Biomass based diesel vs biodiesel - Page 7 - PeachParts Mercedes-Benz Forum

BillGrissom · #91 04-22-2015, 12:59 AM

Max power depends on what is the limiting factor for your engine. In our turbo-diesels, there is a limit on the air mass flow, via the turbo bypass which limits intake manifold pressure to ~10 psig. There is also a limit in max fuel flow thru the injection pump. But, if your car puts out some smoke at high power, you are already flowing as much fuel as might want. You can get even more power by pouring out thicker smoke, but people behind wouldn't appreciate. See youtube for M-B diesels spinning tires, w/ upgraded injection pumps, if you can see the car thru the smoke. Similarly, for tractor pull contests.

renaissanceman · #92 04-22-2015, 02:46 AM

What is the turbo bypass? The wastegate?

BillGrissom · #93 04-22-2015, 02:43 PM

Yes. It bypasses exhaust gas around the turbine. There is a rubber hose going from a port on the intake to a diaphragm that acts against a spring. When intake manifold pressure exceeds a setting, a rod moves to begin opening a flapper valve which lets exhaust bypass the turbine, thus limiting intake pressure. You can see the action better on many newer turbo-chargers (ebay or google images) since the rod is external. As the spring ages, the limit drops, so some people tweak the spring to regain max power. There is also a trick to booger with that "intake feedback hose signal" by forming a controlled leak, but do at your own risk since melted pistons will ruin your day.

My point on fuel BTU energy vs max power is that you are limited in practice by how much smoke you want to put out. If a lower BTU fuel atomizes better to burn more complete, it is possible you could get more power from that fuel at your "personal smoke limit", assuming the injection pump doesn't limit the fuel flow. I almost never "floor" my diesels since I see a little haze if the sun is behind me. But, it is one way to get tail-gaters to back off.

Cloudsurfer · #94 04-28-2015, 07:57 PM

Quote:

Originally Posted by renaissanceman

Which means theoretically you'll have 5% reduction in power on the power at the top end.

And, hypothetically, a 5% loss of economy.

renaissanceman · #95 04-28-2015, 08:51 PM

...unless you are getting more complete combustion! Most of us have not noticed a significant drop in fuel economy using HPR.

BillGrissom · #96 05-08-2015, 03:57 PM

One thing bothers me about Propel's Diesel HPR fuel. Most stations also sell their E85, and both have green price signs and use the same green fueling hose. I would never mix up, but I fear my son or wife filling up. Their thought process is "better use the cheaper one". I already dealt with my wife calling 6 yrs ago saying the engine sounded funny after she filled up my 1985 300D. I opened the cap, and it smelled like gas, and asked if she remembered to use the green pump. Wasn't sure. Must have been gas since I siphoned it and my minivan ran fine on it. I hate to imagine what horrors 85% ethanol might wrought. My son is slightly better. He once pointed to the air filter and asked "is that the engine?". Getting close.

renaissanceman · #97 05-08-2015, 04:45 PM

The Propel station in Fresno has E-85 dispensed through a yellow nozzle. Poor planning at yours, and asking for a lawsuit. What about the residual diesel or E-85 in the line from the last guy?

tjts1 · #98 05-08-2015, 10:17 PM

Are you sure? HPR is always green, e85 is always yellow.

BillGrissom · #99 05-12-2015, 03:32 PM

Actually, I'm not sure. I'll check next time. I was probably thinking of the last station I used where they had only a green nozzle, but they probably didn't have E85 there.

I expect that clueless motorists make mistakes often. I am sure many have put E85 in a gas car not designed for it, tempted by the low price. One co-worker mistakenly filled a rental gas car w/ diesel in Spain, confused by the nomenclature there. I have read various claims about what running gas in a diesel engine would do. I would most fear damage to the IP from lack of lubrication, but some say "too powerful" and such, though diesel has more specific energy per volume.

zibi1988 · #**100** 05-13-2015, 07:26 PM

https://www.youtube.com/watch?v=SppxyRIO3qo

well now we know which is cooler

tjts1 · #**101** 06-26-2015, 01:11 AM

Quote:

That car, it turns out, is part of another long-distance road trip that emphasizes a different green technology.

The car is being fielded by Neste Oil, which is attempting to drive it from Florida to California on a single tank of the company's NEXBTL renewable diesel fuel.

It set off from Atlantic Beach, Florida, Sunday with the goal of arriving in Santa Monica, California, on Friday--without refueling.

That car itself is a Superlite Coupe (SLC), with an aluminum monocoque chassis, fiberglass body, and a modified 1.9-liter Volkswagen TDI diesel engine.

Neste responded that its single tank holds "a little more than 48 gallons" to allow the car to traverse eight states and 2,400 miles.

The fuel is made from renewable materials, and its use can reduce carbon emissions up to 90 percent, Neste says.

U.S. Cross-Country Drive On Single Tank Of Renewable Diesel Fuel

Neste - Across

These guys must've hired the worst publicist in the world since theres zero media coverage.

BillGrissom · #**102** 07-02-2015, 02:46 PM

That car would draw crowds. They need to bring it to auto shows and fairs. I'm not sure what the tie-in to high mileage is, since I don't think they can claim the fuel gives more mpg, though diesels in general can. If they followed in the draft of that big truck, they could get amazing mileage.

A related angle is that bio jet fuel is getting much publicity, with a passenger flight soon from LA to SF, and companies setting up plants to make it from waste farm products. The main green tie-in is that it doesn't produce net CO2. The waste would decompose to CO2 anyway, so why not burn it instead of fossil fuel from below. Same argument for WVO and HPR.

tjts1 · #**103** 07-30-2015, 08:04 AM

Quote:

UPS Agrees to Buy 46 Million Gallons of Renewable Diesel

Now, one company is moving beyond the test phase. On Wednesday, UPS announced that it will buy as much as 46 million gallons of renewable diesel over the next three years, helping the company reach a goal of displacing 12 percent of the petroleum-based fuels in its ground fleet by 2017.

The renewable fuels, from three suppliers, are chemically so close to their petroleum-based counterparts that they can replace them in engines and pipelines. They are made from an array of bio-based sources, including palm and waste oils, and animal fats.

“It’s actually as good or even better from a performance perspective as traditional diesel,” including easy starts in cold weather, said Mike Whitlatch, vice president for global energy and procurement at UPS.

The market for renewable diesel is much smaller than for biofuel and ethanol — a little more than a billion gallons is produced each year, said Victor Oh, an analyst at Lux Research. But the market is growing faster, he said, and is expected to reach 1.6 billion gallons in the next three years, largely driven by demands for renewable jet fuel.

“It can drop in directly and can replace diesel completely without any kind of blend-wall, so that’s really one of its huge advantages, and one of the big interests in it,” Mr. Oh said.

On the ground, UPS plans to buy from Neste, a Finnish company that is the leading producer of renewable diesel; Renewable Energy Group, based in Ames, Iowa; and Solazyme, based in South San Francisco. Neste and REG produce renewable diesel from a variety of oils and fats, while Solazyme makes an algae-derived oil that is refined into renewable diesel. The market for renewable diesel is much smaller than for biofuel and ethanol — a little more than a billion gallons is produced each year, said Victor Oh, an analyst at Lux Research. But the market is growing faster, he said, and is expected to reach 1.6 billion gallons in the next three years, largely driven by demands for renewable jet fuel.

http://mobile.nytimes.com/2015/07/30/business/ups-agrees-to-buy-46-million-gallons-of-renewable-diesel.html?referrer=

otto huber · #**104** 07-30-2015, 11:05 AM

Quote:

Originally Posted by tjts1

http://mobile.nytimes.com/2015/07/30/business/ups-agrees-to-buy-46-million-gallons-of-renewable-diesel.html?referrer=

That's really good news. I wish that HPR had enough lubricity to run in my 617 engine, 30% is the highest blend with petroleum that I can run without the stuff leaking from my pump. I'm guessing that UPS did some thorough testing before committing to such a large purchase.

tjts1 · #**105** 07-30-2015, 11:31 AM

I don't think what's happening with your engine is a lubricity issue. The pump probably just needs new seals.