CEMENTATION.

1. CEMENTATION. Lahoussoy thomas

2. CEMENTATION • It is a technique widely used for medium-level waste to long life. It is simple to implement, inexpensive and low binding as to the physical and chemical waste to integrate.

3. CEMENTATION • The cement has real capacity to chemical fixation of radioisotopes. In this sense, it differs from a simple matrix coating. When making cement, new compounds from chemical reactions between primary minerals made by the cement and waste constituents can form and effectively trapping radionuclides • Ce liant hydraulique est largement utilisé dans l’industrie nucléaire. Il sert à immobiliser des déchets solides au sein de conteneurs ou comme matrice de conditionnement pour enrober des déchets de moyenne activité.

4. CEMENTATION • ADVANTAGES lowcost easy installation • DRAWBACK The interactions between components of certain wastes and the cement matrix may lead to swelling and cracking of the package, reducing its durability.

5. NEW PROCESS • Studies have been conducted to optimize the cement while retaining its advantages in terms of cost and implementation. • Compostel • Sulfo-aluminous cements

6. COMPOSTEL • Method relies on the incorporation of radionuclides and soluble salts in a mineral structure and a hydraulic binder. His scientific feasibility has been demonstrated in laboratory scale. • However, the industrial implementation of this process is complex, which degrades the advantage of strong smooth implementation of the cementation.

7. COMPOSTEL • Stabilization of the waste Amalgamation of the radionuclides contained in the sludge soluble salts in a mineral structure of the family of sodium and zirconium phosphate (NZP) which is the function of containment • Immobilization of particles obtained in a cement matrix.

8. COMPOSTEL • Finally, the volume of waste conditioning is less than the initial volume of 10% to 50%, chemical durability properties acquired NZP phases are promising. • The industrial implementation of this process requires the design and develop a completely new facility, at least for the hydrothermal synthesis step, which can be complex.

9. SULFO-ALUMINOUS CEMENTS • Only the formulation of concrete changes, the facilities do not have to be modified.

10. SULFO-ALUMINOUS CEMENTS • Coatings by a common cement, calcium silicate type, is source of difficulty . • borates inhibit the binding decision. sulfates can cause swelling and delayed cracking of the hardened material. • It is often necessary to pretreat the waste for further limiting their interaction with the cement. What complicates the process and can increase the volume of waste to be packaged.

11. SULFO-ALUMINOUS CEMENTS • Sulfo-aluminous cements could be an attractive alternative to cement and calcium silicate. • By participating in the hydration reactions of the binder, borates and sulphates of the waste are incorporated in a non-expansive ettringite phase. • Exploratory laboratory tests were performed on a synthetic waste consisting of mud mixed with a chemical coprecipitation concentration evaporator

12. SULFO-ALUMINOUS CEMENTS • The use of a binder sulfo-aluminous partial replacement of cement is common source of significant progress, borates of waste did not block the binding decision of sulfo-aluminous, the waste can be cemented without prior pretreatment, which allows simplify the process and avoid the increase in volume due to the addition of reagents pretreatment.

13. CONCLUSION • These first promising results of sulfo aluminous cements can conclude that the scientific feasibility. • Compostel process, the use of sulfo-aluminous cement instead of ordinary cements leads to little or no modification of existing facilities cementation, this link is easy to implement.

14. THANK FOR YOUR ATTENTION