Sewage Sludge Biodiesel Costs Just 10¢ a Gallon More Than Petrol

by , 06/01/10

sustainable design, green design, renewable energy, green power, biofuel, poo power, waste treatment, sustainable fuelPhoto courtesy American Chemical Society

The key difference between biofuels that are truly green and those that aren’t is the source material: is it genuinely waste, or is it something like food or virgin wood, that could be put to better use? Well, there’s one source about which there can be no doubt: sewage sludge. And a new study says that this poo-power can produce biodiesel that costs just 10 cents more than conventional diesel.

sustainable design, green design, renewable energy, green power, biofuel, poo power, waste treatment, sustainable fuelPhoto by bjornmeansbear

Every year, Americans generate seven million tons of sewage sludge — the semi-solid stuff that remains after wastewater is treated — and disposing of it is a real mess. Adding oil-producing microorganisms and processing the results into biodiesel could kill two turds birds with one stone, generating roughly seven billion gallons of fuel at just $3.11 a gallon. Conventional diesel costs about $3.00 a gallon.

The best practices for getting biodiesel this way have hardly been worked out yet, according to the study by EPA scientist David Kargbo. Among the biggest problems is finding a way to collect sludge that is high in lipids — the material the reaction uses — ensuring that traces of pharmaceutical chemicals don’t make it into the fuel. Finally, regulators haven’t even begun to assess what it would mean to transfer large amounts of sewage sludge to private companies for processing into biodiesel.

Via Science Daily

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  1. Researchers Transform S... September 27, 2010 at 3:31 pm

    […] be expanded to other reclamation facilities in the state. And with 700,000 metric tons of dried sludge generated each year in California alone, there’s a huge opportunity to generate low-cost, […]

  2. aligatorhardt August 6, 2010 at 10:31 am

    I agree with Unorthodox that avoiding lengthy transportation and containment would add efficiency. A nearby location for processing could allow direct piping of wastes to the bio-fuel facility. I would expect property next to the sewage plant would be low in demand and price. For only 10 cents a gallon more than regular diesel the savings in disposal of the wastes would make the process desirable. Petroleum prices will continue to climb but this process would be more stable in price.

  3. Stanford Scientists Tra... July 27, 2010 at 1:52 pm

    […] a pretty elaborate way to process sewage waste: Stanford researchers propose using anaerobic bacteria to break it down, producing nitrous oxide or […]

  4. Ameer ahmed July 27, 2010 at 2:28 am

    we have calcium sulfate sludge(Acid neutralization) to be reuse or sale.
    please give suggestions

  5. Nanotechnology Makes Po... July 23, 2010 at 2:01 pm

    […] may be strange to think of poop as the holy grail of anything, but poop power is a coveted form of renewable energy because it eliminates waste — which we don’t want — while producing electricity, which we […]

  6. sstvp June 6, 2010 at 12:22 am

    Well… you really don’t want to put sewage sludge directly on food-producing land. All kinds of health problems occur, as China can attest.
    Sludge has to be sterilized before it reenters the environment, and burning it as biodiesel seems a better way than using petroleum to burn sludge down to ash that is used as fertiliser now.

  7. gerrymetal June 2, 2010 at 6:45 am

    Alternatively…why not continue to use human waste as fertiliser for our food crops?? this is a practice going back thousands of years (in fact its the main reason that countries like China had such high nutrient crop yields as far back as 500BC).
    This may seem gross but when you think about it using human waste to grow new food recycles all the nutrients we pass through our bodies and conserves precious water resources used in traditional processing and waste-water treatment.
    It also eliminates the need for chemical fertilisers…

  8. perfectcirclecarpenter June 2, 2010 at 1:16 am

    Has anyone ever compared the energy usage of an incinolet (1kw per “flush”) to the energy required to transport sewage, treat water, and then harvest sludge?
    If you ask me, it just makes more sense to “eliminate” all contact of poo with our limited fresh water. The ash still makes great fertilizer in your rose garden.

  9. unorthodox June 1, 2010 at 6:32 pm

    Instead of transporting the sewage wouldn’t it be better to add on to the existing plant? Turn it into a sewage plant/conversion plant. Keep the sewage industry commercial adding to green jobs.

  10. rgarzamarcos June 1, 2010 at 6:17 pm

    … great gas lamp you have ther, but wait.. what\’s that smell?

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