5 ms·

Methane is going to come out of sewage whether we process it or not, and methane itself is a greenhouse gas. It's not going to come out of the ground without h

by enkid 6y ago

Methane is going to come out of sewage whether we process it or not, and methane itself is a greenhouse gas. It's not going to come out of the ground without help (in the quantities we are using).

loeg 6y ago
Sure, burn that methane. Is there enough of that to many any significant impact on energy needs?
- brtkdotse 6y ago
  Most busses and taxis in Sweden run on it, so there’s that
  - jnurmine 6y ago
    And the gas comes from biowaste, which is actually nice, because municipalities which have the most effective ways of collecting and processing biowaste can export the resulting biogas to e.g. surrounding municipalities and in this way generate income to run things for everyone. This means waste must be sorted somehow, but this is a rational thing to do anyways. And it pisses me off immensely to see some idiots throw plastic bags or non-food waste to the biowaste bins. There are signs in many languages and even with pictures, but some people still manage. Such biowaste cannot be used for gas generation, so it's kind of hurting all the inhabitants.
    - brtkdotse 6y ago
      Household waste comprised a minuscule percentage of the total substrate. The majority is sewage and food processing refuse. Source: my wife used to work at a biogas plant
      - jnurmine 6y ago
        Maybe not all plants are alike? According to VafabMiljö [1], who runs the local biogas facility, in the year 2020 they processed 16157 tons of household biowaste, i.e. 66% of entire processing that year. The other stuff was sewage sludge and slurry from packaged/unpackaged food items (total of 8246 tons). 16157 tons of household biowaste turned into gas to run buses with and not dumped into a landfill is a good thing. In 2012 the municipality collected 60% of overall food waste to turn it into biogas. Back then they hoped to reach 80% eventually. [2] I didn't find newer collection numbers (they are somewhere, I just stopped iterating), but the number can only be higher today. [1] https://www.vafabmiljo.se https://www.vafabmiljo.se [2] Naturvårdsverket rapport 6518, September 2012 (ISBN 978-91-620-6518-8).
brtkdotse 6y ago
Methane is an incredibly potent greenhouse gas, however it breaks down rather quickly. Like I said in a sibling post, the big advantage is that biogas is Net 0 carbon wise as you’re reusing carbon already in the carbon cycle
- mlyle 6y ago
  ... it's incredibly potent as CH4... and then it "breaks down" into CO2 and H2O. I think enkid's point is agreeing with you: might as well burn that sewage CH4 for energy-- you end up with the same CO2 in the end and less CH4 in the atmosphere in the short term.

by enkid 6y ago

Methane is going to come out of sewage whether we process it or not, and methane itself is a greenhouse gas. It's not going to come out of the ground without help (in the quantities we are using).

loeg 6y ago

Sure, burn that methane. Is there enough of that to many any significant impact on energy needs?

brtkdotse 6y ago
Most busses and taxis in Sweden run on it, so there’s that
- jnurmine 6y ago
  And the gas comes from biowaste, which is actually nice, because municipalities which have the most effective ways of collecting and processing biowaste can export the resulting biogas to e.g. surrounding municipalities and in this way generate income to run things for everyone. This means waste must be sorted somehow, but this is a rational thing to do anyways. And it pisses me off immensely to see some idiots throw plastic bags or non-food waste to the biowaste bins. There are signs in many languages and even with pictures, but some people still manage. Such biowaste cannot be used for gas generation, so it's kind of hurting all the inhabitants.
  - brtkdotse 6y ago
    Household waste comprised a minuscule percentage of the total substrate. The majority is sewage and food processing refuse. Source: my wife used to work at a biogas plant
    - jnurmine 6y ago
      Maybe not all plants are alike? According to VafabMiljö [1], who runs the local biogas facility, in the year 2020 they processed 16157 tons of household biowaste, i.e. 66% of entire processing that year. The other stuff was sewage sludge and slurry from packaged/unpackaged food items (total of 8246 tons). 16157 tons of household biowaste turned into gas to run buses with and not dumped into a landfill is a good thing. In 2012 the municipality collected 60% of overall food waste to turn it into biogas. Back then they hoped to reach 80% eventually. [2] I didn't find newer collection numbers (they are somewhere, I just stopped iterating), but the number can only be higher today. [1] https://www.vafabmiljo.se https://www.vafabmiljo.se [2] Naturvårdsverket rapport 6518, September 2012 (ISBN 978-91-620-6518-8).

brtkdotse 6y ago

Methane is an incredibly potent greenhouse gas, however it breaks down rather quickly. Like I said in a sibling post, the big advantage is that biogas is Net 0 carbon wise as you’re reusing carbon already in the carbon cycle

mlyle 6y ago
... it's incredibly potent as CH4... and then it "breaks down" into CO2 and H2O. I think enkid's point is agreeing with you: might as well burn that sewage CH4 for energy-- you end up with the same CO2 in the end and less CH4 in the atmosphere in the short term.