March 2022 Vol. 77 No. 3
Features
Directional Drilling: Muddy Waters: 3 Ways Fluid Cleaning Systems Can Improve Job-Site Success
By Richard Levings, American Augers Project Manager & Ben Clark, Derrick Corp. Civil Global Manager
As demand for underground construction projects continues to increase, getting the most from your equipment is vital to job-site success. For HDD operators, drilling fluid plays a crucial role in efficient operations by removing solids out of the bore hole, lubricating downhole tooling, cooling electronics and stabilizing the bore to prevent fluid surfacing out of the hole.
To assist HDD crews with their drilling fluid, manufacturers are utilizing fluid cleaning systems. The goal is to remove as many solids from the drilling fluid as quickly and efficiently as possible. While these machines go by many names – drilling fluid cleaners, fluid cleaning systems, fluid recycling systems and mud cleaning systems – they provide many operational benefits. From minimizing inadvertent returns and maximizing downhole production to helping contractors reduce environmental impacts, fluid cleaning systems are the flux capacitor to the HDD job site.
Here are three ways a fluid cleaning system can boost HDD uptime.
Reduce inadvertent returns
One universal fact of drilling is that drilling fluid will always follow the path of least resistance. When drilling goes according to plan, the bore hole created by the operator will always be that path of least resistance. However, if there is a different path of least resistance, then inadvertent returns can happen.
In other words, when an inadvertent return happens, drilling fluid surfaces through a path that HDD contractors did not intentionally create. This can happen in a variety of ways. From solids settling in a bore hole to natural intrusions such as ground conditions, tree roots and pre-cut trenches, any encroachment to the bore path could increase the risk of an inadvertent return.
To reduce this risk, HDD operators have turned to fluid cleaning systems to help manage the fluid flow and ensure solids are brought out of the hole efficiently. This is done by slowing down the drilling speed and increasing fluid velocity, so solids can stay suspended in fluid and not risk falling or settling in the hole.
With the help of a fluid cleaning system, operators can monitor if solids begin to move too slowly, which can cause solids to fall and create a dam. If build-up in the hole occurs, the fluid will find another path to the surface and cause an inadvertent return. Ensuring operators have a fluid cleaning system will help maximize downhole production and improve job-site productivity.
Reduce environmental impacts
As environmental, social and governance (ESG) regulations grow, and the industry looks to the future, environmentally friendly drilling practices are on the rise. The modern driller needs to understand how to minimize environmental risks, while protecting and improving the bottom line.
HDD contractors know that some underground construction projects require thousands of gallons of drilling fluid to complete a bore successfully. Without a fluid cleaning system, contractors are constantly spending time and money disposing of used mud and mixing new clean drilling fluid. Some areas have tightened restrictions on dumping mud at the job site, which means contractors are required to contain and dispose of the used drilling fluids only at approved waste facilities. As a result, contractors are spending more time disposing their fluids and less time where it really matters – on the job site.
The costs associated with containing and disposing of used drilling fluid can be significant. They include the need to buy or rent containment equipment, transportation and disposal fees, and the cost of fuel. The hassle does not end with disposal costs. Since used drilling fluid is being removed from the job site, HDD contractors must prepare more fluid with additional water and additives, resulting in further expenses and downtime.
However, many of these costs can be reduced by incorporating a fluid cleaning system. Such a system helps operators remove solids out of the drilling fluid, cleaning the water and allowing it to be reused. As a result, HDD contractors can cut disposal costs and reduce the environmental impact because less waste is created. In addition, by reusing the fluid instead of disposing it, contractors can spend less time preparing a new drilling fluid for a cleaner, more cost-effective operation.
Promote HDD uptime
A chain is only as strong as its weakest link and HDD contractors are only as productive as the machines they rely on. In the context of a fluid cleaning system, there are a few aspects of the system that determine a machine’s dependability.
One of the most integral aspects, however, is the shaker screen. As the first line of defense, shaker screens remove solids on the first cut and can dispose of them before going into the fluid cleaning system. When working together, shaker screens and fluid cleaning systems can promote HDD uptime and boost job site efficiency.
In one example, a local Buenos Aires HDD company needed to replace 5,800 feet of pipe beneath a large body of water that was known for its abundant fisheries and public park areas. This meant stringent environmental precautions were mandatory.
To be successful, efficient management of the drilling fluid’s component was paramount to complete the crossing on-time and with minimal environmental impacts. The equipment included a 440,000-pound maxi rig and a fluid cleaning system outfitted with two shaker screens. One motion shaker made the first cut on the raw mud with underflow fluid reporting to a 2,000-gallon primary tank below. Mud returns with high solids content were pumped from the bore hole into a fluid cleaning system. With the correct pumping rate during construction and flow rate during reaming, the operation was on a path to success.
However, as the new drill path paralleled the existing live pipe, great precision was required to minimize the risk of an inadvertent return. The continuous flow of clean drilling fluids contributed to a 25-percent reduction in the anticipated overall job completion time. In addition, the combination of a fluid cleaning system with a shaker screen helped minimize haul-off costs and diminished all detrimental risks to the parks and lakes.
Winning combination
Drilling fluids are a necessity to the HDD job site, but fluid cleaning systems are imperative to job site success. With the increase in environmental regulations and worker demand, fluid cleaning systems are not only helping solve contractors’ top fluid management pain points, but also increasing overall job-site ROI. Adding a fluid cleaning system with a shaker screen can help contractors cut costs, minimize downtime caused by inadvertent return or haul-off trips, and help improve overall job-site productivity.
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