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Figure 2 - Food
waste production and
management techniques
from 1960-2017 in USA. 17

Figure 3. - Total emissions from food waste compared to
the top 20 GHG-emitting countries .
18

Animal Manure
Animal manure is another common feedstock for
AD systems. According to the USDA, in the USA
animal feeding operations (e.g., feedlots, dairy
farms, poultry houses, and other agriculture faci-
lities) produce around 335 million tons of manure
annually - much of which is deposited in lagoons
19
or land applied emitting methane, ammonia, hydro-
gen sulfi de, and carbon dioxide. 20
The potential feedstocks needed for the successful
operation of an of AD are not only plentiful and re-
newable but as evidenced above can be incredibly
harmful when mishandled with any number of as-
sociated environmental and business challenges.
This highlights the dual benefi t of AD systems:
While producing RNG, AD systems divert un-
desirable waste materials from landfills and la-
goons.

Figure 4 - Lay-out of an AD Plant transforming 30,000
tons/y waste in 7,000 tons/y of Biogas with versatile
outputs (see fi gure 5).

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