Mud gas separators are the "kick-off" devices. We usually use the separators together with flare ignitors. Let's find more details below.

Mud gas separators specifications

There are main specifications including vessel size, thickness, design code, pipelines and fittings model, design pressure, material, and so on. Vessel size means the diameter and the height or length of the main vessel body. Flow rate and degassing capacity define the vessel size. For example, 800GPM or 1500GPM. The thickness is the gauge of the profile used to build the vessel. Such as 10mm, 12mm, and so on. Of course, the working pressure or design pressure determines the sheet thickness.

The design code affects material selection, too. Design code including ASME, GB standard, and so on. If we need to certify the separator under ASME and get the seal, there is a very definite requirement for materials. Pipelines and fittings including the inlet line, discharge line, vent line, drain port, valve and so on. Besides the pipe size, such as 5", 6", 8", 10" we also should pay attention to the length, pressure, as well as flange end specs.

Mud gas separators

For example, there is mud leg on the gas separator, it's also mud seal. That means the liquid level of discharge line after degassing. It helps to prevent separated gas flow back to the drilling fluids. Usually, the mud seal is no shorter than 3ft some clients request 5ft or longer according to the actual design of the degasser.

More information of the degassers

We know the degassers inlcuding vertical type and horizontal type. Usually, we use the vertical degasser. It occupies a less foot print. Furthermore, the horizontal degasser and vertical degasser are different with each other on some tinies. Such as vent line design, different ports arrangement, and so on.

The internal buffle blades helps to break the bubbles when drilling mud drop down from higher end of vessel. Then the gas will get released out of bubbles. Besides the internal buffle blades design, there is another pattern to let the gas out of bubbles. It's a hopper upside down, so when the fluid pass through the inlet port, the dimater of hopper suddenly becomes large and drop down swiftly, then the bubbles break and air flow away to the top and vent & ventilation.

Material grade is another issue users may concern. If the H2S content is high we'll consider the material resistant H2S and corrosion allowance. So, there is Q355, 16Mn, Q455 and so on material.

The external painting is an important factor of quality. We usually do the sand-blasting before the first layer epoxy zinc rich primer. The DFT is no less than 75 microns, then the epoxy MIO no less than 100 microns, and then Polyamide Cured high build epoxy 75 microns, finally the Aliphatic polyurethane 50 microns, finally the DFT is no less than 300 microns.

Poor boy degassers

Tiny details of liquid gas separator

Here we'll talk about more details of separator components or little parts. Such as the flanges, the relief valves and the pressure gauge, lifting lugs, supporting legs, and so on.

Flanges are used to connect pipelines between degasser itself and the extension line. Such as inlet line port, will connect the line from choke manifold, and the discharge line connects to the shale shaker feeder, while the vent line connects to the flare ignitor gas line. We need to pay attention to the flange pressure, and the standard. Such as 1.6Mpa, or 4.0Mpa, is it an ANSI standard or a metric flange. Is it a steel one or a stainless steel one? About the pressure gauge, do we need the normal pressure one or a high pressure one?

Regards to the legs, do we need the laydown supporting leg or not? For the supporting frame, do we need the regulated one or a fixed one?

Furthermroe, you can order the extension vent line up to 100m along with the poor boy, or you can fit that yourself. Pay attention to the flanges, should be same model or size with ours.

Ye, there are so many different configurations. Please come to us and get the optimal solutions to the degassers. Leave comments below or call us freely.

Mud gas separator is a kick off equipment used to process large quantity entrained gas. Among the gas, there is H2S, natural gas, SO2, methane, and so on. What issues impact mud gas separator degassing capacity?

Mud gas separator degassing capacity affecting issues

There are many issues may affect the degassing capacity. Such as degasser vessel size, the inlet and out put pipe size, the vent line size, the mud flow rate, degasser design or configuration, and so on. Furthermore, the gas ppm value and pressure will affect degassing efficiency, too

For example, APMGS1000 mud gas separator, the maximum degassing volume is about 6125m³/h. The mud flow rate is up to 300m³/h. So the permitted gas content in drilling fluid entering poor boy should be not higher than 20.4 under the normal pressure

mud gas separator degassing capacity

H2S elimination ability

The H2S elimination ability is the efficiency of the degasser. Usually we can't get a confirmed value. As the gas bubbles and the drilling condition at different site will be different.

The mud gas separator can get rid of entrained gas bubble sized over 3mm. The smaller ones will be hard to break and move out. However, we have vacuum degasser can handle about 95% gas out of drilling mud

So, if we wish get the H2S value is a certain value, we have to install the concentration meter and do the subsequent process

Mud gas separators types

The mud gas separator degassing capacity is impacted by degasser design or configuration. Such as the internal blades design, or if there is umbrella pattern nozzle instead of blades.

Mud leg or mud seal will affect final result, too. It will help to let gas flow upward till to the vent port and won't come back to the degassed mud.

There are degasser with 800mm diameter vessel, 1000mm, 1200mm. The pressure can be normal pressure, or high pressure. Such as 1.2Mpa, 6.4Mpa, 10Mpa, and so on. Different pressure requirements request different flange grade and the different thickness of material.

To resist high concentration H2S, we will use the Q345R material for more safe and durable operation. Please feel free to contact AIPU solids control if you have any other question

Poor boy degasser also referred to mud gas separator is an ideal equipment to operate when drilling is likely to encounter large volumes of gas. The separators are used primarily to separate and reliably vent large pockets of free gas from the active mud system. Usually it is set ahead of shaker but connected with the choke manifold.

Application of poor boy degasser

Poor boy degasser

The mud gas separator unit, with models engineered for use onshore and offshore, is used to reliably separate and reliably vent large pockets of free gas from the drilling fluid system. It is also ideal for use when an operator is drilling with an underbalanced mud column. The compact separator is well-suited for the space limitations of offshore drilling. It is skid-mounted and trailer transportable, which simplifies transport, spotting, and installation

It is different with vacuum degasser. As vacuum degasser request the pump to supply drilling mud for its operation. The drilling mud flow out through manifolds with certain pressure will push the fluid fall off from inlet and hit on baffles in separator. Then the gas bubbles will break and fly up via the vent line, as all drilling mud after processed will flow out of mud gas separator through discharge line with mud seal.

Aipu MGS Poor boy degasser

MGS poor boy degasser unit offers the industry’s high gas- and liquids-process capacity and enables operators to drill deeper large-diameter and exploratory wells at higher circulating rates. The unit improves kick handling capabilities, promotes optimal circulation rates, and facilitates drilling large-diameter holes through targeted zones. The MGS mud/gas separator unit increases gas- and liquids-handling capacities and enables the immediate sale of gas during drilling operations. It also provides more efficient separation of emulsions and gas-cut mud in either gas or oil environments, eliminating the need for a skimming system in a gas environment.

They separate and reliably vents pockets of free gas from drilling and workover operations. They ideal where drilling and workover are likely to encounter sour gas or when an operator needs to control the well with small, efficient equipment. Each unit is ruggedly built and coated with corrosion-resistant epoxy to ensure long life while processing hazardous and toxic gases

If clients prefer higher leveled products, we can also fabricate them with the Q345R plate. With more stronger resistance on H2S and so on. Please don't feel hesitated to contact us if you have any question or interest

Mud gas separator used in oilfield well control. Also refers to poor boy degasser, liquid-gas separator, gas buster, and etcetera.

Mud gas separator summary

Mud gas separator

Mud gas separator located at downstream of the choke manifold is one of the important well control equipment that you need to focus. It separates gas out of the mud after the gas comes out of hole. Gas will be vent to atmosphere via the vent line in derrick (offshore operation) or the line away from the rigs (land operation) and the mud will be returned back to the pit. While drilling, the mud gas separator should be lined up at all times and filled with the present mud weight currently used.

The poor boy is strictly used for well control only. There are some events that this equipment is utilized in a well testing operation. Additionally, inspection for the gas buster must be performed frequently the same as other well control equipment. People tend to forget about this since it is just only a vertical separator tank without high pressure specification like BOP, choke manifold, valves, etc. Erosion is one of the worst enemies to the vessel like this and it can be seen at the points where the drilling mud impinges on the internal wall vessel.

Oilfield mud gas separator detail

The concept of this equipment is density difference between liquid and gas. When the mud coming out from the choke manifold goes into the mud gas separator, mud will hit the baffle plates which are used to increase traveling time and allow gas to move out of the mud. Gas has lower density than air will move up and mud will goes down due to gravity. Mud leg will provide hydrostatic pressure in order to prevent mud going through the separator into the rig.

Each mud gas separator has limitation on much it can safely handle volume of gas. If the volume of gas exceeds the maximum limit, gas can blow through into the rig. It is very important that you must estimate gas flow rate on surface based on pit gain and kill rate in order to see how much expected gas on surface. This will be the limitation on how much you can circulate for well killing operation. You can estimate the volume gas on surface by using well control kill sheet provided by several companies. You need to ensure that the vent line should be as straight as possible with a larger ID in order to minimize back pressure while venting the gas out

For different drilling mud flow rate we request different sized diameter of mud gas separator. Such as 600mm, 800mm, 1000mm, 1200mm as usual models. However, special clients will request 900mm.

Tips to be noted on poor boy degasser

There are several considerations for mud gas separator design. You need to know the reservoir gas because if it is a sour gas (H2S), the mud gas separator should be able to handle this. The normal vessel will not work safely with H2S. Even though it has a name as “poor boy gasser”, it does not mean that it can be built in a cheaper way by some machine shops. The vessel must be fabricated to meet ASME specification and there must be a third party to certify it. What’s more, the scheduled preventive maintenance must be in place and strictly followed.

Furthermore, pressure gauge should be installed on the mud gas separator and frequently calibrated. This is very important because you will use this gauge to monitor the gas blow through situation. If the pressure in the vessel is more than hydrostatic pressure provided by mud leg, gas will blow through the vessel. By carefully monitoring, you will be able to react in a timely manner. If the pressure gauge shows you that pressure will be reach the limit, you should reduce current circulation rate to control volume of gas coming into it.

Another very important concept of blowing through while performing well control is the pressure value. For example, if the mud weight is 9.5ppg and the poor boy mud leg is 20ft, then the pressure to blow through is 9.88psi. The mud legs are same as shown on the figure. Different clients will request different height but we suggest at least it should be 4 ft.