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Biodiesel From Sewage Sludge 88

Posted by timothy
from the french-fries-smell-better dept.
MTorrice writes "Scientists have developed a way to convert lipids from sewage sludge into biodiesel. The low cost and high yield of the sludge process may make it economically feasible as a source of biofuel, the researchers say. Today, biofuel producers use lipids in vegetable oils to derive biodiesel, a mixture of fatty-acid-like molecules. Biodiesel is compatible with existing diesel engines, burns with less pollution than petroleum-derived diesel does, and comes from renewable resources. But current biodiesel feedstocks are expensive, limiting the fuel's widespread use. The researchers from South Korea found that sewage sludge, the semisolid material left over from wastewater treatment, can yield 2,200 times more lipids than soybeans and costs 96% less to process. To turn the sludge lipids into biodiesel, the researchers heated them with methanol."
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Biodiesel From Sewage Sludge

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  • by Black Parrot (19622) on Friday August 31, 2012 @01:39AM (#41186867)

    Sewage: [slashdot.org] the new bitcoin?

  • by Chewbacon (797801) on Friday August 31, 2012 @01:42AM (#41186877)
    I've never taken my wife seriously when she's said my poo smells so bad I could use it to fuel my truck for the life of the vehicle.
  • lipids? (Score:2, Interesting)

    by Anonymous Coward

    free liposuction for biodiesel production. People could live on fat farms, where they are paid to be fat, in exchange for all of their 'lipids'. free doritos and fox news for all.

    read: soylent green won't be food, it'll be fuel.

  • Now we just need a car design that has a toilet you can hook your butt to directly so you can eat and poop while driving to keep fueling it.

    Cueing bad Matrix references in 3... 2... 1...

  • sure, it's certainly reusable and we're not going to stop producing it any time soon, but this isn't exactly going to help get us off of emission-producing combustion engines. I'd be interested to know the fuel efficiency and emissions of this fuel compared to fossil fuels. Anyone happen to be an expert on this? (my brief internet research isn't coming up with anything particularly helpful)
    • Re:Still.. biofuel (Score:5, Informative)

      by burning-toast (925667) on Friday August 31, 2012 @02:25AM (#41186989)

      Emission production as you state it is only a problem on a local level where the emissions are most concentrated (dense cities). Even electric cars will have emissions (either in production or at whatever plant is making the electricity for it). It's the part about digging up materials which have been locked underground for millions of years and then releasing those emissions into the atmosphere that is the global problem. If all of the energy and consumables your vehicle used during it's entire lifetime (including manufacture) were harvested from plants or otherwise scraped off of the surface of the biosphere instead of from within the ground you would essentially be close to net-neutral impact on the planet as far as emissions are concerned (not that there is no impact, it would just be ridiculously low impact).

      Biodiesel (as usable in my VW Jetta) is only a little less efficient than petrol / oil based diesel. Mileage is about 5mpg lower or so, but you have to make sure the biodiesel is clean of other contaminants which can be a bit laborious depending on the original source. Of course most people I am aware of will typically use an 85/15 blend for better performance (15% regular diesel).

      As far as emissions go, I don't think it's too much different but I don't know much about that. I guess it would entirely depend on how "clean" and viable the input is.

      In any case, if we can turn something which truly does not have a better use other than to be cleaned (at great expense) and sent back into the biome into a usable fuel at less expense I fully support research into it. It seems to be much smarter than ethanol where suddenly the price of fuel becomes linked to the price of food. We honestly don't currently have a better use for human sewage anyways considering it is not considered fit for fertilizer either. Besides, if this comes to America just think of how much fatty acids are already present in the McSewage, or how we could just re-introduce Olean oil if we needed to increase production (how's that for a disgusting thought?).

      - Toast

      • Posting in reply to my own post... Bad form, I know. Just a couple of details since this is something which personally interest me...

        Considering I get about 45mpg on my 2006, averaged over 600 miles driving around Chicagoland, on regular diesel (low of 35 in bad traffic and a high of around 52 on the freeway) losing 5mpg is a trade I would be willing to make to switch off of diesel and onto biodiesel (100%)... Now if only I could just pump it into my tank at the gas station instead of having to procure and

        • by sumdumass (711423)

          They used to claim that the increase lubrication caused greater fuel efficiency in the bio form. Diesel is a lot like gas where it is formulated in different types in different parts of the country at different times of the year. This claim may be just something that is regional or perhaps only applicable during certain types of the year.

          As for restaurants, Every one I worked at sold the waste oil to make soap and other supplies from. At a family style restaurant I was part owner of once, we got something l

          • by Anonymous Coward

            Actually there's less lubrication, at least in the biodiesel that's home produced. Diesel DOES have different formulations as well since if it did't it would turn to a gel in the Winter and nothing would run until it was warmed.

            As for stories of free oil - that's mostly B.S. IMO. Every restaurant n my area has their waste bin locked and signs notofying folks it's NOT free. It's used to make fuel and yeah soaps etc. using the glycerin. I laugh at people who think they can just grab it and use it - sure as he

      • Re:Still.. biofuel (Score:5, Interesting)

        by ldobehardcore (1738858) <steven.duboisNO@SPAMgmail.com> on Friday August 31, 2012 @03:21AM (#41187195)

        Regarding Emissions:

        Biodiesel is much better for the air. While it certainly does produce CO2 in nearly the same amounts per unit burned, it is unlikely to contain sulfur in measurable amounts. How much sulfur is in deep fryer oil, or sewage? Practically none, since it's poisonous. People don't eat it in more than trace amounts.

        So while Biodiesel is still not great for greenhouse emissions (unless it's balanced. Plant a tree dammit!), it's great for the breathing air of critters like us, compared to petroleum derived diesel. And if you clean it so it burns better in your engine, it's going to be much lower in particulate emissions as well.

        If sewage derived biodiesel is scalable, (and it looks like it might be), this could mean the end to all the shit we put up with going to war for petroleum.

        • Re: (Score:2, Interesting)

          by Anonymous Coward

          Biogas from waste water treatment plants (WWTPs) do contain sulfur, and the amount can vary a lot. Basically it depends on type of water treatment plant and the chemical (if it uses chemicals) used. In some cases reports have indicated more than 1000 ppm of H2S in biogas, but generally it's approximately 0-100 ppm.

          The sulphur does come from waste and some from water as well. According to Wikipedia, human body (70kg) contains approximately 140g of sulphur. It's necessary component for living cells. So sulphu

        • by drinkypoo (153816)

          Biodiesel is much better for the air. While it certainly does produce CO2 in nearly the same amounts per unit burned, it is unlikely to contain sulfur in measurable amounts.

          But sulfur has been stripped out of diesel, too.

          Biodiesel is carbon-neutral but results in slightly more nitric oxides so it has more acid rain potential than gasoline but in theory should do lower overall environmental damage. Long-term, we really need EVs. Or maybe one day hydrogen fuel cells will become practical, but that includes a better way to "make" hydrogen.

        • by Anonymous Coward

          Biodiesel user here. It actually is great for greenhouse emissions. There may be an similar amount of CO2 produced when you run your car on diesel or biodiesel, but that CO2 is removed from the atmosphere by the plants grown for the biodiesel feedstock, so there is no *net* increase in atmospheric CO2. With regular diesel, you are digging it out of the ground and adding to atmospheric CO2.

        • So while Biodiesel is still not great for greenhouse emissions

          Biodiesel is just fine for greenhouse emissions. It's carbon neutral, an analogue to the photosynthesis loop. It goes like this:

          Sun powers plants, that's your energy in. Plants grow and pull carbon from the air and nutrients from the soil. Harvest plants. Press oil from the plants and make biodiesel. Return the leftovers to the land for fertilizer. Burn biodiesel. Biodiesel returns CO2 to the atmosphere for the plants to use back in

      • Re: (Score:3, Informative)

        by dkuntz (220364)

        The issue I see is that newer VW TDIs (with the common rail system) is not designed to run on anything higher than B5 (95 Diesel/5 Bio). With my 2012 Jetta, if I use anything higher, they can void my warranty, and they are able to tell. Which sucks cause the station right near me that does Diesel does anywhere from B1 to B11, no notice as to what it is at that time. The problem here is the point in which biodiesel combusts, as compared to straight diesel. To be "clean burning", which VW Diesels are, the

      • by Shotgun (30919)

        So don't use this product in cars. Use it for home heating oil, which is just diesel with the road use taxes removed (at least in the US).

    • The better comparison might be between the emissions that would normally be produced by allowing the raw material to decompose naturally and the emissions from turning it into biodiesel and burning it. They would be different gasses, so the comparison would need to account for the different greenhouse effects. I understand that methane is one of the worse ones, so your emissions on this type of biodiesel might come out negative.
    • by Anonymous Coward

      The CO2 part of the emission is eliminated here because the CO2 being released was already taken from the atmosphere in the first place so there is no new CO2 being produced here. Other emissions are probably not reduced, but those are really only a problem for the immediate area surrounding the car. If you use this fuel to generate electricity in a central place with no people around and a very high smokestack, then the emission problem really would be solved by this technology. That plant also could be de

  • Despite the bullshit in the summary, biodiesel is NOT compatible with all diesel engines.

    In some VW TDi engines biodiesel can and will cause problems in the fuel injection system and the EGR
    system.

    Of course I work on these cars for living, so I am sure one of you keyboard commandos will tell
    me I am wrong because you heard it on a website somewhere. Hey, fuck up your own TDi, I could care
    less. Just don't come to me for sympathy.

    • by shuz (706678) on Friday August 31, 2012 @02:30AM (#41186999) Homepage Journal

      To expand on this, in new TDI's from Audi/VW at certain intervals raw diesel is injected into the cylinders post burn to heat up the particulate filter and burn off collected carbon. Because of this the raw diesel fuel mixes a little with the oil. For petroleum based fuels this is not a problem as the synthetic oil is designed to allow this to happen. Unfortunately biodiesel is a really great engine cleanser. The problem is that when biodiesel above 5-10% mixes with the synthetic oil the oil is diluted and loses its ability to adhere to the cylinder wall and prevent friction. I think most people understand the basic concept of running an engine without oil. My understanding is that a person could run up to 20% biodiesel if they are willing to make very frequent oil changes, say every 5k miles. But at ~$60 a change it may seem pricey for you.

      • What if biodiesel users implemented a more viscous oil? Would that help? I'm honestly curious.

        Wouldn't a higher viscosity oil dilute less quickly, making it last longer? Or would it still cause problems by not lubricating the engine enough, and letting heat build up from friction anyway, since the oil doesn't move as quickly?

        • It is unlikely to dilute less fast - it would be mixed in the same proportions.

          Additionally, running thicker oil will reduce engine efficiency, which is why you run a diesel in the first place.

      • by drinkypoo (153816)

        In fact this is always a problem because there is always some blow-by. Running biodiesel means more frequent oil changes because the blow-by from biofuel ruins petro-lube, and vice versa. Supposedly you can get bio-based crankcase lube in europe. I haven't looked in a while but last I checked there was nobody importing it to the USA.

      • The bigger problem is that the fuel injection system (in all new common-rail Diesels, not just VW TDIs) operates at such high pressures that the waxes present in Biodiesel tend to gum it up and break it. Given that the fuel injection system on a new Jetta costs $10K to replace, using biodiesel in such vehicles is not a wise choice.

        Older Diesels, such as my 1998-model VW, do just fine on Biodiesel -- and get better fuel economy than the new ones, to boot!

    • by Gordonjcp (186804)

      It seems to be an issue with common-rail diesels. The Bosch pumps fitted to old VWs and PSA XUD engines aren't bothered in the least, but XUDs with Lucas pumps won't last the pace. Anything with a common-rail system has big warnings in the manual not to use it with biodiesel, which seems like a step backwards.

      It annoys me slightly that the heavy, lumbering, clattery 2.5 litre 200bhp turbodiesel getting 40mpg in my old CX is cleaner than the 50mpg 1600cc engine in my van...

  • That's how... (Score:4, Interesting)

    by Vintermann (400722) on Friday August 31, 2012 @02:47AM (#41187067) Homepage

    To turn the sludge lipids into biodiesel, the researchers heated them with methanol.

    Yeah, that's basically the way all biodiesel is made... But the problem with biodiesel isn't just the price of feedstock (used fryer oil is cheap enough already!), it's the price of removing stuff from the feedstock that would make the biodiesel of unacceptably low quality (free fatty acids, BCBs).

    • by Anonymous Coward

      RTFA - the came up with a cheaper process to do that too.

  • by MtViewGuy (197597) on Friday August 31, 2012 @08:11AM (#41188465)

    ....If you want to make biofuels on a truly huge scale, there's only one source that actually makes sense: oil-laden algae.

    Since some forms of oil-laden algae can grow in seawater, that right there means anywhere near an ocean the algae can be grown on a very large scale without the enormous expense of finding a source of fresh water. And the waste from processing oil-laden algae into biodiesel fuel can be processed further into either ethanol or turned into agricultural fertilizer.

    • by drinkypoo (153816)

      It's "all" oil-laden (anything you'll encounter in typical conditions) and we already know that you get the most production by just letting nature colonize your ponds. Then you don't have to dick with Ph or anything, just pump the water in.

      • by jamstar7 (694492)

        It's "all" oil-laden (anything you'll encounter in typical conditions) and we already know that you get the most production by just letting nature colonize your ponds. Then you don't have to dick with Ph or anything, just pump the water in.

        So, feed the algae on sewage, let it 'harvest' the lipids and oils needed for biodiesel, then harvest & process the algae? Should be good for a couple mil in development studies...

        • by drinkypoo (153816)

          So, feed the algae on sewage, let it 'harvest' the lipids and oils needed for biodiesel, then harvest & process the algae? Should be good for a couple mil in development studies...

          We've spent the money already, take a look back [nrel.gov] at it.

    • by cusco (717999)
      I've heard this idea presented before, and it scares the ever-living carp out of me. As if an oil spill isn't bad enough, now we're going to have an oil spill that reproduces on its own? All it will take is a dike collapsing in a storm. Yikes.
  • Great anime from South Korea (coincidence?)

    central to the plot was recycling poop into fuel when the world's fuel ran out.
  • ...the first time in human recorded history there is a mathematical proof with which to fuel further human population growth and development that the Oil and Gas industry can sell back to us at extremely high profits

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