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Folke Günther folke@holon.se
The history of the living organisms conquering land
Nutrients in food
Nutrients in urine
Elementary nutrients
1. The situation in the primordial sea, 400 millon years ago
CREATCEAN SEA
Folke Günther folke@holon.se
What happened when the living organisms conquered land ?
Nutrients in food
Nutrients in urine
2 The situation after the first animals had conquered land
Folke Günther folke@holon.se
After just a few tousand years:
Folke Günther folke@holon.se
Where are the green fields my ancestors
were bragging about?
Folke Günther folke@holon.se
Interlude:
What are ’nutrients’ ?
’Nutrients’ are the essential elements needed to construct a body
These elements need to be attainable in right proportionsE.g.: You need four times more tires than steering
wheels to build a car
Folke Günther folke@holon.se
Without gaseous phases — must be transported as solids or liquids
More common in the Earth crust than in the body
The constituents of an animal (or vegetable) body:HHOOCCNNSSPPNaNaKKCaCa……6464
PP
HHOOCCNNSS
NaNaKKCaCa……6464
With gaseous phases — can be transported by the air
Nutrients
– phosphorus is the most important nutrient !
PP 10 times more common in the body than in the Earth crust
Folke Günther folke@holon.se
Nutrients are essential for life -- but phosphorus is the most
crucial
Folke Günther folke@holon.se
We need a method to use the phosphorus molecules several
times, without losses, so we can retain
phosphorus on land!
!
Folke Günther folke@holon.se
If we could transfer the phosphorus seamless from
organism to organism without losses to sea, we might solve it !
Folke Günther folke@holon.se
PO4
DNA
Urine
Consumption
Recycling
Reconstruction
The regenerative cycle, basic for living systems-- ecosystem level:
A seamless transport ofphosphorus from organism to organism!
Folke Günther folke@holon.se
Petrified newspaper found in the Cretaceous – Devon geosynclinal
Folke Günther folke@holon.se
PO4
DNA
Urine
Consumption
Recycling
Reconstruction
The regenerative cycle
High exergy
Low exergy
Folke Günther folke@holon.se
Ecosystem maturationA v a i l a b l e s o l a r e x e r g y
Immature system
• Low diversity• Annual plants• Competition• Parasitism• Nutrient leakage• Export• Fast change• Water export by drainage
Mature system• High diversity• Perennial plants• Co-operation• Mutualism• Nutrient circulation• On-site consumption• Slow change• Water export by evaporation
Mat
urat
ion
Mat
urat
ion
Folke Günther folke@holon.se
Present times
Folke Günther folke@holon.se
In preindustrial times, the farmland nutrients came from the meadows
Meadows
PO4
N
A certain amount of meadows were needed to feed the farmland
Manure
Feed
FoodFarmland
PO4
Phosphorus and nitrogen were collected by the meadow plants
Folke Günther folke@holon.se
During industrialisation, people moved into cities
Folke Günther folke@holon.se
PO4
N
The nutrients that went away to the cities never came back
Manure
Feed
Food PO4
These nutrients were collected by the meadow plants
In the cities, they also needed food, food from the farms
The food contained nutrients
The export led to an impoverishment of the agricultural land
Food PO4
Folke Günther folke@holon.se
PO4
Food
The impoverished land produced insufficient harvests
This triggered emigration
The industrialisation process mighthave been halted by the loss of nutrients from farmland
Folke Günther folke@holon.se
PO4
FoodPO4
Food
The situation was solved by the invention of artificial fertilizers
By that, the nutrients from the meadows became unnecessary
Even more food could be produced
Folke Günther folke@holon.se
PO4
Food
PO4Pollu-tion
PO4Pollu-tion PO4Pollu-
tion
PO4Pollu-tion
PO4Pollu-tion
But in the cities, the situation was becoming problematic
Folke Günther folke@holon.se
PO4
Food
PO4Pollu-tion
PO4Pollu-tion PO4Pollu-
tion
PO4Pollu-tion
PO4Pollu-tion
But the invention of the piping system eased the problems
Folke Günther folke@holon.se
PO4
PO4Pollu-tion
PO4Pollu-tion
However, at the end of the pipe, new problems were encountered
Plancton algae multiplied gladly from the new phosphorus
Folke Günther folke@holon.se
PO4
PO4Pollu-tion
PO4Pollu-tion
Already 50 years after the introduction of the process, it was realised that it was the phosphorus
that caused the problems in the water
Therefore, the politicians asked the technicians for a way to remove the phosphorus from the waste water
Folke Günther folke@holon.se
The problem
Naturally, they solved the problem in their usual expedient way
Large particlefiltration
Sedimentation
Sedimentation
Aeration
Flocculation Rotation
Filtering
Air
Aluminumsulphate
Sludge
Problem solved!
Folke Günther folke@holon.se
The problem
The problem to be solved was:
Problem solved!
”How to get (moderately) clean waterfrom the polluted water?”
This problem was solved .
Folke Günther folke@holon.se
Sludge
However, the question not asked was:
”How to recycle the phosphorus to avoid the problem?”
A large part of the phosphorus is contained in the sludge
Folke Günther folke@holon.se
Food
Food
Food
PO4
PO4
PO4
Most of the food to the city comes from very large distances
City
..while the phoshorus in the sludge is placed on a much smaller area
Folke Günther folke@holon.se
Food
Food
Food
PO4
PO4
PO4
This means that there will be an accumulation of phosphorusaround the city
PO4
PO4
PO4
PO4
After some time, the leakage from this heap will equal what is put on
The larger the amount accumulated, the larger the leakage
Folke Günther folke@holon.se
Food
Food
Food
PO4
PO4
PO4 PO4
PO4
PO4
PO4
At that time, the investment in water purification plants becomes meaningless
Folke Günther folke@holon.se
FoodFood
PO4 PO4PO4 PO4
PO4
PO4PO4PO4
City
PO4PO4
The HEAP-effect, in a saturated system
When saturated, the system leaks at the same rate as it is
loaded
With effiecient waste water treatment
methods (P precipitation),
this state is attained faster
Folke Günther folke@holon.se
HHamperedamperedEEffluentffluentAAccumulationccumulationPProcessrocess
The HEAPHEAP trap
Folke Günther folke@holon.se
HH ampered EE ffluent AA ccumulation P P rocess
(stored amount)
The HEAP trap:
(leakage)
kQ=J
QJ
QkQ(stored
amount)
Leakage
= input
Folke Günther folke@holon.se
The HEAP effectThe HEAP effect-- diffuse nutrient leakage
• Is an inevitable effect of urban agglomerations
• Is an inevitable effect of deficient nutrent recycling
• Can be solved by a changed settlement infrastructure– (or an extremenly expensive transportation system)
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