In order to achieve the utilization of the recycled aggregate scientifically and technologically, two The technology that is utilized in the specific project is based on the synthesis of inorganic polymers formed after mixing two components, a /solid precursor and an alkaline activating solution, resulting in a paste that can set and harden at room temperature. Under increased production conditions, the hardening can also take place under mild temperatures (<80oC). The specific objectives set for this projects are the following:
SO-1: To produce at least 10 m3 of geopolymers casted into paving blocks by the end of the project
SO-2: To produce materials with 3 different compressive strength ranges, between 5 and 50 MPa.
SO-3: To use the produced materials to cover an area of at least 100 m2, within the plant land-lot, for demonstration reasons
This material belongs to the compositional family of Me2O–MO–Al2O3–SiO2–H2O (where Me=Na, K,…and M=Ca, Mg,…). The materials to be developed are named geopolymers or inorganic polymers. Geopolymers is a new family of synthetic aluminosilicate materials formed by alkali activation of solid aluminosilicate raw materials. The geopolymerization reaction is exothermic and takes place at atmospheric pressure and temperatures below 100oC. Under a complicated mechanism, this reaction results in the formation of durable and compact amorphous to semi-crystalline solid materials characterized by a specific three-dimensional polymeric structure. Geopolymers possess excellent physicochemical, thermal and mechanical properties, like micro- or nano- porosity, high mechanical strength, notable surface hardness, thermal stability, fire and chemical resistance. Due to these properties, geopolymers are viewed as alternatives for construction materials with excellent mechanical and unique thermal properties.
There are two main scientific objectives in the DIAVAL project which are extremely innovative: a) the utilization of the diabase mud for the development of new geopolymers building materials; and b) the avoidance of mud pretreatment, and its use ‘as received’ from the plant, without drying, grinding or other kinds of preparation.
The building materials that will be developed will be paving/flooring blocks, which will be then delivered to the market. These slabs will come mainly from the diabase mud and will have better properties than the existing paving blocks and at same time reduce the environmental footprint of both the binder’s industry and the building industry. This is attributed to the following reasons:
- Geopolymer paving blocks have higher compressive strength than concrete (for the same mix proportion). This saves a lot of curing time and space at pre-casted block manufacturing units.
- Geopolymer paving blocks have superior resistance to chemical attack making them suitable for reactive soils;
- Geopolymer paving blocks outperform concrete paver blocks under freezing and thawing conditions. This makes them suitable for freezing environments where concrete based products deteriorate rapidly;
- Geopolymer paving blocks made out of waste materials have smaller CO2 and environmental footprint.
Apart from the above the following specific objectives have been set in the specific project:
- Evaluation of the products’ performance and properties (costs, technical performance, environmental quality) and comparison with traditional alternatives currently available in the market
SO-4: To elaborate an evaluation study to prove competitive advantages against substitute products.
- Preparation for commercialisation by verifying the business potential and customer needs for the developed products, and by creating ‘win-win’ cooperation with the construction industry.
SO-5: To elaborate a commercialisation plan for the 5 years after the end of this project