Prefabricated composite blowing grate plate module, blowing conveying base plate, and grate-type pre-combustion furnace

Abstract

A prefabricated composite blowing grate plate module (10), a blowing conveying base plate (30), and a grate-type pre-combustion furnace. The blowing grate plate module (10) consists of a housing (101), a wear-resistant castable material (102), and at least two gas flow nozzles (103) with upwardly inclined outlets, wherein ejection openings of the gas flow nozzles (103) are all located on a material receiving surface of the blowing grate plate module (10), and the material receiving surface is the upper surface of the blowing grate plate module (10); and in a material flow direction, the included angle γ1 between the ejection direction of the ejection opening of the gas flow nozzle (103) located on the rearmost side and the material receiving surface of the blowing grate plate module (10) is 10°-35°, and the included angle between the ejection direction of the ejection opening of each of the remaining gas flow nozzles (103) and the material receiving surface of the blowing grate plate module (10) is equal to γ1 or gradually decreases, such that a gas flow entering the gas flow nozzles (103) is obliquely ejected upwards along the material receiving surface, thus driving materials to be ejected upwards and form a parabolic path so as to rise and move forwards. The device can reduce the problems of incomplete combustion, operating-situation fluctuation, skinning and blockages, NOx exceeding the standard, etc., caused by using fossil fuels in a firing system, and can achieve the aims of increasing the proportion of alternative fuel usage, stabilizing a thermal regime of a kiln, and enabling ultra-low emissions of the system.

Description

Prefabricated composite injection grate module, injection conveying bottom plate and grate precombustion furnace TECHNICAL FIELD

[0001] The present application belongs to the technical field of industrial production, and particularly relates to a prefabricated composite injection grate module, an injection conveying bottom plate and a grate precombustion furnace for disposing low-grade solid waste fuel. BACKGROUND

[0002] Co-processing of solid waste in kiln has become one of the trends of current industrial green development. Low-calorific-value solid waste, such as biomass, waste spinning, RDF (waste-derived fuel), etc., has a high water content and a large two-dimensional size, and generally needs to increase a pre-processing device to reduce the negative impact on the original system and play the role of carrying the calorific value of solid waste to reduce fossil fuels. Typical pre-processing devices, such as hot disc furnaces, rotary kilns and ladder-type pre-combustion furnaces, can be used for fuel replacement in kiln systems, and the ladder-type pre-combustion furnace as a non-moving part has become one of the pre-combustion devices with broad application prospects.

[0003] Chinese Patent No. CN207661818U discloses an aerodynamic conveying bottom plate for a ladder-type combustion chamber, which has a plurality of steps containing nozzles and covering elements made of refractory material and is mounted by specific fastening elements; wherein the nozzles in the steps are oriented horizontally or downwardly inclined in the direction of the gas flow. In this patent, the ejected gas flows horizontally upward or downwardly inclined, which has a good forward transmission effect for material conveying and can also prevent the injection port from being blocked. However, the device has a greater pushing and transmission effect on the material than rolling and stirring, and has limited effect on improving the full contact of the material with oxygen-containing high-temperature air, and the cold air close to the high-temperature material receiving surface greatly shortens the service life of the refractory material.

[0004] Chinese Patent No. CN218566182U discloses a ladder gas tank and a pre-combustion furnace having the same, which contains an upper panel and a front panel with a front gas outlet; the inside of the shell is provided with a gas injection cooling pipeline and a gas injection pipeline. This patent has a good protection effect on the combustion upper platform through the cooling gas flow of the upper panel, solving the problem of easy damage to the ladder platform. However, the forward transmission effect of the material is limited, and the mixing and disturbance between the material and the gas are not solved. In addition, the above patent does not mention how to adopt an intelligent control strategy for different working conditions to match the conveying process of the replacement fuel and the drying and combustion process.

[0005] In summary, the main problems of the current ladder-type pre-combustion furnace are:

[0006] 1) The material reaction inside the furnace is uneven, and the local sticky and wet waste is severely agglomerated, which cannot fully contact with the oxygen-containing high-temperature air, resulting in a low waste combustion rate, large fluctuations in CO at the decomposition furnace outlet, and uncontrollable NOx emissions, making it impossible to achieve a large proportion of waste disposal.

[0007] 2) The high-temperature receiving surface is prone to cracking when blown by high-speed cold air; a large amount of liquid phase is produced during combustion, which adheres to the bottom plate and near the nozzle, easily causing blockage and crusting.

[0008] 3) The conveying process of alternative fuels and the drying and combustion process are not matched. When the quality of the waste being treated changes or the feed rate fluctuates, the corresponding adjustments cannot be made in a timely manner. There is a lack of reasonable and intelligent monitoring methods and control strategies to avoid affecting the combustion conditions inside the kiln.

[0009] Summary of the Invention

[0010] To address the technical problems existing in the prior art, this invention provides a prefabricated composite spray grate module, a spray conveying base plate, and a grate-type pre-combustion furnace. Through the structural design of the prefabricated spray grate module, the gradient material distribution design of the spray conveying base plate, and the intelligent control mode, it can reduce problems such as incomplete combustion, operating condition fluctuations, crusting and blockage, and NOx exceeding standards caused by the use of fossil fuels in the firing system. This achieves the goals of increasing the proportion of low-grade solid waste used as alternative fuel, stabilizing the kiln thermal regime, and achieving ultra-low system emissions.

[0011] This invention is implemented as follows: a prefabricated composite blown grate module consists of a shell, wear-resistant castable filled within the shell, and at least two upward-sloping airflow nozzles embedded within the wear-resistant castable. The nozzles are all located on the receiving surface of the blown grate module, which is its upper surface. Along the material flow direction, the angle γ1 between the nozzle at the rearmost side and the receiving surface of the blown grate module is 10–35°. The angles between the nozzles of the remaining airflow nozzles and the receiving surface of the blown grate module are equal to or gradually decrease from γ1. This causes the airflow entering the nozzles to be sprayed upwards along the receiving surface of the blown grate module, causing the material to be sprayed upwards in a parabolic path, increasing the contact time with the high-temperature air.

[0012] Preferably, the housing and the airflow nozzle are both made of heat-resistant steel with a temperature resistance of 1000-1300℃.

[0013] Preferably, the receiving surface of the blown grate module is covered with a high-temperature resistant SiC plate.

[0014] Preferably, the airflow nozzle gradually narrows from the inlet to the outlet in the transverse direction, and the instantaneous velocity released after the airflow is blown by the airflow nozzle is supersonic.

[0015] Preferably, each gas flow nozzle in each said injection grate module uses the same inlet for gas supply, and the gas flow supplied by the injection grate module is high-pressure combustion-supporting air or fuel gas.

[0016] An injection conveying bottom plate is composed of injection grate modules arranged in multiple levels in the longitudinal direction and multiple columns in the transverse direction and placed obliquely, and discharge grate modules at the end of the injection conveying bottom plate, the injection conveying bottom plate is arranged obliquely downward along the material flow direction, and is divided into three zones along the material flow direction, namely a preheating section, a combustion section, and a discharge section, different combinations of grate modules are arranged in the preheating section, the combustion section, and the discharge section respectively to form an injection conveying bottom plate with gradient distribution of materials, and to realize upward rolling of the bottom materials and forward conveying of the alternative fuel on the injection conveying bottom plate.

[0017] Preferably, the injection grate modules are arranged obliquely downward along the material flow direction, and the oblique angle α is 2-10°; the nozzles of the gas flow nozzles located at the last side along the material flow direction between two adjacent injection grate modules are located at the overlapping junction of the upper and lower injection grate modules.

[0018] Preferably, the length of the material receiving surface of a single injection grate module in the preheating section is greater than the length of the material receiving surface of a single injection grate module in the combustion section, 1-3 injection grate modules are arranged in the preheating section, and the preheating section angle β1 is 15-28°; 2-6 injection grate modules are arranged in the combustion section, and the combustion section angle β2 is 28-35°; 1-2 discharge grate modules are arranged in the discharge section, and the discharge section angle β3 is 45-60°; and β1<β2<β3.

[0019] A grate pre-combustion furnace for processing alternative fuel includes a combustion chamber and an injection conveying bottom plate, the injection conveying bottom plate is located at the bottom of the combustion chamber, the discharge grate module of the injection conveying bottom plate extends into the combustion furnace, the combustion chamber is provided with an alternative fuel inlet, a high-temperature air inlet, and a sand inlet, the alternative fuel inlet and the high-temperature air inlet are arranged at one end of the combustion chamber, the high-temperature air inlet is connected to a high-temperature air inlet pipe, the other end of the combustion chamber is connected to the combustion furnace, and the sand inlet is located at the dome of the combustion chamber and / or the high-temperature air inlet.

[0020] Preferably, the sand is a calcium-based mineral material.

[0021] Preferably, the top of the combustion chamber is provided with multiple temperature measuring points for monitoring temperature distribution and high-temperature cameras for monitoring the combustion state, and the outlet of the combustion chamber is provided with gas composition measuring points for monitoring the composition of the outlet gas.

[0022] Preferably, the alternative fuel inlet is located at and / or below the high-temperature air inlet; when located at the high-temperature air inlet, a material distribution box is arranged at the alternative fuel inlet, and the alternative fuel is distributed into the high-temperature air inlet pipe by the material distribution box and fed into the combustion chamber together with the high-temperature air; when located below the high-temperature air inlet, an alternative fuel feeding device is arranged at the alternative fuel inlet, and the alternative fuel is fed into the combustion chamber by the alternative fuel feeding device.

[0023] Preferably, the blowing operation mode of the blowing conveying bottom plate is set according to the principle of traversing all columns in small cycles, the adjacent two times of blowing of different stages of blowing grate modules are at least separated by 1 stage, the order of blowing of each stage is sequentially blowing from the low-temperature zone to the high-temperature zone according to the dome temperature monitoring data, and the non-adjacent blowing of the same stage of blowing grate modules is adopted so that the material cannot enter the grate gap formed by the nozzles of the adjacent column of blowing grate modules, and finally all the blowing grate modules are traversed.

[0024] The working frequency of the blowing grate module is calculated according to the multi-point temperature average value measured by the multiple temperature measuring points at the top of the combustion chamber, and the formula is as follows:

[0025] Wherein, T avg is the multi-point temperature average value, unit: °; τ iintel is the interval time of each adjacent two times of blowing, unit: s.

[0026] The present application fully considers the disadvantages of the existing equipment in use, optimizes the structure of the prefabricated blowing grate module, the design of the gradient gradual distribution of the blowing conveying bottom plate and the blowing mode, uses high-speed gas to blow and uplift the material, makes the material present a parabolic path, increases the contact time of the waste and the high-temperature air flow, strengthens the drying, cracking and combustion speed of the waste, speeds up the process of effective utilization of the waste, protects the air blowing outlet by using the prefabricated structure of the blowing grate module itself, avoids the phenomenon of skinning and clogging and material leakage, reduces the peeling phenomenon of the refractory material near the blowing outlet caused by thermal shock, prolongs the service life of the refractory material, and improves the effective operation rate of the pre-combustion furnace.

[0027] The present application solves the problems of local insufficient ventilation and reaction process regulation in the pre-combustion furnace, fully utilizes the high-temperature air of the firing system for pre-combustion, returns the heat released by the reaction of the alternative fuel to the firing system, reduces the burden of the firing system for directly processing large-scale solid waste, realizes the harmless disposal of large-scale solid waste and the energy substitution of fossil fuels, and achieves the purpose of energy saving and carbon reduction.

[0028] The present application has the advantages and positive effects that:

[0029] 1、The present application is aimed at the limitations of the existing stepped pre-calcination device, and proposes a spray blowing conveying bottom plate for effectively solving the uniform ventilation and sufficient pre-calcination of the accumulated and clustered alternative fuel, which can control the reaction process of alternative fuel cracking gasification and subsequent combustion, thereby solving the problems of incomplete combustion, skinning and plugging, large thermal system fluctuation, and uncontrollable NOx emission caused by the disposal of alternative fuel in the firing system, so as to overcome the bottleneck of difficult improvement of the alternative ratio.

[0030] 2、The pre-prepared spray blowing grate plate module in the present application contains at least two upwardly inclined supersonic airflow nozzles, which respectively play the functions of material turning and blowing, can spray the alternative fuel on the material receiving surface upward and forward at high speed, complete the forward conveying of the alternative fuel and the air disturbance of the alternative fuel which is not easy to contact air at the bottom of the material layer, especially at the root of the spray blowing grate plate module, increase the contact of the alternative fuel with high-temperature oxygen-containing air, and strengthen the combustion of the alternative fuel. Along the material flow direction, the material receiving surface of the spray blowing grate plate module is provided with different lengths, so that the spray blowing conveying bottom plate is designed in a gradient gradual distribution manner, thereby controlling the movement transmission and combustion speed of the alternative fuel, and avoiding the two extreme phenomena of insufficient local combustion and local high-temperature overfiring.

[0031] 3、The working gap of each spray blowing grate plate module in the spray blowing conveying bottom plate of the present application is provided with an intelligent control mode, the average temperature measured at the top of the combustion cavity can intelligently adjust the working interval of each spray blowing grate plate module, control the residence time and reaction process of the alternative fuel, and is beneficial to improve the burnout rate of the alternative fuel in the firing system, and has wider applicability to alternative fuels with unstable quality.

[0032] 4、The grate pre-combustion furnace of the present application is suitable for ventilation and conveying of alternative fuel and other sticky materials, the spray blowing conveying bottom plate is combined and arranged by using the pre-prepared spray blowing grate plate module, has the characteristics of inclined upward supersonic blowing airflow and gradient gradual distribution of materials, so that the sticky materials on the spray blowing conveying bottom plate are lifted upward and forward in a parabolic route, the ventilation disturbance of the materials at the bottom of the alternative fuel layer and the effect of continuous forward conveying can be controlled at the same time. In addition, the special channel design and upward outlet angle design of the airflow nozzle avoid the sudden cooling and heating stimulation of the cold air blown into the material receiving surface refractory material, effectively protect the service life of the spray blowing grate refractory material, and in combination with the intelligent spray blowing program, can effectively prevent the plugging of the channel by the sticky alternative fuel. BRIEF DESCRIPTION OF DRAWINGS

[0033] Fig. 1 is a structural schematic view of a pre-prepared composite spray blowing grate plate module provided by the embodiment of the present application;

[0034] Fig. 2 is a top view of the pre-prepared composite spray blowing grate plate module provided by the embodiment of the present application;

[0035] Fig. 3 is a structural schematic diagram of the injection conveying bottom plate according to the embodiment of the present application;

[0036] Fig. 4 is a layout schematic diagram of the injection conveying bottom plate according to the embodiment of the present application;

[0037] Fig. 5 is a structural schematic diagram of the grate pre-combustion furnace according to the embodiment of the present application;

[0038] Fig. 6 is a structural schematic diagram of the grate pre-combustion furnace according to the embodiment of the present application.

[0039] In the figures, 10, injection grate module; 101, shell; 102, wear-resistant castable; 103, air flow nozzle; 104, high-temperature SiC plate;

[0040] 20, discharge grate module;

[0041] 30, injection conveying bottom plate; 301, preheating section; 302, combustion section; 303, discharge section;

[0042] 40, combustion cavity; 401, alternative fuel inlet; 4011, alternative fuel feeding device; 4012, material scattering box; 402, high-temperature air inlet; 4021, high-temperature air inlet pipe; 4022, high-temperature air inlet louver valve; 403, sand inlet one; 4031, sand feeding flap valve one; 403a, sand inlet two; 4031a, sand feeding flap valve two;

[0043] 50, combustion furnace. DETAILED DESCRIPTION

[0044] The technical solutions in the embodiments of the present application will be described clearly and completely below with reference to the accompanying drawings in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, rather than all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative work fall within the protection scope of the present application.

[0045] The embodiment of the present application provides a prefabricated composite injection grate module, as shown in Figures 1 and 2, which is composed of a shell 101, wear-resistant castable 102 with good thermal shock stability filled in the shell, and at least two outlet inclined upward airflow nozzles 103 embedded in the wear-resistant castable. The nozzle of the airflow nozzle 103 is located on the receiving surface of the injection grate module, which is the upper surface of the injection grate module, and the receiving surface of the injection grate module is covered with a high-temperature-resistant SiC plate 104. Specifically, in the embodiment, the outside of the injection grate module is the shell 101, the inside of the shell 101 is filled with the wear-resistant castable 102 with good thermal shock stability, the wear-resistant castable 102 is embedded with two airflow nozzles 103, and the receiving surface is covered with a high-temperature-resistant SiC plate 104. The material of the shell 101 and the airflow nozzle 103 is heat-resistant steel material, and the temperature resistance is 1000-1300℃.

[0046] The injection grate module adopts two airflow nozzles 103 inclined upward along the receiving surface, and the airflow sprayed by the airflow nozzle 103 is sprayed upward at a certain angle with the horizontal direction, so that the sprayed material moves upward along the parabolic path. Specifically, along the material flow direction, the included angle γ1 between the spraying direction of the nozzle of the airflow nozzle located at the rear side and the receiving surface of the injection grate module is 10-35°, and the nozzle of this airflow nozzle is located at the overlapping joint of the two-stage injection grate module, and is inclined upward to play a role of turning over the material; the included angle γ2 between the spraying direction of the nozzle of the airflow nozzle located at the front side and the receiving surface of the injection grate module is 5-30°, and the nozzle of this airflow nozzle is located at the middle part of the injection grate module, playing a role of conveying forward and cooling the injection grate module; and γ1≥γ2, the two airflow nozzles jointly make the airflow entering the airflow nozzle be sprayed upward along the receiving surface of the injection grate module, and the material is sprayed upward to form a parabolic path, which can achieve a better injection effect and increase the contact time with high-temperature air.

[0047] The spraying angle of the airflow nozzle near the joint of the two-stage injection grate module is larger, so as to ensure that the corner is not easy to contact air and the material layer in the dead material area is higher, so as to increase the contact time of the alternative fuel and high-temperature air; the airflow spraying angle near the middle part of the receiving surface is slightly smaller, so that the reacted alternative fuel on the step is conveyed forward.

[0048] The injection grate module can adjust the spraying angle γ of the injection grate module and the pressure of the airflow nozzle gas source according to the bulk density of the alternative fuel, so as to control the appropriate forward speed of the alternative fuel.

[0049] The air flow nozzle 103 is gradually changed into a flat narrow form from the cross section of the inlet to the nozzle, and the instantaneous speed of the air flow released after the air flow nozzle blows is supersonic. The air inlet of the air flow nozzle is circular, and gradually changes into a flat narrow form to the air outlet, which can avoid large fuel entering the gap formed by the nozzle, and the air flow is released instantaneously after blowing through the narrow pipeline, and the instantaneous speed of the release can reach supersonic speed, which has a higher energy accelerating effect.

[0050] Each of the two air flow nozzles in the blowing grate module uses the same inlet for air supply, and the air flow supplied by the blowing grate module is high-pressure combustion-supporting air or fuel gas, and the instantaneous speed of the air flow released after blowing through the air flow nozzle can reach supersonic speed, which has a higher energy accelerating effect.

[0051] A blowing conveying bottom plate, as shown in FIGS. 3 and 4, is composed of a plurality of blowing grate modules 10 arranged in multiple levels in the longitudinal direction and multiple columns in the transverse direction and placed obliquely, and a discharge grate module 20 located at the end of the blowing conveying bottom plate. The blowing conveying bottom plate is arranged obliquely downward along the material flow direction. The blowing conveying bottom plate is divided into three zones along the material flow direction according to the combustion condition of the material: a preheating section 301, a combustion section 302, and a discharge section 303 in sequence. The preheating section, the combustion section, and the discharge section are respectively provided with different combinations of grate modules according to different combustion characteristics, forming a blowing conveying bottom plate with gradiently changing distribution of materials, and realizing the effect of upward rolling of the bottom material and forward conveying of the alternative fuel on the blowing conveying bottom plate.

[0052] The blowing grate module 10 is arranged obliquely downward along the material flow direction, and the inclination angle a is 2-10°. Between the two adjacent levels of blowing grate modules, the nozzle of the air flow nozzle located at the last side along the material flow direction is located at the overlapping junction of the upper and lower blowing grate modules.

[0053] According to the different expected residence times of the three zones, the length of the material receiving surface of a single blowing grate module in the preheating section 301 is greater than that in the combustion section 302. Finally, the angles of the material receiving surface of the entire blowing conveying bottom plate in the three zones are different: the preheating section 301 is provided with 1-3 levels of blowing grate modules, and the preheating section angle b1 is 15-28°; the combustion section 302 is provided with 2-6 levels of blowing grate modules, and the combustion section angle b2 is 28-35°; the discharge section 303 is the bottom step of the grate precombustion furnace, and is provided with 1-2 levels of discharge grate modules, and the discharge section angle b3 is 45-60°; and b1 < b2 < b3. The above gradiently changing distribution of materials serves as a means for controlling the temperature in the combustion furnace.

[0054] The discharge grate module 20 is composed of a shell and wear-resistant castable filled in the shell, and the wear-resistant castable of the discharge grate module is not provided with an air flow nozzle.

[0055] Example 1

[0056] As shown in Figure 5, the grate pre-combustion furnace for processing alternative fuel includes a combustion chamber 40 and a jet conveying bottom plate 30 located at the bottom of the combustion chamber, and the discharge grate plate module of the jet conveying bottom plate extends into the combustion furnace 50; the combustion chamber 40 is provided with an alternative fuel inlet 401, a high-temperature air inlet 402 and a plurality of sand inlets 403, one end of the combustion chamber is provided with the alternative fuel inlet 401 and the high-temperature air inlet 402, and the other end of the combustion chamber is connected with the combustion furnace 50. Specifically, the discharge grate plate module 303 of the discharge section extends into the combustion furnace 50 to discharge, and the upward airflow in the combustion furnace is more likely to carry the unburned substances for further combustion in the combustion furnace.

[0057] The alternative fuel inlet 401 is located below the high-temperature air inlet 402; the alternative fuel inlet 401 is provided with an alternative fuel feeding device 4011, and the alternative fuel is fed into the combustion chamber 40 by the alternative fuel feeding device 4011. The alternative fuel feeding device can adopt a spiral reamer feeding mode to push the alternative fuel into the combustion chamber. The high-temperature air inlet 402 is provided with a high-temperature air inlet pipe 4021 connected with the combustion chamber, and the high-temperature air inlet pipe 4021 is provided with a high-temperature air inlet louver valve 4022. The sand inlets 403 are located at the dome of the combustion chamber and the high-temperature air inlet, and each sand inlet 403 is provided with a sand feeding flap valve 4031.

[0058] The alternative fuel enters from the inlet of the alternative fuel feeding device, is pushed into the grate pre-combustion furnace by the spiral reamer, and is dispersed and lifted under the action of high-speed airflow in the airflow nozzle of the jet grate plate module, and is conveyed to the combustion furnace; the hot air for combustion enters from the high-temperature air inlet 402, and the air volume can be adjusted by the high-temperature air inlet louver valve 4022 according to the combustion temperature and oxygen content. One sand inlet 403 is arranged at the dome of the combustion chamber, and one sand inlet 403a is arranged on the air inlet pipe, and the amount of sand entering the sand inlet 403 and the sand inlet 403a is controlled by the sand feeding flap valve 4031 and the sand feeding flap valve 4031a. The sand is a calcium-based mineral material, which can not only control the temperature in the combustion chamber of the grate pre-combustion furnace, reduce the agglomeration of the alternative fuel, make it dispersed and easy to ventilate, but also can play a catalytic role of calcium-based mineral material on directional thermal cracking of alternative fuel products.

[0059] The combustion cavity top is provided with multiple temperature measuring points, the combustion cavity top is provided with a high-temperature camera, and the outlet is provided with a gas component measuring point. According to the monitored temperature distribution, the combustion state and the gas component at the outlet, the high-temperature air inlet damper 4022, the sand feeding flap valve one 4031 and the sand feeding flap valve two 4031a are adjusted to control the high-temperature air inlet amount, the sand feeding amount, and the intelligent control of the spraying and conveying bottom plate spraying operation mode, so that the alternative fuel movement speed and the combustion speed can be intelligently controlled.

[0060] As shown in FIG. 4, the spraying operation mode of the spraying and conveying bottom plate is set according to the principle of traversing all column small cycles (from the first column to the nth column small cycle), the adjacent two spraying grate modules of different levels are at least interval 1 level step, and the spraying order of each level is from low temperature zone to high temperature zone according to the dome temperature monitoring data; the same level spraying grate module is not adjacent to the spraying, so that the material will not enter the grate seam formed by the nozzle of the adjacent column spraying grate module, and finally all the spraying grate modules are traversed.

[0061] The working frequency of the spraying grate module is calculated according to the multi-point temperature average value measured by the multiple temperature measuring points at the top of the combustion cavity, and the formula is as follows:

[0062] Wherein, T avg is the multi-point temperature average value, unit: °; τ iintel is the interval time of each adjacent two spraying, unit: s.

[0063] The intelligent control of the spraying operation mode of the spraying and conveying bottom plate is to obtain the average value of multiple position temperatures through multiple temperature monitoring devices (i.e. multiple temperature measuring points) installed at the top of the combustion cavity, and then calculate the working frequency of the spraying grate module through the above formula.

[0064] This embodiment is especially suitable for the treatment of combustible waste with a moisture content of less than 20%, such as biomass, pretreated waste spinning, plastic, RDF, etc.

[0065] Example 2

[0066] The difference from example 1 is that:

[0067] For some sticky alternative fuels such as waste spinning, municipal solid waste, sludge, etc. with uncontrolled 3D size and moisture content of more than 20%, a combination of spiral reamer feeding and high-temperature air inlet pipe feeding can be used for feeding into the grate pre-combustion furnace, and the sand inlet is located at the dome of the combustion cavity. As shown in FIG. 6, the specific process is as follows:

[0068] The alternative fuel is sent to the alternative fuel feeding device 4011 through the material distribution valve, fed by the spiral auger, and directly scattered into the high-temperature air inlet pipe 4021 through the scattering box 4012 arranged on the high-temperature air inlet pipe 4021, and then enters the grate pre-combustion furnace together with the high-temperature air, which can dry part of the moisture in the alternative fuel, replace the sand material to adjust the high-temperature air inlet temperature, and reduce the pressure of the spiral auger feeding, so as to avoid the winding and crushing of long strip high-moisture sticky material on the spiral auger.

[0069] For the processing of high-moisture sticky alternative fuel, the angles γ1 and γ2 between the jet direction of the jet nozzle of the jet grate module and the receiving surface of the jet grate module can be appropriately increased, the role of high-speed airflow upward loosening and lifting is emphasized, the distance of forward conveying is reduced, the contact time with high-temperature oxygen-containing air is increased, and the residence time of the alternative fuel in the pre-combustion furnace is increased.

[0070] When the jet nozzle of the jet grate module uses high-pressure fuel gas hydrogen to scatter the alternative fuel on the receiving surface, the hydrogen and the alternative fuel are pre-mixed and dispersed in the pre-combustion furnace, the hydrogen is ignited to reach the ignition point of the alternative fuel at the bottom of the pre-combustion furnace by using the characteristics of fast burning speed of hydrogen, and the burning process is accelerated.

[0071] A plurality of temperature measuring points are arranged at the top of the combustion chamber, a high-temperature camera is arranged at the top of the combustion chamber, and a gas composition measuring point is arranged at the outlet. According to the monitored temperature distribution, the combustion state and the gas composition at the outlet, the high-temperature air inlet louvre valve 4022, the sand material feeding flap valve 4031 and the scattering box 4012 are adjusted to control the high-temperature air inlet amount, the sand material feeding amount, the alternative fuel feeding amount at the scattering box, and the jetting work mode and work frequency of the jetting conveying bottom plate are intelligently controlled, so as to intelligently control the movement speed and the burning speed of the alternative fuel.

[0072] Example 3

[0073] The industrial analysis of the alternative fuel used in the A project is shown in Table 1. Overall, the ash content of waste spinning, leather, wood chips and wood blocks is low, and the volatile matter is high. Among them, the waste spinning has a high calorific value, and the calorific value of the wood chips and wood blocks is low.

[0074] Table 1 Industrial analysis of alternative fuel samples used in the A project

[0075] Table 2 Thermogravimetric analysis results of alternative fuel used in the A project

[0076] The thermogravimetric analysis of all alternative fuels in the A project shows that:

[0077] The thermal weight loss of waste spinning starts at about 316℃ and ends at about 671℃, and the combustion activity is general.

[0078] The thermal weightlessness starting temperature of the leather is about 307 DEG C, and the ending temperature is about 399 DEG C, and the combustion activity is better;

[0079] The thermal weightlessness starting temperature of the wood chips is about 271 DEG C, and the ending temperature is about 495 DEG C, and the combustion activity is better;

[0080] The thermal weightlessness starting temperature of the wood block is about 274 DEG C, and the ending temperature is about 495 DEG C, and the combustion activity is better.

[0081] According to the characteristics of the alternative fuel, the pre-combustion furnace structure is further designed, the heat of the combustion furnace is replaced by 40%, and the feeding amount is 10t / h, the spraying conveying bottom plate is transversely arranged as 4 columns, and longitudinally arranged as 12 levels (including 1 level of preheating section, 10 levels of combustion section and 1 level of discharging section). The oxygen content in the grate pre-combustion furnace can be adjusted, and the cracking and combustion process of the fuel are controlled by adjusting the oxygen content. For the alternative fuel with high volatile matter in the A project, the air equivalence ratio in the pre-combustion furnace can be appropriately reduced, and the alternative fuel after preliminary heat treatment stays in the grate pre-combustion furnace for 15-20 minutes, and then enters the combustion furnace with high-temperature flue gas for further complete combustion. After the heat treatment of the grate pre-combustion furnace, not only the heat utilization rate of the alternative fuel itself can be improved, but also the influence on the combustion furnace kiln condition is reduced, and the adverse effect of the fuel gas out of the grate pre-combustion furnace on the pollutant emission of the combustion furnace is reduced.

[0082] The above embodiments of the present application are described in detail, but the content is only the preferred embodiment of the present application, and cannot be considered as limiting the scope of the present application. Any equivalent changes and improvements made according to the scope of the present application should still belong to the patent coverage range of the present application.

Claims

1. A precast composite injection lacing panel module, characterized by, The precast composite jet grating module is composed of a shell, wear-resistant castable filled in the shell and at least two outlet inclined upward airflow nozzles embedded in the wear-resistant castable; the jet nozzles are located on the receiving surface of the jet grating module, and the receiving surface of the jet grating module is the upper surface of the jet grating module; the included angle γ1 between the jet direction of the jet nozzle located at the last side and the receiving surface of the jet grating module is 10-35° along the material flow direction, and the included angles between the jet directions of the other jet nozzles and the receiving surface of the jet grating module are equal to the included angle γ1 or gradually decrease; the airflow entering the jet nozzles is jetted upward along the receiving surface of the jet grating module, and the material is jetted upward to form a parabolic path, thereby increasing the sufficient contact time with high-temperature air.

2. The pre-fabricated composite lancing grid module of claim 1, wherein: The shell and the jet nozzles are made of heat-resistant steel with a temperature resistance of 1000-1300℃.

3. The pre-fabricated composite lancing grid module of claim 1, wherein: The receiving surface of the jet grating module is covered with high-temperature-resistant SiC plates.

4. The pre-fabricated composite lancing grid module of claim 1, wherein: The cross section of the jet nozzle gradually changes into a flat and narrow form from the inlet to the jet orifice, and the instantaneous speed of the jet airflow released by the jet nozzle is supersonic.

5. The pre-fabricated composite lancing grid module of claim 1, wherein: Each jet nozzle in each jet grating module is supplied with air through the same inlet, and the air supplied to the jet grating module is high-pressure combustion-supporting air or fuel gas.

6. A blow-through delivery deck characterized by: The jet conveying bottom plate is composed of jet grating modules arranged in multiple levels in the longitudinal direction and multiple columns in the transverse direction and inclined and discharge grating modules located at the end of the jet conveying bottom plate, the jet grating modules are the precast composite jet grating modules of any one of claims 1-5, the jet conveying bottom plate is arranged inclined downward along the material flow direction, and the jet conveying bottom plate is divided into three zones along the material flow direction, namely a preheating zone, a combustion zone and a discharge zone in sequence, different grating module combinations are arranged in the preheating zone, the combustion zone and the discharge zone respectively, a jet conveying bottom plate with gradient changing distribution is formed, and bottom material upward movement and rolling and forward conveying of the replacement fuel on the jet conveying bottom plate are realized.

7. The blow-through conveyor deck according to claim 6, wherein: The jet grating modules are arranged inclined downward along the material flow direction, and the inclination angle α is 2-10°; the jet orifice of the airflow nozzle located at the last side between two adjacent jet grating modules along the material flow direction is located at the overlapping joint of the upper and lower jet grating modules.

8. The blow-through conveyor deck according to claim 6, wherein: The length of the receiving surface of a single jet grating module in the preheating zone is greater than the length of the receiving surface of a single jet grating module in the combustion zone, 1-3 jet grating modules are arranged in the preheating zone, and the preheating zone angle β1 is 15-28°; 2-6 jet grating modules are arranged in the combustion zone, and the combustion zone angle β2 is 28-35°; 1-2 discharge grating modules are arranged in the discharge zone, and the discharge zone angle β3 is 45-60°; and β1<β2<β3.

9. A grate pre-combustion furnace for processing alternative fuel, comprising a combustion chamber and the injection and conveying bottom plate of any one of claims 6-8, the injection and conveying bottom plate being located at the bottom of the combustion chamber, the discharge grate plate modules of the injection and conveying bottom plate extending into the combustion furnace, the combustion chamber being provided with an alternative fuel inlet, a high-temperature air inlet and a sand inlet, the combustion chamber being provided with the alternative fuel inlet and the high-temperature air inlet at one end, the high-temperature air inlet being connected to a high-temperature air inlet pipe, the other end of the combustion chamber being connected to the combustion furnace, and the sand inlet being located at the dome of the combustion chamber and / or at the high-temperature air inlet.

10. The grate precombustion furnace for processing alternative fuels according to claim 9, characterized in that: The sand is a calcium-based mineral material.

11. The grate precombustion furnace for processing alternative fuels according to claim 9, characterized in that: The top of the combustion chamber is provided with a plurality of temperature measuring points for monitoring temperature distribution and high-temperature cameras for monitoring combustion state, and the outlet of the combustion chamber is provided with gas composition measuring points for monitoring outlet gas composition.

12. The grate precombustion furnace for processing alternative fuels according to claim 9, characterized in that: The alternative fuel inlet is located at and / or below the high-temperature air inlet; when located at the high-temperature air inlet, the alternative fuel inlet is provided with a distribution box, and the alternative fuel is fed into the high-temperature air inlet pipe together with the high-temperature air by the distribution box; when located below the high-temperature air inlet, the alternative fuel inlet is provided with an alternative fuel feeding device, and the alternative fuel is fed into the combustion chamber by the alternative fuel feeding device.

13. The grate precombustion furnace for processing alternative fuels according to claim 9, characterized in that: The injection and conveying bottom plate is set according to the principle of traversing all columns in small cycles, the adjacent two injection grate plate modules of different stages are at least separated by one stage, the order of injection of each stage is from low-temperature zone to high-temperature zone according to the dome temperature monitoring data, the non-adjacent injection is used for the same stage injection grate plate module, so that the material will not enter the grate gap formed by the injection nozzles of the adjacent column injection grate plate modules, and finally all the injection grate plate modules are traversed. The working frequency of the injection grid module is calculated according to the multi-point temperature average value measured by the multiple temperature measuring points at the top of the combustion chamber, and the formula is as follows: wherein T avg is the average temperature of the multiple points, in °; τ 1intel is the interval time between each adjacent two times of spraying, in s.

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