Slurry Pump Makes Light Work of Drilling Mud
BY BJM Pumps
According to the U.S. Energy Information Administration (EIA), oil and gas production in the United States in August 2014 was at its highest volume since 1986. Oilfield rigs are often located in remote areas. Although the rugged terrain may be barren, the site still has to be prepared to accommodate the rig and all of the required equipment, hundreds of feet of pipe, and one or more pits for drilling mud and other fluids. Before drilling can begin, the site must be cleared and leveled and in some cases access roads need to be built. A source of water is also required, which may mean drilling a water well, and one or more pits are dug and lined.
Fluids play an integral role in oil and gas exploration and production. When a new well is drilled, some form of fluid is needed. The base of this drilling fluid, or mud, can be freshwater or saltwater (brine) or it may be an oil- or synthetic-based liquid. The type of fluid and the additives used are determined in part based on the composition of the rock being drilled into. Cost and environmental impact are also considerations. The mud may also be modified as drilling progresses and the underground environment changes.
Ideally and increasingly, this fluid is recycled during drilling. To facilitate reuse, cuttings are allowed to settle out in a pit and the resulting liquid is pumped back to the wellbore.
Water is often a natural byproduct of the drilling and production process. Water may be trapped underground along with the oil and gas. Sometimes this produced water is incorporated and used in the drilling process.
This simple overview illustrates the fact that drilling a new well is a complicated process with many moving parts. A variety of providers are necessary at different times to deliver their unique services until a well is completed. Not surprisingly, moving all of this liquid requires pumps. United Rentals – Pump Solutions is a large equipment rental provider that helped West Texas Premix Pits (WTPP) of Midland, Texas, with those moving parts.
WTPP manufactures and sells premix pits, trash pumps and safety showers to oil and gas drillers in the Midland-Odessa area. Some of its clients needed to pump and recirculate spent drilling mud. Ian Walker, sales representative for United Rentals, recommended BJM Pumps’ KZN series heavy duty submersible pump.
Among other things, WTPP installs and maintains the reserve pits used during oil exploration. The pits are roughly 1-acre ponds that hold from 2 to 10 feet of drilling fluid that can be from brine or freshwater. The mud coming up out of the hole with the cuttings is deposited into one side of the pit and allowed to settle out, and the fluid that’s reused is pumped out of the other side of the pit. Although using a conventional pit configuration, WTPP is trying something new with its pumps. It’s floating the pumps on top of the liquid in the pit. WTPP builds specialized baskets to hold the pumps so they’re sitting in just 6 to 8 inches of water.
“It helps the drilling rig pick up cleaner fluid because the pumps are taking fluid off the top,” Danny Freeman, owner of WTPP said. “As the stuff settles out they have cleaner drilling fluid, and that results in faster drilling.”
WTPP initially rented BJM’s KZN series pumps from United Rental, but after the pumps proved their worth, Freeman decided to buy. “They were great pumps so we stuck with them,” Freeman said.
Although WTPP’s floating configuration has minimized the pumps’ exposure to solids, the oilfield environment still presents challenges, particularly if the water is brine. “Saltwater is hard on anything,” Freeman said. “I have customers flush the pump on a regular basis to keep it from getting corroded.”
As a result of the success they’ve had with the KZN pumps over the past two years, WTPP now operates 11 of the pumps in various oilfield installations across West Texas.
Mike Bjorkman is the vice president of BJM Corp., Old Saybrook, Conn. For more information, contact him at (860) 399-5937.
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No caption for image saved as KZN Pump, but place it “in” the sidebar—unless it sucks—if it ruins the layout with the big, beautiful one, then leave it out completely
Tough Pumps
Although not maintenance-free, KZN series pumps are rugged enough to provide long-term operation in harsh drilling environments, including those where the pumps have to handle a great percentage of solids, according to the manufacturer. Some of the characteristics that set the KZN series apart from other pumps include:
Wear Resistance: All wetted parts are constructed of abrasive-resistant 28 percent chrome iron (600 Brinell, 71 Rockwell C). In addition, a replaceable hardened wear plate is located on the suction side.
Solids Handling Capability: An integral agitator fluidizes settled solids into a slurry, making them easier to pump with less chance of clogging. The semi-open impeller handles abrasive solid concentrations as high as 70 percent by weight.
The KZN series pumps feature Class H motor insulation and built in amperage ( FLA ) and temperature overload protection; double silicon carbide mechanical seals in a separate oil filled seal chamber; a heavy duty lip seal to provide additional protection for the mechanical seals;
stainless steel shaft and shaft sleeve; pump volutes cast from hardened ductile iron (300 Brinell hardness), which is twice as abrasive-resistant as standard ductile iron with walls that are extra thick at the point where pumped slurry enters the discharge.