Industry | Technical progress of thermal insulation coatings

Abstract: Thermal insulation coatings can effectively improve the energy-saving effect of equipment and pipelines, reduce energy consumption, and have good application prospects in the petrochemical industry.

75em; text-indent: 2em; font-family: ; font-size: 16px; box-sizing: border-box; -webkit-tap-highlight-color: rgba(0, 0, 0, 0);">In the petrochemical industry, the annual energy loss due to pipe heat dissipation accounts for about one-third of the total energy consumption, and the corrosion of petrochemical pipes also brings many safety hazards to its production and operation.

75em; text-indent: 2em; font-family: ; font-size: 16px; box-sizing: border-box; -webkit-tap-highlight-color: rgba(0, 0, 0, 0);">At present, domestic refining and chemical enterprises usually use traditional porous rock wool, aluminum silicate roll felt, etc.

75em; text-indent: 2em; font-family: ; font-size: 16px; box-sizing: border-box; -webkit-tap-highlight-color: rgba(0, 0, 0, 0);">The thermal insulation coating developed in recent years is a new type of functional coating that starts from the heat transfer mechanism and reduces the heat transfer in the substrate in a targeted manner.

75em; text-indent: 2em; font-family: ; font-size: 16px; box-sizing: border-box; -webkit-tap-highlight-color: rgba(0, 0, 0, 0);">1 Thermal insulation coating

75em; text-indent: 2em; font-family: ; font-size: 16px; box-sizing: border-box; -webkit-tap-highlight-color: rgba(0, 0, 0, 0);">In the field of thermal insulation coatings, the thermal insulation performance of the coating is mainly achieved through mechanisms such as increasing the degree of thermal radiation reflection of the coating, enhancing the emissivity of the thermal radiation of the coating, and slowing down the thermal conduction of the coating.

75em; text-indent: 2em; font-family: ; font-size: 16px; box-sizing: border-box; -webkit-tap-highlight-color: rgba(0, 0, 0, 0);">1.

75em; text-indent: 2em; font-family: ; font-size: 16px; box-sizing: border-box; -webkit-tap-highlight-color: rgba(0, 0, 0, 0);">Reflective thermal insulation coatings are coatings that have high reflectivity to heat radiation (solar radiation, infrared radiation, etc.

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75em; text-indent: 2em; font-family: ; font-size: 16px; box-sizing: border-box; -webkit-tap-highlight-color: rgba(0, 0, 0, 0);">Pigments and fillers are the key to ensure that the reflective insulation coating has high reflectivity to solar radiation.

75em; text-indent: 2em; font-family: ; font-size: 16px; box-sizing: border-box; -webkit-tap-highlight-color: rgba(0, 0, 0, 0);">With the development of economy, people are more inclined to paint with rich colors.

75em; text-indent: 2em; font-family: ; font-size: 16px; box-sizing: border-box; -webkit-tap-highlight-color: rgba(0, 0, 0, 0);">In terms of coating durability, since reflective thermal insulation coatings are mainly used to reflect solar radiation, the current film-forming resins of the coatings are mainly polymers with excellent UV aging resistance such as acrylic resins and fluorine-containing resins.

75em; text-indent: 2em; font-family: ; font-size: 16px; box-sizing: border-box; -webkit-tap-highlight-color: rgba(0, 0, 0, 0);">However, the reflective thermal insulation coating is only a material that reflects heat radiation, and it cannot hinder the heat transfer of the other two heat transfer methods to the substrate.

75em; text-indent: 2em; font-family: ; font-size: 16px; box-sizing: border-box; -webkit-tap-highlight-color: rgba(0, 0, 0, 0);">1.

75em; text-indent: 2em; font-family: ; font-size: 16px; box-sizing: border-box; -webkit-tap-highlight-color: rgba(0, 0, 0, 0);">Radiant thermal insulation coating is a coating that actively reduces the heat transfer of the substrate in the form of emitting heat radiation.

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75em; text-indent: 2em; font-family: ; font-size: 16px; box-sizing: border-box; -webkit-tap-highlight-color: rgba(0, 0, 0, 0);">Radiant fillers mainly include SiC, cordierite (main component is Mg2Al4Si5O18; may contain Na, K, Ca , Fe, Mn and other elements), transition metal oxides (such as MnO2, Cr2O3, CoO, CuO) and other materials, which absorb heat Later, through the energy of molecular vibration and rotation, the crystal lattice and bond clusters are continuously collided, and the absorbed heat is re-emitted back to the environment.

75em; text-indent: 2em; font-family: ; font-size: 16px; box-sizing: border-box; -webkit-tap-highlight-color: rgba(0, 0, 0, 0);">In addition, the excellent thermal insulation effect of the radiant thermal insulation coating can also play a very good protective effect on the substrate.

75em; text-indent: 2em; font-family: ; font-size: 16px; box-sizing: border-box; -webkit-tap-highlight-color: rgba(0, 0, 0, 0);">At present, radiant thermal insulation coatings are mainly ceramic coatings, the coatings need to be sintered and formed, and the construction process is complicated; and the ceramic coating is a brittle material, and its fracture work is generally only about 300 J/m2, due to the brittleness of the coating The main failure mode is the failure of the coating.

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3  Barrier type thermal insulation coating

75em; text-indent: 2em; font-family: ; font-size: 16px; box-sizing: border-box; -webkit-tap-highlight-color: rgba(0, 0, 0, 0);">Barrier-type thermal insulation coating is a coating whose main purpose is to reduce the internal heat conduction of the coating.
It is based on the principle that the conduction rate of heat in the air is much lower than the conduction rate of solid materials.
, Functional fillers with low thermal conductivity (such as hollow glass beads , expanded pearl powder, silicon aerogel, etc.
) are mixed into the coating system to reduce the thermal conductivity of the coating and achieve the purpose of heat insulation (Figure 3) ).

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75em; text-indent: 2em; font-family: ; font-size: 16px; box-sizing: border-box; -webkit-tap-highlight-color: rgba(0, 0, 0, 0);">When the heat in the environment is transferred to the surface of the substrate through conduction, radiation, and convection, the heat transfer from the surface of the substrate to the interior is mainly realized through heat conduction.
Barrier-type thermal insulation coatings add high porosity fillers to the coating system to force heat to conduct through the air in the coating pores, thereby greatly reducing the thermal conductivity of the coating.
If the diameter of the pores of the barrier-type filler is small enough (as small as nanometers), the air molecules inside cannot convection, nor can it perform thermal movement like ordinary still air.
Such pores are actually equivalent to a vacuum state.
In this case The thermal conductivity of the barrier filler can even be lower than that of ordinary air (such as silicon aerogel, fiber aerogel, etc.
).
Adding the above-mentioned pigments and fillers to the coating system, the coating will have excellent thermal insulation performance.

75em; text-indent: 2em; font-family: ; font-size: 16px; box-sizing: border-box; -webkit-tap-highlight-color: rgba(0, 0, 0, 0);">Obviously, the thermal insulation mechanism of the barrier type thermal insulation coating is suitable for any environment that requires thermal insulation.
At present, it has corresponding applications in ambient to high temperature environments.
In the petrochemical industry, according to the temperature of the coating service environment, it can generally be divided into "low temperature" working conditions (normal temperature to 200°C) and high temperature working conditions (200~500°C) thermal insulation coatings.

75em; text-indent: 2em; font-family: ; font-size: 16px; box-sizing: border-box; -webkit-tap-highlight-color: rgba(0, 0, 0, 0);">The design of barrier-type thermal insulation coatings for service under "low temperature" conditions is relatively simple.
As long as the barrier-type filler is effectively dispersed in a suitable matrix resin, it can be successfully prepared.
At present, a large number of barrier-type thermal insulation coatings have been successfully developed and applied accordingly.
In terms of the thermal insulation performance of the coating, the application of new thermal insulation fillers in recent years has greatly improved the thermal insulation performance of the coating.
For example, the thermal conductivity of silicon aerogel is significantly lower than that of other traditional hollow thermal insulation fillers, even as low as 0.
013 W/ (M·K); and the successful preparation of hollow reflective heat-insulating fillers such as hollow TiO2 and TiO2 coated hollow glass beads also makes the coating combine the advantages of barrier and reflective heat-insulating coatings.
The research and application of barrier thermal insulation coatings under "low temperature" working conditions are relatively mature, but there is still room for research and development in the direction of how to further reduce the thermal conductivity of the coating, how to improve the overall performance of the coating, and how to prepare environmentally friendly coatings.
.

75em; text-indent: 2em; font-family: ; font-size: 16px; box-sizing: border-box; -webkit-tap-highlight-color: rgba(0, 0, 0, 0);">For high temperature conditions, the heat resistance of the matrix material is a key issue.
Inorganic silicate coatings have been popularized since the 1980s.
They are inorganic coatings based on cement and expanded perlite as aggregate.
Obviously, although this kind of coating can meet the requirements of high temperature working conditions with its heat resistance, its adhesion and corrosion resistance are far less than those based on organic materials.
In contrast, as a new type of high-performance inorganic material, geopolymer has a polymer-like bonding structure.
While the material maintains the excellent heat resistance of inorganic materials, its adhesion and corrosion resistance have been greatly improved.
Improvement.
The preparation of new inorganic barrier type anticorrosive and thermal insulation coatings based on geopolymers has good development prospects.
In terms of organic materials as the base material, silicone resin is a typical organic material with excellent heat resistance, and is currently an important direction for the preparation of thermal insulation coatings under high temperature conditions.
Under normal circumstances, it can have a good use effect at 300~400 ℃, but the adhesion between the silicone resin and the substrate is often poor.
Under higher temperature conditions, the silicone resin is used as the base material.
Thermal insulation coatings need to be further developed.

75em; text-indent: 2em; font-family: ; font-size: 16px; box-sizing: border-box; -webkit-tap-highlight-color: rgba(0, 0, 0, 0);">2 Anti-corrosion and heat insulation integrated coating

75em; text-indent: 2em; font-family: ; font-size: 16px; box-sizing: border-box; -webkit-tap-highlight-color: rgba(0, 0, 0, 0);">Reflective thermal insulation coating is only a material that reflects heat radiation.
It cannot hinder the heat transfer of the other two heat transfer methods to the substrate, so it cannot directly insulate the high-temperature heat transfer medium.
Radiation-type thermal insulation coatings have higher thermal insulation efficiency in high-temperature environments, but the thermal insulation effects in other temperature sections are not good, and there are still certain problems in coating performance and film forming methods of this type of coating.
In contrast, barrier-type thermal insulation coatings can play a good role in thermal insulation at any temperature range.
This type of coating can meet the thermal insulation requirements of storage tanks, pipelines, boilers and other facilities according to different working conditions, and has a good development prospect.
However, in the petrochemical industry, in addition to the serious economic losses and safety hazards caused by heat loss to the refining and chemical enterprises, the corrosion problems of equipment and pipelines also need to be solved urgently.
The corrosion resistance of ordinary reflective, radiant, and barrier thermal insulation coatings is often insufficient, and the service life of the coating is not good in harsh corrosive environments such as refineries.
Therefore, on the basis of the barrier type thermal insulation coating, the corrosion resistance of the coating is further improved, and the preparation of an integrated anticorrosive thermal insulation coating has good economic benefits and development value.

75em; text-indent: 2em; font-family: ; font-size: 16px; box-sizing: border-box; -webkit-tap-highlight-color: rgba(0, 0, 0, 0);">At present, the barrier type thermal insulation coating with acrylic resin as the matrix resin has good UV aging resistance and weather resistance, and is generally only applied to the thermal insulation of the outer wall of the building.
However, in a severely corrosive environment, this type of coating also needs to be used in conjunction with a heavy-duty anti-corrosion coating.
And an epoxy resin having excellent adhesion and corrosion resistance, with its insulation coating is a matrix resin may be applied to corrosion in harsh environments.
However, the heat resistance of the above two types of coatings is often insufficient, and it is difficult to meet the requirements of "low temperature" working conditions (normal temperature to 200°C) in the petrochemical industry.

75em; text-indent: 2em; font-family: ; font-size: 16px; box-sizing: border-box; -webkit-tap-highlight-color: rgba(0, 0, 0, 0);">Therefore, on the basis of the above research, South China University of Technology has prepared a solvent- free anticorrosive, thermal insulation integrated coating TI-200 for the petrochemical industry in response to the "low temperature" operating conditions in the petrochemical industry .
The coating uses glycidylamine epoxy resin with both heat resistance and corrosion resistance as the matrix resin, and is compounded with hollow glass beads with excellent heat insulation performance and glass flakes with excellent corrosion resistance.
The results show that the thermal conductivity of the coating can be as low as 0.
136W/(m·K); field simulation experiments have shown that petrochemical pipelines with a pipe temperature of 180℃ only need to be painted with 4mm thick TI-200, and the temperature outside the pipe is only It can be lowered to 80°C, and the coating has good thermal insulation properties.
Moreover, the coating can remain stable for a long time at 200°C, without discoloration, cracking, peeling, peeling, etc.
(Figure 4).

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75em; text-indent: 2em; font-family: ; font-size: 16px; box-sizing: border-box; -webkit-tap-highlight-color: rgba(0, 0, 0, 0);">In addition, the VOCs of the coating are only 51.
5g/L, and the coating has excellent mechanical properties and corrosion resistance.
It can effectively resist acid, alkali, salt and other corrosion, and meets the petrochemical industry standard SH/T3022—2011 "Petrochemical Equipment and Piping "Coating Anti-corrosion Design Code" has technical requirements for epoxy intermediate paint (Table 1).

75em; text-indent: 2em; font-family: ; font-size: 16px; box-sizing: border-box; -webkit-tap-highlight-color: rgba(0, 0, 0, 0);">Table 1 Coating performance of TI-200

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75em; text-indent: 2em; font-family: ; font-size: 16px; box-sizing: border-box; -webkit-tap-highlight-color: rgba(0, 0, 0, 0);">In order to solve the problems of insufficient adhesion, corrosion resistance and insufficient heat resistance of epoxy resin in traditional high-temperature resistant silicone coatings, silicone modified epoxy resin is used as the matrix resin, which can be combined with silicone resin and epoxy resin.
Advantages, good heat resistance, corrosion resistance and adhesion.
The obtained coating can exist stably at 200-400°C, and has good coating properties, corrosion resistance and heat preservation properties.
In addition, low-temperature melting glass powder is compounded in the coating.
When the temperature is too high, the low-temperature molten glass powder gradually melts and interacts with the Si-O-Si main chain of the epoxy-modified silicone resin to re-form a film to form a new high-temperature resistant silicide layer (Figure 5).

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75em; text-indent: 2em; font-family: ; font-size: 16px; box-sizing: border-box; -webkit-tap-highlight-color: rgba(0, 0, 0, 0);">In other words, the coating undergoes a "secondary film formation" process to further ensure its performance in all aspects under working conditions above 400 ℃ (Figure 6).

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75em; text-indent: 2em; font-family: ; font-size: 16px; box-sizing: border-box; -webkit-tap-highlight-color: rgba(0, 0, 0, 0);">The final coating still has good durability at a high temperature of 500°C, and the thermal conductivity of the coating is as low as 0.
138W/(m·K).
The coating performance meets the requirements of the standard HG/T3362-2003 (Table 2), which effectively solves the problems of anti-corrosion and heat preservation of petrochemical pipelines under high temperature conditions.

75em; text-indent: 2em; font-family: ; font-size: 16px; box-sizing: border-box; -webkit-tap-highlight-color: rgba(0, 0, 0, 0);">Table 2 Coating performance of TI-500

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75em; text-indent: 2em; font-family: ; font-size: 16px; box-sizing: border-box; -webkit-tap-highlight-color: rgba(0, 0, 0, 0);">3 Conclusion

75em; text-indent: 2em; font-family: ; font-size: 16px; box-sizing: border-box; -webkit-tap-highlight-color: rgba(0, 0, 0, 0);">Compared with traditional thermal insulation materials, thermal insulation coatings have the characteristics of high efficiency, simplicity, safety, and low price, and have good application prospects in the petrochemical industry.

75em; text-indent: 2em; font-family: ; font-size: 16px; box-sizing: border-box; -webkit-tap-highlight-color: rgba(0, 0, 0, 0);">(1) Reflective thermal insulation coatings have high reflectivity to heat radiation and can effectively prevent buildings from absorbing solar radiation.
They have been widely used in thermal insulation of building exterior walls.
In severely corrosive environments such as petrochemical storage tanks, reflective thermal insulation coatings and heavy-duty anti-corrosion coatings are matched to make the coating system have both anti-corrosion and thermal insulation properties.
However, the reflective thermal insulation coating is only a material that reflects heat radiation.
It cannot hinder the heat transfer of the other two heat transfer methods to the substrate, so it cannot directly insulate the high temperature heat transfer medium.

75em; text-indent: 2em; font-family: ; font-size: 16px; box-sizing: border-box; -webkit-tap-highlight-color: rgba(0, 0, 0, 0);">(2) The radiant thermal insulation coating actively reduces the heat conduction on the surface of the substrate by emitting heat radiation, and has higher thermal insulation efficiency in high-temperature environments, and is suitable for thermal insulation of high-temperature petrochemical pipelines, boilers and other facilities.
Generally, radiant thermal insulation coatings based on ceramic coatings have excellent thermal stability.
In high temperature environments, it has a good protective effect on the substrate.
However, the poor thermal insulation effect of other temperature sections and the brittle cracking of the ceramic coating limit its application.

75em; text-indent: 2em; font-family: ; font-size: 16px; box-sizing: border-box; -webkit-tap-highlight-color: rgba(0, 0, 0, 0);">(3) The barrier type thermal insulation coating can directly block the heat conduction on the surface of the substrate, and can play a good thermal insulation effect at any temperature range.
In the petrochemical industry, barrier-type thermal insulation coatings can meet the thermal insulation requirements of storage tanks, pipelines, boilers and other facilities according to different working conditions.

75em; text-indent: 2em; font-family: ; font-size: 16px; box-sizing: border-box; -webkit-tap-highlight-color: rgba(0, 0, 0, 0);">(4) However, the current thermal insulation coatings have insufficient corrosion resistance, and the service life of the coatings is not good in a severely corrosive environment.
The anti-corrosion and thermal insulation integrated coating developed on the basis of the barrier type thermal insulation coating can not only effectively reduce the heat loss, but also greatly slow down the corrosion rate of the substrate, and has good economic benefits and development value.

75em; text-indent: 2em; font-family: ; font-size: 16px; box-sizing: border-box; -webkit-tap-highlight-color: rgba(0, 0, 0, 0);">Preface

75em; text-indent: 2em; font-family: ; font-size: 16px; box-sizing: border-box; -webkit-tap-highlight-color: rgba(0, 0, 0, 0);">Preface

75em; text-indent: 2em; font-family: ; font-size: 16px; box-sizing: border-box; -webkit-tap-highlight-color: rgba(0, 0, 0, 0);">Preface

Foreword Preface

75em; text-indent: 2em; font-family: ; font-size: 16px; box-sizing: border-box; -webkit-tap-highlight-color: rgba(0, 0, 0, 0);">In the petrochemical industry, the annual energy loss due to pipe heat dissipation accounts for about one-third of the total energy consumption, and the corrosion of petrochemical pipes also brings many safety hazards to its production and operation.
Therefore, anti-corrosion and heat preservation are very important for the petrochemical industry.

75em; text-indent: 2em; font-family: ; font-size: 16px; box-sizing: border-box; -webkit-tap-highlight-color: rgba(0, 0, 0, 0);">At present, domestic refining and chemical enterprises usually use traditional porous rock wool, aluminum silicate roll felt, etc.
to heat insulation equipment and pipelines.
Generally, the thickness of the insulation layer can reach 100~200 mm, the construction process is complicated and the cost is high; and it is thick and thick.
The thermal insulation layer will also cover up the damage of equipment and pipelines, making it difficult for petrochemical companies to avoid conventional production risks and safety hazards.
At the same time, the structure of the insulation layer of elbows, tees, valves and other special-shaped parts is complex, with many connections and extremely difficult construction.
These parts are often exposed, which is a weak link in the insulation of equipment and pipelines.
In particular, traditional porous thermal insulation materials often do not have anti-corrosion properties.
Corrosion factors can easily adhere and be stored in their pores and become a heat conduction medium, which not only greatly reduces the thermal insulation efficiency of equipment and pipelines, but also shortens The service life of the entire insulation system.

75em; text-indent: 2em; font-family: ; font-size: 16px; box-sizing: border-box; -webkit-tap-highlight-color: rgba(0, 0, 0, 0);">The thermal insulation coating developed in recent years is a new type of functional coating that starts from the heat transfer mechanism and reduces the heat transfer in the substrate in a targeted manner.
Compared with traditional thermal insulation materials, thermal insulation coatings have excellent thermal insulation effects.
The thickness of a few millimeters can achieve the thermal insulation effect of traditional thermal insulation layers of 100~200 mm; therefore, the damage of equipment and pipelines can also be easily detected and system maintenance Difficulty and maintenance costs have also dropped significantly.
In addition, the coating construction process is simple, which can achieve full coverage of special-shaped parts such as elbows, tees, valves, etc.
, and effectively reduce the heat dissipation of the pipeline.
In particular, through the reasonable selection of film-forming materials and optimization of the formula, the coating can also have high permeability resistance and corrosion resistance, effectively avoiding the penetration of corrosive factors in the coating, and greatly slowing down the corrosion rate of equipment and insulation systems.
Improve its service life.
Thermal insulation coatings provide a new strategy for the petrochemical industry to save energy, reduce emissions, and extend pipeline life.
This article summarizes the progress of thermal insulation coatings and looks forward to its development trends.

75em; text-indent: 2em; font-family: ; font-size: 16px; box-sizing: border-box; -webkit-tap-highlight-color: rgba(0, 0, 0, 0);">In the petrochemical industry, the annual energy loss due to pipe heat dissipation accounts for about one-third of the total energy consumption, and the corrosion of petrochemical pipes also brings many safety hazards to its production and operation.
Therefore, anti-corrosion and heat preservation are very important for the petrochemical industry.

In the petrochemical industry, the annual energy loss due to pipe heat dissipation accounts for about one-third of the total energy consumption, and the corrosion of petrochemical pipes also brings many safety hazards to its production and operation.
Therefore, anti-corrosion and heat preservation are very important for the petrochemical industry.

75em; text-indent: 2em; font-family: ; font-size: 16px; box-sizing: border-box; -webkit-tap-highlight-color: rgba(0, 0, 0, 0);">At present, domestic refining and chemical enterprises usually use traditional porous rock wool, aluminum silicate roll felt, etc.
to heat insulation equipment and pipelines.
Generally, the thickness of the insulation layer can reach 100~200 mm, the construction process is complicated and the cost is high; and it is thick and thick.
The thermal insulation layer will also cover up the damage of equipment and pipelines, making it difficult for petrochemical companies to avoid conventional production risks and safety hazards.
At the same time, the structure of the insulation layer of elbows, tees, valves and other special-shaped parts is complex, with many connections and extremely difficult construction.
These parts are often exposed, which is a weak link in the insulation of equipment and pipelines.
In particular, traditional porous thermal insulation materials often do not have anti-corrosion properties.
Corrosion factors can easily adhere and be stored in their pores and become a heat conduction medium, which not only greatly reduces the thermal insulation efficiency of equipment and pipelines, but also shortens The service life of the entire insulation system.

At present, domestic refining and chemical enterprises usually use traditional porous rock wool, aluminum silicate roll felt, etc.
to heat insulation equipment and pipelines.
Generally, the thickness of the insulation layer can reach 100~200 mm, the construction process is complicated and the cost is high; and it is thick and thick.
The thermal insulation layer will also cover up the damage of equipment and pipelines, making it difficult for petrochemical companies to avoid conventional production risks and safety hazards.
At the same time, the structure of the insulation layer of elbows, tees, valves and other special-shaped parts is complex, with many connections and extremely difficult construction.
These parts are often exposed, which is a weak link in the insulation of equipment and pipelines.
In particular, traditional porous thermal insulation materials often do not have anti-corrosion properties.
Corrosion factors can easily adhere and be stored in their pores and become a heat conduction medium, which not only greatly reduces the thermal insulation efficiency of equipment and pipelines, but also shortens The service life of the entire insulation system.

75em; text-indent: 2em; font-family: ; font-size: 16px; box-sizing: border-box; -webkit-tap-highlight-color: rgba(0, 0, 0, 0);">The thermal insulation coating developed in recent years is a new type of functional coating that starts from the heat transfer mechanism and reduces the heat transfer in the substrate in a targeted manner.
Compared with traditional thermal insulation materials, thermal insulation coatings have excellent thermal insulation effects.
The thickness of a few millimeters can achieve the thermal insulation effect of traditional thermal insulation layers of 100~200 mm; therefore, the damage of equipment and pipelines can also be easily detected and system maintenance Difficulty and maintenance costs have also dropped significantly.
In addition, the coating construction process is simple, which can achieve full coverage of special-shaped parts such as elbows, tees, valves, etc.
, and effectively reduce the heat dissipation of the pipeline.
In particular, through the reasonable selection of film-forming materials and optimization of the formula, the coating can also have high permeability resistance and corrosion resistance, effectively avoiding the penetration of corrosive factors in the coating, and greatly slowing down the corrosion rate of equipment and insulation systems.
Improve its service life.
Thermal insulation coatings provide a new strategy for the petrochemical industry to save energy, reduce emissions, and extend pipeline life.
This article summarizes the progress of thermal insulation coatings and looks forward to its development trends.

The thermal insulation coating developed in recent years is a new type of functional coating that starts from the heat transfer mechanism and reduces the heat transfer in the substrate in a targeted manner.
Compared with traditional thermal insulation materials, thermal insulation coatings have excellent thermal insulation effects.
The thickness of a few millimeters can achieve the thermal insulation effect of traditional thermal insulation layers of 100~200 mm; therefore, the damage of equipment and pipelines can also be easily detected and system maintenance Difficulty and maintenance costs have also dropped significantly.
In addition, the coating construction process is simple, which can achieve full coverage of special-shaped parts such as elbows, tees, valves, etc.
, and effectively reduce the heat dissipation of the pipeline.
In particular, through the reasonable selection of film-forming materials and optimization of the formula, the coating can also have high permeability resistance and corrosion resistance, effectively avoiding the penetration of corrosive factors in the coating, and greatly slowing down the corrosion rate of equipment and insulation systems.
Improve its service life.
Thermal insulation coatings provide a new strategy for the petrochemical industry to save energy, reduce emissions, and extend pipeline life.
This article summarizes the progress of thermal insulation coatings and looks forward to its development trends.

75em; text-indent: 2em; font-family: ; font-size: 16px; box-sizing: border-box; -webkit-tap-highlight-color: rgba(0, 0, 0, 0);">1 Thermal insulation coating

75em; text-indent: 2em; font-family: ; font-size: 16px; box-sizing: border-box; -webkit-tap-highlight-color: rgba(0, 0, 0, 0);">1 Thermal insulation coating

75em; text-indent: 2em; font-family: ; font-size: 16px; box-sizing: border-box; -webkit-tap-highlight-color: rgba(0, 0, 0, 0);">1 Thermal insulation coating

1 Thermal insulation coating 1 Thermal insulation coating

75em; text-indent: 2em; font-family: ; font-size: 16px; box-sizing: border-box; -webkit-tap-highlight-color: rgba(0, 0, 0, 0);">In the field of thermal insulation coatings, the thermal insulation performance of the coating is mainly achieved through mechanisms such as increasing the degree of thermal radiation reflection of the coating, enhancing the emissivity of the thermal radiation of the coating, and slowing down the thermal conduction of the coating.
According to different thermal insulation mechanisms, it can be divided into three types: reflective thermal insulation coatings, radiation thermal insulation coatings and barrier thermal insulation coatings.

75em; text-indent: 2em; font-family: ; font-size: 16px; box-sizing: border-box; -webkit-tap-highlight-color: rgba(0, 0, 0, 0);">In the field of thermal insulation coatings, the thermal insulation performance of the coating is mainly achieved through mechanisms such as increasing the degree of thermal radiation reflection of the coating, enhancing the emissivity of the thermal radiation of the coating, and slowing down the thermal conduction of the coating.
According to different thermal insulation mechanisms, it can be divided into three types: reflective thermal insulation coatings, radiation thermal insulation coatings and barrier thermal insulation coatings.

In the field of thermal insulation coatings, the thermal insulation performance of the coating is mainly achieved through mechanisms such as increasing the degree of thermal radiation reflection of the coating, enhancing the emissivity of the thermal radiation of the coating, and slowing down the thermal conduction of the coating.
According to different thermal insulation mechanisms, it can be divided into three types: reflective thermal insulation coatings, radiation thermal insulation coatings and barrier thermal insulation coatings.

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75em; text-indent: 2em; font-family: ; font-size: 16px; box-sizing: border-box; -webkit-tap-highlight-color: rgba(0, 0, 0, 0);">（、），，（1）。

75em; text-indent: 2em; font-family: ; font-size: 16px; box-sizing: border-box; -webkit-tap-highlight-color: rgba(0, 0, 0, 0);">（、），，（1）。

（、），，（1）。

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75em; text-indent: 2em; font-family: ; font-size: 16px; box-sizing: border-box; -webkit-tap-highlight-color: rgba(0, 0, 0, 0);">。，，。，TiO2、ZnO。80%，95%。，，，，，。，，，。

75em; text-indent: 2em; font-family: ; font-size: 16px; box-sizing: border-box; -webkit-tap-highlight-color: rgba(0, 0, 0, 0);">，。。，，，，。，、，、、。、，、。，，。，。

75em; text-indent: 2em; font-family: ; font-size: 16px; box-sizing: border-box; -webkit-tap-highlight-color: rgba(0, 0, 0, 0);">，，、。、，。，，，。C—F485.
6 kJ/mol，，，C—CF。，。C—F、；、、、；。

75em; text-indent: 2em; font-family: ; font-size: 16px; box-sizing: border-box; -webkit-tap-highlight-color: rgba(0, 0, 0, 0);">，2。（、），。，，，。，，。

75em; text-indent: 2em; font-family: ; font-size: 16px; box-sizing: border-box; -webkit-tap-highlight-color: rgba(0, 0, 0, 0);">。，，。，TiO2、ZnO。80%，95%。，，，，，。，，，。

。，，。，TiO2、ZnO。80%，95%。，，，，，。，，，。

75em; text-indent: 2em; font-family: ; font-size: 16px; box-sizing: border-box; -webkit-tap-highlight-color: rgba(0, 0, 0, 0);">，。。，，，，。，、，、、。、，、。，，。，。

，。。，，，，。，、，、、。、，、。，，。，。

75em; text-indent: 2em; font-family: ; font-size: 16px; box-sizing: border-box; -webkit-tap-highlight-color: rgba(0, 0, 0, 0);">，，、。、，。，，，。C—F485.
6 kJ/mol，，，C—CF。，。C—F、；、、、；。

，，、。、，。，，，。C—F485.
6 kJ/mol，，，C—CF。，。C—F、；、、、；。

75em; text-indent: 2em; font-family: ; font-size: 16px; box-sizing: border-box; -webkit-tap-highlight-color: rgba(0, 0, 0, 0);">，2。（、），。，，，。，，。

，2。（、），。，，，。，，。

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75em; text-indent: 2em; font-family: ; font-size: 16px; box-sizing: border-box; -webkit-tap-highlight-color: rgba(0, 0, 0, 0);">。，。，，（2）。

75em; text-indent: 2em; font-family: ; font-size: 16px; box-sizing: border-box; -webkit-tap-highlight-color: rgba(0, 0, 0, 0);">。，。，，（2）。

。，。，，（2）。

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75em; text-indent: 0em; font-family: ; font-size: 16px; box-sizing: border-box; -webkit-tap-highlight-color: rgba(0, 0, 0, 0);">

75em; text-indent: 2em; font-family: ; font-size: 16px; box-sizing: border-box; -webkit-tap-highlight-color: rgba(0, 0, 0, 0);">SiC、（Mg2Al4Si5O18；Na、K、Ca、Fe、Mn）、（MnO2、Cr2O3、CoO、CuO），，、，、，。，“”。，，，，；，，。，。，。、；、。-(Ste-fan-Boltzmann law)，。，，，，。(Planck's radiation law)，，，，。，。，、，，，“”，。，85%，（Fe2O3-MnO2-CoO-CuO、NiO-Cr2O3-SiC）95%，。，5%~10%，，，。

75em; text-indent: 2em; font-family: ; font-size: 16px; box-sizing: border-box; -webkit-tap-highlight-color: rgba(0, 0, 0, 0);">，。，，1~4；，50%~70%，，。，，，，。，SiC，SiC。、，，，，、。

75em; text-indent: 2em; font-family: ; font-size: 16px; box-sizing: border-box; -webkit-tap-highlight-color: rgba(0, 0, 0, 0);">，，，；，300 J/m2，。，，400 ℃，，；1000℃，，，。，。

75em; text-indent: 2em; font-family: ; font-size: 16px; box-sizing: border-box; -webkit-tap-highlight-color: rgba(0, 0, 0, 0);">SiC、（Mg2Al4Si5O18；Na、K、Ca、Fe、Mn）、（MnO2、Cr2O3、CoO、CuO），，、，、，。，“”。，，，，；，，。，。，。、；、。-(Ste-fan-Boltzmann law)，。，，，，。(Planck's radiation law)，，，，。，。，、，，，“”，。，85%，（Fe2O3-MnO2-CoO-CuO、NiO-Cr2O3-SiC）95%，。，5%~10%，，，。

SiC、（Mg2Al4Si5O18；Na、K、Ca、Fe、Mn）、（MnO2、Cr2O3、CoO、CuO），，、，、，。，“”。，，，，；，，。，。，。、；、。-(Ste-fan-Boltzmann law)，。，，，，。(Planck's radiation law)，，，，。，。，、，，，“”，。，85%，（Fe2O3-MnO2-CoO-CuO、NiO-Cr2O3-SiC）95%，。，5%~10%，，，。

75em; text-indent: 2em; font-family: ; font-size: 16px; box-sizing: border-box; -webkit-tap-highlight-color: rgba(0, 0, 0, 0);">，。，，1~4；，50%~70%，，。，，，，。，SiC，SiC。、，，，，、。

，。，，1~4；，50%~70%，，。，，，，。，SiC，SiC。、，，，，、。

75em; text-indent: 2em; font-family: ; font-size: 16px; box-sizing: border-box; -webkit-tap-highlight-color: rgba(0, 0, 0, 0);">，，，；，300 J/m2，。，，400 ℃，，；1000℃，，，。，。

，，，；，300 J/m2，。，，400 ℃，，；1000℃，，，。，。

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3 

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75em; text-indent: 2em; font-family: ; font-size: 16px; box-sizing: border-box; -webkit-tap-highlight-color: rgba(0, 0, 0, 0);">，，、、（、、），，（3）。

75em; text-indent: 2em; font-family: ; font-size: 16px; box-sizing: border-box; -webkit-tap-highlight-color: rgba(0, 0, 0, 0);">，，、、（、、），，（3）。

，，、、（、、），，（3）。

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75em; text-indent: 2em; font-family: ; font-size: 16px; box-sizing: border-box; -webkit-tap-highlight-color: rgba(0, 0, 0, 0);">、、，。，，。（），，，，（、）。，。

75em; text-indent: 2em; font-family: ; font-size: 16px; box-sizing: border-box; -webkit-tap-highlight-color: rgba(0, 0, 0, 0);">，。，。，，“”（200℃）（200~500℃）。

75em; text-indent: 2em; font-family: ; font-size: 16px; box-sizing: border-box; -webkit-tap-highlight-color: rgba(0, 0, 0, 0);">“”，。，，。，，，，0.
013 W/（m·K）；TiO2、TiO2，2。“”，，，。

75em; text-indent: 2em; font-family: ; font-size: 16px; box-sizing: border-box; -webkit-tap-highlight-color: rgba(0, 0, 0, 0);">，。2080，，。，，、。，，，，。，。，，。，300~400 ℃，，，。

75em; text-indent: 2em; font-family: ; font-size: 16px; box-sizing: border-box; -webkit-tap-highlight-color: rgba(0, 0, 0, 0);">、、，。，，。（），，，，（、）。，。

、、，。，，。（），，，，（、）。，。

75em; text-indent: 2em; font-family: ; font-size: 16px; box-sizing: border-box; -webkit-tap-highlight-color: rgba(0, 0, 0, 0);">，。，。，，“”（200℃）（200~500℃）。

，。，。，，“”（200℃）（200~500℃）。

75em; text-indent: 2em; font-family: ; font-size: 16px; box-sizing: border-box; -webkit-tap-highlight-color: rgba(0, 0, 0, 0);">“”，。，，。，，，，0.
013 W/（m·K）；TiO2、TiO2，2。“”，，，。

“”，。，，。，，，，0.
013 W/（m·K）；TiO2、TiO2，2。“”，，，。

75em; text-indent: 2em; font-family: ; font-size: 16px; box-sizing: border-box; -webkit-tap-highlight-color: rgba(0, 0, 0, 0);">，。2080，，。，，、。，，，，。，。，，。，300~400 ℃，，，。

，。2080，，。，，、。，，，，。，。，，。，300~400 ℃，，，。

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2 2

75em; text-indent: 2em; font-family: ; font-size: 16px; box-sizing: border-box; -webkit-tap-highlight-color: rgba(0, 0, 0, 0);">，2，。，，。，。，、、，。，，。、、，，。，，。

75em; text-indent: 2em; font-family: ; font-size: 16px; box-sizing: border-box; -webkit-tap-highlight-color: rgba(0, 0, 0, 0);">，，。，。，。2，“”（200℃）。

75em; text-indent: 2em; font-family: ; font-size: 16px; box-sizing: border-box; -webkit-tap-highlight-color: rgba(0, 0, 0, 0);">，，“”，TI-200。，。，0.
136W/（m·K）；，180℃，4mmTI-200，80℃，。200℃，、、、（4）。

75em; text-indent: 2em; font-family: ; font-size: 16px; box-sizing: border-box; -webkit-tap-highlight-color: rgba(0, 0, 0, 0);">，2，。，，。，。，、、，。，，。、、，，。，，。

，2，。，，。，。，、、，。，，。、、，，。，，。

75em; text-indent: 2em; font-family: ; font-size: 16px; box-sizing: border-box; -webkit-tap-highlight-color: rgba(0, 0, 0, 0);">，，。，。，。2，“”（200℃）。

，，。，。，。2，“”（200℃）。

75em; text-indent: 2em; font-family: ; font-size: 16px; box-sizing: border-box; -webkit-tap-highlight-color: rgba(0, 0, 0, 0);">，，“”，TI-200。，。，0.
136W/（m·K）；，180℃，4mmTI-200，80℃，。200℃，、、、（4）。

，，“”，TI-200。，。，0.
136W/（m·K）；，180℃，4mmTI-200，80℃，。200℃，、、、（4）。

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75em; text-indent: 2em; font-family: ; font-size: 16px; box-sizing: border-box; -webkit-tap-highlight-color: rgba(0, 0, 0, 0);">，VOCs51.
5g/L，，、、，SH/T3022—2011《》（1）。

75em; text-indent: 2em; font-family: ; font-size: 16px; box-sizing: border-box; -webkit-tap-highlight-color: rgba(0, 0, 0, 0);">，VOCs51.
5g/L，，、、，SH/T3022—2011《》（1）。

，VOCs51.
5g/L，，、、，SH/T3022—2011《》（1）。

75em; text-indent: 2em; font-family: ; font-size: 16px; box-sizing: border-box; -webkit-tap-highlight-color: rgba(0, 0, 0, 0);">1 TI-200

75em; text-indent: 2em; font-family: ; font-size: 16px; box-sizing: border-box; -webkit-tap-highlight-color: rgba(0, 0, 0, 0);">1 TI-200

1 TI-200

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75em; text-indent: 2em; font-family: ; font-size: 16px; box-sizing: border-box; -webkit-tap-highlight-color: rgba(0, 0, 0, 0);">、，，，、。200~400℃，、。，。，Si—O—Si，，（5）。

75em; text-indent: 2em; font-family: ; font-size: 16px; box-sizing: border-box; -webkit-tap-highlight-color: rgba(0, 0, 0, 0);">、，，，、。200~400℃，、。，。，Si—O—Si，，（5）。

、，，，、。200~400℃，、。，。，Si—O—Si，，（5）。

75em; text-indent: 0em; font-family: ; font-size: 16px; box-sizing: border-box; -webkit-tap-highlight-color: rgba(0, 0, 0, 0);">

75em; text-indent: 0em; font-family: ; font-size: 16px; box-sizing: border-box; -webkit-tap-highlight-color: rgba(0, 0, 0, 0);">

75em; text-indent: 2em; font-family: ; font-size: 16px; box-sizing: border-box; -webkit-tap-highlight-color: rgba(0, 0, 0, 0);">，“”，400 ℃（6）。

75em; text-indent: 2em; font-family: ; font-size: 16px; box-sizing: border-box; -webkit-tap-highlight-color: rgba(0, 0, 0, 0);">，“”，400 ℃（6）。

，“”，400 ℃（6）。

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75em; text-indent: 2em; font-family: ; font-size: 16px; box-sizing: border-box; -webkit-tap-highlight-color: rgba(0, 0, 0, 0);">500℃，0.
138W/（m·K）。HG/T3362—2003（2），。

75em; text-indent: 2em; font-family: ; font-size: 16px; box-sizing: border-box; -webkit-tap-highlight-color: rgba(0, 0, 0, 0);">500℃，0.
138W/（m·K）。HG/T3362—2003（2），。

500℃，0.
138W/（m·K）。HG/T3362—2003（2），。

75em; text-indent: 2em; font-family: ; font-size: 16px; box-sizing: border-box; -webkit-tap-highlight-color: rgba(0, 0, 0, 0);">2 TI-500

75em; text-indent: 2em; font-family: ; font-size: 16px; box-sizing: border-box; -webkit-tap-highlight-color: rgba(0, 0, 0, 0);">2 TI-500

2 TI-500

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3 3

75em; text-indent: 2em; font-family: ; font-size: 16px; box-sizing: border-box; -webkit-tap-highlight-color: rgba(0, 0, 0, 0);">，、、、，。

75em; text-indent: 2em; font-family: ; font-size: 16px; box-sizing: border-box; -webkit-tap-highlight-color: rgba(0, 0, 0, 0);">(1) ，，。，，、。，2，。

75em; text-indent: 2em; font-family: ; font-size: 16px; box-sizing: border-box; -webkit-tap-highlight-color: rgba(0, 0, 0, 0);">(2) ，，、。，，。。

75em; text-indent: 2em; font-family: ; font-size: 16px; box-sizing: border-box; -webkit-tap-highlight-color: rgba(0, 0, 0, 0);">(3) ，。，，、、。

75em; text-indent: 2em; font-family: ; font-size: 16px; box-sizing: border-box; -webkit-tap-highlight-color: rgba(0, 0, 0, 0);">(4) ，，。，，。

75em; text-indent: 2em; font-family: ; font-size: 16px; box-sizing: border-box; -webkit-tap-highlight-color: rgba(0, 0, 0, 0);">，、、、，。

，、、、，。

75em; text-indent: 2em; font-family: ; font-size: 16px; box-sizing: border-box; -webkit-tap-highlight-color: rgba(0, 0, 0, 0);">(1) ，，。，，、。，2，。

(1) ，，。，，、。，2，。

75em; text-indent: 2em; font-family: ; font-size: 16px; box-sizing: border-box; -webkit-tap-highlight-color: rgba(0, 0, 0, 0);">(2) ，，、。，，。。

(2) ，，、。，，。。

75em; text-indent: 2em; font-family: ; font-size: 16px; box-sizing: border-box; -webkit-tap-highlight-color: rgba(0, 0, 0, 0);">(3) ，。，，、、。

(3) ，。，，、、。

75em; text-indent: 2em; font-family: ; font-size: 16px; box-sizing: border-box; -webkit-tap-highlight-color: rgba(0, 0, 0, 0);">(4) ，，。，，。

(4) ，，。，，。