GB2082928A - A fluid injector - Google Patents

Abstract

A fluid injector for injecting a first fluid into a second fluid comprises a first member (2), a second member (3) attached to the first member, a passageway (6) in the first member, and an outlet from the passageway which communicates with outlet pores from the injector formed due to surface irregularities at adjacent faces 14, 15 of the first and second members. <IMAGE>

Description

SPECIFICATION A fluid injector This invention relates to a fluid injector.

Fluid injectors are used, for example, to inject a gas into a liquid flow in order to effect absorption of the gas by the liquid, or absorption of an element in the liquid by the gas. The degree of such absorption is proportional to the contact area between the liquid and the gas, and the efficiency of the absorption can be shown to be inversely proportional to the size of the gas bubbles injected into the liquid.

Since: the surface area (A) of a sphere = #D2; and the volume (V) of a sphere = 7lDV6; then:

Thus, the smaller the diameter (D) of a gas bubble, the greater will be the contact area (A) for a a given volume of gas.

According to the invention there is provided a fluid injector for injecting a first fluid into a second fluid, the injector comprising a first member, a second member attached to the first member, a passageway in the first member, and an outlet from the passageway which communicates with outlet pores from the injector formed due to surface irregularities at adjacent faces of the first and second members.

The surface irregularities could be on a surface of the first member and/or on a surface of a second member.

The first and second members preferably have frusto-conical shapes.

the invention will now be described, by way of example, with reference to the accompanying drawings, in which: Figure 1 shows a side view of a gas injector according to the invention, superimposed on a side view of pipework in order to show the installed position of the injector in the pipework, and Figure 2 shows a detailed, sectional view of the injector shown in Figure 1.

Referring to Figure 1, the gas injector comprises a body member 1 which is attached to a supply tube 2. The body member 1 has a substantially conical shape and is attached, at its base surface, to one end face of a spool member 2 having a substantially frusto-conical shape. The other end face of the spool member 2, of smaller diameter than the side attached to the body member 1, is attached to a nose member 3 which also has a substantially frusto-conical shape. The gas injector is housed in pipework 4 in which a liquid is flowing. The flow direction of this liquid is indicated by arrows 5.

Referring to Figure 2, the body member 1 contains a central, coaxial inlet tube 6 which is attached to the supply tube 2 (not shown) and in which the direction of gas flow Is Indicated by arrow 7. The nose member 3 is screwed on to the inlet tube 6. In each of the end faces of the spool member 2 there is provided a respective distribution chamber, 8 and 9. The distribution chambers 8 and 9 are in communication with the inlet tube 6 via ports 10 and 1 1 respectively. The peripheries 12 and 13 of the respective end faces of the spool member 2, which peripheries 12 and 13 define the distribution chambers 8 and 9 respectively, provide contact surfaces 14 and 15 respectively with the body member 1 and the nose member 3 respectively.

In use, gas is supplied to the injector inlet tube 6 via the supply tube 2. This gas flows from the inlet tube 6 to the distribution chambers 8 and 9 via the ports 10 and 11 respectively. From the distribution chambers 8 and 9, the gas is forced into the liquid flowing pass the injector via the many small escape paths (not shown) formed at the contact surfaces 14 and 15 respectively because of irregularities in the rough surface finish of the body member 1, the spool member 2, and the nose member 3. The contact surfaces 14 and 1 5 thus act as dispersal faces for the gas, the gas flow being broken-up into a plurality of small bubbles by the plurality of resulting outlet pores.

The shape of the gas injector is such that the velocity of the liquid is effectively increased in the region of the contact surfaces 14 and 1 5, which facilitates a fine dispersal of the gas bubbles in the liquid.

Any number of contact surfaces (14 and 15) could be provided in the gas injector. The rate of gas flow through the gas injector is determined by the degree of roughness of the finish at the contact surfaces 14 and 15 and by the number of contact surfaces provided.

The surface finishes of the body member 1 and the nose member 3 could, for example, be relatively smooth, gas escape paths at the contact surfaces 14 and 15 being provided solely by a rough surface finish of the spool member 2.

1. A fluid injector for injecting a first fluid into a second fluid, the injector comprising a first member, a second member attached to the first member, a passageway which communicates with outlet pores from the injector formed due to surface irregularities at adjacent faces of the first and second members.

2. An injector according to Claim 1 , wherein the surface irregularities are on a surface of the first member and/or on a surface of the second member.

**WARNING** end of DESC field may overlap start of CLMS **.

Claims (4)

**WARNING** start of CLMS field may overlap end of DESC **. SPECIFICATION A fluid injector This invention relates to a fluid injector. Fluid injectors are used, for example, to inject a gas into a liquid flow in order to effect absorption of the gas by the liquid, or absorption of an element in the liquid by the gas. The degree of such absorption is proportional to the contact area between the liquid and the gas, and the efficiency of the absorption can be shown to be inversely proportional to the size of the gas bubbles injected into the liquid. Since: the surface area (A) of a sphere = #D2; and the volume (V) of a sphere = 7lDV6; then: Thus, the smaller the diameter (D) of a gas bubble, the greater will be the contact area (A) for a a given volume of gas. According to the invention there is provided a fluid injector for injecting a first fluid into a second fluid, the injector comprising a first member, a second member attached to the first member, a passageway in the first member, and an outlet from the passageway which communicates with outlet pores from the injector formed due to surface irregularities at adjacent faces of the first and second members. The surface irregularities could be on a surface of the first member and/or on a surface of a second member. The first and second members preferably have frusto-conical shapes. the invention will now be described, by way of example, with reference to the accompanying drawings, in which: Figure 1 shows a side view of a gas injector according to the invention, superimposed on a side view of pipework in order to show the installed position of the injector in the pipework, and Figure 2 shows a detailed, sectional view of the injector shown in Figure 1. Referring to Figure 1, the gas injector comprises a body member 1 which is attached to a supply tube 2. The body member 1 has a substantially conical shape and is attached, at its base surface, to one end face of a spool member 2 having a substantially frusto-conical shape. The other end face of the spool member 2, of smaller diameter than the side attached to the body member 1, is attached to a nose member 3 which also has a substantially frusto-conical shape. The gas injector is housed in pipework 4 in which a liquid is flowing. The flow direction of this liquid is indicated by arrows 5. Referring to Figure 2, the body member 1 contains a central, coaxial inlet tube 6 which is attached to the supply tube 2 (not shown) and in which the direction of gas flow Is Indicated by arrow 7. The nose member 3 is screwed on to the inlet tube 6. In each of the end faces of the spool member 2 there is provided a respective distribution chamber, 8 and 9. The distribution chambers 8 and 9 are in communication with the inlet tube 6 via ports 10 and 1 1 respectively. The peripheries 12 and 13 of the respective end faces of the spool member 2, which peripheries 12 and 13 define the distribution chambers 8 and 9 respectively, provide contact surfaces 14 and 15 respectively with the body member 1 and the nose member 3 respectively. In use, gas is supplied to the injector inlet tube 6 via the supply tube 2. This gas flows from the inlet tube 6 to the distribution chambers 8 and 9 via the ports 10 and 11 respectively. From the distribution chambers 8 and 9, the gas is forced into the liquid flowing pass the injector via the many small escape paths (not shown) formed at the contact surfaces 14 and 15 respectively because of irregularities in the rough surface finish of the body member 1, the spool member 2, and the nose member 3. The contact surfaces 14 and 1 5 thus act as dispersal faces for the gas, the gas flow being broken-up into a plurality of small bubbles by the plurality of resulting outlet pores. The shape of the gas injector is such that the velocity of the liquid is effectively increased in the region of the contact surfaces 14 and 1 5, which facilitates a fine dispersal of the gas bubbles in the liquid. Any number of contact surfaces (14 and 15) could be provided in the gas injector. The rate of gas flow through the gas injector is determined by the degree of roughness of the finish at the contact surfaces 14 and 15 and by the number of contact surfaces provided. The surface finishes of the body member 1 and the nose member 3 could, for example, be relatively smooth, gas escape paths at the contact surfaces 14 and 15 being provided solely by a rough surface finish of the spool member 2. CLAIMS

1. A fluid injector for injecting a first fluid into a second fluid, the injector comprising a first member, a second member attached to the first member, a passageway which communicates with outlet pores from the injector formed due to surface irregularities at adjacent faces of the first and second members.

2. An injector according to Claim 1 , wherein the surface irregularities are on a surface of the first member and/or on a surface of the second member.

3. An injector according to Claim 1 or 2, wherein the first and second members have frusto-conical shapes.

4. A fluid injector, substantially as herein described with reference to the accompanying drawings.