Food waste arrives at the plant
it's pre-treated and any remaining packaging is removed, it's then fed into
the digestion tank
here the waste separates into the two main products: firstly
there's methane and rather than being released into our atmosphere this gas is
captured and used to power
electricity generators. Over ninety percent of the electricity produced in
this way is exported to the national grid
the remainder being used by the plant itself, alternatively
the methane can be cleaned up and used as a vehicle fuel or fed into the
national gas supply
for use by homes and businesses. There is also a very useful byproduct,
heat, about a third of this is used to heat the AD plant itself
with the remainder often being used to warm local factories and other buildings
making the whole process almost self sufficient in power and heat
There's also an useful secondary product which comes from anaerobic digestion
this is a digest that sinks to the bottom of the tank, which is rich in
nutrients and nitrogen
which can be used as a soil improver and, with the cost of fertiliser going up all
the time, this is a great way of returning nutrients to the land
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