Low-thermal burner device

WO2025074355A3PCT designated stage expired Publication Date: 2025-07-03PTT EXPLORATION & PROD PUBLIC CO LTD +1
View PDF 5 Cites 0 Cited by

Patent Information

Application Number
PCT/IB2024/060155
Authority / Receiving Office
WO · WO
Patent Type
Applications
Current Assignee / Owner
Priority Date
2023-10-03
Filing Date
2024-10-16
Publication Date
2025-07-03

AI Technical Summary

Technical Problem

Conventional flare systems struggle to efficiently combust exhaust gases with extremely low flammability, leading to safety concerns and potential health risks due to incomplete gas disposal.

Method used

The low-thermal burner device incorporates a hooded exhaust stack with a perforated pipe and supplementary gas release pipes equipped with baffle plates, enhancing the mixing time and efficiency of exhaust and supplementary gases to improve combustion.

Benefits of technology

This design effectively increases the combustion efficiency and flammability of low-BTU exhaust gases, ensuring complete and rapid combustion, thus maintaining system balance and ensuring safety.

✦ Generated by Eureka AI based on patent content.

Smart Images

  • Figure IB2024060155_03072025_PF_FP_ABST
    Figure IB2024060155_03072025_PF_FP_ABST
Patent Text Reader

Abstract

A low-thermal burner device according to the present invention comprises an exhaust stack of a general flare system that receives exhaust gas through an exhaust pipe, allowing the exhaust gas to flow out from one end of the exhaust stack to come into contact with the flame from the igniter and ignite. Supplementary gas is then introduced through a supplementary gas pipe to mix with the exhaust gas. Said exhaust stack is further assembled to a geometrically shaped hood for extending the mixing time between the two gases and preventing wind or external factors from disrupting the internal mixing and combustion process. A baffle plate is also provided such that it is assembled to the supplementary gas release pipe, which serves as a component that obstructs the flow of the exhaust gas, causing the exhaust gas to disperse internally or before colliding with a supplementary gas flow path, thereby enhancing the efficiency of gas mixing.
Need to check novelty before this filing date? Find Prior Art

Description

[0001] LOW-THERMAL BURNER DEVICE

[0002] TECHNICAL FIELD

[0003] Petroleum engineering and petroleum exploration and production process, particularly a low-thermal burner device

[0004] BACKGROUND OF THE INVENTION

[0005] In large industrial plants, particularly in industries that generate or produce large amounts of gas, a "flare" is considered an essential component of the safety system according to international standards. It must be present to ensure the safety of living beings and property within the area surrounding the plants. The flare serves to burn exhaust gas, which is surplus gas that is not cost-effective for further use or gas with uncertain components produced within the plant, whether arising from emergency situations, malfunctions, machinery maintenance, or normal operations. It prevents the dispersion of hazardous gases, such as flammable gases that are heavier than air, and helps avoid the accumulation of gases or pressure within the system. Initially, flares are typically in the form of an exhaust stack, which may be at or above ground level, depending on the design. The exhaust gas, after most of its liquid components have been extracted, is released through the exhaust stack, where an igniter is used to create a flame at the stack outlet, causing the released gas to ignite at the outlet and produce a flame above the stack to prevent damage that could occur in case the flame directly contacts the exhaust stack.

[0006] The designer must ensure that at least one of the igniters remains lit at all times in order to bum all the exhaust gas entering the system and prevent the leakage of exhaust gas. Additionally, it is necessary to establish a system or component to prevent exhaust gas or external air from backflowing from the outlet of the exhaust stack into the system. Such backflow may cause the air and exhaust gas to mix inside, creating a flammable mixture that could draw the flame igniting at the exhaust stack outlet into the exhaust piping system and lead to an explosion.

[0007] It can be seen that the flare is an extremely important invention. Therefore, it is necessary to carefully integrate various technologies to ensure that the flare can address the issues accurately and safely.

[0008] One of the issues with flares that arise and may significantly impact safety is that when the exhaust gas to be disposed of is a low-BTU gas, relying solely on an igniter may not be sufficient to effectively bum the released gas. Moreover, it may cause the igniter flame to extinguish and disrupt the overall system balance. Initially, temperature sensing devices are used to monitor the status of the ignited flame to ensure that system operators can immediately detect when the flame goes out and promptly re-ignite it. Additionally, a system for delivering different types of supplementary gas has been developed, such as flammable gases or gases that react with exhaust gas to form a flammable mixture, thereby increasing the ignition capacity of the exhaust gas. Moreover, steam injection is used to mix with the exhaust gas that needs to be burned, with the aim of significantly improving the combustion efficiency of the gas.

[0009] The aforementioned methods can effectively enhance the combustion efficiency of exhaust gas with low flammability, as well as significantly reduce the likelihood of the flame at the exhaust stack outlet being extinguished. However, in a case where the exhaust gas is extremely low-BTU gas or low-heat value gas, such as gas containing a high proportion of carbon dioxide, even when supplementary gas is introduced to mix with the exhaust gas, standard flare system design regulations generally require controlling the velocity of the exhaust gas passing through the exhaust stack at a high rate. This is intended to prevent backflow of gases at the exhaust stack outlet into the stack. As a result, the time available for mixing the exhaust gas, supplementary gas, and water mist to enhance combustion efficiency is insufficient. The combustion efficiency or flammability of the exhaust gas therefore cannot be increased to an optimal level.

[0010] In other words, conventional methods for enhancing combustion efficiency cannot address the issue of disposing of exhaust gas with extremely low flammability and may lead to long-term health impacts for operators. Additionally, they fail to resolve safety concerns in surrounding areas due to the inability to effectively dispose of exhaust gas. Therefore, an invention that provides a solution for developing a flare system capable of efficiently disposing of exhaust gas with extremely low flammability is essential for industries.

[0011] The low-thermal burner device according to the present invention comprises a conventional flare with an exhaust stack equipped with a hood at its end. The hood is intended to prevent external wind or disturbances and to extend the distance to increase the mixing time for the exhaust gas and supplementary gas. The exhaust stack comprises a supplementary gas release pipe which releases supplementary gas for mixing with the exhaust gas flowing through the exhaust pipe. The exhaust gas is released such that it collides with a supplementary gas flow path. Said exhaust pipe is configured as a perforated pipe, allowing the exhaust gas inside to flow out and mix with the supplementary gas. The perforations are arranged in a zigzag pattern or aligned in parallel straight lines with alternating placements to provide space for the dispersion of exhaust gas for optimal mixing with the supplementary gas.

[0012] At least one supplementary gas pipe is a conventional pipe which allows the supplementary gas to flow in a manner that collides with the exhaust gas. Each supplementary gas pipe comprises at least one baffle plate, which is a metal plate positioned along the direction of the exhaust gas flow, with one end bent to obstruct the exhaust gas flow. This is to allow the exhaust gas to collide with the baffle plate and disperse prior to collision with the supplementary gas in a case where the flow rate, velocity, or pressure of the two gases are similar or after the exhaust gas flows into the supplementary gas flow path with a higher flow rate, velocity, or pressure. Consequently, the supplementary gas is able to mix more effectively with the exhaust gas.

[0013] This design significantly enhances the efficiency of mixing the exhaust gas and supplementary gas and improves the combustion efficiency or flammability of the extremely low-flammability exhaust gas to a level where it can burn effectively, thus preventing hazards arising from the accumulation or dispersion of exhaust gas.

[0014] SUMMARY OF THE INVENTION

[0015] A low-thermal burner device according to the present invention comprises an exhaust stack assembled to a hood at an end where the exhaust gas is released to ignite the flame of an igniter. An exhaust pipe is used and configured as a perforated pipe, with the perforations arranged in a zigzag pattern, to allow the exhaust gas to collide with a supplementary gas. A baffle plate is assembled to a supplementary gas release pipe to obstruct the exhaust gas flow path and cause the exhaust gas to either disperse before colliding with the supplementary gas or within the supplementary gas flow path, resulting in improved mixing.

[0016] The invention aims to improve the properties of exhaust gas with extremely low flammability to enable it to be completely and rapidly combusted at a rate corresponding to the exhaust gas release velocity. This allows the flare system to maintain the system balance and continue to operate safely for both the system itself and the surrounding environment.

[0017] BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Fig. 1 shows an aspect of the components of the low-thermal burner device.

[0019] Fig. 2 shows an upper cross-sectional view of the low-thermal burner device. DETAILED DESCRIPTION

[0020] The details of the invention will now be described to provide a better understanding, in conjunction with the accompanying drawings. The same reference numbers in the drawings are used to denote identical or similar components throughout the description of the invention.

[0021] Any aspects illustrated herein shall encompass applications to other aspects of the present invention, unless otherwise specified.

[0022] Technical or engineering terms used herein are defined as understood by a person of ordinary skill in the art, unless otherwise specified.

[0023] The terms “consist of,” “comprise,” “contain,” “have / has,” and “include” are open-ended verbs. For example, “consisting of,” “comprising,” “containing,” “having,” and “including” one or more components are not intended to be limited to the one or more components mentioned but also encompass components that are not specified.

[0024] The low-thermal burner device as presented herein is merely an illustration of one construction and embodiment of the low-thermal burner device.

[0025] The low-thermal burner device is an invention which enhances the performance of a conventional flare to enable it to combust gases with extremely low flammability. This is achieved by extending the mixing time for supplementary gas and exhaust gas and creating the dispersion of exhaust gas for better mixing with the supplementary gas.

[0026] Fig. 1 shows an aspect of the components of the low-thermal burner device and Fig. 2 shows an upper cross-sectional view of the low-thermal burner device.

[0027] The low-thermal burner device comprises a flare that operates in the same manner as a conventional flare. In the example shown, only certain components of the flare are illustrated, including an exhaust stack 100, which contains an exhaust pipe 110 for conveying exhaust gas from a factory’s gas system or surrounding areas. Said exhaust gas first undergoes an extraction process to remove any liquids contained therein. The exhaust pipe 110 is configured as a branched pipe extending outward from a center of the exhaust stack 100 and is perforated from the outside to form through-holes to direct the exhaust gas to collide with the supplementary gas. The perforations are arranged in a zigzag pattern or aligned in parallel straight lines with alternating placements to provide space for the exhaust gas to flow through and mix with the supplementary gas more effectively. The exhaust pipe 110 may be configured as a perforated ring-shaped pipe positioned parallel to a circumference of the exhaust stack 100 to allow the exhaust gas to effectively disperse throughout the exhaust stack 100.

[0028] Another component provided inside the exhaust stack 100 is a supplementary gas release pipe 130 which allows the mixing of the released supplementary gases with the exhaust gas leaving the exhaust pipe 110 to enhance the combustion efficiency of the exhaust gas. According to this example, the supplementary gas release pipe 130 is arranged as a group of pipes that alternate between an arrangement of the exhaust pipe 110. In this example, the supplementary gas release pipe 130 receives external supplementary gas through the supplementary gas pipe 131 and releases it in an upward direction, parallel to the exhaust stack 100. The supplementary gas release pipe 130 is arranged between each of the branched exhaust pipes 110 to direct the flow of the exhaust gas released from each exhaust pipe 110 to collide with the supplementary gas flow path and mixing thoroughly with the supplementary gas.

[0029] In addition, an end portion of the supplementary gas release pipe 130 further comprises the baffle plate 150, which is a high-heat-resistant metal plate positioned such that it obstructs the exhaust gas flow to maximize the dispersion of the exhaust gas to enhance the mixing efficiency of the two exhaust gases.

[0030] According to this example, the baffle plate 150 further comprises arms which are connected between the supplementary gas release pipe 130 and the baffle plate 150, allowing the baffle plate 150 to be positioned within the flow path of the supplementary gas and the exhaust gas. This is intended to enable the dispersion of the exhaust gas within the supplementary gas flow path. According to the initial design, the exhaust gas released from the exhaust pipe 110 has pressure and velocity suitable to allow it to penetrate the supplementary gas flow path and then collide with the baffle plate 150. This causes the exhaust gas to disperse within the supplementary gas flow path and provides the most efficient mixing or reaction.

[0031] Normally, if the exhaust gas disperses in a position far from the supplementary gas flow path, the exhaust gas in a dispersed state will lose its velocity. It may then be carried upward by the supplementary gas, which flows at a higher velocity to prevent backflow, without having fully mixed or reacted with the supplementary gas.

[0032] In a case where the exhaust gas needs to have much higher pressure or velocity than the supplementary gas, which would cause the exhaust gas to break through the supplementary gas flow path or greatly disperse upon colliding with the baffle plate 150 and exit the supplementary gas flow path, the arms may be shortened and the baffle plate 150 may be positioned to obstruct the exhaust gas before it enters the supplementary gas flow path. This may involve changing the orientation of the baffle plate from its usual position of blocking the exhaust gas flow to an angle relative to the exhaust gas flow, which forces the exhaust gas to disperse before it collides with the supplementary gas and scatters droplets into the supplementary gas flow path. In a case where the exhaust gas has much higher velocity than the supplementary gas, this dispersion before collision will help reduce the velocity of the exhaust gas to allow it to remain within the supplementary gas flow path and provide optimal mixing or reaction. Additionally, the position of the baffle plate 150 may be adjusted to be located behind the supplementary gas flow path using the same concept.

[0033] That is to say, the length of the arms, as well as the size or angle of installation of the baffle plate 150, can be freely adjusted depending on the velocity, pressure, type of exhaust gas and supplementary gas, and surrounding environment such as wind speed, air pressure, or humidity. This allows the mixing or reaction between the two gases to occur as efficiently as possible.

[0034] The exhaust stack 100 comprises an igniter 120 which is provided in a position where the exhaust gas must pass through and is pre-ignited. This allows the exhaust gas, after being mixed with the supplementary gas, to come into contact with the flame and ignite. Additionally, the exhaust stack 100 further comprises a spray nozzle 121 for injecting water or liquids with properties that enhance the combustion efficiency, which are mixed with the exhaust gas within the exhaust stack 100.

[0035] An open end of the exhaust stack 100 is also assembled to a hood 140 to prevent external air or disturbances from affecting the mixing of exhaust gas and supplementary gas, while also helping to extend the flow distance of the exhaust gas and supplementary gas to increase the duration of their mixing.

[0036] In other words, in a case where some of the exhaust gas has not been suitably mixed or reacted, the combustion efficiency will not be high enough to achieve complete combustion or ignition. The hood 140 will prevent the exhaust gas from dispersing by increasing the flow distance, allowing more time for the exhaust gas to mix with supplementary gas, air, or water. In a case where the size of the exhaust stack 140 is sufficient to create an appropriate duration, the exhaust gas, which is generally unable to mix with supplementary gas, water, or air in time due to the speed or flow rate control, can mix effectively with the aiding elements before leaving the hood 140.

[0037] The hood 140 has a hollow geometric shape, preferably a hollow cylinder, with a diameter equal to or close to that of the exhaust stack 100 as much as possible so that the gas flow rate within the hood 140 is the same as or similar to the gas flow rate within the exhaust stack 100. The hood 140 may be designed with a diameter larger or smaller than the exhaust stack 100, depending on the specific properties of the supplementary gas and exhaust gas, as well as the surrounding environment such as humidity, temperature, or wind speed. If the hood 140 has a larger diameter than the exhaust stack 100, it will result in a lower gas flow rate within the hood 140 due to the increased cross-sectional area. Conversely, if the hood 140 has a smaller diameter than the exhaust stack 100, the gas flow rate within the hood 140 will increase accordingly.

[0038] In another embodiment, the hood 140 may take other geometric shapes, such as a truncated cone, which causes the gas flow rate within the hood 140 to vary depending on the height or position of the gas cluster at that moment. If the hood 140 is shaped as an upright cone, it can accelerate the gas flow to promote the mixing of gases. Conversely, if the hood 140 is shaped as an inverted cone, it can help slow down the gas flow. The hood 140 may need to be assembled to a load-bearing beam at appropriate positions to mitigate the gravitational force acting on such geometric structure.

[0039] The assembling of the hood 140 to the exhaust stack 100 can be configured such that the hood 140 is mounted on top of the exhaust stack 100, with its end slightly covering the exhaust stack 100 while leaving an opening at the bottom. Alternatively, the hood 140 may be elevated from the exhaust stack 100, creating a side gap that allows external air to flow into the hood 140 from below by the suction force generated by the gas flow and the temperature inside the hood 140. This enhances the combustion efficiency of the gases within the exhaust stack 100 without requiring the installation of additional devices.

[0040] In another embodiment, the hood 140 is configured to be fully closed to prevent air from entering from any direction other than the top, which is open to the outside. This configuration completely prevents gas leakage, which is suitable in a case where the mixed gases have sufficient combustibility and do not require external air. Therefore, it is possible to effectively prevent the dissipation of heat through other openings, which could otherwise cause damage to various components. The exhaust gas, which has been mixed with various aiding elements until it becomes flammable, will be ignited by the flame from the igniter 120, along with some gas that has already been ignited. This allows combustion to occur to completely eliminate the mixed exhaust gas before any gas can leave of the hood 140. Any modifications or changes to this invention may be clearly understood and implemented by those skilled in the art within the scope and spirit of the present invention, as outlined in the appended claims.

[0041] BEST MODE OF THE INVENTION

[0042] Best mode of the invention is as described in the detailed description of the invention.

Claims

WHAT IS CLAIMED IS:

1. A low-thermal burner device comprises an exhaust stack (100) containing an exhaust pipe (110) for conveying exhaust gas and releasing it in the exhaust stack (100); a supplementary gas release pipe (130) for receiving supplementary gas from an external source through a supplementary gas pipe (131) to release the supplementary gas for mixing with the exhaust gas; and an igniter (120) installed at a position through which the exhaust gas flows, characterized in that an end portion of the supplementary gas release pipe (130) further comprises a baffle plate (150), which is a high-heat-resistant metal plate installed to obstruct the exhaust gas flow and disperse the exhaust gas before mixing with the supplementary gas.

2. The low-thermal burner device according to claim 1, wherein the exhaust pipe (110) is configured as a branched pipe extending outward from a center of the exhaust stack (100) and is perforated from an outside to form through-holes to direct the exhaust gas to collide with the supplementary gas, the perforations being arranged in a zigzag pattern or aligned in parallel straight lines with alternating placements.

3. The low-thermal burner device according to claim 1, wherein the exhaust pipe (110) is configured as a perforated ring-shaped pipe positioned parallel to the circumference of the exhaust stack (100).

4. The low-thermal burner device according to claim 2, wherein the supplementary gas release pipe (130) is arranged between each of the branched exhaust pipes (HO).

5. The low-thermal burner device according to claim 1, wherein the baffle plate (150) further comprises arms which are connected between the supplementary gas release pipe (130) and the baffle plate (150), allowing the baffle plate (150) to be positioned within a supplementary gas flow path.

6. The low-thermal burner device according to claim 1 or 6, wherein the baffle plate (150) is positioned to obstruct the exhaust gas within the supplementary gas flow path or at a point before entering the supplementary gas flow path at least in one aspect.

7. The low-thermal burner device according to claim 1, wherein the exhaust stack (100) further comprises a spray nozzle (121) for injecting water or liquids with properties that enhance the combustion efficiency of the exhaust gas within the exhaust stack (100).

8. The low-thermal burner device according to claim 1, wherein the exhaust stack(100) is further assembled to a hood (140) at an open end of the exhaust stack (100), said hood (140) being in a hollow geometric shape.

9. The low-thermal burner device according to claim 8, wherein the hood (140) is in a hollow cylindrical shape.

10. The low-thermal burner device according to claim 8, wherein the hood (140) is assembled to the exhaust stack (100) such that an end portion of the hood (140) slides down to cover the exhaust stack (100) while leaving an opening at the bottom, with the hood (140) either elevated from the exhaust stack (100) to create a side gap, or fully closed to prevent air from entering from any direction other than the top, which is open to the outside, to prevent gas leakage in at least one aspect.

Citation Information

Patent Citations

  • Flare stack combustion apparatus and method

    US20040248055A1

  • Smokeless liquid dual-phase burner system

    US20070231758A1

  • Tandem flare

    US20200340671A1

  • Radially-injected steam for smokeless flaring

    US4098566A

  • Apparatus and method to add kinetic energy to a low pressure waste gas flare burner

    US4652232A