Solidification Solution

Fly ash finds new use in treating oil cuttings and waste.
By Andy Glass | September 06, 2013

North Dakota has just reached the No. 2 spot in oil production in the United States and in order to do so, production and drilling must be extremely high. The nearly 200 drilling rigs in the state need special agents during and after the drilling process including drying agents to solidify the oil cuttings and waste.Fly ash is the leading drying and solidification agent in the Bakken oil fields.  It is widely used as it is affordable, capable of solidifying into cement, and has hygroscopic (ability to absorb water) properties.

Fly ash is primarily used in the concrete industry as a cement replacement and product enhancer. It makes concrete stronger, more durable and more resistance to chemical attack. It also is used in many other products and in many other products and processes, including in concrete block, as a soil stabilizer, and in carpet backing and roofing shingles.

Fly ash is generated at coal-fired power plants where dust collection systems collect the fly ash in the flue gas as it exits the plant. The use of fly ash throughout the world has incredible benefits to the environment. It keeps ash out of landfills while it improves and enhances products and displaces cement use.  Every ton of coal-combustion products used to improve our nation’s highways and buildings is a ton that is not deposited in a landfill, saving the same amount of space that the average American uses over 455 days. For every ton of cement that is replaced with fly ash, we would save enough electricity to power the average American home for 24 days and reduce carbon dioxide emissions equal to two months use of an automobile.

Fly ash’s role in North Dakota is increasing immensely. The two main uses for fly ash within the Bakken oil field are constructing the oil pad site and access road, and solidifying the drill cuttings and liquids that are a byproduct of the drilling process.

As a location is surveyed and is deemed viable for drilling, an earth-moving crew is hired to construct the pad site as well as an access road. With the truck traffic and weights of the loads, these roads and pad sites need to be well-constructed and able to withstand high use. These pad sites and roads are being topped with scoria rock over a base layer of solidified soil. Fly ash is being mixed with the earth and clay to produce an incredibly strong base that will allow the road to last. Fly ash is delivered via bagged material, pneumatic tankers or live-bottom grain trailers and applied to the ground. Water is applied to create the optimum moisture level. The soil material, fly ash and moisture are mixed to create a homogenous mixture. Once completed, it is rolled, compacted and then allowed to setup, creating strength.  Once the appropriate amount of time has passed, the top layer of scoria rock is applied.

The biggest use of fly ash is during the drilling process itself. Drill cuttings composed of drilling fluids (fresh water and oil-based liquid), dirt, clay and rock are created as the hole is drilled deeper and deeper. These materials are solidified two ways. One, as they come off the rig, they are mixed with fly ash and disposed of in the solids pit on the pad site. Or two, the solid and liquid cuttings are hauled off-site in closed top containers. Once the material reaches a landfill, it is solidified with fly ash.  Approved landfills are found throughout the oil field.    

With nearly 20 million tons of coal combustion products (CCP’s) under contract and contracts with over 90 utilities, 110 locations and 43 rail terminals, Headwaters Resources is the nation’s preeminent manager and marketer of CCP’s.  Headwaters Resources employs more than 700 people, serving utility clients and end-use customers across the United States and Canada.  Headwaters is the only CCP marketer owned by U.S. management and investors. Headwaters has long-term contracts with most utilities in North Dakota and eastern Montana.  Headwaters has just completed an ash-lime blending facility in Stanton, N.D., servicing both the bulk and bag market. Fargo, Washburn and Bismarck are the homes of the North Dakota offices. 

In addition to extensive marketing services, Headwaters has the resources, personnel, and technical expertise to provide total long-term management programs as well as specific CCP management services. 
Fly ash use is a great way to help our environment while adding value to the oil industry.

Author: Andy Glass
Business Development Representative