an interesting paper on diesel electric hybrid

[mobile_bob]

the technology is interesting, and in my opinion there are things to learn from it that are applicable to what we
are trying to do here.

http://www.dieselforum.org/news-center/pdfs/Diesel%20Hybrid%20Electric%20Whitepaper.pdf

bob g

[veggie]

The coming fossil fuel problem could be pushed back many years if a concerted worldwide effort to switch EVERYTHING to diesel hybrid were put in place. Alas....a dream that will never happen.
After evaluating many systems for vehicular transport, the diesel hybrid keeps coming out on top.
VW (and others) in Europe have small diesel hybrids that are getting over 90 mpg in the city.
These cars are available NOW but various market forces are preventing their widespread adoption.
IMO the diesel hybrid is the ultimate solution based on today's available and mass producable technology.
The infrastructure is already here, and diesel fuel is less expensive to refine that it's pristine sister...Gasoline.

veggie

[cognos]

I like diesel engines. They've come a long way.
I like diesel/electric hybrids - for many applications - even better.

There is a problem in increasing diesel production at the refinery level. You need to pull it out of either the really heavy stuff (the "bunkers"), or the gasoline blend streams to do it, and physically/chemically convert it into "diesel" - which is not all that hard to do - but would make the finished product - wait for it - as expensive per BTU as gasoline...  which brings us right back to the starting point.

I see a bright future for bio-diesel fuels - whether straight or modified plant matter oils.

So - a hybrid diesel that can run on SVO, WVO, true biodiesel, regualr pump diesel -  or some combination - and meet modern standards for emissions - would be an ideal to shoot for, yes?

[clytle374]

I though the process they use now (hydrocracking?) allowed them to convert almost all of it to what ever they wanted, and it wasn't energy intensive.

Not an expert, just that's what I thought.   

[cognos]

Straight fractionation is the least energy intensive process in the refinery. This is where you get "straight run" product - products pulled straight out of the crude by simple distillation. Fuel crude produces fuel, lube crude produces lubricants.

Every other process adds complexity, energy, and therefore costs... plus often expensive catalysts, maintenance-intensive processes that are hard on equipment, etc... not to mention, most modern processes for decades have been geared toward increasing the production of gasoline, and aren't tuned to make other products efficiently.

Hydroteating diesel is mainly done to remove the sulphur, and it's a high-temperature operation with a platinum catalyst, that is quite hard on equipment. Hence, the increased cost of ultra low sulphur diesel.

Now - there is another hydrotreating process - often called a "Unifiner" or "Platformer" that can, to a certain degree, be moved (operationally) toward higher production of heavier fuels like diesel. But it's main purpose in life is to produce gasoline from heavier stuff (crap)... and it's just like a diesel hydrotreater but waaaaay bigger, hotter, severe, etc...

There is a "Cat Cracker" - my favourite production unit - more properly called a Fluid Catalytic Cracking Unit. Look this one up some time, they are amazing units to operate. Their operation can be changed on the fly to produce whatever fuel you want more of, even if it's propane - from heavy, heavy oils (not just crap, but BSFH - Black S#!t From Hell, that's a technical term )- black and solid at room temperature. But again, not cheap to operate or maintain.

Given the costs and complexity of producing any fuel in a refinery, I am constantly amazed that the price is as low as it is for any fuel...

I hope I live to see the day of clean hybrid diesels powering cars of usable size and utility in Canada, filling up at stations that sell renewably-produced bio-diesel fuels. Oh, and at affordable prices.

Hey, I can dream, can't I?

[Apogee]

I would submit that if they decided to go back to primarily making fuel and not attempting to extract other products (plastics) at the same time, then the distillation process would be just fine.

Not only would the fuel have higher btu output, and therefore result in better performance, the manufacturing processes would be far, far simpler.

I could easily forgo plastic grocery backs and 99% of all of the other junk coming from the plastics industry.

Steve

[cognos]

Many of the plastic precursors  - C4s and lighter - come off in the light ends in the crude anyway. It is possible to stick the butane, propane, ethane, methanes, etc. back together to make gasoline - or anything else - but it's more valuable as a plastics monomers feedstock. If it were more profitable, they'd feed the naphthas to plastics - but they don't, gasoline is still more valuable than plastic.

Of course, you are right, there are plenty of other products that could be fuels that are fed to be "plastics" - whether they be films (bagstock) or heavies like polypropylene or polyethylene, low molecular weight or otherwise. It's just a matter of economics. If the demand for gasoline goes down, well, the stuff has to go somewhere... it occurs naturally in most crudes to some extent, as does diesel, asphalt, propane, etc... it is quite surprising to see a barrel of crude oil costed out. No matter what you make with it, if you sell it after processing, it pretty much adds up to the same number of dollars. What varies most is the cost of production. Higher production costs eat into profit. So, like all business, it's a balancing act.

I suppose it's most efficient to just burn crude oil straight out of the well, with minimal processing. And that's what some ships do in their boilers, once they're out in international waters... crude oil can be pretty dirty stuff.