Paper beats stone?
It will seem impossible but today we can write directly on sheets that look like paper, but which are actually produced from stone dust, precisely calcium carbonate, held together by high intensity polyethylene.
Stone paper is a paper mainly composed of calcium carbonate (waste stone, marble and tiles). Powdered calcium carbonate (80%) is mixed with non-toxic high-density polyethylene (HDPE) (20%) to create candy-sized white balls. In a completely dry process that does not use acids, bleach or water, the pellets are compressed into a material that resembles traditional paper.
It is a tear-resistant product, infinitely recyclable (unlike the 7 times of cellulose paper), with lower ink absorption (30% less) during printing, water resistant and photodegradable. Furthermore, during the processing phases, an amount of energy equal to about 50% is saved compared to the production of traditional or recycled paper.
It is 100% water repellent. Liquids, including oil, do not alter its structure as it does not contain wood fibers which absorb liquids, even small drops, and deform the product by destroying traditional paper in seconds. That’s why it’s so durable over time.
No chemical treatments are required. In the production of traditional papers it is necessary to use many chemical substances both to whiten the natural fibers and to prevent light from discoloring the paper, as happens, for example, for newspapers. On the other hand, no chemical product is needed to produce Stone Paper: the materials used are already white at the origin and the high density polyethylene is colourless.
Stone Paper combines the advantages of paper, as it is easily printable, and of photodegradable plastic as it decomposes without polluting the environment within 9-12 months.
Summarizing the characteristics of the impact on the environment:
- Low water consumption.
To produce 1,000 kg of traditional paper, 35,000 liters of water are required, of which approximately 2,770 liters are consumed without the possibility of reuse. The production of 1,000 kg of Stone Paper, on the other hand, saves the amount of water needed by 50 people for a month.
- Energy savings of 85%.
The energy that stone paper saves is equivalent to the consumption of a year and a half of an average family. Thanks to the type and high efficiency of the production process, only 860 kWh are needed to produce 1,000 kg of Stone Paper, while 5,670 kWh are needed for traditional paper.
- Reduced CO2 emission.
The carbon footprint, i.e. the carbon footprint of Stone Paper, is 67% lower than that of traditional paper: for one ton of Stone Paper the CO2 emission is 482 kg, while that of traditional paper is 1,431 kg . Using Stone Paper, the reduction of the carbon footprint per 1,000 kg of paper is equivalent to 4,520 km traveled by car: the distance between Naples and the North Cape.
- The paper that saves trees.
To produce 1,000 kg of traditional paper, 18 trees are needed, while no trees are cut down to produce Stone Paper.
In the light of these data, paper might continue to beat stone in Rock, Paper, Scissors game, but in the paper industry and from the point of view of environmental impact, stone paper beats traditional paper.
Not just Paper stone: more and more alternatives to wood pulp paper are being created every day, from a whole range of materials such as cotton clothes, fruit, seaweed, herbivore dung. We explore it in depth in the article Materials With Which to Make Paper (alternatives to trees).