Yep - methane digesters / production can be used in landfills, sewage treatment plants, animal farms, and purpose made gas production from many types of biological waste. After the methane is made, the resulting material has fixed nitrogen, which means it is not water soluble (and won't wash away in the first rain), making it a high quality fertilizer. Which allows you to NOT make fertilizer from natural gas, so it can eliminate TWO sources of carbon dioxide.
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