DPF regeneration alternatives
 

EDIT (Piwoslaw): Split from this thread.

Have you put any thought into developing a DPF that regenerates with power from a wall-socket?

(Who knows, maybe i could be as simple as a hole in the tube where a hot air gun fits.)

It takes an enormous amout of heat to get the reaction started--like a sustained 500+ deg F for several minutes. You basically have to ignite carbon. You're not gonna get that from a wall outlet.

What about replacing the DPF, as you replace a dirty air/fuel filter?
Remove clogged DPF, place in special machine which burns it out efficiently with gas or some other fuel. If this appliance wasn't too expensive, then the filter could be cleaned out every day or week, depending on driving style, etc.

I mean, in most circumstances using an ICE isn't the most efficient way of cleaning out a DPF.

During normal regenerations carbon is being removed from the DPF (as per it's design). Typically, when a DPF is "clogged", the solution is to either let the vehicle do it's normal regen or go out and run the engine hard to generate enough heat to clean it out. It that fails to "unclog" it, you can take the vehicle into the dealer who can run a program on the ECM to let it run extremely hot to try to clean everything out. If that fails, then the problem is not that the DPF is packed full of carbon, but rather ash. The ash doesn't burn off like the carbon, but rather just melts on in solid form. There's no way to remove it, hence the DPF needs replaced.

Every 400-500 miles when you're lucky - or every 100-130 miles when you're not ?
Hardly practical.

Car manufacturers don't even want their customers to know when the DPF is being regenerated. They'd rather leave them in the dark as to what's happening, and wether it's happening.

Which would need to be done centrally, as that machine is going to cost a bit, would be more or less brand-specific, and like the DPF itself generates the tiniest, most poisonous soot particles.

So you'd need to send the DPF somewhere, and you'd need another one - or a number of them - in the meantime depending on turnaround and your mileage.

It'd never work.

The most simple solution : don't buy new diesels.

You might be surprised what you can do with a couple of kilo-watts.

Dont buy a new diesel and plan on keeping and maintaining the rube goldberg machine based feel good emissions purification system unless you feel like losing a small fortune on a regular basis to keep it "clean".

All this clean diesel stuff is a not benifeting the consumer at all.
Inital cost is a lot higher, fuel consumption is higher, DPM is smaller and worse for you to breath, replacement costs for single pieces of this equipment is in the small used car range.

Want your regens to not burn any diesel fuel?
Buy a delete kit.

Dave's estimate of 500F is way too low. The exhaust temperature is not enough, the manufacturers dump raw diesel into the exhaust stream for additional heat, the clean out temperatures are going to be near cylinder combustion chambers give or take.

As to cleaning the DPFs, the HD truck ones are designed to be cleaned around 500,000 km or so.

I think that it would be possible to regen it without the use of diesel. I see two general ways to do this.

Alternative fuel
1. Inject Propane and have a spark plug light it to burn out the DFP.
2. Inject Ethanol and have a spark plug light it to burn out the DFP.
3. Inject Ethanol lightly as a detergent to break it up some and if needed occasionally have a spark plug light it to burn out the DFP. Not sure if that would work though.

Electric
If the temp that is needed is only 500F that would be easy as standard ovens reach 450F. With the use of insulation and induction plates from a stove heat could be directly applied to the DFP.

I was way off on the temperature requirement. It's over 500 deg Celsius. DPF manufaturer Johnson Mathhey quotes 600 C (1,100 F) here:
Johnson Matthey Catalysts - Emission Control Technologies - Active DPF Regeneration

But even if it was, 500 F, there's a big difference between slowly heating a confined oven up to 500 F and heating a stream of exhaust gas to 500 F.

Unfortunately, it's 750 euro to physically remove the DPF and erase the lines of programming in the ECU.

That's over 500 liters of diesel at our prices :eek:
Which is about 40% of what I use in a year.

There are no kits, and it's not legal either.
Chances are high the car will fail its yearly tech inspection as well, so I could only run it for one more year - if nothing else fails dramatically.

That's why my car uses an ureum fluid containing Cerium - it catalyzes the process so it happens at 350° C rather than 600° C.

In the states we can do that.
Other places where the government is allowed to micromanage peoples vehicles, not so much.

Actually it IS illegal here, too...it's just easy to get away with it in many places. Of course, it's technically illegal to modify your vehicle in any way that might negatively affect the emissions--even if it's something as simple as changing the igntition timing or modifying the intake.

Knowing a thing or two about DPF from an OEM perspective, I figured I would add to this...

Simply put: As was said, you won't be able to reach lightoff temp with electricity. Well, maybe on a 480v high amp industrial supply, but not too many people have one.

DPF regeneration dosing is a carefully calculated and metered injection of fuel over a period of time to allow slow, even heating and hence a small delta temp within the ceramic matrix. If you were to try to use another fuel and/or injection system for DPF regeneration, I would give you a 90% chance of cracking and ruining the DPF in short order.

Clearly the only answer is to gut the DPF.

The sort of issues I'm having with mine - frequent, continued regenerations taking 20 or more miles, up to a staggering 50 miles - apparently is also killing the ceramic matrix of the DPF :mad:

Shutting down during regeneration, also turns on the rad fan @ full blast for up to 10 minutes.
Opening the hood, the heat radiation is massive.

I have no idea what type of system your vehicle uses, however if regens are taking that long I would want to believe there is something wrong. Often times they use a delta pressure sensor to determine soot loading. If the pressure sensor has gone bad, it may be the cause of your frequent/extended regens.

I think I recall my regens taking 10-15 miles out on the interstate.

Just read this old thread (I am a relatively new member and trying to catch up on everything)

Would it not be beneficial to insulate the entire exhaust system with exhaust wrap? That would keep the temperatures higher which could mean that the dpf burns up the particulates stuck in it faster.

Just a thought...

Fresh ideas
 

Sounds like my 1500w heatgun is just under the required temperature.

Did an experiment mesured power consumption with a Kill A Watt gauge ,on a 1500 w heat gun/internal digital thermometer/ thermostat


maintain + - 5°f (2°c) 932°f (500°c)
max temp/ Max fan
warmup 1289w 11.08A
Maintain 932°f 1089w to 1289w cycletime ~ .5sec high ~ 1 sec. Low

Max temp/ Min fan
Warmup 1156w 10.98
Maintenance 771w to 1109w cycle time ~ .25 high ~ 1 - 2low

Fan only
57.8 watts .30A

add a few drops/min of diesel and you have a regen temperature without the engine running . Well under the max load for a standerd 110vac wall plug. Wether or not the CFM is within specifications to clear the ash without allowing it to become one with the ceramic. I dout it ... this could be run off a properly sized bank of suppercaps/supplemental Deep Cycle Battery to alow the regen to finish what it started.

If for home use,

This sounds like a perfect excuse to build an electric foundry. But with one door that has a heatproof hose compatible for the dpf.

The solution to my VW's DPF woes was to use DPF cleaner (bought cheaply in bulk from a tractor supply) and use it every tank.

One time it took 200km of highway miles to get the DPF light to go out. With DPF cleaner, problem solved, never had a light since.

The fuel saving seems to be about the same as the cost of the additive.

Renault are claiming the DPF in my new Trafic is good for life, and they claim the engine is good for 400,000km. I'm still using the additive.

good for 400.000, but lasts longer if treated well.

We have a lot of vans driven a half million kms here.