Shiro alga carta
Shiro Alga Carta is a paper made from algae which would otherwise clog up the Venetian Lagoon. The algae, which are harvested annually, are used in partial substitution of pulp and are combined with FSC fibres.
The creation of Shiro Alga Carta dates back to the early 90’s, when the Venetian Lagoon was clogged by an extraordinary algal bloom. Algae have always been present in the Venice lagoon but in combination with man made nutrients and warm end of summer water they started to develop in an abnormal way, making the ecosystem unstable.
In 1989, the Magistrato alle Acque of the Venice Council, which was the governmental body in charge of the problem, in cooperation with the Consorzio Venezia Nuova started to remove the algae to prevent the de-oxygenation of the Venice lagoon and the death of aquatic life.
The algae is difficult to dispose of, and the Magistrato alle Acque sought opportunities to use it in other ways. One option, co-sponsored by the European Union and involved in LIFE project, was to process it so that it could be added to paper as a way to substitute pulp and other materials, replacing these natural resources. In 1993, this led to the first sample of paper called "Alga Carta".
The raw algae are first dried and then milled in the paper mill to obtain seaweed ‘flour’. The flour is then combined with FSC fibres to make a high quality environmentally friendly paper. The outcome is a speckled paper where the speckles are the milled algae – over time, the paper becomes whiter due to the chlorophyll in the algae. Typically 5% to 10% of algae is used, but up to 30% is possible.
The manufacturing process of Shiro Alga Carta is patented by Favini.