NUTRIENT
MINING
SUBWUM
(Sustainable Urban Biodegradable Waste Utilisation Modules)
"is
a process designed to absorb biodegradable waste streams and utilise
energy
and nutrients for the production of a diverse range of saleable
items and the
reduction of pollutants to acceptable social and environmental
levels"
The Process:
Stage
1 - Biogas Digestion
Basically,
biodegradable waste is added to enclosed chambers and decomposition
occurs due to anaerobic (without oxygen) bacterial digestion.
Pollution
levels decrease (up to 60%) in comparison with time and a rich
compostable sludge and methane gas is produced which can be used
for heating or electricity generation.
This
method is used extensively in Southeast Asia as a cheap form of
renewable energy for farmers.
United
Kingdom water companies including Severn Trent Plc have operational
plants and there are recorded instances for their use in Scandinavian
countries.
Stage
2 - Microalgae Production
The liquid waste is channelled into a Photo Bio-reactor, an intensive
algae production system situated in an enclosed controlled environment
that absorbs excess nutrients by the cultivation of microscopic
algae.
The
algae production reduces the organic pollution sufficiently (30%+)
to enable the output water to be of an optimum quality for aquaculture.
The
harvested algae can be used as a food supplement for fish and
plant culture.
Stage
3 - Ecologically Intensive Aquaculture
As
the system is modular there is an opportunity to culture a variety
of freshwater and saltwater species by enclosed re-circulation
technology.
Previous
biogas energy recovery enables higher air temperatures enabling
the production of warmwater species. One such example is the culture
of Tilapia, a native African herbivore which has a market value
in the U.K The fish will be cultured in rows of innovative hanging
bags of water stacked three tiers high.
Stocking
densities of up to 30 kg/m2 will be practised to maximise production
without compromising overall fish welfare
There
are also many other examples of commercial species particularly
saltwater shellfish which could be cultured in 'stand alone' systems.
Stage
4 - Hydroponic Horticulture
The term hydroponics is derived from the greek words hudor, water
and ponos, work. When combined these mean water-working and reference
to soil-less plant cultivation.
The
waste water from the aquaculture modules contain acceptable levels
of Nitrogen and Phosphorous for such cultivation, released in
fish excreta and leached out of uneaten food.
These
wastes will be used as an organic fertiliser in an aqueous solution
for uptake via the rooting systems, an example being tomato crops.
Hydroponic
horticulture will also utilise the majority of Carbon Dioxide
produced during the brewing process.
Stage
5 - Reed Bed Treatment Systems
Also
known as constructed wetlands.
All
waste leaving the building will be directed to outdoor engineered
reed beds forming wetland areas that host a medium for the growth
of bacteria congregating around the rooting systems. These break
down organic pollution to polish water to acceptable quality and
in many cases, lower than regulatory discharge standards.
Such
areas can also create valuable conservation reserves and increase
local biodiversity.
Microbrewery
Concept Images
The above computer generated images are an simulated impression
of how such a system and it's building might be perceived.
Courtesy of Letts Wheeler, Architects
|
