By New Standards, and Test Procedures, NOx Control has Become a Priority. Hybridization and Advanced Combustion Control are Key Trends Gaining Momentum
Exhaust emissions have always been an area of concern for the automotive industry. The problem lies in the fact that vehicles produce emissions when they burn the fuel to run the engine. Both petrol and diesel engines have a mixture of gases in their exhaust. Termed as “tail pipe emissions”, they are categorized as Criteria Air Contaminants (CAC) and Greenhouse Gases (GHG). CAC includes nitrogen oxide (NOx), sulphur oxides (SOx), Volatile Organic Matter (VOC), particulate matter (PM) and ammonia (NH3). GHG includes carbon dioxide (CO2) and methane (CH4) and nitrous oxide (N2 O), a colorless non-flammable gas which has upto 300 times the global warming potential of CO2.
NOx is formed when nitrogen and oxygen in air react at high temperatures. In general, the higher the peak flame temperature during combustion, the higher the NOx emissions. Diesel engines are considered to be more efficient than gasoline engines due to their high compression ratios. However, the downside of this performance benefit is that their peak flame temperature is higher than gasoline engines which results in higher NOx emissions as compared to gasoline engines. It is important to note that diesel was once promoted as an eco-friendly fuel by the EU, considering that diesel engines emit 60% less CO2 than a gasoline engine, recently the focus has shifted towards NOx emissions after the 2015 “Dieselgate” scandal that triggered a sense of urgency to bring tailpipe emissions to zero.
This research service titled “Technologies for NOx Emission Reduction and Control in Automobiles” discusses the current and upcoming regulatory standards and test procedures for NOx emissions from mobile sources and why vehicle manufacturers are scrambling to invest in emission control technologies in addition to pursuing ambitions in alternative drive train systems.
An overview of the different approaches adopted by automotive manufacturers to reduce engine-out emissions as well as exhaust after-treatment methods in light-duty and heavy-duty vehicles is provided with a detailed analysis of their technical drivers and challenges. The technologies are assessed based on their ability to meet standards, adoption potential, and their current state of maturity in the technology life cycle.
A listing of key stakeholders is presented along with recent innovations and patent filing trends to identify the growth opportunities for NOx emission monitoring and control technologies.
Table of Contents
1.2 Research Methodology
1.3 Tackling Real Driving NOx Emissions Is the Challenge
1.4 Fuel Efficiency Leads the Charge as NOx Reduction Catches up
2.2 Mobile Sources Contribute over Half of Anthropogenic Emissions
2.3 Classification of Mobile Sources for NOx Emissions
3.2 EURO 6 Pushed Automakers to Scramble for New Approaches
3.3 Importance of Real-time Monitoring and on-board Diagnostics
3.4 Sensors Play a Critical Role in the Evolution of NOx Control Strategies
3.5 Technical Barriers Dampen Progress in Advanced Combustion Technologies
3.6 The US and EU Drive Innovations in NOx Reduction Technologies
3.7 Outline of Advanced NOx Reduction Strategies for Mobile Sources
4.2 Hybrid EGR Approaches Being Explored to Improve NOx Reduction
4.3 TWC – Closed Loop System Effective for Gasoline Engines
4.4 SCR Continues to Dominate NOx Control for Diesel Vehicles
4.5 Diesel Oxidation Catalysts Targeted for PM and HC Reduction
4.6 DPF with SCR Catalysts Improve NOx Reduction
4.7 Engineered NOx Adsorption Systems for Oxygen-rich Exhaust
4.8 GPFs in GDI Powered Vehicles Passively Enhance NOx Control
5.2 Rapid Catalyst Heating Using Energy from Recuperation Engine
5.3 Electromechanically Actuated Internal Exhaust Gas Recirculation
5.4 Advanced CLD Fast Emission Analyser Improves Response Time
5.5 Cooled EGR System for Gasoline Engines Reduce NOx and Improve Fuel Economy
5.6 Novel Catalysts Using Spinel Technology for Natural Gas Powered Vehicles
5.7 Turbocharged Gasoline Alcohol Engine A Cheaper Alternative to Clean Diesel Engines
5.8 On-board Catalytic Reforming EGR Improves Fuel Efficiency
5.9 Advanced Sensor Enabled Engine Control in HCCI Engines
6.2 Engine Controls Experienced Exponential Growth in Patent Filings
6.3 SCR Dominates Patent Landscape as GPF Gains Momentum
7.2 Hybridization and Advanced Combustion Control are Key Trends