Water-cooled wall lining and gasifier containing the same

Abstract

The present invention discloses a water-cooled wall lining and a gasifier containing the same. The water-cooled wall lining includes a plurality of water-cooled tubes and a connecting rib plate; the plurality of water-cooled tubes are arranged circumferentially, and two adjacent water-cooled tubes are connected by the connecting rib plate to form a circumferentially sealed gasification chamber cavity; the connecting rib plate is arranged outside the circumferential center line of the water-cooled tube; the distance between the circumferential center line of the connecting rib plate and the circumferential center line of the water-cooled tube is an offset distance y, 0﹤y﹤d / 2, d is the outer diameter of the water-cooled tube; two adjacent water-cooled tubes and the connecting rib plate form an insulation groove with an open end, and the insulation groove is filled with refractory material; the outer side is the side away from the gasification chamber cavity. The water-cooled wall lining can effectively reduce the heat loss of the gasifier wall and improve the utilization efficiency of gasification raw materials and gasification agents.

Description

Technical Field

[0001] The invention relates to a water-cooled wall lining and a gasifier comprising the same. Background Art

[0002] Coal gasification technology is one of the key technologies for clean and efficient utilization of coal and other carbon-containing materials today. It is also the main way to convert primary energy into clean secondary energy. This technology is mainly used in synthetic ammonia, synthetic methanol, refinery hydrogen production, blast furnace reduction ironmaking chemical metallurgical industry and combined cycle power generation equipment. Entrained-bed gasification technology has the characteristics of high carbon conversion rate and strong applicability of coal types. It has become the mainstream technology for coal gasification to prepare raw gas. The salient features of entrained-bed coal gasification technology are high temperature, high pressure and liquid slag discharge. Therefore, the protection of the metal shell of the gasifier has become one of the key technologies of the gasifier.

[0003] The lining of the existing fluidized bed gasification technology can be divided into two categories: one is the refractory brick type gasification technology represented by multi-nozzle opposed water-coal slurry gasification technology and GE water-coal slurry gasification technology, which has the advantages of small wall heat loss and high thermal efficiency, but needs to be replaced partially or completely regularly; the other is the water-cooled wall type gasification technology represented by Shell pulverized coal gasification technology, SE Dongfang furnace pulverized coal gasification technology, and Jinhua furnace water-coal slurry gasification technology, which has the advantages of high temperature resistance, ablation resistance, and low maintenance cost, but has the limitations of large wall heat loss, low thermal efficiency, and large interlayer maintenance space. Chinese patent document CN2863802Y discloses a pressurized fluidized bed water-cooled wall gasification reactor, in which a slag nail net is provided on the inner side of the membrane water-cooled wall refractory lining, and a refractory coating is provided inside the slag nail net, and the inner side of the refractory coating is a solid slag layer and a liquid flowing slag layer in sequence. However, it has the defects of insufficient filling space of the refractory coating and large wall heat loss. During the operation of the water-cooled wall, frequent maintenance is required due to ablation, resulting in high maintenance costs. In addition, a large interlayer maintenance space needs to be reserved, resulting in low space utilization of the gasifier.

[0004] With the further improvement of the high reliability, high efficiency and low cost of coal gasification technology, it is urgent to develop a water-cooled wall refractory lining and a gasifier with low heat loss, low maintenance cost and high space utilization of the gasifier. Summary of the invention

[0005] The technical problem to be solved by the present invention is to overcome the defects of the prior art membrane water-cooled wall, such as large heat loss on the wall surface, low thermal efficiency, and low effective utilization rate of the gasifier space, and provide a water-cooled wall lining and a gasifier containing the same. The water-cooled wall lining provided by the present invention can greatly reduce the heat loss on the wall surface, improve the thermal efficiency, and at the same time improve the effective utilization rate of the gasifier space and improve the processing capacity.

[0006] In order to achieve the above object, the present invention adopts the following technical solutions:

[0007] The present invention provides a water-cooled wall lining, which includes a plurality of water-cooled tubes and connecting ribs;

[0008] The plurality of water cooling tubes are arranged circumferentially, and two adjacent water cooling tubes are connected by the connecting rib plate to form a circumferentially sealed gasification chamber cavity;

[0009] The connecting rib is arranged outside the circumferential center line of the water cooling pipe; the distance between the circumferential center line of the connecting rib and the circumferential center line of the water cooling pipe is the offset distance y, 0﹤y﹤d / 2, d is the outer diameter of the water cooling pipe;

[0010] Two adjacent water-cooling pipes and the connecting rib plate form a heat-insulating groove with one end open, and the heat-insulating groove is filled with refractory material;

[0011] The outer side is a side away from the cavity of the gasification chamber.

[0012] In the present invention, the water cooling tube can be conventional in the art, preferably a round tube.

[0013] In the present invention, those skilled in the art should be aware that the heat exchange medium flowing inside the water-cooling tube can be conventional in the art, preferably water.

[0014] In the present invention, the diameters of different water-cooling pipes may be the same or different, and are preferably the same.

[0015] In the present invention, the tube spacing between any two adjacent water-cooling tubes may be the same or different, preferably the same, and the tube spacing refers to the distance between the radial center lines of the two adjacent water-cooling tubes.

[0016] The difference between the tube spacing between two adjacent water-cooling tubes and the sum of the radii of the two adjacent water-cooling tubes is the tube gap.

[0017] The tube gap may be 30 to 200 mm, preferably 50 to 180 mm, and more preferably 150 mm.

[0018] In the present invention, the water cooling pipe and the connecting rib plate may be connected in a conventional manner in the art, preferably by welding.

[0019] In the present invention, the inner side of the water-cooling tube and the inner side of the connecting rib are preferably also coated with a refractory coating.

[0020] The inner side refers to the surface directly exposed to the cavity of the gasification chamber.

[0021] Among them, the material of the refractory coating can be conventional in the field, preferably a slag-resistant refractory material, further preferably one or more of a magnesium-chromium refractory material, a corundum composite refractory material, a magnesium-carbon refractory material, a magnesium-calcium refractory material, and a SiC refractory material, and further preferably a SiC refractory material.

[0022] The thickness of the refractory coating may be 5-30 mm, preferably 16 mm.

[0023] In the present invention, the refractory material can be filled in the insulation groove in a conventional manner in the art. Preferably, a slag nail net is further provided in the insulation groove, and the refractory material is filled in the slag nail net.

[0024] In the present invention, the refractory material may be conventional in the art, preferably a slag resistant refractory material, further preferably one or more of a magnesium-chromium refractory material, a corundum composite refractory material, a magnesium-carbon refractory material, a magnesium-calcium refractory material, and a SiC refractory material, and further preferably a SiC refractory material.

[0025] The filling thickness of the refractory material may be 20-80 mm, for example, 30 mm, 40 mm, 50 mm, 60 mm, 70 mm, preferably 50 mm.

[0026] During the operation of the water-cooled wall lining, a solid slag layer and a liquid flowing slag layer will also form on the surface of the refractory material. The solid slag layer and the liquid slag layer will further increase the thermal resistance, reduce the heat flux density, and reduce the heat loss of the wall surface; at the same time, the formation of the slag layer can effectively reduce the erosion and corrosion of the slag on the refractory material, play the role of slag against slag, and extend the service life of the refractory material.

[0027] The present invention further provides a gasifier, wherein the furnace body side wall of the gasifier comprises:

[0028] A water-cooled wall lining, wherein the water-cooled wall lining is the water-cooled wall lining described above;

[0029] The metal shell is sleeved on the outside of the water-cooled wall lining to form a sandwich space.

[0030] In the present invention, the gasifier can be conventional in the art, such as a single-nozzle top-mounted gasifier, a four-nozzle side-mounted bottom-gas outlet gasifier, or a four-nozzle side-mounted top-gas outlet gasifier.

[0031] In the present invention, the water-cooled wall lining of the gasifier is generally divided from top to bottom into an upper tapered water-cooled wall section, a straight water-cooled wall section and a lower tapered water-cooled wall section according to the convention in the art.

[0032] In the present invention, the burner of the gasifier is preferably provided with a burner water-cooled wall connected to the upper constricted water-cooled wall section. The burner water-cooled wall can be arranged on the top or side of the gasifier. The surface of the burner water-cooled wall can be coated with a refractory coating.

[0033] In the present invention, the lower slag mouth section of the gasifier is preferably provided with a slag mouth section water-cooled wall connected to the lower shrinkage water-cooled wall section.

[0034] The slag opening section water-cooled wall may be a coil-type water-cooled wall.

[0035] The surface of the water-cooled wall of the slag opening section may be coated with a refractory coating.

[0036] In the present invention, the gasifier generally further includes a synthesis gas outlet and a slag quenching chamber according to the convention in the art; the synthesis gas outlet can be arranged at the bottom of the lower shrinking water-cooled wall section or the top of the upper shrinking water-cooled wall section; the slag quenching chamber can be arranged at the lower part of the water-cooled wall of the slag mouth section, for quenching the slag, and can also be used for the joint quenching of the slag and the synthesis gas.

[0037] In the present invention, the water-cooled wall lining may adopt a conventional water-cooled wall form in the art, such as a shell-and-tube water-cooled wall or a coil-and-tube water-cooled wall, preferably a shell-and-tube water-cooled wall.

[0038] When the water-cooled wall lining is a tube-type water-cooled wall, the upper shrinkage water-cooled wall section and the lower shrinkage water-cooled wall section can generally be shrunken by means of pipe drawing.

[0039] On the basis of being in accordance with the common sense in the art, the above-mentioned preferred conditions can be arbitrarily combined to obtain the preferred embodiments of the present invention.

[0040] The reagents and raw materials used in the present invention are commercially available.

[0041] The positive and progressive effects of the present invention are:

[0042] The water-cooled wall lining provided by the present invention further reduces the heat loss of the wall surface compared with the prior art, and the heat loss of the wall surface can be reduced by more than 30%, and in a preferred embodiment, it can even be as high as 50%. At the same time, the specific coal consumption and specific oxygen consumption of the gasifier can be reduced by more than 1% compared with the gasifier of the prior art, and can even be as high as nearly 3%; the specific oxygen consumption can be reduced by more than 2% compared with the prior art, and can even be as high as 2.73%, thereby improving the utilization efficiency of gasification raw materials and gasification agents. The ring width of the interlayer space of the gasifier can be reduced from the traditional 700mm to 200mm~600mm, and the utilization rate of the gasifier space can be increased by 10%~83% compared with the prior art, and the maintenance cost of the water-cooled wall of the gasifier is reduced compared with the prior art. BRIEF DESCRIPTION OF THE DRAWINGS

[0043] Figure 1 It is a schematic diagram of the structure of a water-cooled wall lined gasifier;

[0044] Figure 2 It is a schematic diagram of the water wall lining structure;

[0045] Figure 3 It is a schematic diagram of the local structure of the water-cooled wall lining;

[0046] Figure 4 This is a schematic diagram of the water-cooled wall structure of the slag mouth section;

[0047] Figure 5 This is a schematic diagram of the burner seat water-cooled wall structure;

[0048] Figure 6 It is a partial structural diagram of the water-cooled wall lining of Comparative Example 1;

[0049] Figure 7 This is a schematic diagram of the local structure of the water-cooled wall lining of Comparative Example 2.

[0050] V1-gasification chamber cavity; V21-straight water-cooled wall; V22-lower contraction water-cooled wall section; V23-upper contraction water-cooled wall section; V3-sandwich space; V4-metal wall; V5-slag mouth section water-cooled wall; V6-burner seat water-cooled wall; V7-synthesis gas outlet; V8-slag quenching chamber; G1-water-cooling pipe; Z1-insulation groove; x-tube gap; L-tube spacing; y-offset distance; m-connecting rib plate thickness; d-outer diameter of water-cooling pipe. DETAILED DESCRIPTION

[0051] The present invention is further described below by way of examples, but the present invention is not limited to the scope of the examples. The experimental methods in the following examples without specifying specific conditions are carried out according to conventional methods and conditions, or selected according to the product specifications.

[0052] Example 1

[0053] A water-cooled wall gasifier with a daily processing capacity of 1,500 tons of coal uses pulverized coal as raw material for gasification; the gasification pressure is 4.0 MPa, and the refractory lining is a tube-type water-cooled wall. The coal consumption of the gasifier is 1,500 tons / day, the inner diameter D of the water-cooled wall of the gasification chamber is 2,400 mm, the height H of the gasification chamber is 8,000 mm, and the gasification temperature is 1,500 °C. The outer diameter of the water-cooled tube is 38 mm, the tube gap is 150 mm, the thickness of the connecting rib plate is 8 mm, the center line offset distance of the connecting rib plate is 15 mm, the surface of the water-cooled tube, the surface of the connecting rib plate, the water-cooled wall of the burner and the water-cooled wall of the slag mouth section are all coated with a 16 mm SiC refractory coating, and the surface of the connecting rib plate is filled with a 50 mm thick SiC refractory material. Other structural parameters are shown in Table 1.

[0054] Example 2

[0055] The processing capacity of the gasifier is 2000 tons / day of coal, water-coal slurry is used as raw material for gasification, the gasification pressure is 6.5 MPa, the gasification temperature is 1300° C., and the outer diameter of the metal shell of the gasifier is 3000 mm. Other conditions are the same as those in Example 1.

[0056] Example 3

[0057] The processing capacity of the gasifier is 2000 tons / day of coal, with water-coal slurry as the raw material for gasification, gasification pressure of 6.5Mpa, gasification temperature of 1300℃. The tube spacing is 68mm, the tube gap is 30mm, the surface of the connecting rib plate is filled with 20mm thick SiC refractory material, the outer diameter of the metal shell of the gasifier is 3600mm, and other conditions are the same as 1.

[0058] Example 4

[0059] The processing capacity of the gasifier is 2000 tons / day of coal, with water-coal slurry as raw material for gasification, gasification pressure of 6.5Mpa, and gasification temperature of 1300℃. The tube spacing is 248mm, the tube gap is 180mm, the centerline offset distance of the connecting rib plate is 30mm, the surface of the connecting rib plate is filled with 80mm thick SiC refractory material, the outer diameter of the metal shell of the gasifier is 2800mm, and other conditions are the same as 1.

[0060] Comparative Example 1

[0061] The water-cooled wall gasifier of the prior art has a water-cooled wall structure such as Figure 6 As shown, the connecting rib plate is connected to the center line of the water cooling pipe, and the connecting rib plate and the surface of the water cooling pipe are not coated 1. The pipe gap is 12mm, the inner diameter of the metal shell is 3800mm, and other conditions are the same as those in Example 1.

[0062] Comparative Example 2

[0063] The water-cooled wall gasifier of the prior art has a structure of a water-cooled wall in the gasification chamber. Figure 7 As shown, the center line of the connecting rib plate coincides with the center line of the water cooling pipe, the surface of the connecting rib plate, the surface of the water cooling pipe, the water cooling wall of the burner and the water cooling wall of the slag mouth section are all coated with SiC refractory material, the coating thickness is 16mm, and the surface of the connecting rib plate is no longer filled with refractory material. The water-coal slurry is used as the raw material for gasification, the gasification temperature is 1300℃, the gasification pressure is 6.5Mpa, and the coal consumption of the gasifier is 2000 tons / day. Other conditions are the same as those in Example 1.

[0064] Effect Example

[0065] The heat loss ratio of the gasifier is calculated by simulation software Computational Fluid Dynamics (CFD), and the calculation formula is as follows:

[0066]

[0067] Wherein, R is the heat loss ratio, A is the water-cooled wall area of ​​the gasifier, K is the local thermal conductivity, qcoal is the coal mass flow rate kg / s, and Hcoal is the calorific value of coal.

[0068] The specific coal consumption is the mass of coal consumed per thousand standard cubic meters of synthesis gas (CO+H2). This value is calculated by the process simulation software Aspen.

[0069] The specific oxygen consumption is the mass of oxygen consumed per thousand standard cubic meters of synthesis gas (CO+H2), and this value is calculated by the process simulation software Aspen.

[0070] Table 1 Gasifier parameter settings and effect comparison table

[0071]

[0072]

Claims

1. A water-cooled wall lining, characterized in that: It includes a plurality of water cooling pipes and connecting rib plates; The plurality of water cooling tubes are arranged circumferentially, and two adjacent water cooling tubes are connected by the connecting rib plate to form a circumferentially sealed gasification chamber cavity; The connecting rib is arranged outside the circumferential center line of the water cooling pipe; the distance between the circumferential center line of the connecting rib and the circumferential center line of the water cooling pipe is the offset distance y, 0﹤y﹤d / 2, d is the outer diameter of the water cooling pipe; Two adjacent water-cooling pipes and the connecting rib plate form a heat-insulating groove with one end open, and the heat-insulating groove is filled with refractory material; The outer side is a side away from the central axis of the gasification chamber cavity.

2. The water-cooled wall lining according to claim 1, characterized in that: The difference between the distance between the radial center lines of two adjacent water-cooling pipes and the sum of the radii of the two adjacent water-cooling pipes is 30 to 200 mm.

3. The water wall lining according to claim 2, characterized in that: The difference between the distance between the radial center lines of two adjacent water-cooling pipes and the sum of the radii of the two adjacent water-cooling pipes is 50 to 180 mm.

4. The water wall lining according to claim 3, characterized in that: The difference between the distance between the radial center lines of two adjacent water-cooling pipes and the sum of the radii of the two adjacent water-cooling pipes is 150 mm.

5. The water wall lining according to claim 1, characterized in that: The surface of the water-cooling pipe and the inner side of the connecting rib plate are also coated with a fire-resistant coating.

6. The water-cooled wall lining according to claim 5, characterized in that: The refractory material and the refractory coating are independently slag-resistant refractory materials; And / or, the thickness of the refractory coating is 5-30 mm.

7. The water-cooled wall lining according to claim 6, characterized in that: The materials of the refractory material and the refractory coating are independently selected from one or more of a magnesium-chromium refractory material, a corundum composite refractory material, a magnesium-carbon refractory material, a magnesium-calcium refractory material, and a SiC refractory material; And / or, the thickness of the refractory coating is 16 mm.

8. The water-cooled wall lining according to claim 7, characterized in that: The materials of the refractory material and the refractory coating are independently SiC refractory materials.

9. The water-cooled wall lining according to claim 1, characterized in that: A slag nail net is also provided in each of the heat-insulating grooves, and the refractory material is filled in the slag nail net.

10. The water-cooled wall lining according to claim 1, characterized in that: The thickness of the refractory material is 20 to 80 mm.

11. The water-cooled wall lining according to claim 10, characterized in that: The thickness of the refractory material is 30 mm, 40 mm, 50 mm, 60 mm or 70 mm.

12. The water-cooled wall lining according to claim 11, characterized in that: The thickness of the refractory material is 50 mm.

13. A gasifier, characterized in that: The furnace body side wall of the gasifier comprises: a water-cooled wall lining, wherein the water-cooled wall lining is the water-cooled wall lining according to any one of claims 1 to 12; The metal shell is sleeved on the outside of the water-cooled wall lining to form a sandwich space.

14. The gasifier according to claim 13, characterized in that: The water-cooled wall lining of the gasifier is divided into an upper shrinking water-cooled wall section, a straight water-cooled wall section and a lower shrinking water-cooled wall section from top to bottom; A burner water-cooled wall is provided at the burner of the gasifier, and the burner water-cooled wall is connected to the upper shrinkage water-cooled wall section; The lower slag mouth section of the gasifier is provided with a slag mouth section water-cooled wall, and the slag mouth section water-cooled wall is connected to the lower shrinkage water-cooled wall section; Wherein, the surface of the burner water-cooled wall is coated with a refractory coating; and / or, the surface of the slag hole section water-cooled wall is coated with a refractory coating.

15. The gasifier according to claim 14, characterized in that: The gasifier is also provided with a synthesis gas outlet and a slag quenching chamber; Among them, the synthesis gas outlet is arranged at the bottom of the lower shrinkage water-cooled wall section or the top of the upper shrinkage water-cooled wall section; the slag quenching chamber is arranged at the lower part of the slag mouth section water-cooled wall, which is used for quenching the slag or for quenching the slag and synthesis gas together.

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