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Science Technology

Wastewater Into Energy 54

Posted by michael
from the stand-upwind dept.
fenimor writes "A lot of electric energy could be produced from a city's wastewater, researchers at University of Toronto have discovered. The research revealed that the wastewater contained enough organic material to potentially produce 113 megawatts of electricity - 5 times more than required to operate wastewater treatment plants."
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Wastewater Into Energy

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  • by Anonymous Coward
    belongs in waste water.
  • sad truth (Score:2, Insightful)

    So many cool techs.. great!
    But if it doesn't turn out to make (or save) money, it will go nowhere.
    Capitalism (and consumism) is ruining the planet.
    • Actually, capitalism and consumerism aren't that bad- as long as you don't have the unholy union of government that is the corporation.
    • Re:sad truth (Score:5, Interesting)

      by cpeterso (19082) on Tuesday September 21, 2004 @06:14PM (#10314145) Homepage

      if it doesn't turn out to make (or save) money, it will go nowhere. Capitalism (and consumism) is ruining the planet.

      Actually, capitalism will SAVE our planet. If people value living on a nice, clean planet, they will pay for such benefits. The problem is not capitalism. The problem is the environment is a market externality. It's the classic tragedy of the commons: everyone uses (up) the environment, but no one PAYS for it. This is usually because governments disallow or dismiss environmental class action lawsuits.

      The Soviet Union was on of the world's worst polluters. Today, the US government is the worst polluter in the country. Why are they allowed to pollute? When you write the rules, they don't have to apply to you. For some reason, most environmental and endangered species protection laws DO NOT apply to the US government or military! >:(
      • Re:sad truth (Score:3, Interesting)

        You're damn right that's capitalism. We all started out living on a nice clean planet. Then the capitalists got ahold of it and polluted parts of it up. And now, if we want to live on a clean planet, here's a capitalist right on schedule, promising to sell us one. And you know he's right, because the commies were terrible polluters. So what's wrong with this picture?

        • No, he is saying that if you want a cleaner planet or just a cleaner country. You will have to pay for it (in dollars). Someone will have to pay for the cleaning crew, stricter laws and so higher prices.

          However people tend to go for less environmental friendly products because they are cheaper. So in terms of capitalism it's their own fault for the messed up enverioment.
          • Re:sad truth (Score:4, Insightful)

            by MarsDefenseMinister (738128) <dallapieta80@gmail.com> on Tuesday September 21, 2004 @07:12PM (#10314611) Homepage Journal
            I know what he's saying, but I'm offering another way to look at it. Every time someone asks us to cough up some money to clean up the environment, we have to ask ourselves who polluted it in the first place. We had a clean environment, and it was polluted because someone decided that the future could suffer so that a profit could be made today. This is a crime, and now to say that it's the natural order of things that we have to pay money to clean our environment is putting things backwards.

            It's extortion. I'll stop polluting your environment and/or beating you up if you pay me some money. We shouldn't have to take it. You know who should have to pay for pollution? The capitalists. If they want to pollute, they should have to pay for it, not us.

            • In short, using capitalism to fight pollution is fine, as long as the pollution becomes part of the equation.

              Every polluter must pay for cleanup. Make the cost of removing pollution part of the cost of every product you use and buy. *Then* capitalism will have an effect, and people will choose to buy the cleaner things because they're cheaper.

              If that doesn't happen, and producers get to pollute for free, capitalism has no mechanism to deal with it.

            • Extorting the environment for short-term profits is akin to social security and the [US] national deficit. It is a tax on the youth (or unborn). We are shifting our problems to the future so our kids and their kids will have to fix them. Same as our parents did to us.

              Unfortunately, it will probably take a combination of government regulation and the pressures of capitalism to force us to clean up any of it. Until then, there are just too many people who don't seem to care. As long as people care mor
              • I'm not sure what you mean by the social security thing, but the national debt is caused by similar attitudes.
                • Social security is basically* a way for your grandkids to help pay for your retirement. As long as the population was growing quickly (baby boom) the younger generation did not suffer greatly. However, now there is a great number of people reaching retirement age and the ratio of people collecting social security versus the people paying into social security is starting to/ about to crash.

                  So far the only actions that have been taken to "fix" this is to raise the age to collect retirement benefits. (I
                  • OK, I understand what you are saying now. Offtopic, but it's interesting anyway. The date that Social Security is projected to run out of money is still very far off. So far off that I won't be around to see it, and I'm only 35! The articles that say SS will be bankrupt by 2029 are wrong. If you read closely, they are actually saying that SS will start to pay out more money than it takes in in 2029. The time for it to run out of money completely is much further off. And, even if we reach that point, everyth
                    • Yes, definitely offtopic (this is /., right?). I don't want to see it disappear, I just recognize that there are problems. I just hate that it has become one of the many 3rd rails in politics.

            • Polluters would not be able to afford to pollute if consumers stopped buying the polluters' products. Consumers should stop financing polluters! I'm a vegetarian because I think meat production is wasteful and environmentally damaging. I am voting with my dollars. The market is greedy: it will follow the money. Look at all the hyped-up organic food markets and hybrid cars. The market is listening (albeit slowly).
      • cpeterso makes a good point about market externalities. An excellent book that points out how to capture market externalities and use market forces to protect the environment is "Costing the Earth" by Frances Cairncross (sp?), a former environmental editor for the Economist. Does a good job of showing how a carbon tax, eco-tourism, market-based pollution trading, etc. could work. Also does a good job showing why recycling can often be a counterproductive solution (ie, generating a lot of material that no on
      • Re:sad truth (Score:3, Insightful)

        by Yokaze (70883)
        > If people value living on a nice, clean planet, they will pay for such benefits.

        If they can afford to. The problem is, those people who don't care have more money to profit from, hence have an economical advantage, hence are more likely to decide, wether there will be a nice, clean planet.

        Companies, which exploit land and its resources in an long term unsustainable way have a faster growth than companies, which don't.
        This economical advantage will drive the latter companies into a fringe market, whe
    • Re:sad truth (Score:3, Informative)

      by FooAtWFU (699187)
      When I went to the local water treatment plant, they had a set of turbines to burn the gas which they could extract from the wastewater. They weren't using them. It was cheaper for them to just buy electricity as they needed.
  • Splashplop! (Score:5, Funny)

    by contagious_d (807463) on Tuesday September 21, 2004 @06:00PM (#10314035) Journal
    According to the article, "Any recovery of potential energy above that can be returned to the grid.". I wonder if there is any way you could set this up so that you get credits on your power bill when you exceed a certain amount of waste. That would be awesome! Like getting paid for your hard work in the bathroom! Oh yeah, another thing... this is a story about poop. That is also awesome.
  • Methane gas (Score:3, Interesting)

    by BrookHarty (9119) on Tuesday September 21, 2004 @06:01PM (#10314039) Homepage Journal
    Man I'm dense, I'm wondering how they turned shit into power, had to RTFA to find out its methane gas from microbe processed organic material. 1 More line on the Slashdot topic and I wouldnt have had to read the article, the article was that small....
  • Pretty old news (Score:5, Informative)

    by HotNeedleOfInquiry (598897) on Tuesday September 21, 2004 @06:02PM (#10314049)
    About 10 years ago I was elected to the board of directors of a wastewater district. We captured the methane from the digesters and used it to drive the aereation (sp) blowers. Saved about $30k/month in electricity. Most of the time surplus methane had to be flared off.

    Now some places also dewater the sludge and burn it to generate energy. Quite a bit more messy and polluting than just using the methane.

    All this technology has been around for about 20 years. It's just complicated and sometimes polluting. There's almost always regulatory issues about who can sell power to who, who can burn what where and so on.
    • When I saw this article I was afraid it was another "microbial fuel cell" thing.

      I don't see any reason why dewatered sludge couldn't be fed through an anything-into-oil plant [changingworldtech.com] and converted to energy more cleanly than by incineration.

      • That would just make too much sense - how dare you!

        This would also be a great opportunity for large livestock farmers - most of the time they have a surplus of "organic waste matter" and have to scramble to find a place to till it into the ground. If they could sell it for conversion into oil - that's just a good idea.

        • That would just make too much sense - how dare you!

          Engineer-Poet, confounding /. with logic since 2004.

          This would also be a great opportunity for large livestock farmers - most of the time they have a surplus of "organic waste matter" and have to scramble to find a place to till it into the ground.

          I'm not sure how useful it would be for livestock farmers. In a city, pretty much everything that goes to the sewage plant is quite a distance from where it originated. Unless you can reduce the bulk of the

          • The problems with large scale livestock farming are that you need a pretty good chunk of land to "take the poop" from an operation. When you put too much manure of the fields, you end up with nitrate runoff which makes people downstream (and eventually the gulf of mexico) unhappy.

            I think that I read somewhere that some hog operations produce the raw sewage of a city of 30,000 people. When you get that much manure, disposing of it by tilling it back into the land becomes problematic, and converting it

            • The problems with large scale livestock farming are that you need a pretty good chunk of land to "take the poop" from an operation....

              I think that I read somewhere that some hog operations produce the raw sewage of a city of 30,000 people.

              They're called CAFOs [google.com], Concentrated Animal Feeding Operations. I suspect that these are only economical because they are allowed to dump animal waste with minimal or no treatment; if they had to pay for the remediation required of municipal sewage plants, they would ce

              • You could do the same with human waste if it was guaranteed not to have any non-organic nastiness (like other chemicals or heavy metals) in it. The trick is to have access to enough land to till it into. Too much manure can cause problems when it runs off during the spring.
                • You could do the same with human waste if it was guaranteed not to have any non-organic nastiness (like other chemicals or heavy metals) in it.

                  If your town has even one plating plant or other manufacturing operation in it, good luck. You'd need separate sewer systems for domestic and industrial, and guarantee that nobody dumps anything nasty down either a domestic sewer or a storm drain. I see this having two chances: slim and none.

                  This is one reason why I think thermal depolymerization has a bright fut

                  • That's what I was trying to get at, but didn't say it so well.

                    You could also set up a pretty good system for it by doing taking corn and making ethanol and feed stock. The feed stock can be given to cattle (and hogs? not sure about that) which will produce lots and lots of manure and meat. A portion of the manure can be tilled back into the surrounding land, the balance can be taking to the depolymerization plant. After slaughtered, the remnants of the cattle and hog carcasses (that which is not used

      • I don't see any reason why dewatered sludge couldn't be fed through an anything-into-oil plant and converted to energy more cleanly than by incineration.

        Equipment I designed does the heavy lifting for the heater jackets used in that stuff. A year ago I was sent down to Carthage, MO to the first large-scale facility these guys built for Butterball... It was a mixed emotion trip... I was thrilled that I got to see this stuff up close and that something I'd designed was in it, but at the same time the re

      • I don't see any reason why dewatered sludge couldn't be fed through an anything-into-oil plant and converted to energy more cleanly than by incineration.

        My employer is a water and sewer utility. Allow me to inject some ugly realities in to this beautiful theory.

        First, while most of us think of toilet output when we think of sewage, the reality of most municipal wastewater is that it has loads of soap in it. In fact, the smells you encounter most often at a wastewater plant are really kind of a musty

        • First, while most of us think of toilet output when we think of sewage, the reality of most municipal wastewater is that it has loads of soap in it.

          I was talking about sludge, which is quite a bit removed (and concentrated) from the state of raw sewage. As for the soap, if you can separate that and feed it through thermal depolymerization it would be good. Lauryl sulfate (derived from dodecanol) ought to be just the kind of thing that produces good hydrocarbons as output. Ditto stearates.

          The beauty of

          • I was talking about sludge, which is quite a bit removed (and concentrated) from the state of raw sewage. As for the soap, if you can separate that and feed it through thermal depolymerization it would be good. Lauryl sulfate (derived from dodecanol) ought to be just the kind of thing that produces good hydrocarbons as output. Ditto stearates.

            Uhh, what about bleach? What about phosphates? Yeah, I know, the really widespread uses of phosphates has been banned, but you'll still see some evidence of it h

            • Uhh, what about bleach? What about phosphates?

              I'll bet that hypochlorite winds up as chloride just from reacting with organic stuff. Dunno what you are asking about phosphates, and I will be the first to admit that I don't know what happens to them in the thermal depolymerization process. The articles I've seen would appear to suggest that they wind up among the solids.

              Anaerobic digestion doesn't like bleach (kills the bugs) and will pass the phosphate through the system. You'll still have to dispose of

  • by Anonymous Coward
    The energy produced is pretty shitty.
  • Use the deorderized sludge in your tabletop nanofactory to make steak- after all, the atoms are the same, it's just the arrangement that is different.
  • Really!

    All they did was see what the caloric content of the sewage was, and said "If we can turn 20% of this into energy, we have a profit".

    where have I seen this before?
  • by cft_128 (650084) on Tuesday September 21, 2004 @06:35PM (#10314318)
    They are already doing this for dumps. They have been doing this in Michigan [solutions.ca] using Toronto's imported garbage, and it looks like another one is being developed near Montreal [canoe.ca]. It looks like the Montreal facility will power a paper plant, and if memory serves me correctly -- I can't actually find a link now -- the Michigan dump(s) are selling the power to the grid.
  • by EnergyEfficient (797153) on Wednesday September 22, 2004 @06:16AM (#10317244) Homepage
    Anerobic decomposition makes things beyond A carbon and some hydrogen. You get a few Nitrogen/Hydrogens and more Sulfur/Hydrogens. Both of these gasses when oxidized will make acids that will eat up the equipment. You can ruin an internal combustion engine in less than a day, and a boiler in a week if you don't have the boiler lined. Alot of energy is imbedded in our sewage, from the machines in the field that prep and harvest the food we eat, to the trucks that move that food to the pumps that move the water then the sewage to be processed. With good engineering, some of that energy can be reclaimed, but the researchers make it sound like the process is 'simple' when it is not.
  • Some moths ago, there were reports [slashdot.org] of using water from Lake Ontario for cooling. Maybe they can think of a combined solution.
  • The plant at ashbridges bay already uses anaerobic processes (on the sludge) to produce methane that is used in heating the plant.

    The article was a little simplistic. The reason that sewage treatment plants use aerobic processes for water treatment is that they are efficient ( 1 day residence time comapared to 30 day residence time) Anaerobic digestion can be used when you have seperated the solids from the liquids since they are a very small fraction of the total, and this is what is quite often done.

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