Abstract: There is disclosed an apparatus and method for drilling underground. The apparatus includes a conventional drilling bit and a shroud disposed around the drill bit to produce a confined for the suspension of drilling debris. The debris is withdrawn under suction from the area by a conduit system associated with the shroud and a cyclonic filter structure.

Abstract: Drill cuttings and similar earth materials are reduced in particle size, slurried and disposed of from a system which includes a ball mill, a reduced particle receiving tank, a grinder pump in communication with the receiving tank and separator screens for receiving a slurry of particles which have been reduced in size through the ball mill and the grinder pump. The underflow of the separator is suitable for discharge for final disposal, oversized particles are returned to the ball mill and the underflow discharged from the separator is controlled to maintain a certain level in the primary receiving tank. A secondary tank may receive a portion of the underflow to be mixed with viscosifiers and dispersants to maintain a suitable slurry composition for discharge. The system may be mounted on a semi-trailer and in weather-proof enclosures with the ball mill, receiving tanks and grinder pump on a first level and the separators on a second level.

Abstract: The invention is an apparatus for mixing and injecting into a well tubular a dry material/liquid slurry. The apparatus is comprised of an entrainment chamber having an inlet and an outlet, a hopper having an inlet, and an outlet detachably connected to the chamber inlet, a jet nozzle vertically positioned adjacent the hopper outlet and a tubing connector attached to the chamber outlet. Pressurized liquid is passed through the jet nozzle creating a partial vacuum, entraining gravity fed material from the hopper to form a slurry. The slurry passes through the tubing connector and is injected into a well tubular which are detachably connected to the tubing connector.

Abstract: Drill cuttings are cleaned of oil-based drilling mud and oil using a cleansing agent, such as a C6-C10 carboxylic acid, that is preferentially oil soluble at one pH and preferentially water soluble at another pH. The oily cuttings are treated with the carboxylic acid and then washed with an aqueous, alkaline washing solution, which converts the carboxylic acid to its water soluble salt and, with vigorous agitation, lifts most of the oil from the cuttings. In other embodiments, the process is used for cleaning oil-contaminated soil, sand, and gravel, and for separating the oils from the solids in oily sludges.

Abstract: Drill cuttings are cleaned of oil-based drilling mud and oil using a cleansing agent, such as a C6-C10 carboxylic acid, that is preferentially oil soluble at one pH and preferentially water soluble at another pH. The oily cuttings are treated with the carboxylic acid and then washed with an aqueous, alkaline washing solution, which converts the carboxylic acid to its water soluble salt and, with vigorous agitation, lifts most of the oil from the cuttings. In other embodiments, the process is used for cleaning oil-contaminated soil, sand, and gravel, and for separating the oils from the solids in oily sludges.

Abstract: Drilling mud is economically disposed of in an environmentally sound manner by mixing the mud with a crosslinkable polymer and a crosslinking agent to form a composition that solidifies at a predetermined time. The composition is injected into a subterranean formation through an abandoned well and, when solidified, is substantially immobilized within the formation.

Abstract: An improved gas trap for mud logging is vertically mounted such that its lower end is constantly beneath the surface of mud flowing in a tank. The mud is drawn into the housing where it is agitated to release the entrained gases which are drawn off for measurement. The spent mud is returned to the tank through a mud exit port and related pipe to a point below the level of the mud and remote from the mud intake to the gas trap. This gas trap is insensitive to mud level changes and is relatively free of maintenance requirements.

Abstract: New apparatii and processes are disclosed to create fluid continuity between opposite ends of a route drilled or bored under and/or around an obstacle. This invention allows fluids to be pumped through a reamer and a hollow swivel from either or both sides of the obstacle. It also allows the direct transfer of fluids from one side to the other through the connecting conduit located in the annular space produced during drilling and reaming operations.

Abstract: Drill cuttings are cleaned of oil-based drilling mud and oil using a cleaning agent, such as a C6-C10 carboxylic acid, that is preferentially oil soluble at one pH and preferentially water soluble at another pH. The oily cuttings are treated with the carboxylic acid and then washed with an aqueous, alkaline washing solution, which converts the carboxylic acid to its water soluble salt and, with vigorous agitation, lifts most of the oil from the cuttings. In other embodiments, the process is used for cleaning oil-contaminated soil, sand, and gravel, and for separating the oils from the solids in oily sludges.

Abstract: A method of recycling or destroying the components of viscous oil well drilling mud and saltwater which includes reducing the mud to an aqueous slurry; separating and collecting the useable hydrocarbons from the slurry by evaporation or chemical action; injecting deleterious substances including saltwater into an environmentally approved injection well; and or forming fertilizer pellets from remaining dehydrated solids.

Abstract: Drill cuttings are disposed of by injection into a subsurface formation by way of an annular space formed in a wellbore. The cuttings are removed from the drilling fluid, conveyed to a shearing and grinding system that converts the cuttings into a viscous slurry with the addition of water. The system comprises a receiving tank and a centrifugal pump for recirculating the mixture of cuttings and water (seawater) between the pump and the receiving tank. A discharge conduit is connected to the pump for moving the viscous slurry to an injection pump for high pressure injection into the formation.

Abstract: In a drilling system where production fluids are produced during the drilling operation, a brine solution is used to prevent development of a filter cake on the formation and thereby in the absence of such filter cake, allow production to occur. A separation system at the surface separates out the gas component of the produced fluids, the fluidized particulate drill cuttings, and produced oil, to return a reusable drilling fluid to the system, which drilling fluid is substantially depleted of hydrocarbons so as to make the fluid usable. The separation system uses a hydrocyclone for processing an oily water phase to thereby minimize the complexity and cost of the oil/water separation portion of the drilling fluids system.

Abstract: Drill cuttings are disposed of by injection into a subsurface formation by way of an annular space formed in a wellbore. The cuttings are removed from the drilling fluid, conveyed to a shearing and grinding system that converts the cuttings into a viscous slurry with the addition of water. The system comprises a receiving tank and a centrifugal pump for recirculating the mixture of cuttings and water (sewater) between the pump and the receiving tank. A discharge conduit is connected to the pump for moving the viscous slurry to an injection pump for high pressure injection into the formation.

Abstract: A system for cleaning solids contaminated with solvent-soluble contaminants. The system comprises the use of at least two successive cleaning zones, each of which includes a slurry stage and a centrifuge separation stage, wherein the solids to be cleaned and the solvent used for cleaning flow in countercurrent relationship to each other between the successive zones.

Abstract: The invention is directed to a method and apparatus for removing oil base drilling mud or like contaminants from drill cuttings. A continuous phase liquid, such as, base oil or wash water, is used to wash the contaminants from the cuttings. The continuous phase liquid and the contaminants removed from the cuttings are separated for recirculation and reuse. The separation system (10) of the invention includes a wash drum (14) for agitating the contaminated cuttings and continuous phase liquid together, a drying screen (16) for separating the larger solids from the liquid phase, a first column tank (18) and a pair of centrifuges (24 and 26) for separating the smaller solids from the liquid phase, and second and third column tanks (20 and 22) for separating the continuous phase liquid from the removed contaminants.

Abstract: A system for cleaning solids contaminated with solvent-soluble contaminants. The system, which includes both process and apparatus, comprises slurrying of the solids with a solvent, feeding the slurry to a cyclone separation zone integrally connected to a countercurrent extraction zone, separating the slurry into an overflow stream which includes solvent and fine particles of solids and an underflow stream which includes mostly coarse particles of solids in the cyclone separation zone, processing the overflow stream in a cleaning zone with additional solvent, processing the underflow stream in countercurrent relationship with additional solvent through the countercurrent extraction zone, combining the cleaned coarse particles of solids withdrawn from the extraction zone with the cleaned fine particles of solids withdrawn from the cleaning zone and centrifuging the combined cleaned particles to remove residual solvent and recovering the combined solids having reduced contamination for disposal.

Abstract: An excavation apparatus includes a suction system with a suction tank pneumatically connected to a blower through a filter subassembly. A suction hose is pneumatically connected to the suction tank. A liquid jet system includes a liquid reservoir fluidically connected to a liquid pump, which in turn is fluidically connected to a spray wand. The suction and liquid jet systems are mounted on a vehicle. An excavation method includes the steps of dislodging earthen material with a liquid jet from the spray wand and sucking it into the suction tank with the suction system.

Abstract: A method of receiving returns from a well being drilled in which the hydrostatic pressure of the drilling fluid cannot contain the formation pressure and controlling the flow and pressure of the returns and separating the oil, gas, and drilling fluids on the surface and returning the drilling fluids to the well while disposing of the oil and gas.

Abstract: The present invention is a gas sampling device. A gas sampling tube and pump withdraw gas which evolves into the atmosphere as the drilling fluid in the annular space exits the wall bore. Drilling fluid and debris which may be entrained in the gas sample are separated by gravity settling in a separation device. A purge line may be used to agitate drilling mud and force gas toward the gas sampling tube.

Abstract: A method and apparatus for deoxidation of water uses a catalytic combustion chamber in which a fuel having a low ignition temperature is first delivered during a start-up phase in order to begin ignition. The fuel used for start-up may, for example, be vaporized methanol or hydrogen. After an interval of time, the fuel supplied is continuously throttled and, at the same time, an operational fuel having a higher ignition temperature is supplied in increasing quantities until the stripping gas reaches a required temperature. On completion of the start-up phase, only the operational fuel which consists of, or least contains natural gas as a component, is then fed to the catalytic combustion process.

Abstract: A subsea storage structure for treatment and storing drill cuttings from drilling operations in the sea bottom includes a generally closed container or tank suitable to be positioned on the sea bottom near the drilling site, which tank is provided with an upper inlet for supply of drill cuttings, and an output to ambient water for water which is displaced during the supply of drill cuttings. The tank contains arrangements for cleansing of the drill cuttings and storage of accumulated oil, fluids and other constituents separated from the drill cuttings, and structure for extraction of the accumulated oil, fluids and other constitutents lighter than water.

Abstract: Drilling cuttings comprising usable gravel, silts, clays and spent drilling fluid are reclaimed and disposed of during or after the process of drilling a well by separating construction-grade gravel from the drilling fluid and washing the gravel, if necessary, prior to storage or placing it in use as construction material. Solids not reclaimed for construction use are formed as a slurry and conducted to an injection well by and through centrifugal pumps or mechanical agitators for dispersing the fine solids in the slurry to aid in the injection process. Gravel wash water may be used as a component of the waste slurry and the slurry may be conditioned for injection by the addition of surfactants and dispersants.

Abstract: A solids flow distribution apparatus is disclosed for use with two or more solid separation devices, such as shale shakers. The appartatus includes a plenum in communication with a source of flow of solids and liquid, such as from a drilling rig's mud system. The plenum includes lower outlets positioned adjacent inlet zones for each solid separation device. Valves are positioned across the lower outlets for regulating the quantity of solids and liquids that flow into the inlet zones of each solid separation device. A variable distribution apparatus is included within the plenum adjacent the flow inlet for regulating the proportion of solids directed towards each solid separation device.

Abstract: A multi-conduit tubular having fluid conduits (30) and electrical conduits (108), with associated surface fluid (182) and electrical (186) commutators, and downhole sensors (18, 20, 290) for providing surface monitors (22) with instantaneous formation data. Each tubular (50) includes a plurality of uniform linear conduits (30) therethrough, with a gasketed seal plate (86) interposed between joined tubulars for assuring a high pressure seal between joined conduits. The seal plate (86) includes an intermediate electrical connector (126) for connecting electrical conduit connectors (116) of one tubular to another. A coupling collar (84) with uniform diameter internal coarse and fine threads (92, 94) joins the tubular ends having similar threads by differential thread action without respective tubular rotation.

Abstract: Method and apparatus for separating and recovering a granulate from a viscous suspension containing the graulate. The suspension is placed in a layer on an endless sieve belt guided around return rollers and effecting a separation into a sieve residue of the granulate which remains behind on the belt, and a stream of material passing through the belt. The stream of material is collected between the forward and backward runs of the sieve conveyor belt. The separated granulate is dumped from the conveyor belt. As the layer of the granulate containing suspension is dispensed on the sieve conveyor belt, at least one free edge extending across the sieve conveyor belt is formed and maintained. A stream of air passes downwardly through the sieve conveyor belt.

Abstract: A method and apparatus for drilling a wellbore in the earth from a location in a body of water wherein the drilling operation generates a substantial amount of a mixture of solid drilling cuttings, water, and at least one hydrocarbonaceous oil, wherein the water and oil are removed from the solid drilling cuttings so that the cuttings are put into a condition in which they can be disposed of in the body of water or elsewhere without adverse effects.

Abstract: A separation system for removing drilled solids from a drilling fluid being circulated in a well including a vibratory screen apparatus (10) and method for separating materials having a base (12) supporting a vibratory support frame (13) for relative vibratory movement. A pair of transversely aligned motor vibrators (88) are mounted on a transverse horizontal support (82) secured between opposed sides (64,66) of vibratory frame (13) generally in the area of the center of gravity of the vibratory from (13). The motor vibrators (88) have rotational axes (L3) extending at an angle A with respect to the horizontal and being in a vertical plane parallel to the longitudinal axis (L1) of the screen bed.

Abstract: A system for the quantitative analysis of one or more evolving gases exiting a borehole includes a Venturi ejector for substantially capturing liberated gases in the bell nipple and return line, a rotating disk extractor for substantially extracting gases entrained and dissolved in drilling mud, and a gas analyzer system for analyzing and quantifying the captured and extracted gases. The Venturi ejector preferably is operatively coupled to the return line, and a pipe wiper may be arranged to partially cover the bell nipple. The ejector sucks liberated gases out of the return line and causes a negative pressure to occur at the bell nipple such that air is sucked into the bell nipple rather than exiting the same. The rotating disk extractor has air flowing countercurrent to the mud flow. As the disks rotate, they pick up a thin liquid film of mud which is exposed to the air stream.

Abstract: Used drilling muds containing substantial quantities of organic liquids and water-soluble salts are treated to render them environmentally acceptable for disposal purposes, by drying the muds to evaporate all liquids, aqueous and non-aqueous, preferably in a shell-and-tube type heat exchanger through which they are conveyed and held in suspension by screw conveyors, and preferably with the vapors thus generated flowing in a direction counter-current to the mud. Water-soluble salts are removed from the dried mud components by dissolving with water, and the vapors are condensed and phase separated for further purification and re-use if desired.

Abstract: The mud of a drilling well is treated by injecting a liquid polymer chemical into the suction of a main circulating mud pump rather than by pouring the liquid chemical into the open collar of a drill pipe joint while making a connection. This causes the mud to exhibit lower gel strengths and obtain a bore hole more nearly to gauge.

Abstract: Heavy hydrocarbon containing sludges such as refinery waste streams, oil storage tank sludges and marine oil tanker ballast are treated by passing the sludges in a flow stream through an indirect dryer to vaporize liquids having a boiling point at atmospheric pressure of less than about 700.degree. F. and to provide substantially dried solid particles discharged from the dryer. The dried particles, containing heavy hydrocarbons as a coating or as a part of the solids, are conducted to a combustor/oxidizer and exposed to a high velocity flow stream of oxygen containing gas, typically low pressure forced air, to burn the residual hydrocarbons in the solids and to reduce heavy metals and the like to oxides thereof. A sludge handling system includes a rotary disk type indirect dryer connected to a lift pipe type combustor/oxidizer for thorough exposure of the dried solids to an oxygen containing atmosphere.

Abstract: The present invention provides a facile method of oil removal from an oil-water emulsion containing suspended solid particulates. In general, the method utilizes a volatile solvent which is liquefied under pressure and forms a two-phase system when in contact with the emulsion.

Abstract: A system is provided for the optimization of particle separation in a shaker system of a well drilling system. A well bore is drilled with a rotary drilling system. A stream of drilling fluid is circulated through the rotary drilling system to carry rock particles away from the bottom of the well bore as the well bore is formed. This stream of drilling fluid with the rock particles being carried therein is passed through a shaker system for separating the rock particles from the drilling fluid. A value of at least one, and preferably a plurality of operating parameters of the rotary drilling system are monitored, which parameters correlate to an average size of the rock particles being generated. The shaker system is adjusted in response to these monitored values, and more particularly in response to control signals computed based upon these monitored values, to increase separation of the rock particles by the shaker system.

Abstract: The enchancement of rock drilling by neutralizing the rock surface charge with respect to the drilling fluid. The isoelectric condition is obtained by nullifying the zeta potential of the rock surface by chemical additives such as surfactants or any material. Drilling enchancement is maintained as long as the rock zeta potential registers a zero reading. An apparatus and method is disclosed herein to achieve and maintain this isoelectric condition and provide for the maximal drilling rate and drill bit life.

Abstract: Drill cuttings, and similar slurries or mixtures oily solid particles, are treated by a dryer apparatus which vaporizes the liquid and discharges relatively large solid particles for disposal. Vapor and entrained solid fines are conveyed from the dryer to a condenser and then to a rotary drum vacuum filter having a precoated filter media disposed thereon. The solid fines are filtered by the filter media comprising diatomaceous earth or perlite and the clarified condensed liquid is conveyed to separator means for separating oil, water and any other liquids present. The filter media stripped from the filter and contaminated with entrapped solid fines is conveyed through the dryer means and disposed with the solids particles being discharged from the dryer.

Abstract: A mud cleaning system for recovering barite from drilling mud coming from an oil well, the mud being made up essentially of barite particles having a specific gravity of 4.2 or more, and a particle size mostly finer than 200 mesh, drill cuttings having a specific gravity of 2-3, and varying particle sizes ranging from about 200 mesh to 1/2 inch or more, and water. This system includes a first sieve bend (32), a second screen member (10) in series therewith, and a spiral separator (54), in series with the screens. The sieve bend is provided with a vibrator (18, 20), and water sprays (16, 34) act in conjunction with the sieve bend and the second screen to aid in the separation. The slurry leaving the spiral separator is screened to remove the ultra fine particles and the water is recycled. The system inherently washes potentially environmentally hazardous substances off the drill cuttings prior to their discharge from the system.

Abstract: A method and apparatus for drilling a wellbore in the earth from a location in a body of water wherein the drilling operation generates a substantial amount of a mixture of solid drilling cuttings, water and at least one hydrocarbonaceous oil wherein the water and oil are removed from the solid drilling cuttings and any retain solid particles in said water and oil are removed therefrom prior to reuse, disposal, or other disposition of said water and oil.

Abstract: Apparatus and method for removing combustibles from drill cuttings are provided wherein the drill cuttings are forced under pressure through an extrusion section having no moving parts. The extrusion section comprises a fixed mandrel coaxial with an outer cylindrical shell and having a thin annular chamber therebetween for heating the drill cuttings passing through the extrusion section. The drill cuttings then enter a separating means for removing the volatile combustibles from the solid drill cuttings.

Abstract: Apparatus for dehydrating slurries such as water based drilling fluids heavily laden with drill cuttings and other earth solids comprising a rotating drum which is heated by combustion of a fuel air mixture to generate relatively large quantities of combustion products for heating in an enclosed chamber defined by said drum. The slurry to be dehydrated is injected into the interior of the drum or against the outer sidewall thereof for rapid exposure and substantially flash evaporation of the slurry liquids. An outer housing may be constructed around the drum and in one embodiment the drum is arranged inclined to the horizontal with the slurry introduced into the interior of the drum and the combustion chamber formed between the outer housing and the drum. In another embodiment the combustion chamber is formed on the interior of the drum and the evaporation chamber is formed between the drum and the outer housing.

Abstract: An apparatus for removing fluids and hydrocarbons in oil well drill cuttings and an apparatus adapted to cooperate with conventional rig shakers for removing a major portion of fluid in the cuttings solids. A major portion of the fluids is removed by shaking the fluids-solids mixture. The solids are agitated by a chemical solution facilitating chemical removal of hydrocarbons in the solids. The solids are placed in an apparatus which shakes the solids at a higher speed than the first shaking, further separating fluids from solids. Fine particles of solids are removed from centrifuging. The separated solids are then discharged from the apparatus for disposal.

Abstract: A packaged, transportable waste treatment system for hazardous and non-hazardous wastes comprises a pair of mixing tanks having a flow inlet at the lower bottom central portion of the tanks, the flow inlet providing an injection conduit which proceeds vertically a distance into one of the tanks. A floc concentration tube is provided with an inner bore, the tube being vertically mounted in the tank about the injection conduit with the tube having a lower fluid inlet and an upper fluid outlet, the fluid inlet being in communication with the tank by means of a plurality of perforations in the tube at the fluid inlet adjacent the bottom of the tank. A rotatable propeller shaft having a mixing propeller mounted thereon is attached to the tank structure, the shaft being mounted at least in the tube bore above the injection conduit with the propeller being between the lower fluid inlet and the upper outlet immediately adjacent the outlet of the injection conduit.

Abstract: A chemical mixing apparatus comprises a preferably cylindrical mixing tank having a flow inlet at the lower bottom central portion of the tank, the flow inlet providing an injection conduit which proceed vertically a distance into the tank. A floc concentration tube is provided with an inner bore, the tube being vertically mounted in the tank about the injection conduit with the tube having a lower fluid inlet and an upper fluid outlet, the fluid inlet being in communication with the tank by means of a plurality of perforations in the tube at the fluid inlet adjacent the bottom of the tank. A rotatable propeller shaft having a mixing propeller mounted thereon is attached to the tank structure, the shaft being mounted at least in the tube bore above the injection conduit with the propeller being between the lower fluid inlet and the upper outlet immediately adjacent the outlet of the injection conduit.

Abstract: A water-based drilling fluid preparation system having an enclosed mixing chamber, a salt barrel, and piping means for selectively directing fluids exiting the mixing chamber means through the salt supply and to and from a suction pit. The mixing chamber has a first inlet for supplying a first fluid, such as drilling muds, into the mixing chamber, a second inlet for supplying water into the mixing chamber, and a third inlet means for supplying a heated fluid into the mixing chamber, wherein the drilling fluids are mixed in a selectively heated environment.

Abstract: The invention is a system which separates and reclaims a gas, e.g. methane, an aqueous fluid, e.g. water, and solids, e.g. coal from a slurry mixture. One application of the invention is in the degasification operations of underground mining. The system is hermetically constructed for the safe separation, collection and reclamation of the various components of the mixture.

Abstract: An "L" shaped mud pit longitudinally and horizontally hinges at an upper edge of a wall panel thereof to a portion of a vehicle frame, or an extension thereof, such that when lowered it is in ground-supported, horizontal position convenient with respect to the hole to be drilled and when raised it is in a storage-transport vertical position in which it is in line with the adjacent side of the vehicle, and its rearward portion is above the vehicle rear tire. A centrally located divider wall panel enables liquid to travel from the rear of the mud pit forward and then back again to the rear thereof where a removable extension to the mud pump intake pipe is located. Screens, adjustable leveling pads, and drain and cleanout plugs are also provided.

Abstract: A gas-liquid-solids separation system for use with a drilling device includes a surge tank for holding drilling efflux comprising gas, liquid and solids, and adapted for mounting on a drilling device in a position for having a drill shaft extending therethrough. A stuffing box attached to a back side of the surge tank means and configured for enabling passage of the drill shaft therethrough prevents the drilling efflux from escaping the surge tank. A flange attached to the front side of the surge tank and aligned with the stuffing box for allowing passage of the drill shaft therethrough provides a seal between the surge tank and a borehole casing to enable the drilling efflux to flow into the surge tank means. An agitator disposed within the surge tank maintains suspension of the solids within the liquid, and a gas cyclone in fluid communication with the surge tank withdraws gas from the surge tank and separates any entrained liquid therefrom.

Abstract: A system for treating oil-contaminated drill cuttings includes a grinder for increasing the surface area of the drill cuttings to enhance the absorption of free oil on the cuttings. A mixer enhances the absorption of free oil into the additional solid, oil-absorbent material exposed through the increased surface area of the ground cuttings. After mixing, the ground cuttings may be compacted into individual masses of sufficient density to sink in water. Fine materials are separated from said compacted masses prior to disposal in a marine environment.

Abstract: A portable well drilling mud storage and recirculation unit includes a mud storage tank mounted on an over-the-road semi-trailer having an engine driven circulating pump mounted onboard and adapted to withdraw mud from the tank for circulation to the well and for recirculation through a set of mud agitating nozzles disposed in the bottom of the tank. A mud degassing vessel, a solids separator unit and an additive blending unit are all mounted above the tank. The degassing vessel is supported by hydraulic cylinder actuators for movement between a retracted transport position and a vertically elevated working position.

Abstract: Method and apparatus for making a sharp separation of solids into components which are finer than the screen mesh and coarser then the screen mesh. The solids ladened fluid is introduced onto a screen to separate coarse solids from fine solids. A tray containing a body of aqueous liquid is vibrated causing the aqueous liquid to repeatedly contact the solids while on the screen to provide the needed mobility for fine particles to pass through the screen with the liquid. The aqueous liquid returns to the tray and the vibration of the tray aids in removal of the fine solids which have passed through the screen from the tray. Aqueous liquid is continuously added to the tray or sprayed above the screen to keep accumulated solids from increasing the viscosity of the aqueous liquid in the tray.

Abstract: In the separation of solids out of a flushing liquid such as used in flushing out boreholes and the like drilled or cut in rock, concrete, masonry and similar materials, a flocculant is added to the flushing liquid before it enters a settling tank so that the removal of the solids is accelerated. As a result, a supply of flushing liquid, free from solids, is always available from the settling tank. The flushing liquid flow is directed through the feed line into the settling tank. Before the liquid enters the settling tank it is passed in contact with a flocculant so that the liquid picks up a dosed quantity of the flocculant. To assure the optimum effect, after contacting the flocculant, the liquid is mixed and then passed into the settling tank.