Three Greek companies have heeded a call to protect a marine environment damaged by pollution, joining in an environmentally friendly effort to keep the Mediterranean healthy. Athena-Hellenic Engineering Industrial and Touristic Co. S.A., Technical Company Christopher D. Constantinidis S.A., two of Greece's largest construction companies, and Almyra S.A., a committed poison-free, solvent-free antifouling producer, are providing Thessaloniki with a system to deliver treated water to a clean sea.
For years Thessaloniki has needed a larger sewage treatment plant. The existing plant treats only half of the city's sewage, with the balance pumped directly from local neighborhoods, solids and all, into the sea. This deposits large amounts of untreated matter, with its attendant health hazards and bacteria, directly into water used nearby for swimming and fishing. An over-taxed sea cannot cleanse itself. With Thessaloniki's growing population, the sea's ability to cope with half the area's untreated sewage was in jeopardy.
In a move to help Thessaloniki and the environment, the European Union supplied 85 percent of the funds, and Technical Company Christopher D. Constantinidis S.A., which had designed and built the first stage of the existing plant, entered into a joint venture agreement with Athena-Hellenic Engineering Industrial and Touristic Co. S.A. The two companies were selected to design and construct the new outflow section of the project, enabling the city to treat 100 percent of its sewage by the end of the year 2000. (Aktor-Themeliodomi company was selected to extend the treatment plant itself.)
According to H. Papantoniou of Athena-Hellenic-Constantinidis, in order to spread delivery of the treated water, the design includes two effluent transfer pipes running side by side underground for 7.5 kilometers from the treatment station, then underwater, separating into a "Y" about 900 meters from shore, continuing into the sea for a total of 2.5 kilometers. Toward the end, diffusers - smaller pipes running off the two main pipes - further dissipate treated water, allowing water currents a greater ability to disperse it further out to sea.
One of the major engineering problems during the design stage of underwater projects is how to counteract the harmful effects of marine growth. In normal use, when a pumping station's outflow is low, seawater washes back inside these pipes, sometimes to the shoreline, filling them with seawater and giving marine growth - fouling - an opportunity to proliferate on the interior. Marine growth is a major problem worldwide. Tubeworms, mussels, barnacles, sea grass and other marine matter are all living organisms that connect to any surface making its home in salty or fresh waters, causing innumerable problems.
On the inside of an unprotected wastewater pipe, in this case with a diameter of 1,600 mm, potential marine fouling damage is astounding. Within a few years, it can grow to as much as 300 kilos per square meter and be up to 20 cm thick, reducing water flow to a trickle over time and eventually closing the pipe completely.
Outside, the stationary concrete pipes present a different problem. They can handle heavy weights, but must be protected with a reinforcing, strengthening coating to counteract the damaging effects of salt water and marine borers. Unfortunately, the original design included a poisonous antifouling paint inside and tar epoxy outside, a material forbidden for use in most of the world's seas.
Designers at Athena-Hellenic-Constantinidis understood the incongruity of treating wastewater, yet using poison-based materials on effluent pipes, leeching poison directly into both treated water and the sea around the total five kilometers of underwater piping, but they knew no effective alternatives.
Enter Kjell Alm of Almyra S.A., a Swedish inventor who has made Greece his home for more than seven years. He has two better ideas, both environmentally friendly, both non-toxic, using 100 percent poison- and solvent-free materials that produce no hazardous waste.
The first, SealCoat, is a velvety fiber and epoxy antifouling system. Its surface in water replicates the movement of a seal's fur (hence the name): Like a seal at rest [the condition of a stationary pipe, the fibers open and close with light water movement. With rapid movement, as in the flow of treated water on its may to the sea, or seawater flowing back in, the fibers slick back, washing off any marine growth trying to get a foothold, and are mechanically self-cleaning, a design feature of the product.
SealCoat has been thoroughly tested in Greek waters, and is in use here and elsewhere on sailboat, powerboat and tugboat bottoms; on oil rig platforms and tankers in China and under "laboratory conditions" in various marinas.
The exterior will be coated with SealCoat TC, an extremely flexible food-grade tank coating Alm has created, in use on the interiors of storage tanks, such as wine, soya cooking oil, and beverages, as well as petroleum and similar products. It also uses fibers, but in this case they are embedded inside two layers of a slightly different epoxy, further increasing its elasticity, protecting the concrete and the sea around it, for it, too, is non-toxic.
Why the need for antifoulings?
Stationary objects have great problems with fouling in water. There is damage from water erosion as well as from marine growth. In a famous incident in 1982 in Norway that focused attention on the problem, one leg of the Alexander Kelland oil platform collapsed due to heavy marine growth, which, as noted, can be as much as 300 kilos per square meter. An all-steel construction, it had traditional poison paint antifouling on it.
Several years after its construction, when the antifouling was no longer viable, marine growth attached itself in earnest. Water movement patterns cause irregular growth, and one leg became particularly heavy. The unbalanced weight ruptured it, demolished the platform, caused great damage from the oil spill that resulted, and all the people who were on it died. Now divers regularly hard- scrape and clean platform legs. (SealCoating cuts down on cleaning costs, as marine growth and slime is minimal and divers simply brush it off.)
In the Great Lakes in the U.S., where the Zebra mussel problem is endemic, buoys and boats anchored in place for long periods have been known to sink under the weight of rapidly-building growth. Movable objects like boats present additional problems: they will get heavier, the hull expanse slightly greater as it thickens with fouling. It will move more slowly in the water, and fuel costs will increase tremendously over time. The more fouling there is, the more expensive is the cost of running the boat.
The accidental invention of an underwater wonder
Fibers are used world-wide on various surfaces (Alm's product, with a slightly different epoxy base, is currently inside Volvo automobiles in a total of 54 places, for "buss, bubble and squeak" - those annoying squeaks and rattles that are often part of a car's interior soundscape - and for protecting the interior of door panels and other parts from rust and corrosion. In 1992, Alm discovered the technology for SealCoat entirely by accident, on his way to testing something else. Studying the use of fibers applied to surfaces, he did friction tests on ball bearings. After successful testing, he wanted to do further comparisons, and a boat moving through water was an obvious choice. Taking two identical boats, he painted one with an environmentally friendly antifouling bottom paint, and the other with his special epoxy-and- fiber system. The friction tests proved his thesis correct, and, over the next winter he continued testing his fiber-friction hypothesis on various other surfaces.
But a funny thing was happening underwater on the surface of the fiber-coated boat, something he was not expecting that changed the course of his tests - and his life.
Nothing was growing.
Both boats, as usual, remained in the water during the winter months. In spring, when they were removed for normal bottom cleaning, the traditionally antifouled boat was covered with marine growth. The velvety surface of the fiber-coated boat had none. Knowing he had something, but not knowing exactly what, or even how he got there, Alm immediately internationally patented the fiber-and-epoxy system as an antifouling agent. Years of testing followed, from Sweden to China, Florida to Boston, and in Greece and Denmark, among other places, utilizing laboratories in universities and large chemical companies. Placing test surfaces in dissimilar waters, he tried various application procedures and fiber lengths and types until he was certain he had a successful product.
Then in 1998 he introduced the product on the world shipping market at the Posidonos Fair in Piraeus.
Eliminating the poisons in our seas is good for everyone
Until now there were no poison-free alternatives that worked, and the law did not require change. Both elements are changing. Recording to Alm, keeping ship hulls and stationary objects in water clean is a billion-dollar business worldwide, with a large portion in Greece. (Forty percent of the world market for commercial vessels is here.) Currently the majority are treated with poison- and solvent-based "bottom paints" that deter, slough off or kill marine growth. Although they are cheaper, they are as much a problem for the world's seas as the marine growth they attempt to control, slowly leeching poison into the sea and killing off seafood, possibly even moving up the food chain.
Despite the use of poison bottom paints, marine growth continues. Removing it is tedious, expensive work requiring hauling the boat out of the water yearly or twice-yearly, or sending divers down to hard-scrape stationary objects. While it is in dry-dock, a boat is not making money or providing pleasure. In addition, there is the cost and time involved in scraping off rock-hard growth, then sanding and repainting the underwater area up to the water line with paints that have been, until recently, poisonous: toxic to the creatures who attach themselves, the waters those boats lie in or travel through, as well as to the people who remove the old antifouling - now hazardous waste - and apply the new. In Korea a workers union investigated health problems caused by the use of poisonous and solvent-based paints. Workers involved with this type of paint for more than five years have major health problems. It is estimated that 20-25 percent are suffering from some form of cancer, and 90-95 percent have alcoholic problems.
"Imagine," said Alm, in an interview with Kathimerini's English edition, "in some places in the world you cannot wash your car in your driveway or the street because of the oils and chemicals that wash off and run into groundwater, yet what me have allowed around our workers and put into our seas is a different story. Poisons not only have been allowed, but are purposefully used as part of marine growth management. At last this is changing."
And Alm is part of the change by providing a truly effective product that deters marine growth, yet is poison free, environmentally friendly, mechanically self-cleans, and is guaranteed for three to five years depending on use and application.
Poisonous paint products, such as biocides, and heavy metals like copper are being outlawed and taken off the world market over the next several years. Lead-based paints are already totally outlawed - although, according to boatyard workers, they can be found on ship chandlers' shelves in Piraeus, along with poisons like arsenic, still being mixed - illegally - into bottom paints here.