LANDFILLING METHOD FOR REFURBISHING LANDSCAPES

Abstract

The present invention is directed to the use of a composite comprising a layer (L1) selected from the group of polyurethane layers, polyisocyanurat layers and polyurea layers as a landfill liner as well as a process for preparing a composite landfill liner comprising a layer (L1) selected from the group of polyurethane layers, polyisocyanurat layers and polyurea layers, the process comprising the step of applying a reaction mixture which is suitable to form a product selected from the group of polyurethane, polyisocyanurat and polyurea products onto a surface. Furthermore, the present invention is directed to a composite comprising a layer (L1) selected from the group of polyurethane layers, polyisocyanurat layers and polyurea layers, a primer layer on one surface of layer (L1), and a protective layer (L2) selected from the group of mortar layers or elastomer layers on the surface of the primer layer. In particular, the present invention is directed to the use of a composite comprising a polyurethane foam layer (L1) as a landfill liner, wherein the layer (L1) comprises a spray product as well as a preparing a composite landfill liner comprising a polyurethane foam layer (L1), the process comprising the step of applying a reaction mixture which is suitable to form a polyurethane foam onto a surface. Finally, the present invention is directed to a composite comprising a polyurethane foam layer (L1), a primer layer on one surface of layer (L1), and a protective layer (L2) selected from the group of mortar layers or elastomer layers on the surface of the primer layer.

Claims

1: A landfill liner, comprising a composite comprising a polyurethane foam layer (L1), wherein: the polyurethane foam layer (L1) comprises a spray product; and the spray product is a rigid or semirigid polyurethane spray foam.

2: The landfill liner of claim 1, wherein the polyurethane foam layer (L1) has a thickness in the range of 3 mm to 60 mm.

3: The landfill liner of claim 1, wherein the polyurethane foam layer (L1) has a density in the range of from 30 to 800 kg/m.sup.3.

4: The landfill liner of claim 1, wherein the composite further comprises a mesh or fibers.

5: A process for preparing a composite landfill liner comprising a polyurethane foam layer (L1), the process comprising: (i) applying a reaction mixture which is suitable to form a polyurethane foam onto a surface, such that the polyurethane foam layer (L1) is applied by spraying the reaction mixture onto a surface, and the polyurethane foam layer (L1) comprises a spray product which is a rigid or semirigid polyurethane spray foam; (ii) applying a primer on the surface of the polyurethane foam layer (L1) to obtain a layer (L1); and (iii) applying at least one protective layer (L2) selected from the group consisting of a mortar layer, an elastomer layer, and a mixture thereof.

6: The process according to claim 5, further comprising: (iv) applying at least one layer (L3) selected from the group consisting of a soil, a sand, a substrate suitable for plant growth, and mixtures thereof.

7: The landfill liner of claim 2, wherein the polyurethane foam layer (L1) has a density in the range of from 30 to 800 kg/m.sup.3.

8: The landfill liner of claim 2, wherein the composite further comprises a mesh or fibers.

9: The landfill liner of claim 3, wherein the composite further comprises a mesh or fibers.

10: The process according to claim 5, further comprising an additional step of applying a primer on the surface of the polyurethane foam layer (L1) to obtain a layer (L1).

Description

EXAMPLES

1. Materials:

[0165] 6 blocks of salt waste of 503020 cm, obtained from the Potash extraction site La Botjosa (Sallent). The surface is irregular and sharp but compact. The Salt blocks composition is mainly NaCl with clay spots. [0166] Elastospray 1602/5 Polyol and Lupranat M20S ISO are used in 100:100 in volume (Weight ratio 100:110) as a system with 100 kg/m.sup.3 density. The formulation is summarized below in table 1.

TABLE-US-00001 TABLE 1 formulation example Elastospray 1602/5 composition % Lupranol 3402 28 Lupranol 1200 20 Lupraphen 3905/1 17 Lupragen TCPP flame retardant 22 Triethanolamine 2 Glycerin 5 Polycat 9 catalyst 4 Silicone surfactant 1 Water 1 Orange Pigment 0.1

TABLE-US-00002 TABLE 2 Properties of the Polyol and Isocyanate Polyol properties Density 1120 Kg/m.sup.3 Hydroxyl value 370 mg/g Viscosity 500 mPas Isocyanate properties Density 1240 Kg/m.sup.3 NCO-content 31.5% Viscosity 210 mPas [0167] Mortar PUR developed solution: Foam-BASF 97088 Primer-BASF 97087 mortar [0168] Both materials are the result of a development with the most suitable selection of arids resins and water for the mortar (Portland cement based) and acrylic ester, charge materials (Latex) and water for the primer.

TABLE-US-00003 TABLE 3 Physical properties of 97087 mortar Property Unit value Norm general appearance grey powder density kg/m.sup.3 1310 50 UNE-EN 1097-3 dry components % 100 UNE-EN 12192-1 granulometry (% passes 1 mm sieve) consistency mm 195 10 EN 1015-3

TABLE-US-00004 TABLE 4 Physical properties of 97088 primer Property Unit Value appearance/color colorless liquid density g/cm.sup.3 aprox. 1.0 0.1 pH 7.5 1 dry residue % aprox. 40

2. Method:

[0169] The polyurethane foam is applied by means of a gun all around the block except from the base up to an average thickness of 1 cm all over the surface. [0170] The distance between the gun and the surface can vary, but it should preferably be around 40-80 cm. For larger areas, the foam will be sprayed in sections. When insulating a section, the product should be sprayed in a continuous way from left to right, or top to bottom, slowly advancing as the wave of the expanding foam grows behind the allied section. [0171] The spraying should be done in horizontal or vertical directions checking that there are no points with excessive product accumulation. Spraying should be as perpendicular as possible to the substrate. If the shape or height of the dump mountain makes it difficult to reach this distance or proceed in an adequate way, a crane and a long hose may be used to ensure quality foam spraying [0172] The same technique is used for the mortar primer and the mortar layer, applying from 50-100 gr/m.sup.2 for the primer by means of an airless gun and after 30 minutes up to 24 h applying the 5 to 10 kg/m.sup.2 mortar layer (5 mm) using a mortar spraying machine as Putzmeister MP25 which dries within a week.

[0173] Result: [0174] Covering: OK [0175] The irregular shape almost disappears by the foam. [0176] Adhesion: OK, PUR and Salt adhesion is excellent. Salt breaks before separating the foam from it. [0177] Consistence: OK, the layer is completely compact. [0178] Waterproofness: OK, the sample resists a 6 m water column. [0179] Material Compatibility with mortar: OK [0180] Mortar is completely joined to the foam

3. Physical Properties of the Product:

[0181] Foam samples were taken and looked the principal physical properties that were relevant for the application. Typical physical properties are summarized in table 1 [0182] Salt resistance behavior was tested using the long term water absorption test with saturated salt water bath comparing it to the original water bath both in aging conditions of 70 C. [0183] Conclusion: The foam offers excellent behavior for all the critical properties needed for the landfilling application.

TABLE-US-00005 TABLE 5 Elastospray 1602/5 Norm Density [Kg/m.sup.3] DIN EN 1602 100 Long term water absorption [% vol] DIN EN 12087 <2 Closed cell content [%] ISO 4590 >90 Salt resistance Ok Compression resistance [N/mm.sup.2] DIN EN 826 1.41