An after-treatment product or after-treatment system (ATS) is a device used to reduce harmful exhaust emissions from internal combustion engines. It’s a device that cleans exhaust gases to ensure that vehicles adhere to emission regulations.

These systems were implemented as part of the ongoing effort of auto manufacturers to reduce greenhouse gases in engines. Unfortunately, when it was first produced in the earlier part of the decade, ATS’s gained an undesirable reputation -- as a maintenance headache.

That said, technology has evolved, and it has improved the designs and delivery of new after-treatment products. As a result, they are a superior version of their earlier counterparts.

How do after-treatment products work?

ATS eliminates harmful emissions from getting into the air. Emissions form in the exhaust stream in a vehicle’s internal combustion engine. So, first, it moves from the exhaust side of the turbo into the after-treatment system. Next, it passes from the turbo via the DOC before entering the PDF.

Harmful gas particles are collected in the DOC and PDF; however, nitric oxide (NO) and nitrogen dioxide (NO2) remain in the exhaust. The NOx sensor, such as this one  http://www.dpfpartsdirect.com/collections/redline-nox-sensors makes part of the NOx reduction after-treatment system. It is usually installed upstream of the SCR catalyst and is responsible for measuring the engine-out NOx gas concentration. With this, you can check the optimum amount of urea injection.

To reduce the NOx levels, a light mist of urea such as Diesel Exhaust Fluid (DEF) is injected into the hot exhaust stream located in the Decomposition reactor. The exhaust moves from the reactor to the SCR system, converting the NOx and urea mixture into harmless nitrogen gas (N2) and water vapor. NOx sensors and the after-treatment products ensure that exhaust from vehicles achieves near-zero emissions.

Aftertreatment products have come a long way. Here’s how they’ve evolved:

• After a decade of reiterations, manufacturing engineers of today have more experience with the system.
• Technology such as the 3D, new body mixer technology, and the digital twin has enabled engineers to refine and redevelop the PDF, controls architecture, and the SCR.
• Using a combination of data analysis, science, material and chemical testing and engineering technology has increased conversion efficiency and reduced the possibility of failure modes.
• Post-production data analysis on after-treatment systems has enabled better tuning and controls, resulting in lower faults.
• The Aftertreatment products of today also reduce the need for regenerations, including parked regenerations.
• Newer ATS enables more time on the road with fewer emissions.
• These ATS’s are also self-cleaning, and some include an auto-elevate feature that removes hydrocarbon buildup by temporarily increasing exhaust temperatures while slowly increasing the RPMs
• ATS’s systems of today also come with telematics, resulting in fueled proactive and reactive improvements
• Engineers can also detect issues on after-treatment systems faster and easier.
• Engineers can identify symptoms of problems even before a machine malfunctions completely.
• Engineers can also proactively develop fixes and better engineer future systems.
• Through testing and R & D, after-treatment products will continue to evolve into more superior versions.