Before a barrel of crude oil can become a gallon of gas or diesel, it must be refined — broken down and purified under intense heat and pressure, then mixed with additives. Oil refineries contain a network of pipes where these crude and refined products flow.
Pipes must be cleaned periodically to keep them running efficiently, and that’s where the Pigg® comes into play. Not a real pig, but a mechanical one about the size of a tin can, with a strong appetite for petroleum coke, nonetheless.
The Pigg is a patented product, the brainchild of Orlande Sivacoe, owner of Decoking & Descaling Technology (DDT) Inc. In fact, Sivacoe and his company holds 28 patents connected to both their equipment and process — a service the company has been providing refineries and other industrial plants for 27 years.
The patented Pigg can be equipped with a variety of metal studs and is made of a flexible polymer foam to decoke varying sizes of pipe. Plus, it is bidirectional, making it possible to tackle the most fouled sections of the pipeline.
The Pigg removes scale and coke deposits from inside the pipes of fired heaters, boilers, and heat-recovery steam generators. These producers will often shut down portions of a facility to perform a variety of maintenance jobs, so real estate is limited. To adapt, DDT designed a Quad Pass pumping unit that can clean four to eight process sections at one time, decreasing both the footprint of the equipment and the time required to decoke and descale.
The Quad Pass pumping unit delivers high-pressure water that pushes the Pigg through the pipeline at 5 to 20 feet per second. As the Pigg moves through the pipeline, its appendages shave away at deposits, which are flushed away by the flow of water and captured in the closed-loop water system. DDT also offers Filter Press Units that continuously recycle the water used for cleaning.
The Quad Pass pumping unit consists of CMU Series centrifugal pumps powered by a John Deere PowerTech™ Plus 13.5L engine.
Roman Korpus, vice president of DDT, says they selected the John Deere engine because it delivers consistent torque through the power band. The equipment draws on the torque when higher water pressures are required to push the Pigg through coke-laden sections of pipe.
"We run approximately 2,000 hours a year on each engine," said Korpus, "and they've held up great for us."
We run approximately 2,000 hours a year on each engine and they’ve held up great for us.