high-pressure pump for another trip down the bore path
to extract cuttings and carry them to the surface.
Reclaimers changing HDD
The growing adoption of reclaimers is changing the HDD
industry.
“I’d say the increase in mud recycling is one of the
biggest recent developments in the industry,” Heinen says.
This evolution has been spurred by the rising costs
and number of regulations for drilling fluid management.
Requirements vary not just state to state or city to city,
but sometimes job to job because project owners have
different rules.
Also, Heinen says the number of dumpsites is
decreasing, and he’s aware of contractors who have
left jobs because the disposal process became too
burdensome. The issue has grown to the extent that it
should be a central consideration when bidding on a job.
Watland, of Dakota Utility Contractors, says thinking
through drilling fluid needs and disposal is a major part
of his job — and four managers who work under him also
spend time on this.
“It’s very, very hard today to figure out what you’re
going to do with your mud,” he says. “We have to figure
out where we’re going to go get water, how to dispose of
our mud and whether we should use reclaimers so that we
can clean our mud and reuse the drilling fluid so that we
don’t have so much expense.”
On a job in Arkansas in early 2016, a Dakota Utility
HDD crew was required to haul drilling fluid to a class I
landfill accepting hazardous waste. The nearest facility
was a two hour drive one way from the jobsite, four
hours roundtrip. That’s four hours in labour costs for the
drivers, transportation costs and a disposal fee of up to
US$1000 per load.
Frank Canon, one of the godfathers of drilling
fluid use in the HDD industry, also talks up the
importance of reclaimers. Canon, who retired last
year as a Senior Account Representative at Baroid
Industrial Drilling Products and remains active in
the industry as a consultant, says reclaimers can
help reduce the costs of drilling fluid disposal.
“The difference in cost between disposing of
solids filtered out by a reclaimer versus disposing
of the whole fluid can be tremendous,” he says.
The adoption of reclaimers is a trend that is
occurring worldwide, according to Canon. For
example, drilling fluid regulations are even more
stringent in Europe than in North America.
Picking a reclaimer
Although reclaimers are becoming more common
on HDD jobsites, when to use one is still most
often determined on a project by project basis.
Contractors should take into account the
Figure 4.
Among the features to consider when shopping for a reclaimer,
look for a machine with a pump and cleaning system designed to work at
the same flowrate, which helps to maximise productivity.
estimated cost of fluid disposal, hole diameter, bore
length, ground conditions and water source.
As a general rule, a project that requires 7500 gal.
(28 390.6 l) or more of fluid per day is one where a
reclaimer should be considered.
When it comes to picking a reclaimer, Heinen says a
contractor should work with a local dealer to find the
right fit. Some bits of advice from him include:
)
)
Make sure screens for the reclaimer are readily
available. Some manufacturers make custom-sized
screens only, forcing reclaimer owners to buy the
part from them.
)
)
Look for a reclaimer with a high-pressure pump
whose capacity is equal to the cleaner capacity,
which allows for higher efficiency.
)
)
Also important is having the pumps match the
cones, which helps improve the efficiency. Some
manufacturers undersize pumps to lower the
purchase price of a reclaimer, but that could cost the
owner over the long-term because the mud won’t be
as clean.
)
)
Get a unit that effectively removes sand. Sand that
gets through the reclaimer process can harm the
pumps on a horizontal directional drill.
)
)
A reclaimer’s mixing and cleaning capacities should
be robust enough to meet a contractor’s needs.
Some units fall short in those categories.
“Drilling fluid disposal, its cost and the location
of dumpsites, are a growing headache for HDD
contractors,” Heinen says. “Fluid recycling, through the
use of a reclaimer, has the potential to offer relief.”
MARCH 2016
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World Pipelines
83
