CN213396691U - High-thermal-shock-resistance honeycomb ceramic heat accumulator - Google Patents

Abstract

The utility model discloses a high thermal shock resistance's honeycomb ceramic heat accumulator, it includes the body, be provided with a plurality of honeycomb pore of arranging according to the law on two sides about running through in the body, be provided with a plurality of expansion joints that are linked together with honeycomb pore in the body on the lateral surface of body, along honeycomb pore axis direction, the expansion joint includes one or several kinds in horizontal expansion joint, longitudinal expansion joint, the slant expansion joint. The utility model discloses a set up the dilatation joint of the various forms that are linked together with the honeycomb pore on the outside of honeycomb ceramic heat accumulator, improved thermal shock resistance greatly, far exceed national standard level, avoided making RTO (RCO) equipment shut down because of the fracture of honeycomb ceramic heat accumulator is cracked when the production is nervous in mill to retrieve because of the economic loss that the production line stopped production for more than ten days changes the honeycomb ceramic heat accumulator and cause.

Description

High-thermal-shock-resistance honeycomb ceramic heat accumulator

Technical Field

The patent of the utility model relates to a honeycomb ceramic heat accumulator technical field that is relevant especially relates to a honeycomb ceramic heat accumulator with high thermal shock resistance of taking expansion joint.

Background

The honeycomb ceramic heat accumulator is a core component of heat accumulating type high temperature air combustion technology (HTAC) in the industries of metallurgy, machinery, chemical industry and the like, greatly reduces NOx emission while recovering flue gas waste heat and promoting efficient combustion to save energy, and mostly replaces other ceramics in RTO devices, heat accumulating type thermal incinerators and RCO devices, heat accumulating type catalytic incinerators for purifying and treating industrial and civil organic waste gas. At present, the honeycomb ceramic heat accumulator (hereinafter referred to as ceramic) has been widely used in the fields of steel, mine, machinery, petroleum, chemical industry, medicine, automobile, building material, non-ferrous metal smelting, civil use and the like due to the dual functions of energy conservation and environmental protection. In the RTO device, organic waste gas is heated, burned and purified in a combustor through natural gas, the temperature is generally about 800-.

As long as the production is carried out and the environmental protection is discharged after reaching the standard, the RTO (remote terminal oxidation) device (RCO) device is generally required to continuously carry out instantaneous cold-heat cycle exchange of one cold and one heat 24 hours a day for a long time, which has high requirement on the thermal shock resistance of ceramics. In long-term practical application, the 150 × 150 × 150 (200, 300) ceramic is found to crack after being used for a period of time, and then the ceramic is continuously expanded until the ceramic is cracked and collapsed to block ceramic channels, so that the gas flow is not smooth, the energy consumption is increased, the waste gas purification is incomplete, and particularly, the thermal shock to the ceramic is more severe in some devices with special high heat value and large amount of corrosive gas or treated waste gas. In severe cases, for months, the ceramic fractures and collapses to block the gas flow passages, and the plant has to be shut down without a production overhaul period. After the RTO (RCO) device is shut down, waste gas generated by chemical, pharmaceutical, mechanical and electronic production lines cannot be purified and discharged, the ceramic has to be replaced in the whole production line, the production stop time is generally about one week or even longer, and great economic loss is caused to a factory.

As is known, the damage of the ceramic is mainly caused by the continuous instantaneous cyclic reciprocating thermal expansion and cold contraction to generate micro cracks inside the ceramic, the cracks continuously extend and expand until the ceramic is cracked, collapsed and blocked to cause failure, and the thermal shock resistance of the ceramic is required to be improved as much as possible. The current approaches for improving the thermal shock resistance are as follows: firstly, the material with low thermal expansion coefficient is used, the expansion rate of the material when the material expands with heat and contracts with cold is reduced as much as possible, but the high-temperature material with low thermal expansion coefficient is mainly cordierite or mullite-cordierite synthetic material, but the two materials have the defects of low density, light weight, low heat storage capacity, loose texture, more and large surface pores, easy corrosion by gases such as acid and alkali, performance attenuation caused by the corrosion, easy impurity adsorption and pore channel blockage, low refractoriness, more complex process compared with the use of mullite and high-aluminum material, and higher cost. As a heat storage material, the heat storage capacity, the corrosion resistance and the difficult blockage are the most important performance indexes, and the cost is required to be as low as possible, so that at present, two materials of cordierite or mullite-cordierite are used less in a heat storage body, and two heavier materials of mullite and high alumina are generally used. The heat storage capacity of the two materials can meet the requirements, and the defects are that the thermal expansion coefficient is large, the materials are easy to crack, and the service life of the materials is seriously influenced. Through long-term observation of the process and the characters of ceramic cracking → collapsing → blocking, the ceramic is found to start to crack from the transverse middle waist block and/or longitudinally half-and-half after being used for a period of time, and particularly under the working conditions that the temperature changes violently or the gas contains high-heat value components to generate deflagration, the ceramic is cracked → cracked shortly after being used → cracked → collapsed → blocking the pore channel to cause the equipment to work normally, and the 300-high-ceramic middle fracture is particularly serious. We know that when ceramic pug is in the vacuum pugging and is extruded in the feed cylinder, because its pressure all is along the feed cylinder, the extrusion of a mud outlet and a mould direction, the inside granule of pottery can produce the directional arrangement along extruding the direction, this kind of directional arrangement can cause the serious unbalance of pottery all directions atress, and inner structure and density are serious inhomogeneous to there is great harmful internal stress at the inside production of ceramic body, including the appearance of pottery again is the square, the cuboid is many, stress is difficult for releasing and offset. When the heat accumulator is used as a heat accumulator, the heat exchange is continuously and instantaneously carried out for a long time, the heat expansion and the cold contraction are continuously carried out, and the harmful internal stress is continuously released. Because the stress in all directions of the ceramic is not balanced, the ceramic can be cracked and broken from the weak points with two stress concentrations between the longitudinal stress and the transverse stress and can continuously extend to other places until the ceramic is cracked, collapsed and blocked, so that the ceramic cannot be used.

SUMMERY OF THE UTILITY MODEL

To the problem that above-mentioned present pottery in use exists, the utility model discloses a patent application provides a structural design is more reasonable, thermal shock resistance is better, the technology is simpler, the appearance is also very pleasing to the eye high thermal shock resistance's honeycomb ceramic heat accumulator.

The utility model discloses a technical scheme that the problem that the patent application will be solved was taken is: the utility model provides a high thermal shock resistance's honeycomb ceramic heat accumulator, it includes the body, be provided with a plurality of honeycomb pore ways of arranging according to the law that run through upper and lower two sides in the body, be provided with a plurality of expansion joints that are linked together with honeycomb pore way in the body on the lateral surface of body along honeycomb pore way axis direction, the expansion joint includes one or several kinds in horizontal expansion joint, vertical expansion joint, the slant expansion joint.

Furthermore, the cross sections of the transverse expansion joint, the longitudinal expansion joint and the oblique expansion joint are in any shapes such as rectangle, trapezoid, arc or triangle.

The utility model discloses an advantage is: compared with the prior art, the expansion joints in various forms communicated with the honeycomb duct are arranged on the outer side of the ceramic, so that the ceramic has a buffer room for expansion with heat and contraction with cold during heat exchange, the thermal shock resistance is greatly improved and far exceeds the national standard level, and the shutdown of RTO (remote thermal oxidizer) equipment caused by cracking, cracking and collapse of the ceramic when the production of a factory is in tension is avoided, so that the economic loss caused by the fact that the production line is stopped for dozens of days and the ceramic is replaced due to the fact that the production line does not reach the overhaul period is solved.

Drawings

Figure 1 is a schematic structural diagram of the present invention,

figure 2 is another structure diagram of the utility model,

FIG. 3 is a schematic sectional view A-A of FIG. 1,

FIG. 4 is a schematic view of a structure of a section B-B of FIG. 1,

figure 5 is another schematic view of the structure of section B-B of figure 1,

fig. 6 is various structural schematic diagrams of the transverse expansion joint of the invention.

In the figure, 1, a body 2, honeycomb ducts 3, transverse expansion joints 4, longitudinal expansion joints 5 and oblique expansion joints.

Detailed Description

In order to make the technical solutions of the present invention better understood by those skilled in the art, the present invention is further described in detail below with reference to the accompanying drawings and specific embodiments.

As shown in the figure, the honeycomb ceramic heat accumulator with high thermal shock resistance comprises a body 1, the body is generally square or cuboid, the end face is in the form of a plane, a single groove, four feet or oblique feet, a plurality of honeycomb ducts 2 which penetrate through the upper and lower faces and are regularly arranged are arranged in the body, a plurality of expansion joints (which can also be communicated with a second row of honeycomb ducts from outside to inside) communicated with the outermost honeycomb ducts (from outside to inside) in the body are arranged on the outer side face of the body along the axis direction of the honeycomb ducts (namely on the outer side faces except the upper and lower end faces), the expansion joints comprise one or a combination of a transverse expansion joint 3, a longitudinal expansion joint 4 and an oblique expansion joint 5, the expansion joints are transverse expansion joints and longitudinal expansion joints which are mutually crossed and vertical, and the cross sections of the transverse expansion joints, the longitudinal expansion joints and the oblique expansion joints are rectangular, Trapezoidal, circular or triangular, the expansion gap typically having a width and depth of 2-3 mm or other reasonable width and depth, and the expansion gap typically having a length extending from one side to another parallel side.

In view of this, we produced a batch of ceramics by trial and error using the same batch of mullite or alumina material in the same process, and some of the ceramics were subjected to batch forming and firing with one or more expansion gaps having a width of about 2 mm in the transverse and vertical directions on the four sides in the vertical and parallel honeycomb cell directions before firing, together with ordinary ceramics having no expansion gaps, and then subjected to a thermal shock resistance comparison test at the same time. Ordinary ceramics without expansion gaps can not crack only through 300-degree air cooling (cooling in air) three times of circulation required by national standards, water cooling (quenching in water) can crack or crack respectively twice, and ceramics with expansion gaps can not crack after being cooled for ten to twenty times at 400-degree or above. As the water cooling and air cooling are known to have severe test conditions, the thermal shock resistance of the ceramic with expansion joints is proved to be far higher than the national standard level and far better than that of the common ceramic without expansion joints. The ceramic thermal shock resistance is the most important performance related to the safe operation and the service life of an RTO (regenerative thermal oxidizer) (RCO) device, the purification and standard emission of polluted waste gas and the normal operation of a factory production line. Research on cracking, cracking and breaking failure mechanisms of RTO (RCO) device ceramics in use proves that: the thermal shock resistance of the ceramic with the expansion joint is improved by times compared with the requirement of national standard, the service life of the ceramic is predicted to be improved by times, and the problem that RTO (remote terminal oxidation) equipment is shut down due to cracking, breaking, collapsing and blocking of the ceramic when the production of a factory is in tension can be avoided, so that the economic loss caused by replacing the ceramic after the production line is shut down for dozens of days is solved. Therefore, the service life of the ceramic with the expansion joint is greatly prolonged on the premise of basically not increasing the cost, and the ceramic has immeasurable economic benefit and social benefit. Have been used in many RTO devices for a long time without cracking.

Meanwhile, compared with the inclined expansion joint which is only provided with the vertical expansion joint or the transverse expansion joint which is not vertical and is crossed at any inclination, the vertical expansion joint and the transverse expansion joint which are vertical to each other are arranged in the longitudinal direction and the transverse direction, the design of the vertical expansion joint is more reasonable, the thermal shock resistance is better, the process is simpler, the appearance is more attractive, and the vertical expansion joint and the transverse expansion joint are generally selected. 150 x 150 and 150 x 200 are generally parallel and perpendicular to the direction of the pore canal, the central division of the four sides of the 150 x 300 ceramic can be provided with the cross expansion joint which is perpendicular to each other, but the central division of the four sides of the 150 x 300 ceramic in the direction of the pore canal is provided with one joint every 75 mm, the four sides of the ceramic in the direction of the pore canal are provided with one joint (three parallel expansion joints in total), the thermal shock resistance is better, and the specific expansion joint number and distribution form can be selected according to the requirements of customers or actual working conditions.

The above embodiments are only used for illustrating the technical solutions of the present invention and not for limiting, although the present invention has been described in detail with reference to the specific embodiments, those skilled in the art should understand that the technical solutions of the present invention can be modified or replaced with equivalents without departing from the spirit and scope of the technical solutions of the present invention, which should be covered in the scope of the claims of the present invention.

Claims (3)

1. A honeycomb ceramic heat accumulator with high thermal shock resistance is characterized in that: the honeycomb expansion joint comprises a body (1), a plurality of honeycomb pore passages (2) which run through the upper surface and the lower surface and are regularly arranged are arranged in the body, a plurality of expansion joints communicated with the honeycomb pore passages in the body are arranged on the outer side surface of the body along the axis of the honeycomb pore passages, and each expansion joint comprises one or more of a transverse expansion joint (3), a longitudinal expansion joint (4) and an oblique expansion joint (5).

2. The high thermal shock resistance honeycomb ceramic heat accumulator according to claim 1, wherein: the cross sections of the transverse expansion joint (3), the longitudinal expansion joint (4) and the oblique expansion joint (5) are rectangular, trapezoidal, circular arc or triangular.

3. The high thermal shock resistance honeycomb ceramic heat accumulator according to claim 1 or 2, wherein: the transverse expansion joint (3), the longitudinal expansion joint (4) and the oblique expansion joint (5) are communicated with a first row of honeycomb pore passages from outside to inside in the body.

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