Electrostatic precipitators to capture diesel pollution?

Click For Summary

Discussion Overview

The discussion revolves around the feasibility of using electrostatic precipitators (ESPs) to capture diesel pollution from automotive sources. Participants explore the physics behind such devices, potential challenges in implementation, and the broader implications for pollution control, particularly in developing countries.

Discussion Character

  • Exploratory
  • Technical explanation
  • Debate/contested
  • Experimental/applied

Main Points Raised

  • Some participants question whether the physics of ESPs allows for effective capture of diesel particulates, noting potential issues with size and gas flow restrictions.
  • Others argue that black smoke from diesel engines indicates incomplete combustion, suggesting that improving engine maintenance could reduce the need for additional filtration systems.
  • A participant highlights the advancements in diesel engine technology, particularly common-rail injection systems, which have reduced particulate emissions significantly.
  • Concerns are raised about the effectiveness of ESPs in dealing with carbon particles, which may short circuit the device, and the potential need for additional filtration methods like HEPA filters.
  • One participant proposes miniaturizing ESPs for retrofitting on older vehicles that are not regularly maintained, emphasizing the importance of addressing particulate matter pollution in developing countries.
  • Questions are posed regarding the operational challenges of ESPs, such as cleaning mechanisms, carbon disposal, and the potential for increased complexity and cost in vehicle design.
  • There is mention of existing particulate filters and NOx after-treatment systems in modern diesel vehicles, indicating a shift in technology but also raising questions about maintenance and effectiveness.

Areas of Agreement / Disagreement

Participants express a mix of agreement and disagreement regarding the necessity and feasibility of ESPs for diesel pollution control. While some acknowledge the potential benefits of improved technology and maintenance, others remain skeptical about the practicality and effectiveness of implementing such systems.

Contextual Notes

Participants discuss various assumptions about engine performance, maintenance practices, and the technical challenges of integrating ESPs into existing vehicle designs. The conversation reflects a range of perspectives on the complexities of pollution control in automotive applications.

Who May Find This Useful

This discussion may be of interest to engineers, environmental scientists, automotive industry professionals, and policymakers focused on pollution control technologies and their implementation in vehicles.

zwanderer
Messages
3
Reaction score
0
I would like to understand if someone has tried/or atleast if its feasible to make a Electrostatic precipitators that captures automotive pollution from sources like this?

Does the physics allow to do that?

diesel-exhaust_gallery.jpg
 
Last edited:
Engineering news on Phys.org
:welcome:

ESP? What's that? Google says extrasensory perception. I doubt that is what you mean.

Edit: I see in the title that you mean electrostaic precipitator. Sorry.
 
anorlunda said:
:welcome:

ESP? What's that? Google says extrasensory perception. I doubt that is what you mean.

Edit: I see in the title that you mean electrostaic precipitator. Sorry.

Alright edited! :)
 
zwanderer said:
Does the physics allow to do that?
The Physics is OK, I think. The problem would be the massive volume that the device would take up in a motor car, in order to deal with the vast amount of particulates without restricting the rate of flow of the gases.
 
It should not be necessary to use an exhaust filter. Black particles are produced only when incomplete combustion occurs.
There are several causes of incomplete combustion.
1. Cold engine or faulty glow plug. Fuel condenses on cold wall then burns slowly.
2. Blocked air filter. Insufficient air to burn all the fuel injected.
3. Faulty injector. Dribbles rather than atomises the fuel.
4. Blocked fuel filter or low fuel. Injection pump spits rather than atomises the fuel.
5. Insufficient compression of air in cylinder. Failure of cylinder seals or turbo charger.
6. Too rich fuel. Maximum fuel setting on the injection pump is too high for the fuel being used.

Black smoke is an indication of a failure. Fix that fault and you will not need a particle filter.
 
  • Like
Likes   Reactions: sophiecentaur
Baluncore said:
It should not be necessary to use an exhaust filter.
But there is always the problem of particulates (despite what VW try to tell us) and they could be extracted with enough effort (and wasted engine power, I guess).
 
Older diesel engines with jerk pump injection are progressively being replaced by more efficient and cleaner diesel engines. It is hard to realize how significantly things have improved unless you drive an old diesel tractor or see an old diesel truck blowing black smoke.

The problem with particulates has been rapidly reduced as common-rail injection systems have been improved. Common rail systems permit accurate computer control of injection timing and fuel volume. https://en.wikipedia.org/wiki/Common_rail

An electrostatic precipitator would have problems with carbon particles as they would tend to short circuit the high voltage. If a filter was now needed it might be better to use a HEPA filter once the engine reached operating temperature.
 
Baluncore said:
Black smoke is an indication of a failure.

or a gearhead has "performance tuned" his electronic engine control unit
 
I agree to the above points that the technology is improving in a way that emissions can be fixed via repairs, upgrades. However, Particulate matter is the biggest cause of pollution in developing/thirdworld countries where 70% world population lives. The problem is- people don't maintain their cars.

My question technically is about miniaturizing ESP in a way that it can be retrofit behind vehicles who don't take their vehicles for repairs. Whether you maintain your engines- atleast you'll not pollute the environment.

Since HEPA is purely mechanical, it would have back-pressure on the engines. Right?

I am planning on running two experiments next week, and happy to report updates.
 
  • #10
zwanderer said:
Since HEPA is purely mechanical, it would have back-pressure on the engines. Right?
As does a turbocharger.
A centrifugal vortex separator might make a better filter. Could you integrate the separator into the turbine of the charger.

An inventor needs a cause. “Particulate matter is the biggest cause of pollution … ”. But that does not justify making things more complex and more expensive. Expensive new vehicles prevent the replacement of older polluting vehicles. So you may be better reducing the complexity and cost of new vehicles, to better reduce particulate pollution. Are you considering a compulsory retro-fit of ESP to older vehicles or only on new vehicles ?

Any filter system added to an existing diesel will have problems during a cold start. How will the ESP system be cleaned. Will it have a recirculating mechanism. How will the carbon be removed from the ESP? Might safe disposal be as an oil or water paste? Could that be recycled somehow? It cannot go through the fuel injection system because of the carbon particles.

Catalytic converters work for high temperature exhaust but not well for diesel. They are ignored when they fail and are sometimes removed. What makes you think an ESP would be treated differently and maintained by vehicle owners?
 
  • #11
Any update on your experiments??
 
  • #12
Aziz said:
Any update on your experiments??
Modern Diesel cars (in Europe at least) are fitted with particulate filters and NOx after-treatment.
 

Similar threads

  • · Replies 3 ·
Replies
3
Views
1K
  • · Replies 1 ·
Replies
1
Views
3K
  • · Replies 13 ·
Replies
13
Views
2K
  • · Replies 117 ·
4
Replies
117
Views
11K
Replies
7
Views
2K
  • · Replies 16 ·
Replies
16
Views
2K
  • · Replies 5 ·
Replies
5
Views
10K
  • · Replies 2 ·
Replies
2
Views
1K
Replies
1
Views
2K
Replies
22
Views
2K