Cummins Power Generation has published a new white paper addressing the significant impact on the power generation industry by the progressively stringent emissions regulations from the U.S. Environmental Protection Agency (EPA). The paper, authored by Aniruddha Natekar, sales application engineer, Cummins Power Generation, provides useful guidance regarding milestones, terminology, technology and options for those who buy and operate generators.
The white paper describes the background of and the events leading up to the current state of the regulations, which is known as Tier 4 interim, or T4i. It also details the kinds of engines and generators that are subject to the new standard, which mandates sharp reductions in four pollutants: nitrogen oxides, particulate matter, hydrocarbons, and carbon monoxide. The paper then discusses the in-cylinder and aftertreatment technologies that Cummins is working with to meet the new standards.
The white paper considers the following in-cylinder technologies that are being used:
- Cooled Exhaust Gas Recirculation
- Variable Geometry Turbocharger
- Direct Flow Air Filter
- Ultra-Clean Exhaust
- High-Pressure Common Rail Fuel System
The white paper also examines a number of aftertreatment approaches:
- DOC, or a diesel oxidation catalyst, a flow-through device where exhaust gases are brought in contact with materials that oxidize unburned hydrocarbons and reduce emissions.
- DPF, or diesel particulate filter, a device designed to physically capture particulate matter from the exhaust stream.
- SCR, or selective catalytic reduction unit, which includes a “reducer” that is added to exhaust flow to create the reactions in a catalytic chamber.
The paper describes how each of the techniques works to reduce emissions, and it also weighs the challenges posed by these methods.
The white paper can be downloaded here.