# US 4,392,529 A · Method of cleaning a well and apparatus thereof > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 4,392,529 A - Document ID: US4392529A - Status: Granted - Kind: A - Application number: 06/317,750 - Filed: 1981-11-03 - Granted: 1983-07-12 - Earliest claimed: 1981-11-03 - Inventors: Maurel R. Burwell - Web page: https://patentgrep.com/patent/US4392529A ## CPC - E21B 37/08: cleaning in situ of down-hole filters, screens, {e.g. casing perforations,} or gravel packs (E21B37/06 takes precedence) - E21B 37/00: Methods or apparatus for cleaning boreholes or wells (E21B21/00 takes precedence) - E21B 37/06: using chemical means for preventing or limiting {, e.g. eliminating,} the deposition of paraffins or like substances - E21B 47/047: Liquid level (measuring depth or liquid level using radioactive markers E21B47/053) - E21B: EARTH OR ROCK DRILLING; OBTAINING OIL, GAS, WATER, SOLUBLE OR MELTABLE MATERIALS OR A SLURRY OF MINERALS FROM WELLS ## Abstract An improved method for cleaning a water well by creating a pulsating action at the lower inlet end of the well casing. The well casing is sealed to form a generally airtight enclosure. A water level sensing probe is placed within and extends generally throughout the casing. A vacuum is formed in the well casing by pumping the air therefrom which raises the water column within the casing to a predetermined height. The water level sensing probe signals the height of the water column as it rises within the casing. The vacuum is destroyed upon the water column reaching a predetermined height and the weight of the descending water column forces the water outwardly through the casing openings and into the surrounding strata. The raising and lowering of the water column by creating and destroying a vacuum is repeated, causing an incoming and outgoing surging action of water at the lower end of the casing to remove material blocking the inlet openings and to rearrange the bed of gravel and sand surrounding the openings. The apparatus for carrying out the cleaning operation is relatively lightweight and portable and includes an electrical vacuum-producing pump, an electrical water level sensing probe and indicating lights for the probe, and a dc voltage system for the probe and for applying an electrical charge to the casing to assist in the destruction of the encrustations at the bottom of the casing by creating an electrolytic action. ## Claims ### Claim 1 An improved method of cleaning a well including the steps of: (a) sealing the well casing to form a generally air-tight enclosure therein; (b) forming a vacuum within the well casing enclosure by pumping the air therefrom to raise a column of water within the well casing enclosure to a predetermined height; (c) destroying the vacuum formed in the well casing enclosure causing the raised water column to drop downwardly forcing the water out through inlet openings adjacent the bottom of the well casing and into the surrounding strata to remove encrustations and obstructions blocking the inlet openings; and (d) repeating the raising and lowering of the column of water in the well casing enclosure by creating a vacuum therein and destroying the same to clean the well casing openings and surrounding strata. ### Claim 2 (depends on 1) The method defined in claim 1 including the steps of placing a chemical solution in the water in the well casing enclosure to assist the destruction of encrustations on the well casing. ### Claim 3 (depends on 2) The method defined in claim 2 in which the chemical solution is chlorine. ### Claim 4 (depends on 1) The method defined in claim 1 including the step of inserting water level indicating means into the well casing enclosure to detect the level of the water column therein. ### Claim 5 (depends on 4) The method defined in claim 4 in which the water level indicating means provides a series of visual signals, each signal indicating a different height of the water column in the well casing enclosure. ### Claim 6 (depends on 5) The method defined in claim 5 in which the water level indicating means is initially lowered to the static level of the water column and then raised to a predetermined position above said static level before forming the vacuum within the casing enclosure. ### Claim 7 (depends on 1) The method defined in claim 1 including the step of applying a dc voltage of a certain polarity to the well casing to create an electrolytic action for accelerating the breakdown of encrustations on the well casing. ### Claim 8 (depends on 1) The method defined in claim 1 including the steps of providing a storage tank communicating with portions of the vacuum-forming apparatus; and creating a vacuum in the storage tank at the start of a well cleaning operation and maintaining said vacuum in the tank throughout the cleaning operation. ### Claim 9 (depends on 1) The method defined in claim 1 in which the vacuum within the well casing enclosure is destroyed automatically upon the water column reaching a predetermined height in the casing by actuating an electrical circuit which operates a valve to vent the well casing enclosure to the atmosphere. ### Claim 10 (depends on 1) The method defined in claim 1 including the step of periodically removing the water column from a portion of the well casing enclosure and providing a fresh column of water in the casing enclosure from the surrounding strata. ### Claim 11 A system for rejuvenating a well including: (a) means for sealing the upper end of a well casing for forming a generally airtight enclosure therein; (b) water level sensing means located within the well casing for indicating the level of a water column in the casing enclosure; (c) pump means communicating with the well casing enclosure for removing the air therefrom to form a vacuum to raise the level of the water column in the casing enclosure; (d) means for destroying the vacuum upon the water reaching a predetermined height in the casing enclosure, whereupon the water column will descend and the water will flow outwardly through water inlet openings at the bottom of the well casing for unblocking said openings; and (e) means for actuating the pump means upon the water column dropping to a predetermined lower level for creating another vacuum in the casing enclosure to raise the water column by drawing water into the casing through the inlet openings from the surrounding strata to further unblock said openings and rejuvenate the surrounding strata. ### Claim 12 (depends on 11) The system defined in claim 11 in which the water level sensing means includes a plurality of electrical conductors extending downwardly into the well casing enclosure with certain of said conductors being connected to separate contactors located at spaced intervals along the casing enclosure whereby the water will complete an electrical path between certain of the contactors upon the water level reaching said certain contactors. ### Claim 13 (depends on 11) The system defined in claim 11 in which auxiliary storage chamber means communicates with the pump means for forming a vacuum in said chamber means prior to forming a vacuum in the casing enclosure to check for air leaks and assist the sealing means on the upper end of the casing to form a generally airtight enclosure in the well casing. ### Claim 14 (depends on 11) The system defined in claim 11 in which one terminal of a dc power supply is connected to an electrode which is connected to the well casing to create an electrolytic action to assist in decomposing encrustations formed on the well casing. ### Claim 15 (depends on 11) The system defined in claim 11 in which pressure indicating means communicates with the pump means and well casing enclosure to provide a visual reading of the pressure in the casing enclosure. ### Claim 16 (depends on 11) The system defined in claim 11 in which the pump means is connected to the well casing enclosure by an air line; in which first solenoid-activated valve means is connected to the air line for opening and closing said air line; and in which the first valve means is in an open position when a vacuum is formed in the well casing enclosure. ### Claim 17 (depends on 16) The system defined in claim 16 in which the means for destroying the vacuum includes a vent line communicating with well casing enclosure and the atmosphere, and a second solenoid-actuated valve means for opening and closing said vent line; and in which the second valve means is moved to an open position to vent the well casing enclosure to the atmosphere to destroy the vacuum. ### Claim 18 (depends on 11) The system defined in claim 11 in which the sealing means is a pad of resilient material adapted to be placed on an open top of the well casing.