This presentation includes introduction, components, working principle, future scopes, advantages, disadvantages, conclusion and some graphs. It also gives information about NOx formation, environmental effect and control. The Exhaust Gas Recirculation (EGR) system is an emissions control technology used in internal combustion engines whose purpose is to reduce the amount of nitrogen oxide (NOx) emissions that are released into the atmosphere. Thank you!!

1. Topic :-
Exhaust Gas
Recirculation System
(EGR)
Submitted by :-
Suraj Kumar
Enroll. Number - _____________
Branch - Mechanical
Submitted to :-
_____________
________________
Collage name
LOGO

2. INTRODUCTION
 The Exhaust Gas Recirculation (EGR) system is an emissions control technology
used in internal combustion engines whose purpose is to reduce the amount of
nitrogen oxide (NOx) emissions that are released into the atmosphere.
 The EGR system works by recirculating a portion of the exhaust gases back into the
engine's combustion chamber, where they mix with fresh air and fuel to be burned
again.
 The recirculated exhaust gases contain fewer oxygen molecules than fresh air,
which leads to lower combustion temperatures and reduces the formation of NOx.

3. WHAT IS NOx (NITROGEN OXIDES)
 Nitrogen oxides (NOx) are a group of highly reactive gases that are formed when fuel is
burned at high temperatures, such as in internal combustion engines.
 They are composed of nitrogen
and oxygen atoms, and include
compounds such as nitric oxide
(NO) and nitrogen dioxide
(NO2).
 Major source are transports
(diesel engines)
 The peak temperature during
diesel combustion typically
occurs at around 2000-2200
degrees Fahrenheit (1100-1200
degrees Celsius)

4. ENVIRONMENTAL
IMPACTS OF NOx
 NOx emissions are a major contributor to air
pollution and can have negative impacts on
human health and the environment.
 When NOx reacts with other chemicals
in the atmosphere, it can form ground-
level ozone, which can cause respiratory
problems and other health issues.
 NOx can also contribute to the
formation of acid rain, which can
damage forests, lakes, and other
ecosystems.

5. REDUCTION OF NOx
 In order to reduce an engine should run at a lower temperature than the normal
temperature.
 Reducing cylinder temperature can be achieved in following three ways :-
1. Enriching the air fuel mixture.
2. Lowering the compression ratio and retarding ignition timing.
3. Reducing the amount of oxygen in the cylinder.
 Using new and advance technology like Exhaust Gas Recirculation (EGR),Selective
Catalytic Reduction (SCR), Exhaust Gas After-Treatment, etc.

6. BASIC COMPONENTS OF EGR
 The basic parts of an EGR :-
i. EGR valve: This valve controls the flow of exhaust gas from the exhaust system
to the intake manifold.
ii. EGR cooler: This component cools the recirculated exhaust gas before it
enters the engine's intake manifold. Cooling the gas reduces its volume and
oxygen content, which reduces combustion temperature and NOx formation.
iii. EGR piping: This is the piping system that connects the EGR valve to the
intake manifold and the exhaust system.
iv. EGR control system: This includes sensors and electronic control modules
(ECMs) that monitor and control the EGR system's operation. The ECM adjusts
the amount of recirculated exhaust gas based on engine load, speed,
temperature, and other factors.

9. EGR
valve
EGR
cooler
EGR piping
Exhaust Gas Recirculation

10. WORKING PRINCIPLE OF EGR
In exhaust gas recirculation, some of the exhaust gas is drawn off from the exhaust
system, cooled and redirected back into the cylinders . Although the exhaust fills the
combustion chamber,
it is not involved in the combustion
reaction that takes place in the cylinder
due to its low oxygen content. The
speed of the combustion process overall
is thus reduced, with the result that the
peak flame temperature in the
combustion chamber is lowered. This
dramatically reduces the production of
nitrogen oxides.

11. EGR OPERATING CONDITION
 There are three operating conditions for EGR flow.
1. No EGR flow
2. Low EGR flow
3. High EGR flow

12. VARIATION OF BSFC WITH ENGINE LOAD

13. EXHASUST GAS TEMPERTATURE V/S
ENGINE LOAD

14. BRAKE THERMAL EFFICIENCY V/S ENGINE
LOAD

15. FUTURE SCOPE
 Integration with other technologies: EGR is likely to be integrated with other
emission reduction technologies such as selective catalytic reduction (SCR) and
diesel particulate filters (DPF) to create more comprehensive emission control
systems.
 Increased use in gasoline engines: While EGR is commonly used in diesel engines,
it is also becoming more prevalent in gasoline engines as emissions regulations
become stricter.
 More advanced control systems: Advances in engine control systems are likely to
enable more precise control of EGR, allowing for more efficient operation and
greater emissions reductions.

16.  Greater use of electric and hybrid vehicles: As electric and hybrid vehicles become
more popular, the use of EGR may decline, as these vehicles do not rely on internal
combustion engines.
 Continued development of alternative fuels: The development of alternative fuels
such as biofuels, hydrogen, and synthetic fuels may also impact the future of EGR,
as these fuels may have different emissions profiles and may require different
emission control technologies.

17. ADVANTAGES
 Reduces NOX emission.
 Decreases the engine temperature.
 Reduced engine wear and tear.
 Improves fuel efficiency.
 Increase the engine life.

18. DISADVANTAGES
 Reduces engine power.
 Increases engine complexity.
 Increases carbon buildup.
 Higher maintenance costs.
 Potential for increased oil contamination.

19. CONCLUSION
 Using Exhaust Gas Recirculation Technique in engines, the emissions are vary much
controlled due to lesser amounts of NOx entering the atmosphere.
 Exhaust Gas Recirculation is a very simple method. It has proven to be very useful
and it is being modified further to attain better standards.
 This method is very reliable in terms of fuel consumption.
 EGR is the most effective method for reducing the Nitrous Oxide emissions from
the engine exhaust.

20. THANK YOU