RECLAIMINGDrilling fluid management is an important consideration for pipeline

contractors, Taylor Nunnikhoven, Vermeer Corporation, USA, explains.

CONTROL

W ith all that happens on directional drilling jobsites, a crew’s biggest concern should not be what they are going to do with the mud afterwards. However, many new environmental regulations being introduced at state and local levels are causing contractors

to rethink what they are going do with leftover mud/drilling fluid, creating a logistical challenge and adding expenses that may not have been factored into the budget.

It is time to get fluid management back under control. To ensure that the disposal of mud does not become a major concern, contractors first need to understand the costs involved with drilling fluid management, plan for it when estimating a job, and have the right equipment so that crews can continue to work efficiently.

Costs of drilling fluid managementProper drilling fluid management (also referred to as mud management) is a necessity, and understanding the process and the costs associated is critical to help maximise a contractor’s bottom line.

“Drilling fluid management affects everything from the opening bid to the final cost of a pipeline project. It is highly regulated and involves several considerations. And, while it can be a source of annoyance for contractors, it is a constant presence on a jobsite and an essential element to horizontal directional drilling (HDD) in the pipeline industry,” says John Cope, Applications Engineer at Vermeer Corporation (Vermeer).

The process of drilling fluid management involves significant costs, many of which are not completely obvious. Even things that may initially seem to be free are not actually free.

For example, according to Cope, there are costs involved even if the contractor uses water that is pumped from a creek, river or pond. These costs accumulate from fuel to run the pump, manpower for plumbing, the transportation of the water, labour costs and truck expenses, to name a few.

The drilling fluids themselves are also a big expense, including picking up the fluid with a vacuum/pump and manpower to operate, as well as the equipment, maintenance and upkeep. A contractor may be able to dispose of the spoils from a job on a nearby farm or field, but in more urban areas, there are fewer dumpsite locations, which requires more travel. Actual costs of spoils disposal can vary greatly, but these expenses are often a huge drain on resources.

Drilling fluid management costs can really add up, which is why it is important to plan for it.

PlanningDrilling fluids are made up of more than just water, and each bore path has its own set of unique issues and expenses. No one jobsite will be the same as the next. Therefore, planning for potential issues will help the project remain productive and help contractors gain a competitive advantage.

“There are numerous contingency costs involved when it comes to mud management – some that can be seen and calculated, and some unseen costs that can only be captured at the conclusion of the bore,” says Cope. “The more questions that can be answered prior to the bidding process, the more likely a company will have a successful implementation of their drilling fluid management programme.”

The company’s customers have stated that it is important to distinguish between proactive and reactive considerations in a mud management programme. Proactive considerations can aid a contract when deciding if a specific job will be cost-effective or not. Similarly, reactive considerations must be contemplated before the bidding process. However, these considerations will truly come into play once the job begins.

Some proactive questions to consider prior to the bidding process include:

) Is the project buildable?

Figure 3. Reclaiming drilling fluids has become an economical option, due to the large amount of fluids required on jobsites and the environmental regulations about how drilling fluid should be disposed of.

Figure 2. Contractors need to understand the costs involved with drilling fluid management, plan for it and have the correct equipment to work efficiently.

Figure 1. It is important to be prepared for potential issues on a jobsite, as this will help keep the project productive and help contractors gain a competitive advantage.

World Pipelines / REPRINTED FROM APRIL 2017

) Has there been a constructability review?

) What is the availability and proximity to fresh water?

) What are the geological conditions?

) Has a mud engineer surveyed the project?

) Has the water been tested ahead of time?

) Can we get equipment and personnel in and out of the jobsite easily?

) Will access to the jobsite be an issue for services throughout the job?

) How far is the disposal site from the jobsite?

) What equipment is being utilised on the jobsite?

) Does the company’s responsibility for that fluid stop at the paid or not paid disposal site?

Reactive considerations that will be implemented during the job include:

) What is the climate?

) Did you experience inadvertent returns?

) Is the time it takes to do a turnaround longer than the reserve volume on hand?

) How much time is the crew waiting for the tanker or vacuum to return?

A contractor has a responsibility to consider these items so that they dispose of their drilling fluids in an economical way, while still adhering to local regulations.

“As an equipment manufacturer, we want to help our customers get their job done productively and cost-effectively,” says Patrick Robinson, Pipeline Commercialisation Manager at Vermeer. “Taking the proper steps to educate contractors and help them combat the ever-increasing environmental regulations in the HDD

Figure 4. Proper drilling fluid management is a necessity, and understanding the process and the costs associated is critical to help maximise a contractor’s bottom line.

Figure 5. Having a reclaiming system may be beneficial in the long run in areas with high dump fees, long distances to and from the dumpsite, highly regulated areas, or where water is scarce.

industry through innovative and engineered equipment is important.”

Reclaiming drilling fluidDemand for HDD projects is growing every year. However, whether a contractor is just starting out or has several years of experience, if they are not reclaiming fluids, they may be seriously impacting jobsite productivity and their ability to compete effectively.

Dumping costly water and drilling fluids additive mixture after only one use typically does not make sense. With the large volumes of fluids required on many jobsites and environmental regulations about how drilling fluid should be disposed of, reclaiming drilling fluids has become an economical option that all contractors should consider. One of the best ways to reclaim those fluids is through the effective use of advanced reclaiming technology available on the market today.

Cope states: “This technology is referred to as many different things – some call them recyclers, some call them shakers, some call them desanders, and we call it a reclaimer. A reclaimer is a piece of equipment that takes the drilling fluids used on a job, and cleans it to a point where it can be reused.”

The reclaiming process begins when fluid mixed with additives is drawn from the reclaimer’s clean fluid tank and runs from the high pressure mud pump to the drill. Drill cuttings and dirty fluid flow back to the entry pit and are pumped back to the reclaimer. This slurry flows across the reclaimer’s shaker decks, which separates the larger cuttings from the drilling fluid.

The remaining cuttings are separated from the dirty fluid with the desander cones that remove sand, and desilter cones that remove silt. Hydrocyclones separate

REPRINTED FROM APRIL 2017 / World Pipelines

particles from the fluid with a tornado-like motion, drawing solids to the side where they fall onto the shaker deck and are removed. Meanwhile, the recycled fluid is returned to the clean tank where it can then be reused in the drilling operation.

Determining if a reclaimer is a good fitWhile reclaimers can provide incredible value to a jobsite, they also present some significant capital consideration. Therefore, determining whether a reclaimer is a good fit on a particular jobsite depends on the various considerations outlined in the planning process.

In areas with high dump fees, long distances to and from the dumpsite, highly regulated areas or areas where water is scarce, having a reclaiming system may be beneficial in the long run. A reclaimer will help improve jobsite productivity and reduce the amount of fluid needed on a job by removing solids and recycling the fluid. All of this will help contractors have better control of their jobsites and not let the fluid control their decisions.

There are several features on reclaimers that can help make an operation more productive. It is important to consider which of these features is important to the success of a contractor’s operation. For instance, the latest Vermeer reclaimer technology features a recycling system built around a balanced elliptical shaker motion. Having

this motion helps convey lower gravity solids throughout the shaker bed, which can lead to less screen wear, increased cake dryness and reduce the ‘regrinding effect’ on solids.

Reclaimers come in a variety of sizes, and it is important to pair the right reclaimer with the right size rig based on the volume of mud required for a specific application. For instance, Vermeer offers a reclaimer product line engineered to support 100 000 lb (45 359.20 kg) drill classes and up. The newest model is the R250C reclaimer — a modular mud recycling system that can pair with a variety of directional drills, trailers, pit pumps and gensets on a jobsite. Its mobile design allows the machine to move where it is needed, when it is needed.

Robinson says: “With a Vermeer reclaimer, there is less need to haul truckload after truckload of water, less time spent co-ordinating disposal and delivery, as well as fewer trips to faraway disposal sites. Reducing your crew’s work can help lead to more productivity and more satisfied project owners.”

Drilling fluid management is a continually evolving process with numerous contingency costs involved. However, when it is properly planned for, invested in and supported with the right kind of technology, it can help improve the productivity and efficiency of a jobsite.

World Pipelines / REPRINTED FROM APRIL 2017