Hot air blowing device for preventing condensation and blockage of chemical pipeline

Abstract

The utility model discloses a hot air blowing device for preventing condensation and blockage of a chemical pipeline, which belongs to the technical field of hot air blowing of the chemical pipeline and comprises a hot air generator and an air source premixer, the hot air generator is used for heating an air source and outputting the heated air source through a nozzle; the air source premixer is of a tubular structure based on the Bernoulli principle and comprises a contraction pipe section, a throat pipe section and an expansion pipe section, the air source premixer is provided with a main fluid inlet, a secondary fluid inlet and a mixed outlet which are communicated with the contraction pipe section, the throat pipe section and the expansion pipe section respectively, the main fluid inlet is used as an air inlet for guiding in an air source, and the secondary fluid inlet is used as an air outlet for guiding in the air source. The secondary fluid inlet is connected with a protective gas conveying pipeline, and the mixing outlet is communicated with an air inlet of the hot air generator; the device is simple in structure and good in mixing uniformity, in addition, the use safety is achieved by diluting the oxygen content in the air, and meanwhile the introduction amount of the protective gas can be flexibly adjusted according to the use environment.

Description

Technical Field

[0001] The utility model belongs to the technical field of hot air blowing for chemical pipelines, and in particular relates to a hot air blowing device for preventing condensation and blockage of chemical pipelines. Background Technology

[0002] In the operation scenario of chemical plants, affected by cold air, the media in the pipelines of chemical plants are prone to ice or condensation, which needs to be solved by local blowing of external hot air to ensure the fluidity of the media in the pipelines.

[0003] The hot air gun is the most widely used air heating equipment. Due to the limitation of its working mode, the traditional hot air gun can only be directly applied in ordinary air environment. This conventional application method has many disadvantages, especially in the special environment of chemical equipment, it cannot meet the strict safety requirements.

[0004] Chemical plants often involve various flammable, explosive, oxidizable substances and process processes that have special requirements for the environment and atmosphere. Oxygen and other components contained in the ordinary air environment may react violently with certain substances in the chemical plant, thereby causing safety accidents such as fire, explosion, and runaway chemical reactions, which seriously threaten the stable operation of the chemical plant and the life safety of the operators.

[0005] In response to the above problems, the utility model patent with authorization announcement number CN201237352Y discloses a hot air gun, which avoids high-temperature oxidation by connecting nitrogen or a non-oxidizing gas source to the air inlet of the hot air gun. However, the disadvantage is that the non-oxidizing gas source is directly heated in the hot air gun, which may cause combustion or explosion during the heating process due to trace combustibles or impurities contained in the gas source. In addition, the non-oxidizing gas source is the only heated gas source, resulting in a large demand, which may easily lead to high cost of using the non-oxidizing gas source and high concentration of the non-oxidizing gas source in the local space. For example, when the non-oxidizing gas source is nitrogen, the high nitrogen content in the local space may easily lead to a decrease in the oxygen content, thereby affecting the health of the staff.

[0006] Based on the above analysis, this application designs a hot air blowing device for preventing condensation and blockage in chemical pipelines. Contents of utility model

[0007] The purpose of the utility model is to provide a hot air purge device for preventing condensation and blockage in chemical pipelines. The gas source premixer in the device is based on the principle of Bernoulli fluid dynamics. Air is used as the main heating gas source and protective gas is used as the auxiliary gas source to dilute the oxygen content in the heating gas source, thereby reducing the probability of dangerous events such as fire, explosion, and chemical reaction out of control. At the same time, it can also reduce the cost of using protective gas and its impact on the surrounding environment.

[0008] In order to solve the above problems, this solution provides a hot air blowing device for preventing condensation and blockage of chemical pipelines, including:

[0009] A hot air generator, which is used to heat the air source and output the heated air source through a nozzle;

[0010] The gas source premixer is a tubular structure based on the Bernoulli principle, which includes a contraction pipe section, a throat pipe section and an expansion pipe section, and the gas source premixer is provided with a main fluid inlet, a secondary fluid inlet and a mixing outlet respectively connected to the contraction pipe section, the throat pipe section and the expansion pipe section. The main fluid inlet is used as an air inlet to introduce an air source, the secondary fluid inlet is connected to a protective gas delivery pipeline to introduce protective gas, and the mixing outlet is connected to the air inlet of the hot air generator to introduce the mixed gas into the hot air generator.

[0011] As a preferred solution of the present application: the contraction tube section, throat tube section and expansion tube section constitute a mixing chamber, the mixing chamber comprises multiple stages connected in series, and the secondary fluid inlet is connected to the throat tube section at the primary end.

[0012] As a preferred solution of the present application: the secondary fluid inlet comprises a plurality of secondary fluid inlets, and the plurality of secondary fluid inlets are equidistantly arranged in a ring around the outer periphery of the throat section.

[0013] As a preferred solution of the present application: the inlet direction of the secondary fluid inlet forms an angle θ with the flow direction of the primary fluid to ensure that the secondary fluid forms a counter-impact flow relative to the primary fluid.

[0014] As a preferred solution of the present application: the gas source premixer comprises a main material layer and a thermal insulation coating, wherein the main material layer is made of any one of stainless steel or ceramic coated metal, and the thermal insulation coating is made of any one of aerogel or ceramic fiber.

[0015] As a preferred solution of the present application: the nozzle is integrally formed with the hot air generator, or the nozzle is an independent high temperature resistant mechanism, which is connected to the air outlet of the hot air generator through a connector.

[0016] As a preferred solution of the present application: the protective gas includes any one of nitrogen and carbon dioxide.

[0017] As a preferred solution of this application: the hot air generator is a hot air gun or a hot air blower.

[0018] Compared with the prior art, the advantages of this application are:

[0019] The hot air purging device of this scheme includes an air source premixer, a hot air generator, a protective gas delivery pipeline and a nozzle, wherein the hot air generator is used to heat the air source and output it to the purging position, the air source premixer is arranged at the inlet end of the hot air generator, and adopts a tubular structure based on the Bernoulli principle. The air source premixer uses air as the main heating air source and the protective gas as the auxiliary air source to dilute the oxygen content in the heating air source, and can use the negative pressure formed by the hot air generator and the Bernoulli principle to inhale air and protective gas to mix and form a mixed gas without additional auxiliary pump parts. The mixed gas is introduced into the hot air generator through the mixing outlet The hot air generator heats the introduced mixed gas and then outputs it through the nozzle to achieve heating and preheating of the outer wall of the chemical pipeline; it can be seen that the gas source premixer in this scheme realizes the premixing of the two gases based on the Bernoulli principle, which not only has a simple structure, but also has good mixing uniformity and reduces the cost of use. In addition, this scheme uses protective gas as an auxiliary gas source to dilute the oxygen content in the air, which can ensure the safety of use on the basis of reducing the amount of protective gas used. At the same time, the amount of protective gas introduced can be flexibly adjusted according to the use environment, which improves the flexibility of use and reduces the amount of protective gas used, and has certain practical value and economic benefits. Brief Description of the Figures

[0020] Figure 1 This is the working principle diagram of the hot air blowing device for preventing condensation and blockage of chemical pipelines provided by the utility model;

[0021] Figure 2 This is a schematic diagram of the exploded structure of the hot air blowing device for preventing condensation and blockage in chemical pipelines provided by the utility model;

[0022] Figure 3 This is a schematic diagram of the cross-sectional structure of the gas source premixer provided by the utility model.

[0023] Reference Symbols

[0024] 10 is a hot air generator; 101 is an air inlet; 102 is an air outlet; 20 is a gas source premixer; 201 is a main fluid inlet; 202 is a secondary fluid inlet; 203 is a mixed outlet; 204 is a contraction pipe section; 205 is a throat section; 206 is an expansion pipe section; 208 is a main material layer; 209 is a heat insulation coating; 30 is a protective gas delivery pipeline; 40 is a nozzle. Specific implementation method

[0025] The following is a further detailed description of the utility model in conjunction with specific implementation methods and with reference to the accompanying drawings. It should be emphasized that the following description is merely exemplary and is not intended to limit the scope of the utility model and its application.

[0026] This embodiment provides a hot air blowing device for preventing condensation and blockage of chemical pipelines, which at least includes a hot air generator 10, a gas source premixer 20 and a protective gas delivery pipeline 30, such as Figure 1-2 As shown in the figure, it is a structural principle diagram and a structural exploded diagram of the device provided in this embodiment. The hot air generator 10 is used to heat the air source, and output the heated air source through the nozzle 40 to the corresponding chemical pipeline to implement hot air purging heating or preheating. Specifically, the heated air source can be used to purge and heat the outer wall of the chemical pipeline to solve the problem of medium condensation in the pipeline, and can also be introduced into the chemical pipeline to be used for purging and preheating. The specific selection can be made according to actual needs. In addition, the hot air generator 10 can not only heat the air, but also actively output the heated air source, that is, it can drive Air flows, so it can be understood that the hot air generator 10 should include a fan assembly. In this embodiment, the hot air generator 10 is preferably a hot air gun or a hot air blower; the air source premixer 20 is connected to the air inlet 101 end of the hot air generator 10, and the air source premixer 20 is a tubular structure based on the Bernoulli principle, which includes a contraction pipe section 204, a throat section 205 and an expansion pipe section 206, wherein the expansion pipe section 206 is longer than the contraction pipe section 204, and the contraction pipe section 204, the throat section 205 and the expansion pipe section 206 form a mixing chamber, and the air source premixer 20 is also provided with a contraction pipe section and a The main fluid inlet 201, the secondary fluid inlet 202 and the mixing outlet 203 connected to the expansion pipe section 204, the throat section 205 and the expansion pipe section 206, the design of the main fluid inlet 201, the secondary fluid inlet 202 and the mixing outlet 203 forms a three-way structure of the gas source premixer 20. It can be understood that according to the Bernoulli principle, in the three-way structure, the caliber of the secondary fluid inlet 202, the caliber of the mixing outlet 203 and the caliber of the main fluid inlet 201 should increase in sequence, and the caliber of the secondary fluid inlet 202 should be smaller than the caliber of the main fluid inlet 201 and the mixing outlet 203 (specifically, the caliber of the main fluid inlet 201 can be greater than the caliber of the main fluid inlet 201). The main fluid inlet 201 and the mixed outlet 203 are located at opposite ends of the air source premixer 20 in the axial direction. The main fluid inlet 201 is used as an air inlet to introduce the air source in the current environment. The secondary fluid inlet 202 is connected to the protective gas delivery pipeline 30 to introduce the protective gas. It can be understood that the protective gas delivery pipeline 30 should be provided with a protective gas flow control mechanism to ensure the reasonable and effective use of the protective gas. The mixed outlet 203 is connected to the air inlet 101 of the hot air generator 10 to introduce the mixed gas into the hot air generator 10.

[0027] In this embodiment, the protective gas is mainly a gas that is resistant to high temperatures and has low oxidizing properties, which improves the stability of the gas source during heating and use. In this embodiment, the protective gas preferably includes nitrogen (N 2 ) and carbon dioxide (CO 2) because the industrial site of this unit has sufficient nitrogen (N 2 ) source, so nitrogen (N 2 ).

[0028] Specifically, the hot air blowing device of this scheme includes an air source premixer 20, a hot air generator 10, a protective gas delivery pipeline 30 and a nozzle 40, wherein the air source premixer 20 adopts a tubular structure based on the Bernoulli principle, and the air source premixer 20 uses air as the main heating gas source and the protective gas as the auxiliary gas source to dilute the oxygen content in the heating gas source, and can use the negative pressure formed by the hot air generator 10 and the Bernoulli principle to inhale air and protective gas into the premixing chamber for mixing and then forming a mixed gas without additional auxiliary pump parts for pressurization, and the mixed gas is introduced into the hot air generator 10 through the mixing outlet 203, and the hot air generator 10 heats the introduced mixed gas and then passes through The nozzle 40 outputs to achieve heating or preheating of the chemical pipeline; it can be seen that the gas source premixer 20 in this scheme realizes the premixing of the two gases based on the Bernoulli principle, which not only has a simple structure, but also has good mixing uniformity and reduces the cost of use. In addition, this scheme uses protective gas as an auxiliary gas source to dilute the oxygen content in the air, which can ensure the safety of use on the basis of reducing the amount of protective gas used, thereby reducing the probability of dangerous events such as fire, explosion, and chemical reaction out of control. The amount of protective gas introduced can also be flexibly adjusted according to the use environment, thereby improving the flexibility of use and reducing the cost of using protective gas and its impact on the surrounding environment. It has certain practical value and economic benefits.

[0029] If Figure 3 is a schematic diagram of the internal structure of the gas source premixer 20 provided in this embodiment. As can be seen from the figure, the contraction pipe section 204, the throat section 205 and the expansion pipe section 206 include multiple stages connected in series, and the secondary fluid inlet 202 is connected to the throat section 205 located at the primary end.

[0030] Specifically, in order to improve the premixing efficiency and ensure that the protective gas can be quickly and evenly mixed with the air, this embodiment designs a multi-stage mixing chamber consisting of a contraction pipe section 204, a throat section 205 and an expansion pipe section 206. This embodiment preferably designs two stages, and the mixing chambers of each stage are connected in series in sequence. Among them, the volume of the first-stage mixing chamber is smaller than that of the second-stage mixing chamber. According to Figure 3It can be seen that the contraction angle of the contraction tube section 204 in the primary mixing chamber is greater than the contraction angle of the contraction tube section 204 in the secondary mixing chamber, and the length of the diffusion tube section in the primary mixing chamber is less than the length of the diffusion tube section in the secondary mixing chamber. The purpose of adopting this design structure is to ensure that the two airflows flow at high speed in the primary mixing chamber to achieve sufficient mixing, improve (reduce) the airflow velocity through the secondary mixing chamber, and mix again. Reducing the airflow velocity in the secondary mixing chamber is conducive to the effective use of hot airflow, especially when used for purging and heating the outer wall of chemical pipelines, which can avoid the rapid diffusion of hot airflow caused by high-speed airflow and reduce the lack of effective utilization.

[0031] When in use, air enters as the main airflow through the main fluid inlet 201 and then passes through the primary mixing chamber and the secondary mixing chamber in sequence. According to the Bernoulli principle, a low-pressure area is formed at the junction of the contraction section and the throat section 205 (this embodiment will have two low-pressure areas, and the low-pressure area is the key area for airflow mixing). At this time, under the action of negative pressure, not only the flow rate of the air increases, but also the secondary fluid, that is, the protective gas, is promoted to be quickly injected through the secondary fluid inlet 202. At this time, the first mixing of the two airflows in the low-pressure area is achieved. Since the air pressure in the low-pressure area in the primary mixing chamber is lower than that in the secondary mixing chamber, the two airflows flow and mix rapidly in the low-pressure area of ​​the primary mixing chamber and then enter the diffusion section. In the diffusion section, the pressure is restored, and the high-speed mixed airflow is decelerated, further promoting mixing, and then enters the low-pressure area and the diffusion section of the secondary mixing chamber for re-mixing. The specific mixing mode is the same as that of the primary mixing chamber, and this embodiment will not be repeated; through two mixing, not only the uniform mixing of air and protective gas is achieved without the need to add other auxiliary guide plates, but also the flow rate of the mixed hot airflow can be adjusted to a suitable state.

[0032] In this embodiment, the secondary fluid inlet 202 includes multiple secondary fluid inlets 202, which are equidistantly arranged on the outer periphery of the throat section 205, that is, the gas source premixer 20 is provided with multiple secondary fluid inlets 202, and the multiple secondary fluid inlets 202 are respectively connected to the corresponding branch pipes in the protective gas delivery pipeline 30, and the multiple branch pipes can be started simultaneously or individually. The use of this structure can achieve uniformity and controllability of the introduction of protective gas at the source, ensuring that the protective gas and air can be quickly and evenly mixed.

[0033] In this embodiment, the inlet direction of the secondary fluid inlet 202 forms an angle θ with the flow direction of the primary fluid, and the angle θ is preferably 35-45° to ensure that the secondary fluid forms a counter-impact flow relative to the primary fluid, and then utilizes shear force to assist mixing, further improving the uniformity of mixing.

[0034] In this embodiment, the gas source premixer 20 is a high temperature resistant device, which includes a main material layer 208 and a heat insulation coating 209, wherein the main material layer 208 is made of stainless steel or ceramic coated metal, and the heat insulation coating 209 is made of aerogel or ceramic fiber; the gas source premixer 20 of this structure can be unaffected by the high temperature of the hot air generator 10 and ensure the safety of the staff.

[0035] In this embodiment, the nozzle 40 is integrally formed with the hot air generator 10, or the nozzle 40 is an independent high temperature resistant structure, which is connected to the air outlet 102 of the hot air generator 10 through a connector. In this embodiment, the nozzle 40 is preferably an independent high temperature resistant structure, which can be fixed to the air outlet 102 end of the hot air generator 10 through an interference fit or a connector such as a clamp. It can be understood that the specific structure of the nozzle 40 can be selected from a flat duckbill type or a porous type according to the actual application environment.

[0036] The above is only an embodiment of the utility model, and the common knowledge such as the known specific structure and characteristics in the scheme is not described in detail here. It should be pointed out that for those skilled in the art, several improvements can be made without departing from the utility model, and these should also be regarded as the protection scope of the utility model, which will not affect the effect of the implementation of the utility model and the practicality of the patent. The scope of protection required by this application shall be based on the content of the claims, and the specific implementation methods and other records in the specification can be used to interpret the content of the claims.

Claims

1. A hot air blowing device for preventing condensation and blockage of chemical pipelines, characterized in that: include: A hot air generator, which is used to heat the air source and output the heated air source through a nozzle; An air source premixer is a tubular structure based on the Bernoulli principle, comprising a contraction section, a throat section and an expansion section, and the air source premixer is provided with a main fluid inlet, a secondary fluid inlet and a mixing outlet respectively connected to the contraction section, the throat section and the expansion section, the main fluid inlet is used as an air inlet to introduce an air source, the secondary fluid inlet is connected to a protective gas delivery pipeline to introduce protective gas, and the mixing outlet is connected to the air inlet of the hot air generator to introduce the mixed gas into the hot air generator.

2. The hot air blowing device for preventing condensation and blockage of chemical pipelines according to claim 1 is characterized in that: The contraction tube section, the throat tube section and the expansion tube section constitute a mixing chamber, which comprises multiple stages connected in series, and the secondary fluid inlet is connected to the throat tube section at the primary end.

3. The hot air blowing device for preventing condensation and blockage of chemical pipelines according to claim 1 is characterized in that: The secondary fluid inlet comprises a plurality of secondary fluid inlets, and the plurality of secondary fluid inlets are equidistantly arranged in a ring around the outer circumference of the throat section.

4. The hot air blowing device for preventing condensation and blockage of chemical pipelines according to claim 1 is characterized in that: The inlet direction of the secondary fluid inlet forms an angle θ with the flow direction of the primary fluid, so as to ensure that the secondary fluid forms a counter-impact flow relative to the primary fluid.

5. The hot air blowing device for preventing condensation and blockage of chemical pipelines according to claim 1 is characterized in that: The gas source premixer comprises a main material layer and a thermal insulation coating, wherein the main material layer is made of any one of stainless steel or ceramic-coated metal, and the thermal insulation coating is made of any one of aerogel or ceramic fiber.

6. The hot air blowing device for preventing condensation and blockage of chemical pipelines according to claim 1 is characterized in that: The nozzle is integrally formed with the hot air generator, or the nozzle is an independent high temperature resistant mechanism, which is connected to the air outlet of the hot air generator through a connecting piece.

7. The hot air blowing device for preventing condensation and blockage of chemical pipelines according to claim 1 is characterized in that: The protective gas includes any one of nitrogen and carbon dioxide.

8. The hot air blowing device for preventing condensation and blockage of chemical pipelines according to claim 1 is characterized in that: The hot air generator is a hot air gun or a hot air blower.

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