Gas phase thermal unit

Abstract

A gas phase thermal unit, which includes an elongated vertically extending tubular housing having an interior cavity, a lower portion and an upper portion. A plurality of radial burner head conduits are positioned within the interior cavity in a lower portion of the housing, each of the conduits having a plurality of orifices, the orifices being oriented to create a vortex of gas movement. An ignition system is used to ignite gas emitted from the orifices to form high intensity flames. There is also a primary source of forced air having a radial air supply conduit associated with each burner head conduit, where each radial air supply conduit is adapted to create a vortex of air movement while delivering combustion air to a root of the flames of one of the burner head conduits, and a secondary source of forced air having associated air supply outlets adapted to create a vortex of air movement while delivering air to a tip of the flames to minimize oxide formation.

Description

FIELD OF THE INVENTION

The present invention relates to a thermal unit, which consumes gas phase fuel.

BACKGROUND OF THE INVENTION

In the oil and gas industry, there are applications in which gas vented from a gas well must be disposed of properly before releasing to the atmosphere. A number of thermal units have been developed for this purpose and are variously described in the prior art as “gas flares” or “gas incinerators”. However, as the oil and gas drilling industry becomes more environmentally responsible in regards to air pollution, a system with higher combustion efficiency is required to meet current and future stringent air quality guidelines.

SUMMARY OF THE INVENTION

According to the present invention there is provided a gas phase thermal unit, which includes an elongated vertically extending tubular housing having an interior cavity, a lower portion and an upper portion. A plurality of radial burner head conduits are positioned within the interior cavity in a lower portion of the housing, each of the conduits having a plurality of orifices, the orifices being oriented to create a vortex of gas movement. An Ignition System is used to ignite gas emitted from the orifices to form high intensity flames. There is also a primary source of forced air having a radial air supply conduit associated with each burner head conduit, where each radial air supply conduit is adapted to create a vortex of air movement while delivering combustion air to the root of the flames of one of the burner head conduits, and a secondary source of forced air having associated air supply outlets adapted to create a vortex of air movement while delivering air to a tip of the flames to minimize oxide formation. With the high vortex movement created around the burner inside the vertically elongated extending tubular housing, clean combustion with high efficiency and flame suppression can both be achieved by re-circulating heat and active chemical species to the base of the flame.

BRIEF DESCRIPTION OF THE DRAWINGS

These and other features of the invention will become more apparent from the following description in which reference is made to the appended drawings, the drawings are for the purpose of illustration only and are not intended to in any way limit the scope of the invention to the particular embodiment or embodiments shown, wherein:

FIG. 1 is a side elevation view, in section, of a gas phase thermal unit constructed in accordance with the teachings of the present invention.

FIG. 2 is a top plan view, in section, of the gas phase thermal unit illustrated in FIG. 1, showing burner head conduit and primary air supply conduit detail.

FIG. 3 is a detailed top plan view of one of the burner head conduits and primary air supply conduits illustrated in FIG. 2.

FIG. 4 is a detailed transverse sectional view of the burner head conduit and primary air supply conduit illustrated in FIG. 3.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT

The preferred embodiment, a gas phase thermal unit generally identified by reference numeral 10, will now be described with reference to FIG. 1 through 4.

Structure and Relationship of Parts:

Referring now to FIG. 1, there is shown gas phase thermal unit 10, including an elongated vertically extending tubular housing 12 having an interior cavity 14, a lower portion 16, an upper portion 18, a top 15 and a bottom 17. Housing 12 may be insulated with thermal insulation 20, such as ceramic fibre insulation. Upper portion 18 of housing 12 is of a length adapted to conceal any visible flame. Low pressure gas from portable tanks regularly associated with drilling and well testing procedures are vented through a low pressure vent line 22, which extends from the exterior of thermal unit 10 to lower portion 16 of housing 12. Referring to FIG. 2, a plurality of radial burner head conduits 24 are positioned within interior cavity 14 in lower portion 16 of housing 12. Referring to FIG. 3, each conduit 24 has a plurality of orifices 26 that are oriented to create a vortex of gas movement. Referring again to FIG. 1, an Ignition System 28, with a continuous pilot system, is used to ignite gas emitted from orifices 26 to form high intensity flames. There is a primary source of forced air 30, and a secondary source of forced air 36. Referring to FIG. 2, primary source 30 has a radial air supply conduit 32 associated with each burner head conduit 24. Each radial air supply conduit 32 is adapted to create a vortex of air movement while delivering combustion air to the root of the flames of one of the burner head conduits 24. Secondary source of forced air 36 has associated air supply outlets 38 that are adapted to create a vortex of air movement while delivering air to the tip of the flames to minimize oxide formation. Referring to FIG. 1 a gas inlet 40 extends from below up to a manifold 42 depicted in FIG. 4 and is used to supply gas to radial burner head conduits 24. It is likely that liquids will be carried in the gas to be burned. Therefore, referring again to FIG. 1, a liquid separation chamber 44 is included that underlies manifold 42. Liquid separation chamber 44 is adapted to contain liquids carried in the gas such that liquids are separated by means of centripetal force into the base of the liquid separation chamber 44.

Referring to FIG. 1, sub-floor 19, insulated or non-insulated, acts as a heat shield against high heat radiation from the burner to the controls/instruments and operators. Without this protective heat shield, direct radiant heat energy from the burner can potentially cause damage to the equipment and injuries to the operators.

Referring to FIG. 1, to stabilize gas phase thermal unit 10 in the upright, operational position, bottom 17 of housing 12 is mounted on a skid 46 and laydown skid 48. Skid 46 is of a sufficient weight to support housing 46 in a free standing vertical orientation. For example, skid 46 may be filled with concrete. In addition, a laydown skid 48 that extends along housing 12 is provided for transportation purposes.

With a burner design that creates high vortex movement, this system can achieve combustion efficiency as high as 99.9999% depending on the well gas composition and flow rate. Also, with the properly staged air burner configuration and a vertically elongated extending tubular housing, the flame can be fully concealed reducing ground level heat radiation and emitting light source which can cause discomfort to local residents.

Operation:

The use and operation of gas phase thermal unit 10 will now be described with reference to FIGS. 1 through 4. First, tubular housing 12 having an interior cavity 14, a lower portion 16, an upper portion 18, a top 15 and a bottom 17 is erected on skid 46. Low pressure gas from portable tanks regularly associated with drilling and well testing procedures are vented through a low pressure vent line 22, which extends from the exterior of thermal unit 10 to lower portion 16 of housing 12. Gas to be flared passes through gas inlet 40, through the liquid separation chamber 44, to manifold 42, and then to a plurality of radial burner head conduits 24 that are positioned within interior cavity 14 in lower portion 16 of housing 12. Referring to FIG. 2, each conduit 24 has a plurality of orifices 26 that are oriented to create a vortex of gas movement. The gas is ignited using an Ignition System 28, with a continuous pilot system. The gas is mixed with air at the bottom of the flame to improve combustion using air from primary source of forced air 30 through radial air supply conduit 32, and at the top of the flame to minimize oxidation formation using air from secondary source of forced air 36 through supply outlets 38. Referring to FIG. 2, primary source 30 has a radial air supply conduit 32 associated with each burner head conduit 24. Referring to FIG. 1, liquids that are carried in the gas to be burned are separated by means of centripetal force into the base of the liquid separation chamber 44 that underlies manifold 42.

In this patent document, the word “comprising” is used in its non-limiting sense to mean that items following the word are included, but items not specifically mentioned are not excluded. A reference to an element by the indefinite article “a” does not exclude the possibility that more than one of the element is present, unless the context clearly requires that there be one and only one of the elements.

It will be apparent to one skilled in the art that modifications may be made to the illustrated embodiment without departing from the spirit and scope of the invention as hereinafter defined in the Claims.

Claims

1. A gas phase thermal unit, comprising:

an elongated vertically extending tubular housing having an interior cavity, a lower portion and an upper portion;

a plurality of radial burner head conduits positioned within the interior cavity in the lower portion of the housing, each of the conduits having a plurality of orifices, the orifices being oriented to create a vortex of gas movement;

an ignition system to ignite gas emitted from the orifices to form high intensity flames;

a primary source of forced air having a radial air supply conduit associated with each burner head conduit, each radial air supply conduit being adapted to create a vortex of air movement while delivering combustion air to a root of the flames of one of the burner head conduits; and

a secondary source of forced air having associated air supply outlets adapted to create a vortex of air movement while delivering air to a tip of the flames to minimize oxide formation.

2. The gas phase thermal unit as defined in claim 1, further comprising a sub-floor, insulated or non-insulated, to shield direct radiant heat energy from the burner to the controls/instruments and operators which can potentially cause damage to the equipment and injuries to the operators.

3. The gas phase thermal unit as defined in claim 1, wherein the housing is insulated with thermal insulation.

4. The gas phase thermal unit as defined in claim 3, wherein the insulation is ceramic fibre insulation.

5. The gas phase thermal unit as defined in claim 1, wherein the housing has a top and a bottom, the bottom being mounted on a skid, the skid being of sufficient weight to support the housing in a free standing vertical orientation.

6. The gas phase thermal unit as defined in claim 1, wherein the upper portion of the housing being of a length adapted to conceal any visible flame.

7. The gas phase thermal unit as defined in claim 1, wherein a laydown skid is provided for purpose of transport, the laydown skid extending along the housing.

8. The gas phase thermal unit as defined in claim 1, wherein a gas inlet extends from below up to a manifold which supplies gas to the radial burner head conduits.

9. The gas phase thermal unit as defined in claim 8, wherein a liquid separation chamber underlies the manifold, the liquid separation chamber being adapted to contain liquids carried in the gas, the liquids separated by means of centripetal force into the base of the liquid separation chamber.

10. The gas phrase thermal unit as defined in claim 1, wherein a low pressure vent line extends from the exterior of the thermal unit to the lower portion of the housing for venting low pressure gas collected from portable tanks regularly associated with drilling and well testing procedures.