GB2069617A

GB2069617A - A borehole water extractor

Info

Publication number: GB2069617A
Application number: GB8004478A
Authority: GB
Original assignee: Individual
Current assignee: Individual
Priority date: 1980-02-11
Filing date: 1980-02-11
Publication date: 1981-08-26

Abstract

A water extractor has a receiving chamber 8 and a non-return 7 arranged to permit flow of water into the receiving chamber 8. A delivery pipe 2 extends from the receiving chamber 8. A pressure pipe 1 communicates with the receiving chamber 8 for supplying pressurized gas to the receiving chamber 8 to drive water out of the chamber through the delivery pipe 2. <IMAGE>

Description

SPECIFICATION A borehole water extractor The present invention relates to a borehole water extractor. The extractor is particularly though not exciusively suitable for use in extracting water from boreholes drilled in a quarry face for explosive blasting.

Such holes may fill with rain water which necessitates the use of waterproof explosive unless the water is extracted. Waterproof explosive is more expensive than standard explosive. In the past water has been extracted by passing a tube down the hole in question and blowing compressed air down the tube to drive the water out. This crude system is not readily controllable and can result in stones dislodging from the bore hole walls which can result in the hole collapsing.

The water extractor of the invention comprises a receiving chamber, an inlet non-return valve arranged to permit flow of water into the receiving chamber, a delivery pipe extending into the receiving chamber, and a pressure pipe communicating with the receiving chamber for supplying pressurized fluid to the receiving chamber to drive water, which has flowed into the chamber via the non-return valve, out of the chamber through the delivery pipe.

The method of water extraction consists of introducing the extractor into the borehole at least far enough for the mouth of the delivery pipe to be below the water level in the borehole, allowing water to flow via the non-return valve into the receiving chamber and supplying pressurized fluid to the receiving chamber to drive water out of the chamber through the delivery pipe. Normally it will be necessary to repeat the process a number of times until sufficient water has been extracted to lower the water level in the bore hole to the level of the mouth of the delivery tube.

Conveniently compressed air is used as the pressurized fluid. A large volume flow of air is not required to deliver the water. Each time water ceases to be delivered, the compressed air is vented to allow the receiving chamber to refill. Thus the water flows from the borehole in a steady controlled manner.

Preferably a three-way valve is connected between the pressure pipe and the source of compressed air for alternately pressurizing and venting the pressure pipe. The valve may be automatically actuated either to vent for a given length of time after water ceases to be delivered and then to repressurize or where the valve is a rotary valve, it may be rotated at a steady rate to provide alternate pressurization and venting for fixed periods.

The delivery pipe and the pressure pipe may be separate, but are preferably arranged coaxially with the delivery pipe within the pressure pipe. Although a separate receiving chamber may be provided, it is convenient for the chamber to consist of a portion of the pressure pipe. To facilitate handling the pipes are usually of flexible material. An inlet filter is normally provided.

To help understanding of the invention, a specific embodiment will now be described by way of example with reference to the accompanying drawing which illustrates a side view, partly in section, of an extractor in accordance with the invention.

The illustrated extractor has a 1 > " inch pressure pipe 1 and -" delivery pipe 2 within the pressure pipe 1, both of which are of flexible plastics material and 100' long. At the foot of the extractor a brass valve housing 3 is fitted to the end of the pressure pipe. Initially the housing 3 will be below the water level 4 in the borehole 5. Water can flow in via an inlet filter 6 incorporated in the housing and an inlet non-return valve 7. A receiving chamber 8, in effect formed by the pressure pipe 1 and the portion of the housing 3 above the valve, fills with water until, as shown, the level in the chamber and in the borehole is equal. The mouth 9 of the delivery pipe 2, which is located by an apertured spacer ring 10, is below the water level.

At the upper end of the extractor a fitting 11 in the end of the pressure pipe 1 seals around and passes the delivery pipe 2 out of the pressure pipe 1. The fitting also provides a connection 1 2 for an air line 1 3 from a compressor 1 4. In the air line 1 3 a three-way valve 1 5 is arranged for alternate pressurization and venting of the pressure pipe 1.

Once water has flowed into the receiving chamber with the three-way valve 1 5 in its venting position, as shown, the valve is turned to pressurize the pressure pipe 1 with compressed air. This acting on the water in the receiving chamber drives the water up the delivery pipe 2 to the outlet 1 6. Once air issues from the outlet 16, the valve 1 5 is returned to its venting position and the process is repeated until the water level is brought down to the level of the mouth 9 of the delivery tube.

To help feeding of the extractor into the borehole a short tubular steel liner 1 7 welded to a piatform 1 8 is fed into the top of the borehole.

It is envisaged that the extractor may be used elsewhere than boreholes for blasting, for instance for extracting water from a well.

1. A water extractor comprising a receiving chamber, an inlet non-return valve arranged to permit flow of water into the receiving chamber, a delivery pipe extending from the receiving chamber, and a pressure pipe communicating with the receiving chamber for supplying pressurized gas to the receiving chamber to drive water, which has flowed into

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

Claims

**WARNING** start of CLMS field may overlap end of DESC **. SPECIFICATION A borehole water extractor The present invention relates to a borehole water extractor. The extractor is particularly though not exciusively suitable for use in extracting water from boreholes drilled in a quarry face for explosive blasting. Such holes may fill with rain water which necessitates the use of waterproof explosive unless the water is extracted. Waterproof explosive is more expensive than standard explosive. In the past water has been extracted by passing a tube down the hole in question and blowing compressed air down the tube to drive the water out. This crude system is not readily controllable and can result in stones dislodging from the bore hole walls which can result in the hole collapsing. The water extractor of the invention comprises a receiving chamber, an inlet non-return valve arranged to permit flow of water into the receiving chamber, a delivery pipe extending into the receiving chamber, and a pressure pipe communicating with the receiving chamber for supplying pressurized fluid to the receiving chamber to drive water, which has flowed into the chamber via the non-return valve, out of the chamber through the delivery pipe. The method of water extraction consists of introducing the extractor into the borehole at least far enough for the mouth of the delivery pipe to be below the water level in the borehole, allowing water to flow via the non-return valve into the receiving chamber and supplying pressurized fluid to the receiving chamber to drive water out of the chamber through the delivery pipe. Normally it will be necessary to repeat the process a number of times until sufficient water has been extracted to lower the water level in the bore hole to the level of the mouth of the delivery tube. Conveniently compressed air is used as the pressurized fluid. A large volume flow of air is not required to deliver the water. Each time water ceases to be delivered, the compressed air is vented to allow the receiving chamber to refill. Thus the water flows from the borehole in a steady controlled manner. Preferably a three-way valve is connected between the pressure pipe and the source of compressed air for alternately pressurizing and venting the pressure pipe. The valve may be automatically actuated either to vent for a given length of time after water ceases to be delivered and then to repressurize or where the valve is a rotary valve, it may be rotated at a steady rate to provide alternate pressurization and venting for fixed periods. The delivery pipe and the pressure pipe may be separate, but are preferably arranged coaxially with the delivery pipe within the pressure pipe. Although a separate receiving chamber may be provided, it is convenient for the chamber to consist of a portion of the pressure pipe. To facilitate handling the pipes are usually of flexible material. An inlet filter is normally provided. To help understanding of the invention, a specific embodiment will now be described by way of example with reference to the accompanying drawing which illustrates a side view, partly in section, of an extractor in accordance with the invention. The illustrated extractor has a 1 > " inch pressure pipe 1 and -" delivery pipe 2 within the pressure pipe 1, both of which are of flexible plastics material and 100' long. At the foot of the extractor a brass valve housing 3 is fitted to the end of the pressure pipe. Initially the housing 3 will be below the water level 4 in the borehole 5. Water can flow in via an inlet filter 6 incorporated in the housing and an inlet non-return valve 7. A receiving chamber 8, in effect formed by the pressure pipe 1 and the portion of the housing 3 above the valve, fills with water until, as shown, the level in the chamber and in the borehole is equal. The mouth 9 of the delivery pipe 2, which is located by an apertured spacer ring 10, is below the water level. At the upper end of the extractor a fitting 11 in the end of the pressure pipe 1 seals around and passes the delivery pipe 2 out of the pressure pipe 1. The fitting also provides a connection 1 2 for an air line 1 3 from a compressor 1 4. In the air line 1 3 a three-way valve 1 5 is arranged for alternate pressurization and venting of the pressure pipe 1. Once water has flowed into the receiving chamber with the three-way valve 1 5 in its venting position, as shown, the valve is turned to pressurize the pressure pipe 1 with compressed air. This acting on the water in the receiving chamber drives the water up the delivery pipe 2 to the outlet 1 6. Once air issues from the outlet 16, the valve 1 5 is returned to its venting position and the process is repeated until the water level is brought down to the level of the mouth 9 of the delivery tube. To help feeding of the extractor into the borehole a short tubular steel liner 1 7 welded to a piatform 1 8 is fed into the top of the borehole. It is envisaged that the extractor may be used elsewhere than boreholes for blasting, for instance for extracting water from a well. CLAIMS

1. A water extractor comprising a receiving chamber, an inlet non-return valve arranged to permit flow of water into the receiving chamber, a delivery pipe extending from the receiving chamber, and a pressure pipe communicating with the receiving chamber for supplying pressurized gas to the receiving chamber to drive water, which has flowed into the chamber via the non-return valve, out of the chamber through the delivery pipe.

2. A water extractor as claimed in claim 1 wherein the delivery pipe is arranged within the pressure pipe.

3. A water extractor as claimed in claim 2 wherein the receiving chamber, at least partially, consists of space outside the delivery pipe and within the pressure pipe.

4. A water extractor as claimed in claim 1 or claim 2 wherein the receiving chamber is separate from the pressure pipe.

5. A water extractor as claimed in any preceeding claim including a three-way valve arranged to alternatively vent the receiving chamber to allow water to flow in and to pressurize the receiving chamber to drive the water from the receiving chamber.

6. A water extractor as claimed in claim 5 including means for rotating the valve for automatically alternatively venting and pressurizing the receiving chamber.

7. A water extractor as claimed in any preceeding claim including a source of compressed air.

8. A water extractor as claimed in any preceeding claim including an inlet filler.

9. A water extractor as claimed in any preceeding claim wherein the delivery pipe and the pressure pipe are of flexible plastics material.

10. A water extractor as claimed in any preceeding claim including a metallic platform and depending metallic liner through which the delivery pipe and the pressure pipe can be fed into the top of a bore hole.

11. A water extractor substantially as hereinbefore described with reference to the accompanying drawings.

1 2. A method of extracting water from a bore hole consisting in the steps of introducing a water extractor as claimed in claim 1 into the borehole at least far enough for the mouth of the delivery pipe to be below the water level in the borehole, allowing water to flow via the non return valve into the receiving chamber and supplying pressurized gas to the receiving chamber to drive water out of the chamber through the delivery pipe.

1 3. A method of extracting water as claimed in claim 1 2 including the step of venting the gas pressure in the receiving chamber to allow more water to flow into the chamber and then alternatively supplying pressurized gas and venting it for extraction of further water.

14. A method of extracting water from a borehole substantially as hereinbefore described with reference to the accompanying drawing