What is Solids Control Equipment, and How Does It Work?

Solid control equipment means the equipment or tools involved in removing the solid contaminants. These also include the gas entrapped in the drilling mud. The solid control helps reduce the material’s overall weight, making it easy to carry and easily portable. Several solid control equipment includes shale shakers, settling tanks, agitators, decanter centrifuges, vacuum degassers, mud cleaners, hydrocyclones, etc. It is a great way to reduce your carbon footprint and production of waste which comes with the transportation of drilling mud. The existing mud becomes clean and ready to use for the next project. Not only does it help save the environment by recycling it, but it also helps reduce the expenses of the project.

Understanding solid control types of equipment

There are several ways to remove the solid components from the mud. You can find different equipment and tools for the process. All such components that help remove solid waste are called solid control equipment. One of them is a shale shaker. It works by vibration control. The mud is made to travel over it, which helps collect the liquid part and the small solid components through the screen. This procedure eradicates up to 80% of solid particles from the drilled fluid. Now the part of the setting tank comes into play. It provides a space for large particles of the fluid to get collected at the bottom. Finally, the vacuum degasser has a different role to play. It helps in removing gas components from the mud. This is crucial for maintaining the density of the mud.

During the process of drilling, the gas gets trapped inside the mud. This gas alters the mud’s density, making it unsuitable for further use. However, the vacuum degasser helps eradicate the trapped gas molecules to make them suitable for use. Then, we also have another solid control equipment known as hydrocyclones. These are desanders or desilters. The main work of this equipment is to transmit the pressure produced by the centrifugal pump to centrifugal force. This helps change the suspended solids in the drilling mud out of the fluid. It is one of the most effective ways of removing the solid.

Then, the next name on the list is mud cleaner. It is an excellent blend of shale shaker along with a desilter. It comes with an exemplary screened chamber which is kept above another screen. The second screen constantly vibrates. There is another solid control equipment which is called a decanter. It helps in removing heavy solids. It can also be used for removing light components by incorporating centrifugal force. The container comes with a double screw type conveyor. It helps in rotating the direction while the container is in use. However, the speed of the rotation and direction change is executed in a slow range.

How does solid control equipment work?

Solid control equipment is a group of different tools which collectively provide the result of removing solids from the mud. The complete process has a set of four stages which are used for solid control equipment. These stages are designed to prioritize the tasks of removing the solid waste from the mud for the highest efficiency. The first step is to subject the mud to screen separation. The main aim of this process is to eradicate solid and fluid waste in the maximum amount. Equipment like shale shakers, mud cleaner screens, and scalper screens are used for this step.

Solid control equipments

The second step is setting separation. This step involved separating non-stirred or non-vibrating sections, unlike the first step. Examples of such tools are sand traps and settling pits. These are used for second-step clarification of the mud. The next step is to remove the removal of gas trapped inside the mud. This action is executed by degassers and settling pits. The last step is to execute forced settling on the mud. This is done by incorporating centrifugal force inside the mud container. The equipment used for this stage is hydrocyclones or centrifuges. The industry’s main categories or types of hydroclones famous are desanders, desilters, and micro-cones.

Different solid control equipment

As you already know, there are several types of solid control equipment. Every tool has its perks and advantages. Each tool plays a crucial role in the complete process of solid control equipment. Today, we will discuss different solid control equipment and their functioning. This will provide a broader perspective for thinking about different solid control tools.

Screen separation

This is the first device that is screen separation. As the name suggests, the device comes with a screen that helps differentiate the desired product from the undesired product. It is also one of the most commonly used solid control equipment. It contains a large screen under which another vibrating screen is placed. The mud goes upon the vibrating shaker. The drill cuttings come at the lower side of the shaker. As per the experts, the right combination of two techniques, scalper screens, and shale shakers, offer a piece of great solid control equipment. The cleaning or removing proportion comes around 80%. The shale shakers have further classification as well. One is an elliptical or circular motion shale shaker, and the other is a linear shale shaker. The other name for circular shale shaker is rumba shaper.

Settling separation

Solid control equipment can get very costly for a firm or organization. That’s why one of the cheapest ways of allowing drilling fluid can be allowing the drilling fluid to settle down. The process requires settling tanks or pits. Here, the drilling fluid can get settled without using any external force. The primary functioning of settling fluid is based upon overflow principles. The agitation requires to be zero to allow the settling of the solid waste. If the mud contains any significant solid components, they settle down. However, if a small particle comes into the picture, it will take a long time to settle. The main requirement is that the component’s size must be above the colloidal size. For siltz-sized particles, the complete setting separation can take several days. That’s why it is also an inefficient way of separation. The process requires the following prerequisites to happen. The first is that the solid needs to be heavy. Second, the mud should come with low viscosity. The third and last is that mechanical machines or tools can come into play to enhance the gravitational force.

Solid control equipment

Gas elimination

The gas gets trapped in the drilling mud. This changes the mud’s density, making it unfit for use. However, several primitive pieces of equipment help remove the gas in more straightforward ways. Such equipment is called a vacuum pump or float assembly. The vacuum pump provides a shallow internal pressure.

This pushes the gas into the degasser vessel. The gas collected in the vessel then goes to the thin layer formed inside the baffle plate. The low internal pressure, along with the thin liquid layer, promotes gas bubbles’ expansion. As the size of the gas bubbles increases,  the mud surface inside the vessel also increases. As a result, the separated gas comes to the upper part of the degasser. This is then collected and liberated by the vacuum pump. The gas from the vacuum pump sometimes is delivered directly into the air, or sometimes it is flared.

Forced settling

The hydrocyclones are responsible for doing forced settling. It is one of the last steps where the devices like desanders and desilters are used. These devices follow the concept of centrifugal force application. The mud goes inside the hydrocyclone at a tangent angle. The centrifugal force will force the solid components to go towards the walls of the hydrocyclones.

Hydrocyclones are divided into for parts;

Desanders

Mainly desanders come with a diameter of 6 m. The primary use of the desanders is taken in the top-hole parts. These are helpful in creating low mud weight. The desanders make the mud component or surface rise. The desanders are not meant for incorporating oil-based muds in the waste discharge.

Hydrocyclones

Desilters

The desilters come in a conical structure where a lot of cones are attached to the desilter. All these cones are less than 6 inches in diameter. The combination of desilters and desanders provides highly efficient results for mud separation. You can also add barites to make the mud of suitable weight. However, remember not to choose low gravity solids as well.

Mud cleaners

Next, we have mud-cleaners, a mix of fine-screened shale shakers, and a desilter. The types of equipment are kept over a very high-energy vibrating screen. This helps in distinguishing the mud’s solid components.

Conclusion

The solid control equipment helps manage the solid waste inside the drilling mud. Not only does it help in removing the complete solid waste, but it also prepares the mud for further use. It also targets trapped gas. There are several steps involved in a solid control equipment procedure. These solid pieces of equipment work upon different principles like vibration, calming effect, and natural settling.