Category Archives: Vacuum Degasser

Vacuum Degasser are used to remove the small entrained gas bubbles left in the mud by the mud/gas separator. These units are positioned downstream from mud/gas separators, shale shakers and mud cleaners, while hydrocyclones and centrifuges follow in the arrangement.

Working principle of vacuum degasser

The degassers are used to clean the gas in the drilling fluid, to ensure the drilling fluid property relatively stable, to guarantee the steady operation of swirlers. The degassers can be grouped into two kinds: ordinary pressure type and vacuum type. The ordinary pressure degasser is to use the centrifugal to take out gas to invade the mud, with the help of centrifugal force to make the mud spraying in the jet tanks and striking on the wall to make gas releasing. The vacuum degasser is to use the suction of the centrifugal, forming negative pressure in the vacuum tanks, under the action of drilling fluid at atmospheric pressure, through the suction pipe into the hollow shaft, then by umbrella piece of around the hollow shaft assembly, they jet to the skin of tank.

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Structure of vacuum degasser

ZCQ vertical type vacuum degasser made of explosion proof motor, vacuum pump, coaxial shunting gear reducer. When works, pressuring the start key, motor drive vacuum pump and mud gas separator degassing impeller rotate, gas cut invaded drilling fluid absorbed to mud gas separator and throw to mud gas separator by degassing impeller. Production a fluid lamina which is eddy spiral movement and form the centrifugal force field. Because the centrifugal force is the 32 times of its gravity, make the small bubbles in fluid lamina rapidly buoyancy lift to surface, in the function of negative pressure, the small bubbles rapidly broken, the broken bubbles gas enter into vacuum pump and discharged through the two air holes in reducer.

DC Solid Control is a total solids solutions provider. We offer industry leading solids control equipment including shale shakers, degassers, mud cleaners, deserter, desander and centrifuge. They are a complete circulating of mud systems.

vacuum degasserVacuum degasser use atmosphere and vacuum degassing theory eliminate the remaining gas in drilling fluid to ensure the drilling fluid property relatively stable, to guarantee the steady operation of swirlers. The degassers can be grouped into two kinds: ordinary pressure type and vacuum type.. Vacuum degasser tank is installed a group of wave blade and many mud inlet make flow is uniform distribution and form into turbulence in tank.

The vacuum degasser always set behind shale shaker. The internal impellers will mix the drilling fluid and break the bubble. It is a special-purpose device and a new type one for the treatment of gas in the drilling fluids. It can get rid of various gas of invasive drilling quickly. Vacuum degasser is very important for returning mud gravity, stabilizing mud viscosity and reducing drilling cost.

Features & Benefits

Skid-Mounted – Simplifies spotting and installation.
Self-Contained – The unit consists of a cylindrical vacuum tank with internal baffle system, vacuum pump, jet nozzle and three-way float valve.
Three-Way Float Valve – Unique design allows venting to the flare line during hydrogen sulfide service.
High Performance – The D-GASSER can handle up to 1,000 gpm while restoring mud to its original density.
Robust – The unit is ruggedly built and is coated inside and out with a corrosion-resistant epoxy to ensure long life and minimum maintenance.

The majority manufacturer in China are focus on oil drilling mud system is DC professional drilling solid control manufacturer,  it has a very important role for oilfield , mud mixing system and other industry. Any interest please contact us for inquiry.

Vacuum degasser is the second stage solid control equipment, which is used when drill above 3000m well, so it is very important for drilling. And how to install it and what hidden dangers it has, please continue to look down.

Common hidden dangers in installing a vacuum degasser;

(1). The degasser is not connected with a flare line pipe, or the pipe is not at least 15m from the mud tank area.

(2). The relief pipe of the degasser shrinks in diameter ot is bent, so that the gas is not delivered smoothly.

(3). The relief pipe of the degasser is upright, releasing gas above the mud tank area.

vacuum degasser

1. Hazard:
The degasser is not installed with a relief pipe, pr the pipe connected outside the tank is less than 15m away. The gas discharged will accumulate in the tank area, casuing danger of explosion.

Remedy:
The relief pipe of the degasser is connected 15m beyond the tank area. The flammable pernicious gases can be ignited at the wellhead if necessary, the 15m relief pipe is connected beyond 15m when the degasser is used.

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2. Harden:
If the relief pipe of the degasser has a reduced diameter or is bent, it decreases the efficiency of removing gases.

Remedy:
The inside diameter of the relief pipe of the degasser should not be less than the open diameter of the outlet, and should open toward the road ahead. If the hose is used, it should not be deformed due to compression; a right angle bent should be used to turn a corner.

3. Hazard:
The relief pipe discharge directly above the tank area. Because the outlet of the pipe is about 3m above the surface of the tank, permicious gases cannot be ignited and set on fire. Inflammable pernicious gases will accumulate around the tank area.

Remedy:
The relief pipe of the degasser is connected 15m beyond the tank area. Inflammable pernicious gases can burn at the outlet when released.

Vacuum degasser is a high-efficiency in-line module that removes dissolved gases from HPlC Solvents. Its unique design assures reliable continuous operation and the highest level of continuous performance available without the need for helium degassing. Up to five solvent lines maybe degassed simultaneously by one unit. This type of equipment is part of the final polishing stage of a water treatment process to produce ultra high purity water.

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How to works of vacuum degasser

Vacuum degasser work by creating lower pressure inside a vessel so air or other gaseous impurities can be removed from a substance, such as water or even molten steel. The air is siphoned from the vessel after pressure is lowered enough to force the gas from the substance. A high-vacuum process environment is maintained for a variety of product testing and laboratory application.

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Features of vacuum degasser

1.Negative pressure degasser can efficiently separate gas and liquid, filter out impurities and ensure smooth exhaust;
2.During the working process of water ring vacuum pump, it always stays in isothermal condition, which is suitable for the suction of flammable and explosive gas and the performance is safe and reliable;
3.Drilling mud hit the wall through the window of a rotor at a high speed, bubbles in the mud broken thoroughly, the degassing efficiency is high and more than 95%.
4.The application of gas water separator will not make the water and gas discharged simultaneously and the discharge pipe is always clear.

Vacuum degasser are positioned downstream from mud/gas separators, gumbo removal equipments (if utilized), shale shakers and mud conditioners (if utilized), while hydrocyclone desander and Decanting centrifuges follow in the arrangement.

A vessel into which drilling mud is pumped to remove gas entrained in the drilling mud. Modern, compact degassers use three commonly recognized methods of degassification: centrifugal force, turbulence, and vacuum, See degassing drilling Mud.

Degassing drilling mud

An important part of well-drilling operations is keeping the drilling mud free of entrained gas, or bubbles that enter the mud as it circulates downhole throgh gaseous formations. One of the three functions of mud is to provide sufficient hydrostatic head to control a kick when high-pressure oil or gas is encountered.

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Vacuum Degasser Working theory:

When mud of a certain density is circulated, it can become infused with gas to an extent that, although the volume of mud may increase, the density is severely reduced. To guard against this dangerous situation, the mus is degassed at the surface. Several kinds of equipment get the gas out, but all have one aim in common: to make it possible for the gas bubbles to free themselves.

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One method flows the mud over wide sheets so the slurry is no more than one-eight to three-eights thick and the bubbles may come to the surface and escape. Another method sprays the mud against a baffle in a spray tank that squeezes out the gas. A third method directs the mud through a vacuum tank where, under reduced atmospheric pressure, the bubbles of gas expand and break out of the slurry.

You are welcome to contact us to get more detailed infos, we will supply cost-effective vacuum degasser and satisfactory pre-sale, sale and after-sale technical services.

Working principle of DC vacuum degasser

The vacuum degasser uses the suction of the vacuum pump to establish an under balanced pressure area in the vacuum cylinder and causes the drilling fluid into the hollow shaft of the rotator through suction pipe under the atmosphere pressure, and then lets the fluid spray to the walls of the cylinder from the windows on the hollow shaft, now the gas bubble cut in the mud may break and run off in the function of vacuum pump suction to a safe area due to the fluid collision and bubble separator.

vacuum degasser

However, the mud will enter the drainage cavity forced by its self-weight and pass the rotator and discharge off the cylinder. In addition, drilling mud can enter the pump cylinder only through the suction pipe, and can’t be sucked in through the discharge pipe because the vacuum pump and the master motor are started simultaneously and the rotator connected to the motor will revolve at a high speed.

Difference on vacuum degasser and poor boy degasser fluid processing

Vacuum degasser usually used to separate less gas than poor boy degasser. Although they both are degassing devices. Poor boy degasser is set up before shale shaker in the oil and gas well drilling. Before fluid flowing to shale shaker it need to be processed by poor boy degasser for safety working condition. Especially when the well depth is more than 4KM.

NOV(National Oilwell Varco)Nov Brandt Solids Control Division Is very famous brand around the world.

Vacuum degassers mechanically remove entrained gases such as hydrogen sulfide, carbon dioxide and natural gas from the mud system. Entrained gas can reduce the hydrostatic head of the mud column and can cause catastrophic well control problems.

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BRANDT™ manufactures negative pressure (vacuum) and atmospheric degassers. Vacuum degassers utilize negative pressure to withdraw entrained gases from the mud. In order for this to work, mud is pumped through a venturi, which develops a negative pressure, thus sucking mud into the unit. The mud then flows over dispersion plates, arranged either horizontally or vertically, creating thin sheets of gas-cut mud.

But now there are many Chinese manufactures can produce the vacuum degasser same like Brandt. DC Solids Control Is a China based Solids Control equipments manufacturer, we also offer worldwide vacuum degasser and services.

vacuum degasser

Our vacuum degasser is constructed by main vessel, gas water separator, vacuum pump, motor, and eletric control cabinet. The vacuum degasser could be used in many field, like commercial uses, agricultural uses and oilfield uses. Hereunder we talk about the oilfield uses.In oilfield drilling fluid system, there are 2 types degasser. One is poor boy degasser separate large quantity invaded gas, the other is the vacuum degasser, we also call it gas buster.

The vacuum degasser is a high-efficiency in-line modele that removes dissolved gasses from HPLC solvents. Its unique design assure reliable continuous operation and the highest level of continuous performance available without the need for helium degassing. Up to five solvent lines may be degassed simultaneously by one unit. The extremely low internal volume of each teflon AF channel offers very quick equilibration and very short startup times compared with PTFE degassing channels which have the same degassing efficiency.

vacuum degasser

A vacuum is pulled on a stream of water, and the vacuum draws the dissolved gas out of solution, removing it from water. There are two basic systems available – tower and membrane. In a vacuum degasser tower, water flows by gravity down through a tower filled with packing as a vacuum is drawn on the tower. The packing in the tower has a very high surface area, disperses the water very effectively, thereby enhancing the removal of O2, CO2 and N2. Performance is further enhanced by using atomizing nozzles as the water enters the tower. In a membrane degasser, water flows across one side of a membrane surface while a vacuum is drawn on the other side. Both types of systems use steam jet eductors or liquid ring pumps to generate the vacuum required.

VACUUM DEGASSING PROCESSES :

Vacuum degassing is practiced in the steel industry for several purposes. They are :

to remove hydrogen
to improve cleanliness by removing part of the oxygen
to produce steel of low carbon content ( < 0.03%)
to produce steels to close chemical composition ranges (including deoxidizers), and
to control pouring temperatures, especially for continuous casting operations.

Vacuum degassing is the process of removing dissolved gas from a liquid solution by lowering the pressure inside a vessel containing the solution. The reduced pressure inside the vessel causes the gas to become less soluble and separate from the liquefied material. After the vacuum degassing process is complete, the gas is removed from the vessel, and the pressure is returned to normal. This process is typically performed in a specially designed chamber known as a vacuum degasser. Vacuum degassing is often utilized in water treatment, laboratory testing, and soil purification procedures.

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Operational Theory:

Vacuum degasser utilize negative pressure by vacuum pump to withdraw entrained gases from the mud. In order for this to work, mud is pumped through a venturi, which develops a negative pressure in the vessel by vacuum pump, thus sucking mud into the unit. The choice between horizontally- or vertically-mounted units is typically based on the footprint requirements of the specific rig.

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Commercial uses
Vacuum degassers are used in some water treatment operations to significantly reduce the total gas pressure in water containment vessels. The vacuum is created by using either a blower or pump, and the degasser containment vessel is constructed from several materials, including steel, fiberglass and aluminum. Some containment vessels are built from concrete reinforced with metal fittings. Aqua vacuum degasser are often used to remove sulfur gases that can build up in water.

Function of vacuum degasser 

Vacuum degasser used in filling well, grinding well and sinkiang Di na well. All technology indexes all achieve the design requirements. Degassing effect is marked and will produce the good economic benefit. In the regular drilling process, if occur drilling fluid gas cutting, the vacuum degasser can dispose it. It can avoid the influence of gas cutting to drilling fluid working performance, decrease the abrading of mud pump, improve the efficiency of water and decrease the repairing times and stop drilling dispose times.

Comprehensiveness of vacuum degasser 

In unbalanced drilling, now have the degassing equipment – drilling fluid gas separator, it only separate the free gas in drilling fluid, but it can’t eliminate the not free gas. Drilling fluid often have gas cutting. The function of vacuum degasser is eliminating the not free gas. The equipment developed succeed provide the guarantee for the matched equipment of regular drilling and unbalanced drilling.

Why vacuum degasser can eliminate the gas 

In order to efficiency eliminate the gas in drilling fluid must meet the requirements:

The bubbles in drilling fluids should expose on the surface, will rapidly swell and fracture in the negative pressure condition. Gas cutting drilling fluid will remain a certain times in separation chamber. After gas cutting enter into separation chamber will present the turbulent condition flowing. So the degassing effect decided by the reasonable control of vacuum, the remaining times of gas cutting drilling fluid in degassing chamber and the turbulent condition in degassing chamber.

Degassing chamber vacuum is higher, the bubbles received the expansionary force in drilling fluid is bigger, the volume expansion is bigger, drilling fluid give the buoyancy is bigger, then bubbles are easy float to the drilling fluid surface to broken.