure a primary gas pressure below conveyor of combustible material P g,

- determine a pressure difference on the transporter ΔP r = P i - P g,

- determine ΔP ro which is the pressure difference on the conveyor that corresponds to the optimal amount of material in the incineration zone,

- calculate the difference ΔP between ΔP ro and ΔP °.

To improve the incineration process, adjust the speed of loading the combustible material to the area of incineration or feeding of combustible material through from the incineration zone to minimize ΔP. The speed of the fuel material feed conforms to ΔP / v 2 pa, in which v_ {pa} is the flow rate of the primary combustion air. ΔP / v 2 pa is measured at predetermined time intervals and the average is calculated as a time function or ΔP / v2pa is filtered.

The primary air flow rate is measured in each individual combustion zone determining an air pressure primary at the input and output of the supply device of air, determining the pressure difference between the inlet and the output, calculating the flow rate corresponding to the pressure difference measured.

Claims (9)

1. A procedure to incinerate material solid fuel in an incineration zone in a reactor incineration, this procedure comprising the stages of determine an optimal amount of material that must be present in the incineration zone, provide combustible material to the incineration reactor, transport the combustible material to and through the incineration zone at a transport speed by means of a conveyor for this, supply primary air of combustion to the incineration zone with a flow rate, to through an air inlet located under the conveyor, incinerate the combustible material in the incineration reactor to produce ashes and exhaust gases, determine the amount of combustible material in the incineration zone, adjust the quantity of combustible material in the incineration zone adjusting to minus one of the charges or the feed of combustible material to through the incineration zone to maintain the amount of material in the substantially constant incineration zone, by what the adjustment of the amount of combustible material in the area Incineration comprises the stages of - measure a global gas pressure P i of the incineration zone, - measure a primary gas pressure below conveyor of combustible material P g, - determine a pressure difference on the transporter ΔP r = P i - P g, - determine ΔP ro which is the pressure difference on the conveyor that corresponds to the optimal amount of material in the incineration zone, - calculate the difference ΔP between ΔP ro and ΔP r, - minimize ΔP by adjusting at least one of the loading speeds of the combustible material to the area of incineration or feeding of combustible material through the incineration zone, characterized because - the incineration zone is divided into one plurality of individual combustion zones, air being supplied primary to each individual combustion zone through a separate air supply device and adjusting to each zone individual combustion, - adjust the speed of said feed or loading of the combustible material according to ΔP / v 2 pa in the that v_ {pa} is the flow rate of the primary combustion air, Y - the flow rate of the primary air is measured of combustion in each individual zone - determining a primary air pressure of combustion in an inlet through which air is supplied primary combustion to the primary air supply device of combustion, - determining a primary air pressure of combustion at an outlet of the air supply device primary combustion through which primary air is supplied of combustion to the incinerator, - determining the pressure difference between the inlet and outlet of primary air supply device of combustion, - calculating the corresponding flow rate to the pressure difference between the inlet and outlet of the primary combustion air supply device. 2. A method according to claim 1, in which ΔP / v 2 pa is measured at time intervals default and the average is calculated as a function of time or ΔP / v2pa is filtered. 3. A device for incinerating material solid fuel in an incineration zone of a reactor incineration so that there is an optimal amount of material in the incineration zone, which includes: - an incineration reactor with at least one incineration zone to burn the combustible material, - a conveyor to transport the material fuel and provide the combustible material through at minus an incineration zone, - means for supplying combustion air under the conveyor and - means to adjust the amount of material fuel in the incineration zone, so the means to adjust the amount of combustible material in the area of Incineration comprises means for: - measure a global gas pressure P i of the incineration zone, - measure a primary gas pressure below conveyor for the combustible material P g, - determine a pressure difference on the transporter ΔP r = P i - P g, - determine ΔP ro which is the pressure difference on the conveyor that corresponds to the optimal amount of material in the incineration zone, - calculate the difference ΔP between ΔP ro and ΔP r, - minimize ΔP by adjusting at least one of the speeds of the loading of the combustible material to the incineration zone or of the feeding of the combustible material through the incineration zone, characterized in that - each incineration zone is divided into one plurality of individual combustion zones, comprising the device separate air supply devices for supply primary air to each individual combustion zone and that comprises means for adjusting the primary air that is supplied to each individual combustion zone, - the device comprises means to adjust the speed of said feed or charge of the combustible material according to ΔP / v 2 pa in which v_ {pa} is the flow rate of primary combustion air flow, and - the device comprises means for measuring the flow rate of primary combustion air in each zone individual, which includes: - means for determining an air pressure primary combustion in an inlet through which supplies primary combustion air to the supply device primary combustion air, - means for determining an air pressure primary combustion at an outlet of the supply device of primary combustion air through which air is supplied primary combustion to the incinerator, - means to determine the difference of pressure between the inlet and outlet of the supply device primary combustion air, - means to calculate the flow rate corresponding to the pressure difference between the inlet and the output of the primary air supply device of combustion. 4. A device according to claim 3, wherein the carrier of the combustible material comprises a plurality of individual grill elements to advance the combustible material through the incineration zone, being provided with an air supply device under each grill element. 5. A device according to claims 3 or 4, in which the conveyor of the combustible material comprises a plurality of first individual grill elements of combustion, the first grill elements being mounted sliding form in forward and backward direction to transport waste from a previous combustion zone to a Next combustion zone. 6. A device according to claim 5, in which the combustion grill system comprises a plurality of second grill elements, alternating the first grill elements with the second elements of grill, the second grill elements being mounted way they can flip to increase the intensity of the combustion. 7. A device according to claim 6, in which the combustion grill system comprises between the second grill element and a first grill element rear, a third grill element, the third being mounted fixed grill element. 8. A device according to claim 7, in which the first and second grill elements can be individually control 9. A device according to claim 8, in which the device comprises means to control the speed of the first and second grill elements so keep going.