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We are used to considering beached algae as waste ... or worse, as garbage! Is it possible to turn them into a precious resource? The case of Grado (Italy).

image credit: Foto by Marco Colmari: Grado Pineta (Italy)
Marco Colmari's picture
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  • Feb 28, 2022
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I have been frequenting the beach of Grado for many years, in particular the coastal strip of the Pineta.

Here the presence of beached algae... opppsss, sorry... beached phanerogams (this is their real name!), has always represented a big obstacle for the Municipal Administration.

We tourists and swimmers automatically associate algae with a state of neglect, dirt and lack of decorum.

Our judgment, however, is somewhat superficial. We must realize that the grasslands of Cymodocea nodosa (the main phanerogam of Grado), which grow not far from the shore, are of fundamental importance!

They are indispensable for the life of the sea itself, produce oxygen through photosynthesis, create the ideal environment for numerous marine species, represent the "nursery" of many fish and prevent coastal erosion.

Therefore, before throwing ourselves into hasty judgments, we must keep in mind that the importance of these "annoying algae" for the marine world is comparable to that of the Amazon rainforest for the terrestrial world.

 

But back to the Grado problem...

The deposits of algae present on the beach are in fact not very compatible with the needs of bathers. This is a fact! So how can this problem be solved?

Well ... until 2015 the Municipal Administration tried to make the beaches more usable by entrusting external companies with the task of collecting the deposits of "algae" and other materials on the beach, for subsequent transport to landfills.

It is, to clarify our ideas, of something like 6000-8000 tons of material (algae, sand, wood, waste of all kinds, etc ...) disposed of in landfills every summer!

Cost of the operation? From 300000 to 500000 euros per season! A cost entirely borne by the Community!

 

What happened in Grado in 2015?

An important decision was made in 2015. On the basis of some directives and guidelines issued by the European Community (sometimes even Europe does something useful!), The Municipality of Grado has decided to change course.

Along the beach some containment structures were built for algae and collected material. These are simple fences, visible to all and characterized by the use of a dense net on which the now famous writing stands (famous for those who frequent the beaches of Grado): "Do not call us algae ... we are phanerogams".

Yes ... I agree with you ... these fences do not look good, and in addition they can become a source of bad smells and a receptacle for flies, various insects and rats!

Well ... despite all the doubts ... you must know that the project also includes the use of enzymatic products to counteract the formation of bad smells, bait traps against rats and maintenance of a maximum accumulation limit equal to 1.5 meters (will it be true?).

 

The purpose of the collection areas

How are these storage fences used? Inside them a first rough sieving takes place, in order to separate the "algae" from the wood and any other type of material. At the end of the season the algae, or rather the marine phanerogams, are redistributed along the beach, in order to form a natural breakwater and counteract the erosion of the beach due to storm surges.

The rest of the material, as well as the surplus, is transported to a structure dedicated to waste management:

This structure, for those unfamiliar with Grado, is located on the island "Le Cove", near the Cemetery. Here the final separation of algae from all other materials takes place. After an initial drying and screening phase, the sand and shells inevitably collected together with the algae are separated: this sand is reused for normal nourishment and leveling operations, to counteract natural erosive phenomena. Through other mechanical screening operations, all other unwanted materials are isolated: plastic, glass, etc...

What remains at the end of the process is the only plant biomass.

 

What to do with plant biomass?

Currently the Municipality of Grado, similarly to what happens in many other Italian seaside resorts, sends the vegetable biomass to some composting plants, that is for the production of the famous “fertilizing soil”.

But this is not the only conceivable use for algae, because several solutions are possible:

  1. Production of compost and fertilizers for agricultural use
  2. Production of insulating materials for building (interesting, from this point of view, the use of posidonia "spheres" in Sardinia)
  3. Paper production (in Italy the so-called "Beachcomber" of the Favini paper industry is now famous)
  4. Transformation into renewable fuels such as "pellets"

The desirable solution

Through the project launched in 2015 it was possible to significantly reduce the costs of disposal of algae deposits and various materials on the beaches of Grado. This is a first result, already commendable in itself. To date, the municipal administration has commissioned a German company for an eventual project for the reuse of algae, through a processing plant to be built in the same municipal area. I hope that this wonderful initiative will end in a short time: that of transforming waste into a precious resource!

It would be a source of pride for Grado, as well as an example to imitate for all seaside resorts… in Italy and in the world!

 

Please note. Source of some images: web

 

Marco Colmari - Tekno Training

 

Discussions
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Matt Chester's picture
Matt Chester on Feb 28, 2022
  1. Transformation into renewable fuels such as "pellets"

What's the expected cost of this fuel vs. comparable biofuels produced elsewhere? 

Marco Colmari's picture
Marco Colmari on Feb 28, 2022

This is an interesting question but at the moment I am unable to answer you.... sorry.

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