The “greening” of diesel in North America has been an evolving process. Today, collectively, the diesel standards for fuel and engine technologies for on and off-road vehicles and marine vessels reduce diesel’s harmful emissions by more than 90 percent. In addition to increasingly stringent regulations requiring ultra-low sulfur diesel (ULSD) in everything from highway vehicles to locomotive and marine applications, engine manufacturers needed to adopt technologies to reduce NOx and SOx emissions in compliance with the Environmental Protection Agency.
In 2004, EPA standards required new engines and equipment to reduce emissions of particulate matter and smog-forming compounds to near-zero levels by 2014, beginning with a process called exhaust gas recirculation (EGR). EGR technology captures and returns exhaust to an additional turbocharger allowing the vehicle to re-burn approximately eight-to-12 percent of the exhaust. The result is lower SOx and NOx output, but a necessary retard to the engine timing had a negative impact on fuel economy and engine power.
Following on the EGR process, engine manufacturers then added a Diesel Particulate Filter to the exhaust stream. The filter collected the offending emissions before they exited the tailpipe, eventually regenerating the filter through high temperatures. However, this technology resulted in reduced fuel economy and a frustrating user experience.
The EPA Clean Air Act went into effect January 1, 2010, prompting engine manufactures to introduce the Selective Catalyst Reduction (SCR) system into engines to meet the new legal requirements. An SCR system can only operate properly with Diesel Exhaust Fluid (DEF) refined to achieve an exacting performance standard as defined by the International Organization for Standardization (ISO) and certified by the American Petroleum Institute (API).
DEF is a safe, synthetically derived urea solution added to a separate tank on the vehicle. The fluid is injected between the catalytic filter and tailpipe, spraying DEF into the exhaust system. Diesel Exhaust Fluid is consumed at approximately 4-to-6 percent of the diesel consumption of the vehicle. The effect is to neutralize any remaining NOx and SOx emissions to the point that manufacturers were finally able to un-retard the engines and achieve the emissions reductions without a performance loss – restoring fuel economy, engine power and eliminating user experience issues.
So, what, exactly is DEF made of?
Diesel exhaust fluid is a 32.5 percent solution of very pure, synthetically manufactured automotive grade urea in pharmaceutical grade deionized water. Urea is commonly used in the agricultural industry as a fertilizer, widely known as UAN32. However, the urea utilized to produce DEF must be of a high standard to eliminate any contamination risk or damage to the vehicle’s onboard SCR system. Diesel exhaust fluid is a stable, safe liquid, which is transparent and non-toxic. For every 100 gallons of diesel a vehicle burns, only four-to-six gallons of DEF is required to power the vehicle’s onboard SCR system. DEF must meet ISO Standard 22241 (ISO-22241-1, ISO-22241-2, ISO-22241-3) and API certification to be produced, stored and distributed by a top-tier DEF supplier.
Carson is the Northwest’s largest provider of high-quality API certified DEF.
Responsible environmental stewardship is vital to Carson. We understand that the standards for energy emissions are ever-evolving. Our goal is to embrace and champion these standards that move the industry and society forward. In the same way we pioneered the large-scale commercialization of Biodiesel and LCFS-compliant renewable diesel in Oregon, and we positioned ourselves as the leading provider of Diesel Exhaust Fluid (DEF).
After careful analysis of the available supply, future demand and formulation requirements – we took steps to become not just a distributor but one of the Northwest’s first DEF manufacturers. We wanted to ensure the success of DEF by offering an ongoing supply of the product manufactured to strictest API manufacturing standards.
The API certification program authorizes diesel exhaust fluid producers that meet the specified requirement to use the API Diesel Exhaust Fluid Certification Mark. 
This mark confirms the diesel exhaust fluids meet the ISO 22241 and DIN70070 requirements which guarantee the best possible performance of SCR systems.
We started in Portland by sourcing our urea prill, which is automotive grade urea in pellet form, to use in our proprietary solution. We then built out a state-of-the-art, American Petroleum Institute certified facility to manufacture and distribute our DEF, under our new business line: NEXGEN Products.
Today, Carson is the largest provider of DEF in the Northwest. We’ve even grown to add another manufacturing plant in SeaTac capable of producing a million gallons of DEF per month. Through the SeaTac location, we’re now providing NEXGEN DEF to Seattle and western Canada.
Our latest step has been to bring our product to the pump by adding NEXGEN DEF dispensers to an increasing number of Cardlocks throughout Oregon, making it easier than ever to access the latest in diesel system innovations.
To find out more about using NEXGEN DEF for your fleets, Call Us or visit our DEF page.
EPA Clean Diesel Timeline:
2006 – 2014: The EPA phases in more stringent regulations to lower diesel sulfur to 15 ppm. (ULSD)
2010: All highway diesel fuel supplied to the US must be ULSD; All highway vehicles in the US must use ULSD
>2010: The EPA Clean Air Act went into effect mandating a reduction in NOx and SOx emissions, engine manufacturers develop SCR (used with a DEF additive) and Gas Recirculation technologies to meet the requirements
>2014: All nonroad, locomotive and marine (NRLM) diesel fuel supplied to the US must be ULSD; all NRLM engines and equipment must use ULSD
DEF Advantages:
- Reduced emissions = less environmental impact
- Better fuel efficiency = lower operational cost
- Less engine wear and tear = less maintenance cost
- Fewer regenerations = more productivity
- Optimized combustion = increased power
- Safe, clean and reliable