Anti-scale fuel gas heating furnace for oil field

Abstract

The utility model discloses an anti-scale fuel gas heating furnace for an oil field. The anti-scale fuel gas heating furnace comprises a heating furnace and an anti-scale system, the anti-scale system comprises a circulating water pump, a dosing tank, a liquid taking pipe, a liquid return pipe, a sleeve, a spiral flow guide rib plate and a sleeve liquid outlet; a spiral flow guide rib plate is arranged on the outer surface of the furnace tube, a sleeve is tightly attached to the outer edge of the spiral flow guide rib plate, a sleeve liquid inlet is formed in the position, close to the smoke box, of the front end of the upper-layer sleeve, a sleeve liquid outlet is formed in the side, close to the combustor, of the lower-layer sleeve, a liquid taking tube inlet is formed in the inner side of a sleeve elbow, and a liquid taking tube outlet is communicated with a circulating water pump inlet. An outlet of the circulating water pump is communicated with an inlet of the liquid return pipe; an outlet of the liquid return pipe is communicated with the sleeve liquid inlet; an outlet of the dosing tank is communicated with a circulating water pump inlet pipe through a pipeline; by additionally arranging the sleeve and the spiral flow guide rib plate, boiler water is in a high-speed rotational flow state on the surface of the boiler tube, the flow speed of the boiler water on the surface of the boiler tube is remarkably increased, and a good scale inhibition and prevention effect can be achieved.

Description

Technical Field

[0001] This utility model relates to the field of heating furnace technology, specifically to an anti-scaling gas-fired heating furnace for oil fields. Background Technology

[0002] In crude oil extraction, the crude oil gathering and transportation process requires heating the crude oil and oily wastewater to the required temperature to facilitate subsequent transportation, sedimentation, separation, dehydration, water mixing, hot washing, and initial processing of the crude oil. The heating process mainly uses heating furnaces, which primarily use natural gas as fuel. The combustion of the fuel releases a large amount of heat energy and produces high-temperature flue gas. The high-temperature flue gas heats the liquid medium and is then discharged through a chimney. This type of oilfield heating furnace is widely used in various oilfield production plants.

[0003] Because the heated medium—boiler water—has a complex composition and contains a certain proportion of crude oil, and due to the influence of the traditional furnace structure, the flow velocity of the boiler water outside the fire tubes is relatively low. Large particles of contaminants in the boiler water easily deposit and adhere to the tube walls. Furthermore, under prolonged high-temperature conditions, this quickly forms hard scale. This scale not only increases the furnace's heat transfer resistance, reduces its thermal efficiency, and increases production fuel costs, but also, when the scale is large, can cause localized excessively high tube wall temperatures, potentially leading to furnace burn-through and leakage. Although scale inhibitors are regularly added to the incoming main pipe in actual production… However, due to the large amount of water inside the furnace, once the chemicals added in the pipelines enter the furnace water, their concentration is immediately diluted, and the furnace water reaching the furnace tube surface essentially loses its scale-inhibiting effect. Furthermore, this scale cannot be treated online and can only be removed through periodic dredging. Often, only loose surface scale can be removed, while hard internal scale remains untreated. This not only involves high maintenance costs and the impact of furnace shutdowns on oil production, but also fails to address the future operation of the furnace under high thermal resistance and low efficiency conditions. This long-term high-energy-consuming state undoubtedly generates more operating costs and causes serious environmental pollution. Therefore, it is necessary to propose a scale-inhibiting gas-fired furnace for oilfields to solve the above problems. Utility Model Content

[0004] The purpose of this invention is to address the shortcomings of existing technologies by providing an anti-scaling gas-fired heater for oil fields, thereby solving the problem of hard scale easily forming on the walls of the heater tubes.

[0005] This utility model provides a scale-resistant gas-fired heater for oil fields, including a heater and a scale-resistant system; the heater includes a heater shell, a furnace tube unit, a smoke box, and a burner; the furnace tube unit is located inside the heater shell, the smoke box is located at the upper front part of the heater shell, and the burner is located at the lower middle part of the front part of the heater shell; the furnace tube unit is U-shaped and includes upper and lower furnace tubes connected at one end; the burner head is inserted into the lower furnace tube and the upper furnace tube is inserted into the smoke box;

[0006] The anti-scaling system includes a circulating water pump, a dosing tank, a liquid intake pipe, a liquid return pipe, a sleeve, spiral guide ribs, and a sleeve outlet. Spiral guide ribs are provided on the outer surface of the furnace tube, and a sleeve is located close to the outer edge of the spiral guide ribs. The sleeve inlet is located at the front end of the upper sleeve near the smoke box, and the sleeve outlet is located on the lower sleeve near the burner. The liquid intake pipe inlet is located inside the sleeve bend, and the liquid intake pipe outlet is connected to the circulating water pump inlet. The circulating water pump outlet is connected to the liquid return pipe inlet, and the liquid return pipe outlet is connected to the sleeve inlet. The dosing tank outlet is connected to the circulating water pump inlet pipe via a pipeline.

[0007] Furthermore, a maintenance platform is fixedly installed on the top of the heating furnace shell, and the side of the maintenance platform is fixedly connected to the ladder. The heating furnace shell has a liquid inlet and a liquid outlet at the rear. The smoke box has a smoke exhaust port and an explosion-proof door. The heating furnace shell has a fixed support at the bottom. A smoke temperature meter is installed on the smoke box.

[0008] Furthermore, the upper wall of the heating furnace shell is provided with a maintenance manhole and a safety valve interface, the lower wall of the heating furnace shell is provided with a drain outlet, and the side wall of the heating furnace shell is provided with an oil collection outlet; the interior of the heating furnace shell is also provided with a first partition, a second partition and a third partition.

[0009] Furthermore, the dosing tank is fixed to the ground by its support legs, and an automatic shut-off valve and a check valve are installed on the outlet pipe of the dosing tank.

[0010] Furthermore, the anti-scaling system is equipped with two circulating water pumps, which are variable frequency pumps. Pressure gauges are installed on the inlet and outlet pipes of the circulating water pumps, flow meters are installed on the outlet pipes of the circulating water pumps, and automatic shut-off valves are installed on the inlet and outlet pipes of the circulating water pumps.

[0011] Furthermore, a flange connection is used between the casing and the furnace tube.

[0012] This utility model has the following beneficial effects: The oilfield-grade anti-scaling gas-fired heater provided by this utility model, through the installation of a sleeve and spiral guide ribs, allows the boiler water to be in a high-speed swirling state on the surface of the furnace tubes, significantly increasing the boiler water flow velocity and achieving excellent scale inhibition and prevention effects. The higher convective heat transfer coefficient between the boiler water and the furnace tubes effectively improves the operating thermal efficiency of the heater and the comprehensive utilization rate of the gas. The sleeve structure on the outside of the furnace tubes allows the scale inhibitor to better exert its scale inhibition effect, avoiding the problem of the agent dissolving in the large volume of water inside the furnace, causing its concentration to decrease and leading to scale inhibition failure. The high-efficiency heat exchange rate can quickly respond to changes in oil production process parameters, making the heater more controllable. The online scale inhibition method avoids the problem of periodic shutdown and sludge removal required by conventional heaters, reducing operating and maintenance costs and preventing the impact of shutdown on oil production. Real-time online monitoring of the furnace tube surface's operating status through external circulation system parameters provides a favorable guarantee for the safe, stable, and efficient operation of the heater. Attached Figure Description

[0013] To more clearly illustrate the technical solutions in the embodiments of this utility model or the prior art, the drawings used in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this utility model. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0014] Figure 1 This is a front view of the scale-resistant gas-fired heater for oil fields according to this utility model;

[0015] Figure 2 yes Figure 1 A-direction view;

[0016] Figure 3 yes Figure 1 The view from direction b;

[0017] Figure 4 yes Figure 1 The view from direction c;

[0018] Figure 5 yes Figure 3 AA section view;

[0019] Figure 6 yes Figure 1 BB section view;

[0020] Figure 7 This is a three-dimensional structural diagram of the scale-resistant gas-fired heater for oil fields according to this utility model. Figure 1 ;

[0021] Figure 8This is a three-dimensional structural diagram of the scale-resistant gas-fired heater for oil fields according to this utility model. Figure 2 ;

[0022] Figure 9 This is a front view of the furnace tube unit;

[0023] Figure 10 This is a side view of the furnace tube unit;

[0024] Figure 11 This is a top view of the furnace tube unit;

[0025] Figure 12 This is a 3D diagram of the furnace tube unit.

[0026] Illustrations: 1-Maintenance platform; 2-Maintenance manhole; 3-Dosing tank; 4-Safety valve interface; 5-Fume exhaust port; 6-Explosion-proof door; 7-Smoke box; 8-Burner; 9-Heating furnace shell; 10-Circulating water pump; 11-Ladder; 12-Dosing tank support leg; 13-Drain outlet; 14-Heating furnace support; 15-Oil inlet; 16-Return pipe; 17-Taking pipe; 18-Heating furnace outlet; 19-Heating furnace inlet; 20-Furnace tube unit; 21-Shell; 22-Third baffle; 23-First baffle; 24-Second baffle; 25-Shell outlet; 201-Furnace tube; 202-Spiral guide rib. Detailed Implementation

[0027] It should be noted that, unless otherwise specified, the embodiments and features described in this application can be combined with each other. The present invention will now be described in detail with reference to the accompanying drawings and embodiments. It should be pointed out that the following detailed description is illustrative and intended to provide further explanation of the present application. Unless otherwise specified, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application pertains.

[0028] Please see Figures 1 to 12 This utility model embodiment mainly comprises a conventional system and an anti-scaling system. The conventional system is based on the structure of an existing heating furnace, mainly consisting of a heating furnace shell 9, a heating furnace support 14, a furnace tube 201, a smoke box 7, an explosion-proof door 6, a burner 8, a maintenance platform 1, a ladder 11, a maintenance manhole 2, a safety valve interface 4, a drain outlet 13, a smoke exhaust outlet 5, a heating furnace liquid inlet 19, a heating furnace liquid outlet 18, a first partition 23, a second partition 24, a third partition 22, and an oil collection port 15. The anti-scaling system mainly consists of a circulating water pump 10, a chemical dosing tank 3, chemical dosing tank support legs 12, a liquid intake pipe 17, a liquid return pipe 16, a sleeve 21, a spiral guide rib 202, and a sleeve outlet 25.

[0029] A maintenance platform 1 is fixedly installed on the top of the heating furnace shell 9. The side of the maintenance platform 1 is fixedly connected to the ladder 11. A heating furnace liquid inlet 19 and a heating furnace liquid outlet 18 are provided at the rear of the heating furnace shell 9. A smoke box 7 is provided at the upper front of the heating furnace shell 9. A smoke outlet 5 and an explosion-proof door 6 are provided on the smoke box 7. A burner 8 is installed at the lower middle front of the heating furnace shell 9. A heating furnace support 14 is fixedly installed at the bottom of the heating furnace shell 9, and the heating furnace support 14 supports the ground.

[0030] The upper wall of the heating furnace shell 9 is provided with a maintenance manhole 2 and a safety valve interface 4. The lower wall of the heating furnace shell 9 is provided with a drain outlet 13. The side wall of the heating furnace shell 9 is provided with an oil collection outlet 15. The interior of the heating furnace shell 9 is provided with a furnace tube 201, a first partition 23, a second partition 24 and a third partition 22. The burner 8 head is inserted into the lower furnace tube 201 and the upper furnace tube 201 is inserted into the smoke box 7.

[0031] The outer surface of the furnace tube 201 is provided with a spiral guide rib 202. A sleeve 21 is provided close to the outer edge of the spiral guide rib 202. The liquid inlet of the sleeve 21 is located at the front end of the upper sleeve 21 near the smoke box 7. The liquid outlet 25 of the sleeve is located on the side of the lower sleeve 21 near the burner 8. The inlet of the liquid taking pipe 17 is located inside the elbow of the sleeve 21. The outlet of the liquid taking pipe 17 is connected to the inlet of the circulating water pump 10. The outlet of the circulating water pump 10 is connected to the inlet of the return pipe 16. The outlet of the return pipe 16 is connected to the liquid inlet of the sleeve 21. The dosing tank 3 is fixed to the ground by the dosing tank support leg 12. The outlet of the dosing tank 3 is connected to the inlet pipe of the circulating water pump 10 through a pipeline.

[0032] Preferably, the reinforcing ribs between the sleeve 21 and the furnace tube 201 adopt a spiral structure, which can effectively enhance the strength of the furnace tube 201 and the sleeve 21, and also guide the flow of the boiler water flowing in the sleeve 21, so that the boiler water flows in a high-speed spiral state. On the one hand, it can reduce the probability of impurities in the boiler water depositing on the surface of the furnace tube 201, and on the other hand, it can improve the heat transfer intensity between the boiler water and the furnace tube 201, which is beneficial to the heat transfer effect between the heat source and the boiler water.

[0033] Preferably, the anti-scaling system is equipped with two circulating water pumps 10, operating in a one-on-one standby mode to ensure reliable operation of the anti-scaling system; the circulating water pumps 10 are variable frequency pumps to optimize adaptation to different operating conditions of the heating furnace; pressure gauges are installed on the inlet and outlet pipes of the circulating water pumps 10, and flow meters are installed on the outlet pipe of the circulating water pumps 10 to monitor the operating resistance parameters of the anti-scaling system in real time to determine the operating status of the furnace tube 201 surface; automatic shut-off valves are installed on the inlet and outlet pipes of the circulating water pumps 10 to facilitate fault diagnosis and maintenance of the circulating water pumps.

[0034] Preferably, the outlet pipe of the dosing tank 3 is equipped with an automatic shut-off valve and a check valve to control the frequency and amount of dosing, so as to ensure the anti-scaling effect of the furnace tube 201 and prevent the backflow of furnace water, which would disrupt the normal operation of the system.

[0035] Preferably, a flue gas temperature gauge is provided on the smoke box 7 to monitor the exhaust gas temperature in real time, so as to guide the optimized operation of the heating furnace in real time.

[0036] Preferably, the sleeve 21 and the furnace tube 201 are connected by a flange, which facilitates the maintenance of the furnace tube 201 and the spiral guide rib plate 202 during equipment overhaul.

[0037] This invention uses a sleeve 21 to enclose the furnace tube 201 and the spiral guide rib 202 internally, forming a sealed channel between the outer wall of the furnace tube 201, the spiral guide rib 202, and the inner wall of the sleeve 21, serving as the flow space for the boiler water. Boiler water from the circulating water pump 10 enters the flow space within the sleeve 21 through the return pipe 16 and the inlet of the sleeve 21, and flows at high speed along the spiral channel. The boiler water exchanges heat with the hot flue gas through the wall of the furnace tube 201. After releasing heat and cooling down, the water is discharged to the chimney through the smoke box 7 and the exhaust port 5. After absorbing heat and heating up, the boiler water flows out through the liquid outlet 25 of the casing into the water space of the heating section, where it directly mixes and transfers heat with the water stored in the heating section and the low-temperature liquid from the liquid inlet 19 of the heating furnace. At the same time, the boiler water in the furnace enters the inlet of the circulating water pump 10 through the liquid take-up pipe 17. Driven by the circulating water pump 10, the boiler water enters the water space inside the casing 21 again through the liquid return pipe 16 and the liquid inlet of the casing 21 to start the next cycle of heat exchange.

[0038] After the boiler water in the heating section absorbs heat and rises in temperature, it overflows from the water space of the heating section through the first baffle 23 and enters the oil collection section of the heating furnace through the second baffle 24. The oil and water in the boiler water are initially separated under the action of gravity. The water, which has a higher density, enters the buffer section of the heating furnace through the third baffle 22 and enters the next process through the liquid outlet 18 of the heating furnace. The crude oil, which has a lower density, floats in the upper space of the oil collection section and is discharged and collected through the oil collection port 15.

[0039] Therefore, by adopting the structure of sleeve 21 and spiral guide rib 202, the flow velocity of boiler water on the surface of the boiler tube wall can be significantly increased, and the amount of dirt deposited in the boiler water on the boiler tube wall can be significantly reduced, thereby reducing boiler tube scaling and lowering the overall heat transfer resistance. Due to the increase in boiler water flow velocity, the heat transfer intensity between the boiler tube wall and the boiler water is effectively improved, increasing the heat transfer efficiency of the heating furnace. In order to fundamentally avoid the boiler tube scaling problem, a dosing point is set at the liquid intake pipe 17 near the inlet of the circulating water pump 10. The scale inhibitor is stored in the dosing tank 3, and the dosing operation is performed according to the pump inlet and outlet pressure difference set value or a fixed cycle for the same circulating liquid volume, optimizing the control of the dosing frequency of the scale inhibitor. The dosage and amount of additives are adjusted to achieve the best reagent concentration and scale inhibition effect, ensuring the safe operation of the heating furnace. At the same time, by observing the correspondence between the circulating liquid volume and the pressure difference between the pump inlet and outlet, in addition to determining whether scale has occurred in the furnace tube 201, it can also intuitively reflect whether there are problems such as bulging or burn-through leakage in the furnace tube 201, thereby further improving the safety early warning level of the heating furnace. In addition, in order to optimize the operating status of the heating furnace, the operating frequency of the circulating water pump 10 can be controlled by the data of the flue gas temperature meter on the flue gas box 7, so that the exhaust gas temperature is within an optimal range. This ensures that the heating furnace has high thermal efficiency and avoids the risk of corrosion of the flue gas box 7 and the chimney caused by excessively low exhaust gas temperature.

[0040] As can be seen from the above embodiments, the oilfield-grade anti-scaling gas-fired heater of this utility model adopts a unique sleeve structure and a self-circulating boiler water system in the heating section, which significantly increases the boiler water flow velocity on the outer wall of the furnace tube, effectively slowing down the deposition and adhesion rate of contaminants in the boiler water on the surface of the furnace tube, and forming a good self-cleaning and scale-inhibiting effect on the outer wall of the furnace tube. Unique spiral guide ribs are set on the outer wall of the furnace tube, which on the one hand strengthens the strength of the furnace tube and the sleeve, and on the other hand creates conditions for the swirling flow of the boiler water. The high-speed rotating boiler water outside the furnace tube significantly reduces the heat transfer resistance on the surface of the furnace tube, enhances the heat exchange intensity of the furnace tube, and improves the heat exchange efficiency between the boiler water and the high-temperature flue gas inside the furnace tube. An online dosing system is provided, which, combined with the characteristics of the furnace tube and sleeve structure, effectively controls the concentration of scale inhibitor in the boiler water in contact with the furnace tube, significantly improving the scale prevention effect. Using the pressure and pressure difference of the circulating water pump inlet and outlet as the basis for judging the operating status of the furnace tube, it is possible to diagnose in a timely and effective manner whether there is scaling or leakage in the furnace tube, providing a reliable guarantee for the inherent safety of the heater. The forced convection heat exchange method effectively improves the heat exchange rate between high-temperature flue gas and boiler water, accelerates the change process of boiler outlet water temperature with the amount of gas, significantly reduces the delay caused by the large capacity of water in the furnace to the system response speed, and improves the ease of control of the boiler.

[0041] It should be noted that the terminology used herein is for the purpose of describing particular embodiments only and is not intended to limit the exemplary embodiments according to this application. As used herein, the singular form is intended to include the plural form as well, unless the context clearly indicates otherwise. Furthermore, it should be understood that when the terms "comprising" and / or "including" are used in this specification, they indicate the presence of features, steps, operations, devices, components, and / or combinations thereof.

[0042] It should be noted that the terms "first," "second," etc., in the specification, claims, and accompanying drawings of this application are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence. It should be understood that such data can be interchanged where appropriate so that the embodiments of this application described herein can be implemented, for example, in sequences other than those illustrated or described herein.

[0043] The above description is merely a preferred embodiment of this utility model and is not intended to limit the utility model. Various modifications and variations can be made to this utility model by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this utility model should be included within the protection scope of this utility model.

Claims

1. A scale-resistant gas-fired heater for oilfield use, characterized in that, include: A heating furnace and an anti-scaling system; the heating furnace includes a heating furnace shell (9), a furnace tube unit (20), a smoke box (7), and a burner (8); the furnace tube unit (20) is located inside the heating furnace shell (9), the smoke box (7) is located at the upper front of the heating furnace shell (9), and the burner (8) is located at the lower middle front of the heating furnace shell (9); the furnace tube unit (20) is U-shaped and includes two layers of furnace tubes (201) connected at one end; the head of the burner (8) is inserted into the lower layer of furnace tube (201), and the upper layer of furnace tube (201) is inserted into the smoke box (7); The anti-scaling system includes a circulating water pump (10), a dosing tank (3), a liquid intake pipe (17), a liquid return pipe (16), a sleeve (21), a spiral guide rib (202), and a sleeve outlet (25); the outer surface of the furnace tube (201) is provided with a spiral guide rib (202), and a sleeve (21) is provided close to the outer edge of the spiral guide rib (202). The liquid inlet of the sleeve (21) is located at the front end of the upper sleeve (21) near the smoke box (7). The outlet of the casing (25) is located on the side of the lower casing (21) near the burner (8). The inlet of the liquid taking pipe (17) is located inside the elbow of the casing (21). The outlet of the liquid taking pipe (17) is connected to the inlet of the circulating water pump (10). The outlet of the circulating water pump (10) is connected to the inlet of the return pipe (16). The outlet of the return pipe (16) is connected to the inlet of the casing (21). The outlet of the dosing tank (3) is connected to the inlet pipe of the circulating water pump (10) through a pipeline.

2. The oilfield anti-scaling gas-fired heater as described in claim 1, characterized in that, A maintenance platform (1) is fixedly installed on the top of the heating furnace shell (9). The side of the maintenance platform (1) is fixedly connected to the ladder (11). The heating furnace shell (9) is provided with a heating furnace liquid inlet (19) and a heating furnace liquid outlet (18) at the rear. The smoke box (7) is provided with a smoke exhaust port (5) and an explosion-proof door (6). The heating furnace shell (9) is fixedly installed with a heating furnace support (14) at the bottom. The smoke box (7) is provided with a smoke temperature meter.

3. The oilfield anti-scaling gas-fired heater as described in claim 1, characterized in that, The upper wall of the heating furnace shell (9) is provided with a maintenance manhole (2) and a safety valve interface (4), the lower wall of the heating furnace shell (9) is provided with a drain port (13), and the side wall of the heating furnace shell (9) is provided with an oil collection port (15); the interior of the heating furnace shell (9) is also provided with a first partition (23), a second partition (24) and a third partition (22).

4. The oilfield anti-scaling gas-fired heater as described in claim 1, characterized in that, The dosing tank (3) is fixed to the ground by the dosing tank support leg (12), and the outlet pipe of the dosing tank (3) is equipped with an automatic shut-off valve and a check valve.

5. The oilfield anti-scaling gas-fired heater as described in claim 1, characterized in that, The anti-scaling system is equipped with two circulating water pumps (10). The circulating water pumps (10) are variable frequency pumps. Pressure gauges are installed on the inlet and outlet pipes of the circulating water pumps (10). Flow meters are installed on the outlet pipes of the circulating water pumps (10). Automatic shut-off valves are installed on the inlet and outlet pipes of the circulating water pumps (10).

6. The oilfield anti-scaling gas-fired heater as described in claim 1, characterized in that, The sleeve (21) and the furnace tube (201) are connected by a flange.

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