A Tool for Harvesting Metal

Emissions from various anthropogenic sources are likely to increase the heavy metal pollution in soils and make them infertile. For the growing world population, the renaturation of land by means of special phytomining hyperaccumulative plants could therefore become more and more important. The former endemic nickeltree Pycnandra acuminata could be grown in a way that it could also be cultivated in milder European climates. It can be used to regain the valuable nickel from the tree sap and simultaneously detoxify the soil. 

The Pycnandra acuminata tree is considered the most productive hyperaccumulator of heavy metal in the plant kingdom. An adult tree concentrates in different tissues, the bark, the leaves and in latex sap a total nickel content of about 37 kg.

student:Anna Freudenberg
project:urban mining – urban tooling

The Nickeltree Sap Tap

by Anna Freudenberg

2130: all natural ore occurrences on earth are exhausted and 45% of the soils are contaminated with heavy metals and have become infertile. At the same time though, new innovative methods for metal recycling have been developed.

Bob belongs to the so-called Generation A, he was born in 2110 in an era of upheaval, which should change the history of mankind on this planet forever. “Back then, everything was different…”, he hears his grandmother say. Then she begins to speak of the turbulences of the past decades, of the many wars and the feeling of how it is to watch the world go down before one’s own eyes – and to be so powerless at the ssame time. When Bob hears those stories, he is glad that he did not have to experience anything preceding his life: the collapse of the system, the political conflicts worldwide due to the scarcity of raw materials and the chaos of ecological rethinking. He, as a Generation A child, was born into a time of political peace. In the last minute, an ecological awareness for sustainability has unified states around the world, and for the past 20 years it has been all about: tidying up the environmental sins of humankind and promoting the regeneration of the earth. New models of circular thinking, recycling and a new way of dealing with the last resources that are still available have been created by a new way of thinking completely contrary to earlier politics. Bob doesn’t know it any other way. His whole life is a cycle, all processes build on each other. How could the generations before him have lived so ruthlessly and narrow-mindedly? When Bob thinks too much about this, he gets annoyed: “Why do we have to pay for the mistakes the generations made before our time? Why didn’t you do anything back then?” he asks his grandmother in a reproachful tone. The excessive and long-lasting extraction of ore, the deposits of major industries and the overfertilization have caused massive damage to the environment. If Bob wants to see intact pastures and arable land, he has to drive for hours. He only knows outdoor fruit and vegetable cultivation from pictures, now everything grows in vertical farms. But this is set to be changed by 2050, the new government has committed itself to the goal of renaturing 15 % of the soils contaminated with heavy metals. And this is where Bob’s business model comes in.

Bob is a phytomining expert and works as an entrepreneur on a nickel tree plantation with 150 nickel trees per plantation and 60 plantations throughout Germany. Through his work he witnesses the environmental impacts caused by humankind every day. The acids used for extracting the heavy metals from the soil have contaminated not only the soil but also the surrounding waters. The blue and poison green shimmer of the waters only looks beautiful from a distance. Drought, hardly any vegetation and huge areas of land unsuitable for agriculture. But as if that weren’t enough, numerous machines, such as excavators and drills, were simply left in the landscape. Normal plants cannot thrive here, only a few special species are able to grow under these conditions. As a result of global warming, Bob’s company cultivated hyperaccumulators as a new business model. Shrubs and trees are able to filter heavy metals from the soil and store them in their roots, leaves and sap. In this way, the soils can be detoxified and renatured. At the same time, the plants can also be harvested for regaining the valuable metals. Bob knows that it will be a long time before the earth has fully recovered and that even his children would probably not experience it any more. Although Bob has not chosen the time he was born in and often thinks of how beautiful it must have been on earth when everything was green, and in harmony with nature, when he goes to work in the morning with his tap, his bucket and his hammer and weighs the buckets filled with nickel juice in the evening, he still has the feeling of doing something useful. A new cycle of raw resources has begun with the harvesting of the nickel trees. Bob can resell the nickel to cooperating companies, just as he buys his tools from a surrounding company that has joined the circular economic system and produces new tools from the metallic legacies and unneeded large machines of the previous generation.