METHODS FOR OBTAINING AGGREGATES AND/OR POWDER-TYPE MINERAL MATERIAL UTILIZING PROCESS AUXILIARIES

Abstract

Methods of obtaining aggregates and/or pulverulent mineral material from a starting material comprising hardened mineral binder and aggregates utilizing process auxiliaries selected from the group consisting of polycarboxylate ethers and/or esters (PCE), glycols, organic amines, especially alkanolamines, ammonium salts of organic amines with carboxylic acids, surfactants, especially nonionic surfactants, gemini surfactants, calcium stearate, alkoxylated phosphonic or phosphoric esters, propane-1,3-diol, carboxylic acids, sulfonated amino alcohols, boric acid, salts of boric acid, borax, salts of phosphoric acid, gluconate, iron sulfate, tin sulfate, antimony salts, alkali metal salts, alkaline earth metal salts, lignosulfonates, glycerol, melamine, melamine sulfonates, water absorbents in the form of a superabsorbent polymer or in the form of a sheet silicate, anticaking agents, sugars, sugar acids, sugar alcohols, phosphates, phosphonates, and mixtures thereof.

Claims

1. A method of obtaining at least one of treated aggregates and treated pulverulent mineral material from a starting material comprising hardened mineral binder and aggregates by utilizing process auxiliaries to obtain the at least one of the treated aggregates and the treated pulverulent mineral material, the method comprising: a) treating the starting material in a disintegration operation in which the hardened mineral binder is at least partly carbonated and removed from the surface of the aggregates in the starting material so as to give a pulverulent disintegration product; and b) separating off the treated starting material at a predefined grain size limit in order to obtain the at least one of the treated aggregates having a grain size of at least the predefined grain size limit and the treated pulverulent mineral material having a grain size below the predefined grain size limit.

2. The method as claimed in claim 1, wherein the process auxiliaries are at least one selected from the group consisting of at least one of polycarboxylate ethers and esters (PCE), glycols, organic amines, ammonium salts of organic amines with carboxylic acids, surfactants, gemini surfactants, calcium stearate, alkoxylated phosphonic or phosphoric esters, propane-1,3-diol, carboxylic acids, sulfonated amino alcohols, boric acid, salts of boric acid, borax, salts of phosphoric acid, gluconate, iron sulfate, tin sulfate, antimony salts, alkali metal salts, alkaline earth metal salts, lignosulfonates, glycerol, melamine, melamine sulfonates, water absorbents in a form of a superabsorbent polymer or in a form of a sheet silicate, anticaking agents, sugars, sugar acids, sugar alcohols, phosphates, and phosphonates.

3. The method as claimed in claim 1, wherein the process auxiliaries comprise at least one alkanolamine selected from the group consisting of monoethanolamine, diethanolamine, triethanolamine (TEA), diethanolisopropanolamine (DEIPA), ethanoldiisopropanolamine (EDIPA), isopropanolamine, diisopropanolamine, triisopropanolamine (TIPA), N-methyldiisopropanolamine (MDIPA), N-methyldiethanolamine (MDEA), tetrahydroxyethylethylenediamine (THEED) and tetrahydroxyisopropylethylenediamine (THIPD), and salts of these alkanolamines.

4. The method as claimed in claim 1, wherein the process auxiliaries comprise at least one of glycols and glycerol, the glycols selected from the group consisting of monoethylene glycol, diethylene glycol, triethylene glycol, tetraethylene glycol, pentaethylene glycol, polyethylene glycol, neopentyl glycol, hexylene glycol, propylene glycol, dipropylene glycol, and polypropylene glycol.

5. The method as claimed in claim 1, wherein the process auxiliaries comprise at least one of at least one polycarboxylate ether and at least one polycarboxylate ester (PCE).

6. The method as claimed in claim 2, wherein the at least one PCE is a copolymer comprising: (i) repeat units A of general structure (I), ##STR00011## and (ii) repeat units B of general structure (II), ##STR00012## where each R.sup.u is independently hydrogen or a methyl group, each R.sup.v is independently hydrogen or COOM, where M is independently H, an alkali metal, or an alkaline earth metal, m=0, 1, 2 or 3, p=0 or 1, each R.sup.1 is independently —(CH.sub.2).sub.z—[YO].sub.n—R.sup.4 where Y is a C2- to C4-alkylene and R.sup.4 is a H, C1- to C20-alkyl, -cyclohexyl, -alkylaryl, or a —N(—R.sup.i).sub.j—[(CH.sub.2).sub.z—PO.sub.3M].sub.3-j, z=0, 1, 2, 3 or 4, n=2-350, j=0, 1 or 2, Ri is a hydrogen atom or an alkyl group having 1-4 carbon atoms, and M is a hydrogen atom, an alkali metal, an alkaline earth metal or an ammonium ion, wherein the repeat units A and B in the PCE have a molar ratio of A:B in the range of 10:90-90:10.

7. The method as claimed in claim 5, wherein, in addition to the at least one PCE, at least one further process auxiliary is used, and the at least one further process auxiliary is selected from the group consisting of glycols, alkanolamines, nonionic surfactants, lignosulfonates, glycerol, water absorbents in a form of a superabsorbent polymer or in a form of a sheet silicate, and anticaking agents.

8. The method as claimed in claim 1, wherein the process auxiliaries comprise at least one selected from the group consisting of sodium lignosulfonate, magnesium lignosulfonate, and calcium lignosulfonate.

9. The method as claimed in claim 1, wherein the process auxiliaries comprise a water absorbent, and the water absorbent is a superabsorbent polymer or sheet silicate.

10. The method as claimed in claim 1, wherein the process auxiliaries comprise a surfactant selected from the group consisting of fatty acid alkoxylates, alkoxylated alcohols, alkyl phenol alkoxylates, alkoxylated polycondensates, fatty acid amide alkoxylates, esters of fatty acids, sorbitan, glycerol or pentaerythritol, alkoxylated alkylamines having an alkyl radical consisting of 6-20 carbon atoms, alkylglycosides, alkylglucamides, alkoxylated sorbitans, lauryl ether sulfonates, naphthalenesulfonates, hydrophobized starches, hydrophobized celluloses, and siloxane-based nonionic surfactants.

11. A method of obtaining at least one of treated aggregates and treated pulverulent mineral material from a starting material comprising hardened mineral binder and aggregates, the method comprising: a) treating the starting material in a disintegration operation in which the hardened mineral binder is at partly carbonated and removed from the surface of the aggregates in the starting material so as to give a pulverulent disintegration product; and b) separating off the treated starting material at a predefined grain size limit in order to obtain at least one of the treated aggregates having a grain size of at least the predefined grain size limit and the treated pulverulent mineral material having a grain size below the predefined grain size limit, wherein at least one process auxiliary selected from the group consisting of at least one of polycarboxylate ethers and esters (PCE), glycols, organic amines, ammonium salts of organic amines with carboxylic acids, surfactants, gemini surfactants, calcium stearate, alkoxylated phosphonic or phosphoric esters, propane-1,3-diol, carboxylic acids, sulfonated amino alcohols, boric acid, salts of boric acid, borax, salts of phosphoric acid, gluconate, iron sulfate, tin sulfate, antimony salts, alkali metal salts, alkaline earth metal salts, lignosulfonates, glycerol, melamine, melamine sulfonates, water absorbents in a form of a superabsorbent polymer or in a form of a sheet silicate, anticaking agents, sugars, sugar acids, sugar alcohols, phosphates, and phosphonates, is added.

12. The method as claimed in claim 11, wherein the at least one process auxiliary is added to the starting material before the disintegration operation a).

13. The method as claimed in claim 11, wherein the at least one process auxiliary is added at least one of during the disintegration operation a) and during the separation b).

14. The method as claimed in claim 11, wherein a mixture of two or more process auxiliaries is added.

15. The method as claimed in claim 14, wherein the mixture of the two or more process auxiliaries is added in the form of a premix.

16. The method as claimed in claim 14, wherein the two or more process auxiliaries are added separately from one another.

17. The method as claimed in claim 11, wherein the carbonation is continued in step a) until a pH of the treated starting material in a range of 7-10 is attained.

18. A method for production of hydraulic compositions comprising utilizing the at least one of the treated aggregates and the treated pulverulent mineral material obtained in the method as claimed in claim 11 to produce the hydraulic compositions.

19. A mortar or concrete comprising at least one of the treated aggregates and the treated pulverulent mineral material obtained in the method as claimed in claim 11.

Description

EXAMPLES

[0262] Table 1 below gives an overview of the raw materials used in the examples.

TABLE-US-00001 TABLE 1 Raw materials used Binder A CEM I 42.5 R (Vigier) Binder B CEM II/A-LL (Vigier) PCE-1 Co(poly-acrylate-poly-methacrylate) with Mn = 5000 g/mol and methoxy-terminated polyethylene oxide side chains (Mn = 3000 g/mol); molar ratio of carboxylate:side chain = 4.5 PCE-2 Co(poly-acrylate-poly-methacrylate) with Mn = 5000 g/mol and methoxy-terminated polyethylene oxide side chains (Mn = 1000 g/mol); molar ratio of carboxylate:side chain = 0.8 PCE-3 Co(poly-acrylate-poly-methacrylate) with Mn = 5000 g/mol and methoxy-terminated polyethylene oxide side chains (Mn = 500 g/mol); molar ratio of carboxylate:side chain = 1.0 PCE-4 Copolymer of methallyl alcohol-started polyethylene oxide (Mn = 2400 g/mol), acrylic acid and 2-hydroxy acrylate in a molar ratio of 0.625:0.416:2.80 PCE-5 Copolymer of methallyl alcohol-started polyethylene oxide (Mn = 2400 g/mol) and acrylic acid in a molar ratio of 1:3.5 Sodium Sigma Aldrich (>99%) gluconate Molasses Untreated molasses from sugar production from cane sugar (solids content about 80% by weight; pH = 5.5) TIPA triisopropanolamine, Sigma-Aldrich (95%) MDIPA N-methyldiisopropanolamine, Eastman (>95%) SAP 1 Floset 27CC from SNF Floerger SAP 2 Postcrosslinked polyacrylate (BASF HySorb ® B6600) Hexylene 2-Methylpentane-2,4-diol, Sigma-Aldrich (99%) glycol Surfactant Isononanoic acid alkoxylated with 12 polyethylene oxide units

[0263] In a first variant, pulverulent mineral material according to the present invention was produced in a dry method. For this purpose, fully hydrated CEM I cement was ground in a pinned disk mill under a CO.sub.2 atmosphere (5% by volume of CO.sub.2) to a particle size of 0-250 μm. This powder is designated Powder 1.

[0264] In a second variant, pulverulent mineral material according to the present invention was produced in a wet method. This method was identical to the method described in WO2014154741 (page 18 lines 2-29). This powder is designated Powder 2.

[0265] Composite binders were produced by mixing Powder 1/Powder 2 with CEM I 42.5 R cement in a tumbling mixer until there was a visually homogeneous powder. The composite binders were designated Binder C-E and had the following composition:

TABLE-US-00002 TABLE 2 Composition of the composite binders Binder C Mixture of CEM I 42.5 R and Powder 1 (weight ratio 82:18) Binder D Mixture of CEM I 42.5 R and Powder 1 (weight ratio 65:35) Binder E Mixture of CEM I 42.5 R and Powder 2 (weight ratio 88:12)

[0266] Slump was ascertained in accordance with EN 1015-3 with a cone of volume 39 cm.sup.a at various times after the end of the mixing operation. Slump of <60 mm was not measured and was reported in each case as “<60”.

[0267] The commencement of solidification was determined from an isothermal calorimetry method in accordance with ASTM C1702-17. For this purpose, the exothermicity of hydration was recorded using a CAL 8000 instrument from Calumetrix. The commencement of solidification corresponds to that point on the exothermicity curve against time at which a first local minimum was measured.

[0268] Compressive strengths and flexural tensile strengths were measured according to standard EN 196-1.

Example 1

[0269] Example 1 illustrates the efficacy of various process auxiliaries in a method of the invention. The types and amounts of process auxiliaries specified in tables 3 and 4 were each added before commencement of the disintegration operation in the production of Powder 1. The pulverulent mineral material obtained, with or without process auxiliary, was tested as part of a composite binder in mortar mixtures. For this purpose, 450 g of the binder specified in tables 2 and 3 was mixed with 1350 g of sand (CEN 0-2 mm standard sand) and 225 g of water. Examples 1-4 to 1-10 and 1-12 to 1-14 are inventive, whereas examples 1-1, 1-2, 1-3 and 1-11 are noninventive comparative examples.

TABLE-US-00003 TABLE 3 Examples 1-1 to 1-14 1-1 1-2 1-3 1-4 1-5 1-6 1-7 Binder A B C C C C C Process auxiliary 0.1* 0.1* 0.1* 0.1* PCE-5 PCE-4 PCE-3 PCE-2 Slump 190 188 184 201 194 202 206 3 min [mm] Compressive 13.6 10 9 10.8 10.5 9.9 9.4 strength 1 d [MPa] Compressive 23.8 18.4 17.4 20.1 19.3 19.8 17.7 strength 2 d [MPa] Compressive 48.9 37.9 35.2 36 37.6 38.3 37.5 strength 28 d [MPa] Flexural tensile 3.1 2.8 2.5 2.8 2.9 2.5 2.7 strength 1 d [MPa] Flexural tensile 4.6 4.3 4.1 4.4 4.5 4.1 4.1 strength 2 d [MPa] Flexural tensile 7.1 6.2 5.7 5.7 6.3 6.0 6.6 strength 28 d [MPa] 1-8 1-9 1-10 1-11 1-12 1-13 1-14 Binder C C C D D D D Process auxiliary 0.17* 0.1* 0.08* 0.1* 0.1* 0.1* PCE-1 sodium molasses PCE-4 PCE-2 sodium gluconate gluconate Slump 200 n.m. 197 170 204 203 195 3 min [mm] Compressive 11 11.3 7.3 6 6.8 6.8 6.5 strength 1 d [MPa] Compressive 19.7 21.8 18.7 12.9 14.8 14.9 15.2 strength 2 d [MPa] Compressive 38.1 41 38.2 26.6 30.6 29.7 31 strength 28 d [MPa] Flexural tensile 3 2.9 2.1 1.6 1.8 1.9 1.8 strength 1 d [MPa] Flexural tensile 4.2 4.8 3.9 3.1 3.1 3.4 3.4 strength 1 d [MPa] Flexural tensile 6.1 6.7 6.1 4.6 5.5 4.8 5.7 strength 1 d [MPa] *Dosage in % by weight based on the proportion of Powder 1

[0270] For the examples in table 4, combinations of 2 process auxiliaries were used. All examples 1-19 to 1-21 are inventive examples.

TABLE-US-00004 TABLE 4 Examples 1-19 to 1-21 1-19 1-20 1-21 Binder C C D Process auxiliary 1 0.05* PCE-4 0.05* PCE-2 0.1* PCE-2 Process auxiliary 2 165** TIPA 200** MDIPA 165** TIPA Slump 3 min [mm] 200 195 not measured Compressive strength 1 d 11 11.1 11.5 [MPa] Compressive strength 2 d 22.2 19.2 21.6 [MPa] Compressive strength 28 d 43.6 [MPa] Flexural tensile strength 3.2 2.9 3 1 d [MPa] Flexural tensile strength 4.6 4.1 4.3 1 d [MPa] Flexural tensile strength 6.9 1 d [MPa] *Dosage in % by weight based on the proportion of Powder 1 **Dosage in ppm based on the binder

[0271] As apparent from tables 3 and 4, process auxiliaries of the invention improve slump and strengths in general. This is true in a comparison of the mortar samples comprising binder comprising pulverulent mineral material and process auxiliary according to the present invention with mortar samples comprising the same binder but no process auxiliaries (cf. examples 1-4 to 1-10 with example 1-3, and examples 1-12 to 1-14 with example 1-11). The use of a combination of PCE and alkanolamine leads to a further improvement compared to use of PCE alone (see table 4). Finally, it is remarkable that the use of process auxiliaries of the invention has the effect that a cement containing 18% by weight of a pulverulent mineral material from a method of the invention has essentially the same or improved strengths compared to a standardized CEM II/A-LL (compare example 1-2 with the inventive examples).

Example 2

[0272] Example 2 illustrates the efficacy of process auxiliaries of the invention for prevention of the tendency of the starting material to cake, especially demolition rubble or building waste for a method according to the present invention. A low tendency of the starting material to cake is important in a method of the invention since carbonation and disintegration otherwise cannot proceed efficiently.

[0273] Tendency to caking was tested in a method in accordance with standard EN 1097-6. This involves assessing the stability of a compacted concrete/sand cone. In the example, coarse concrete sand (0-4 mm, water demand according to EN 1097-6 of 10.5% by weight) was first dried at 110° C. and then wetted with water in the amount specified in table 5. The stability of such a sample was then tested according to EN 1097-6 by assessing the tendency of a concrete/sand cone to collapse. In addition, samples of the same water-wetted coarse concrete sand were admixed with the process auxiliaries specified in table 5 in the amount specified therein. The stability of these samples too was tested to EN 1097-6. In the case of success, the firm concrete sand (corresponding to image F.1 in EN 1097-6) gives rise to a free-flowing bulk material, indicated by almost complete collapse of the concrete/sand cone, but in which a clear peak can still be seen (corresponding to image F.3 of EN 1097-6). However, excessive drying should be avoided (corresponding to image F.4 of EN 1097-6).

TABLE-US-00005 TABLE 5 Examples 2-1 to 2-9 2-1 2-2 2-3 2-4 2-5 Added water [% by wt. 13.1 13.1 13.1 16.3 16.3 based on concrete sand] Process auxiliary [% by  0.2  0.3  0.4  0.3  0.3 wt. based on concrete SAP-1 SAP-1 SAP-1 SAP-1 SAP-1 sand] Assessment of F.1 F.3 F.4 F.1 F.3 concrete/sand cone firm free- dry firm free- according to flowing flowing EN 1097-6 2-6 2-7 2-8 2-9 Added water [% by wt. 16.3  16.3  11 11.4 based on concrete sand] Process auxiliary [% 0.6 0.8    0.15  0.1 by wt. based on concrete SAP-2 SAP-2 Hexylene Surfactant sand] glycol Assessment of F.1 F.3 F.3 F.3 concrete/sand cone firm free- free- free- according to EN 1097-6 flowing flowing flowing

[0274] As apparent from table 5, addition of a suitable amount of process auxiliary can give a free-flowing mixture. In other words, the caking tendency of a starting material can be reduced, which constitutes a great advantage with regard to the implementability of a method of the invention.

Example 3

[0275] Example 3 illustrates the efficacy of process auxiliaries in a wet method. The types and amounts of process auxiliaries specified in table 6 were each added before commencement of the disintegration operation in the production of Powder 2. The pulverulent mineral material obtained, with or without process auxiliary, was tested as part of a composite binder in cement suspensions. For this purpose, the respective binder was mixed with water in a weight ratio of binder to water of 0.4. Examples 3-3 to 3-5 are inventive, whereas examples 3-1 and 3-2 are noninventive comparative examples.

[0276] The commencement of solidification was determined in a heat flow curve that was measured in an isothermal process in accordance with standard ASTM C1702-17. An i-CAL 8000 instrument from Calmetrix was used. The commencement of solidification is the time at which a first local minimum of the heat flow against time was attained.

TABLE-US-00006 TABLE 6 Examples 3-1 to 3-5 3-1 3-2 3-3 3-4 3-5 Binder B E E E E Process auxiliary 2.5* 3.3* 5* PCE-5 PCE-5 PCE-5 Slump 3 min [mm] 103 58 81 106 185 Commencement of 96 72 102 120 120 solidification [min] *Dosage in % by weight based on the proportion of Powder 2

[0277] It is found that use of process auxiliaries of the invention in a wet method can distinctly improve the flowability of resulting cements.