In February 2017, after five years of research and testing leading to final production, Thrace NG was awarded Greek Patent 1008913 for “Geosynthetic Reactive Clay (GRC) having an attapulgite clay core for the capping or containment of contaminated soil”.
George Arditzoglou, Civil Engineer / Technical Sales for Thrace NG, describes the idea behind this innovative GRC product, which was first conceived during the 15th European Conference on Soil Mechanics and Geotechnical Engineering that was held in September 12-15, 2011 in Athens, Greece and where Thrace NG was exhibiting:
“Instead of depositing a thick layer of the attapulgite clay in situ and between two geotextile layers, a notion of a new geocomposite product consisting of a thin layer of attapulgite clay sandwiched between a woven and a nonwoven geotextile was brought up. The attapulgite clay is unique in the sense that, due to the high surface area of its particles, it has the ability to react, attract and hold on to (adsorb) heavy metals without being fully saturated thus offering a long service life. As opposed to bentonite clay which swells when in contact with water and acts as water barrier, the attapulgite clay acts as a filter allowing water to flow. Due to the high cost of attapulgite clay and the cost of in situ installation, the development of a thin geocomposite attapulgite product provides a cost effective solution for applications where contaminated soil needs to be contained horizontally, or even vertically, something impossible with the traditional in situ deposit methods”.
The new GRC-attapulgite product was developed in collaboration with the inventors Dr. Anastasios Kollios, Civil Engineer and Dr. Vasileios Zotiadis, Geologist and Environmental Geochemist from the geotechnical company Edafomichaniki (Athens, Greece). Edafomichaniki conducted a comprehensive lab scale research on behalf of Thrace NG, aiming to study the physical, hydraulic and geochemical properties of commercial and laboratory produced attapulgite clay samples from various batches, obtained locally. Following the identification of the suitable attapulgite composition, Thrace NG proceeded with the final production of the GRC product.
Thrace NG GRC-attapulgite product is eligible for a European patent which is still pending.