The war on NOx and diesel...

The war on NOx and diesel...

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DonkeyApple

54,921 posts

168 months

Tuesday 27th January 2015
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wack said:
DonkeyApple said:
Everyone also remembers catalytic converters arriving in the early 90s.

Everyone in London remembers the lobbying to prevent taxis and buses bellowing out plumes of smole
Anyone who spent any time in London in the 70s will remember the black snot , it used to be awful

I'm just wondering if it's as bad now but because it's a gas we don't see it

The figures for the car driven in London were very high
Yup. The key is that the old black snot was mostly soot from coal fires. We were burning black coal which generates a particulate that is quite large and very round. At the same time, our local coal is quite low in toxic elements, even sulphur.

What this meant was that the particulates, being smooth and having the lowest possible surface area didn't carry much in the way of toxins. There were fewer toxins in the first instance and also the particle size wasn't quite right to get deep into lung tissue.

At the same time that we were burning high calorific, low heavy metal black coal in our homes over in Eastern Europe they were burning a lignite called brown coal. It is low calorific and loaded with the sort of heavy metals and cyanides etc that you don't want to be inhaling. It burns at a lower temp so doesn't oxidise elements efficiently and the particulate form is broken and jagged with a large surface area for the toxins to adhere to. Basically, it is nasty and by the 70s we were researching the impact of these types of particulates and by the early 90s were were able to access ex Soviet data and begin to really see the impact on lung disease, mutations, cancers etc.

Diesel particulates have been known since this time to be unpleasant in the same way. More efficient burning has helped dramatically but somewhat offset by the massive growth in diesel output in the UK.

An interesting contributory factor to also consider in the South East is the decline in rainfall that has meant that it probably also takes longer for the particulates to be scrubbed out of the air naturally.

anonymous-user

53 months

Tuesday 27th January 2015
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kambites said:
Good! Diesels in city centres are hateful things.
Agreed and I'm glad something is being done about it!

DonkeyApple

54,921 posts

168 months

Tuesday 27th January 2015
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AC43 said:
kambites said:
Good! Diesels in city centres are hateful things.
Couldn't agree more. The stinky clattery things have no place in inner London. I get overtaken by loads of them as I cycle to work and the noise as they gun it past is truly unpleasant.
What is key is that diesel cars in London fall into three basic groups: Black cabs, minicabs, low end salesmen and the school run. So basically, racists, immigrants, s and fat s.

There is no mechanism for attacking these three groups combined. Richard Littlejohn would implode with confusion.

AC43

11,433 posts

207 months

Tuesday 27th January 2015
quotequote all
DonkeyApple said:
AC43 said:
kambites said:
Good! Diesels in city centres are hateful things.
Couldn't agree more. The stinky clattery things have no place in inner London. I get overtaken by loads of them as I cycle to work and the noise as they gun it past is truly unpleasant.
What is key is that diesel cars in London fall into three basic groups: Black cabs, minicabs, low end salesmen and the school run. So basically, racists, immigrants, s and fat s.

There is no mechanism for attacking these three groups combined. Richard Littlejohn would implode with confusion.
Funniest post of the day :-)



anonymous-user

53 months

Tuesday 27th January 2015
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There is also the fact that as a population we are living longer than ever before. Our "ageing" is going to cause us all significant issues in future as the old are not dying!

It's a trade off between convenience and risk, no absolutes. Lets face it, you can exceed some arbitrary NOx concentration limit (40ppm) and hence break a European law, but you are still quite free to smoke 20 fags a day! Of course when asked "are you worried about air pollution" the average VoxPop will say "oh, yes, very worried" and then jump into their car and drive off. In a world where more and more people are obese, and daily exercise is becoming the exception, NOx pollution is very low on the list of things to worry about!

The ONLY reason the politicians are suddenly getting their knickers in a twist is because some highly localised parts of the UK occasionally (in heavy traffic) fail to meet the EU "standards" and are in breech of EU legislation and hence we could be fined for non-compliance. And that is because some other faceless suit in Brussels has arbitrarily decided that 40ppm is the number below which we are all at risk. It's a bit like speeding, where 70mph = ok, 70.00000000001mph = Illegal, and yet the difference is RISK on either side of the arbitrary limit is immeasurable!


heebeegeetee

28,591 posts

247 months

Tuesday 27th January 2015
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Max_Torque said:
There is also the fact that as a population we are living longer than ever before. Our "ageing" is going to cause us all significant issues in future as the old are not dying!

It's a trade off between convenience and risk, no absolutes. Lets face it, you can exceed some arbitrary NOx concentration limit (40ppm) and hence break a European law, but you are still quite free to smoke 20 fags a day! Of course when asked "are you worried about air pollution" the average VoxPop will say "oh, yes, very worried" and then jump into their car and drive off. In a world where more and more people are obese, and daily exercise is becoming the exception, NOx pollution is very low on the list of things to worry about!

The ONLY reason the politicians are suddenly getting their knickers in a twist is because some highly localised parts of the UK occasionally (in heavy traffic) fail to meet the EU "standards" and are in breech of EU legislation and hence we could be fined for non-compliance. And that is because some other faceless suit in Brussels has arbitrarily decided that 40ppm is the number below which we are all at risk. It's a bit like speeding, where 70mph = ok, 70.00000000001mph = Illegal, and yet the difference is RISK on either side of the arbitrary limit is immeasurable!
Will you stop posting such common sense?! It's completely out of kilter with the entire website!

Baryonyx

17,990 posts

158 months

Tuesday 27th January 2015
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scherzkeks said:
As if petrols are so much better. Take a jaunt around any high-traffic area in NYC, Washington, DC, or any large American city, and you still need a gas mask.

The problem would seem to be automotive traffic in city centers.eek
Funny, I was in Washington DC and Manhattan in the summer last year. It was extremely hot and dry, and it was fine. Nowhere near as bad as UK cities choked with diesel smog.

spats

838 posts

154 months

Tuesday 27th January 2015
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Claudia Skies said:
USA has much tighter laws on diesel emissions than UK/Europe. Yet again, "those stupid Americans" are actually well ahead of us. It was the same with catalytic converters back in the day.

For instance, Mercedes diesels sold in USA have an additional system on the car to clean up their exhausts. Check out this link for details of the Blue-TEC system which injects a chemical (AdBlue) into the exhaust, breaking down nasty Nitrogen Oxide into harmless Nitrogen and Oxygen. Obviously the supply of AdBlue needs to be refilled from time to time.

http://www.mbusa.com/mercedes/benz/green/diesel_bl...
PSA has been adding similar chemicals into exhaust systems for years, probably since the early part of 2000-ish. Also Adblue is used in commercial vehicles from HGVs to vans like the Crafter. I know the VW Crafter would actually go into a forced limp mode until the adblue was refilled after a certain period of driving without it.


The Turbonator

2,792 posts

150 months

Tuesday 27th January 2015
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Jimboka said:
The Turbonator said:
I think Diesel engines are already being pushed beyond their limits in terms of economy and pollution.

You're constantly hearing about DPF failures, EGR valve failures, turbo failures, DMF failures, etc etc.

The reason I stuck with petrol was because of all the horror stories I hear on these forums. Diesels make a lot of sense for company car drivers, short term PCP deals and long distance driving. But for my own personal car, that I plan to keep for many years, then no thanks.
Do you always believe what you read on the Internet? Most diesel drivers like me have had no such issues. I prefer how diesels drive . I am not on first name terms with my local Esso attendant. So a very happy owner, like 99% are..
No, course not. But when you're reading new threads about it on a weekly basis, then I begin to see a trend.

Plenty of people who do high mileage and motorway miles, don't have issues. It's when the car is used for short trips around town that the DPF and EGR valve can clog up.

Plus, I've also spoken to plenty of taxi drivers, who have had to replace DPFs and EGR valves and were told it was because the car is only used for city driving, by whoever did the repair.

On that basis and because I mostly do short city trips to work, I decided to get my car with a petrol engine.

Yes, petrols can go wrong too but I've never seen a thread where someone is complaining about their petrol car having a clogged DPF or EGR valve.

spats

838 posts

154 months

Tuesday 27th January 2015
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well for sure no petrol would suffer from Diesel Particulate Filter failure wink

But I have had egrs fail, turbos fail, clutches go, carbon build up clogging intakes etc on petrols.

I can honestly say Ive had more issues with the last 2 petrol cars than my last 2 diesels.

They have also lasted longer, both now on 145-160k

JonnyVTEC

3,001 posts

174 months

Tuesday 27th January 2015
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spats said:
PSA has been adding similar chemicals into exhaust systems for years, probably since the early part of 2000-ish. Also Adblue is used in commercial vehicles from HGVs to vans like the Crafter. I know the VW Crafter would actually go into a forced limp mode until the adblue was refilled after a certain period of driving without it.
Have they? I thought PSA is a particulate filter type additive to keep that particular capture working properly. Adblue (urea) is required for Selective Catalyst Reduction (SCR) systems where its injected downstreem of the typical aftertreatment to reduce nitrous Oxides. Will be appearing on many cars to meet EU6 compliance for sale from Sept 2015.

Claudia Skies

1,098 posts

115 months

Tuesday 27th January 2015
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JonnyVTEC said:
Adblue (urea) is required for Selective Catalyst Reduction (SCR) systems where its injected downstreem of the typical aftertreatment to reduce nitrous Oxides. Will be appearing on many cars to meet EU6 compliance for sale from Sept 2015.
Yes. The oddest thing to me about the Dispatches TV programme was that it failed to mention this whole subject. More interested in spreading a scare story that second-hand diesel cars will become cheap or unsalable.

Mr2Mike

20,143 posts

254 months

Tuesday 27th January 2015
quotequote all
JonnyVTEC said:
Have they? I thought PSA is a particulate filter type additive to keep that particular capture working properly. Adblue (urea) is required for Selective Catalyst Reduction (SCR) systems where its injected downstreem of the typical aftertreatment to reduce nitrous Oxides. Will be appearing on many cars to meet EU6 compliance for sale from Sept 2015.
PSA is a French car manufacturer, i.e. Peugeot/Citroen. Adblue has been in use for many years in the UK, though more so for PSV and HGVs.

spats

838 posts

154 months

Tuesday 27th January 2015
quotequote all
JonnyVTEC said:
Have they? I thought PSA is a particulate filter type additive to keep that particular capture working properly. Adblue (urea) is required for Selective Catalyst Reduction (SCR) systems where its injected downstreem of the typical aftertreatment to reduce nitrous Oxides. Will be appearing on many cars to meet EU6 compliance for sale from Sept 2015.
I believe newer hdi engines now use Adblue instead of this older chemical. But yes they are different systems, I was simply saying the amercians aren't that far ahead of the Europeans on diesel tech. Both systems are there as an additional helper to clean the gases from Diesle engines. The FAP on the older PSA engines was to help lower the particulate combustion temps allowing the dpf to clean at lower temps. newer dpfs seem to be happy working at higher temps these days. I was shocked how high they go in forced regens after watching a VW van have one.

liner33

10,640 posts

201 months

Tuesday 27th January 2015
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charltjr said:
They've already addressed the NOx issue in the latest Euro 6 regs for diesel emissions. If anything I would expect to see tax breaks continue for the newer, lower emission cars rather than VED being increased because of the "NOx peril".

http://en.wikipedia.org/wiki/European_emission_sta...
Importantly though for diesels the emissions are not tested during dpf regeneration and levels of NOx rocket during this and regeneration becomes more and more frequent as the dpf fills up with ash, so hardly addressed in my opinion

JonnyVTEC

3,001 posts

174 months

Tuesday 27th January 2015
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Mr2Mike said:
PSA is a French car manufacturer, i.e. Peugeot/Citroen. Adblue has been in use for many years in the UK, though more so for PSV and HGVs.
Yes I knew that but a grammar fail on my behalf. I understand the Peugeot fluid is more to do with supplying the filter withe Cerium rather than NOx reduction. Peugeot also say that adblue will be added to HDi engine through 2014.

Otispunkmeyer

12,555 posts

154 months

Tuesday 27th January 2015
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clowesy said:
Interesting episode of Dispatches tonight which once again raised the issue of the effects of diesel particulates and NOx. A Labour party spokesman held his hands up and admitted that the introduction of the current VED system was a complete balls up as was telling everyone to buy diesel, both of which have contributed to significantly worse air quality in towns and cities. The issue of global warming or lack thereof depending on your viewpoint seems to be taking a back seat, being replaced by increasing concerns over the health effects caused by reduced air quality. And as most of you will know, Boris last year announced his plans to create an Ultra Low Emissions Zone in London whereby diesel cars in particular will face excess charges to drive in the city; the same idea has been proposed in other EU cities. With the diesel car and NOx emissions seemingly in the firing line, are we close to seeing a complete overhaul of the VED banding system the likes of which we saw under Labour? Are diesel cars soon to be taxed off the road just as many large engine petrol cars were?
They had a labour guy on that CH4 program the other night (great car con?). It didn't seem a terribly well researched program mind. Lots of hysterical nonsense. However, they had that guy on their holding his hands up saying it was probably the wrong decision. He did qualify it by saying it was the right decision at the time because they didn't have any of this other pollution information.

This IMO, is a double whammy. They first admit they are wrong, then they admit they were wrong because they didn't do any research. The petrol vs diesel emissions thing has been known since year dot. I have papers from the 80's that look at diesel emissions, petrol emissions. I even have papers where they test DPF's and are figuring out ways of regenerating them, like using microwaves or using cyclonic separators and electro-static precipitators to collect the larger particles. So his claim that, in 1993, they didn't know is complete arse-bks.

the TWC (three-way catalysts) exists because they wanted to reduce NO/NOx emssions (at the expense of CO2 emissions, because CO gets converted into CO2 as its immediately/locally less harmful than CO). So they knew these things aren't nice.

I don't personally see a way round this, except to have cars not powered by IC. Fancy injection systems aside (and fancy combustion techniques like HCCI, RCCI, and LTC which aren't ready for prime time and possibly never will be) most of the stuff on ICEs to bring emissions down is pure band aid stuff. Gubbins tacked on to solve the problem of the nasty things that result from combustion. You can get rid of some of them by improving combustion quality, but at the end of the day you're putting HC fuel in and therefore you must get some HC's like CO2 back out.

As emissions regs like EU7 drive emissions limits down, there'll only be more of this band aid stuff. Eventually you'll be buying a chemical factory that just so happens to have wheels and some seats.

sticks090460

1,074 posts

157 months

Tuesday 27th January 2015
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Jasandjules said:
Put harsh emissions testing on the buses..... Then watch the air quality improve.
This.

ChemicalChaos

10,360 posts

159 months

Tuesday 27th January 2015
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Claudia Skies said:
I think the answer is because it would hit,
  • Lorries
  • Buses
for which diesel engines still seem the best solution. Their emissions have been cleaned up enormously.

By the way, taking a lorry which is more then a couple of years old into London will land you with a clean air charge (like congestion charge, but a much bigger area covering the whole of London) of £200 a day!!
Sounds like a good excuse to start making all London deliveries with a fleet of 18 litre V8 petrol ANTARs biggrin

scherzkeks

4,460 posts

133 months

Tuesday 27th January 2015
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Baryonyx said:
Funny, I was in Washington DC and Manhattan in the summer last year. It was extremely hot and dry, and it was fine. Nowhere near as bad as UK cities choked with diesel smog.
I lived in DC for 25 years. On a typical July/August summer day in DC you can cut the smog with a butter knife, and as another poster mentioned, the fumes from rich-running V8s are rather hard to miss. It's no better, just different.