Heating equipment has not evolved as quickly as other oilfield equipment in terms of efficiency, size, durability, emissions containment and safety.
by Dax Cornelius
August 19, 2015

Most recent advancements in hydraulic fracturing have been made in drilling and extraction technology rather than support services such as water heating. In a tough industry climate, frac service companies must provide greater value, options, safety, efficiencies and technology packaged around lower pricing, emissions and other environmental red flags.

During hydraulic fracturing, a single well consumes between 2 and 8 million gallons of water that needs to be heated. The heated fluid that is forced down the well at pressures up to 9,000 pounds per square inch (psi) is 94 to 96 percent water and a 4 to 6 percent mix of sand and chemicals. This liquid mixture is specifically designed to better propagate crude oil.

Engineers have discovered that hot water mixes better with the sand and chemicals, and it renders a smoother crude extraction process. When water at higher temperatures mixes with hot crude oil, coagulation is minimized compared with cold water extraction.

Water equipment accounts for an estimated 18 percent of gear on the frac operation and millions of dollars. Hot water used in fracking is growing in popularity in both the winter and summer months. Using hot water year-round keeps extraction temperatures consistent, which eliminates certain variables for the engineers who continue to refine the extraction process.

The growing demand for hot water during the past several decades has created about eight major water heater manufacturers and an estimated 15 major water heating companies that support the heating demands. However, frac water heating equipment has not evolved as quickly as other oilfield equipment in terms of efficiency, size, durability, emissions containment and safety.

Image 1. Frac water heating equipment (Images courtesy of Torrid Technologies Group)Image 1. Frac water heating equipment (Images courtesy of Torrid Technologies Group)

Temperature of the Waters

One thermal transfer technologies company specializes in manufacturing 99.9 percent efficient direct-contact frac water heaters. The focus is on optimal frac water heating, thermal transfer, efficiency, lower operating costs, lower carbon footprint and improved in operator comfort, safety and control.

Although the exploration and production (E&P) industry is recovering from arguably one of the worst recessions since the 1990s, efficient equipment has a lot to offer the industry. Most oil and gas companies are looking for more efficient, cheaper, faster, safer and smarter ways to frac.

Image 2. Ninety-nine percent efficient frac water heating unit when every BTU countsImage 2. Ninety-nine percent efficient frac water heating unit when every BTU counts
Image 3. Equipment filling water haulers in the BakkenImage 3. Equipment filling water haulers in the Bakken

Heating companies with less efficient, coil-type systems are searching for a way to lower their fuel and operating costs. Companies used to charge 0.03 cents per barrel per degree heated (not including standby time), but bids have fallen as low as 0.01 cents per barrel per degree. This kind of pricing is either putting heating companies out of business or causing them to pay just to stay in the game. Few coil-type heaters can make a profit with hot water pricing in its current state. Major oil companies are starting to ask for emissions reports and efficiency capabilities of the heaters used on their sites, making it even harder for heating companies to make a profit. These are all indications of an industry that is no longer accepting the way it has always been done and demanding a more efficient, safer and lower-carbon solution to heating frac water.

Image 4.  Most oil and gas companies are looking for more efficient, cheaper, faster, safer and smarter ways to frac.Image 4. Most oil and gas companies are looking for more efficient, cheaper, faster, safer and smarter ways to frac.

Full System Solutions

One company begins by manufacturing the trailer that will hold the following:

  • water piping
  • heat chamber
  • pumps
  • variable frequency drives (VFDs)
  • burner
  • generator
  • programmable logic controller (PLC) room

The trailers are designed to give the end user the option of using a gooseneck or pintle hitch on their heater that can easily be pulled by a heavy-duty category truck. The manufacturer can also retofit propane trucks with pintle hitches to pull the heaters or build a separate fuel tank trailer to provide several "make-sense" configurations and options for the user's preference.

The laws of thermal transfer, conduction, convection, resistance and diffusion leave no room for interpretation. It is math, and math does not lie. One frac water heater, at most any allowable flow rate or British thermal unit (BTU) power, will consistently demonstrate the exhaust gas stack temperatures to be within 10 degrees Fahrenheit of the inlet water temperature. So, if slickwater was pumped in from a frac storage tank at 35 F, the exhaust gas stack temperatures would be only 45 F or less.

Users can monitor and even operate the heater from a laptop, tablet or cellphone. This provides greater flexibility to the operator and greater safety and monitoring capabilities for any operation headquartered in another distant location. The heaters even provide the number of barrels heated and to what temperature delta for immediate billing. The operator can also control the heater from the comfort of an enclosed PLC room that has its own entry and exit with great window visibility.