(19)
(11)EP 3 058 118 B1

(12)EUROPEAN PATENT SPECIFICATION

(45)Mention of the grant of the patent:
29.04.2020 Bulletin 2020/18

(21)Application number: 14793360.0

(22)Date of filing:  09.10.2014
(51)International Patent Classification (IPC): 
C22B 3/02(2006.01)
C23F 14/02(2006.01)
(86)International application number:
PCT/US2014/059890
(87)International publication number:
WO 2015/057489 (23.04.2015 Gazette  2015/16)

(54)

GYPSUM SCALE INHIBITORS FOR ORE SLURRY SYSTEMS IN HYDRO METALLURGICAL APPLICATIONS

GIPSKESSELSTEINHEMMER FÜR ERZSCHLAMMSYSTEME BEI HYDROMETALLURGISCHEN ANWENDUNGEN

INHIBITEURS DE DÉPÔT DE GYPSE POUR SYSTÈMES UTILISANT DE LA PULPE DE MINERAI DANS DES APPLICATIONS HYDROMÉTALLURGIQUES


(84)Designated Contracting States:
AL AT BE BG CH CY CZ DE DK EE ES FI FR GB GR HR HU IE IS IT LI LT LU LV MC MK MT NL NO PL PT RO RS SE SI SK SM TR

(30)Priority: 15.10.2013 US 201361890998 P

(43)Date of publication of application:
24.08.2016 Bulletin 2016/34

(73)Proprietor: Solenis Technologies, L.P.
8200 Schaffhausen (CH)

(72)Inventors:
  • BAKEEV, Kirill N.
    Newark, DE 19702 (US)
  • DIMAIO, Andrew M.
    Oxford, PA 19363 (US)

(74)Representative: LKGlobal UK Ltd. 
Cambridge House, Henry Street
Bath BA1 1BT
Bath BA1 1BT (GB)


(56)References cited: : 
WO-A1-2013/019627
US-A- 5 454 954
US-A- 5 368 830
US-A1- 2013 090 425
  
  • HE SHILIANG ET AL: "Inhibition of mineral scale precipitation by polymers", WATER SOLUBLE POLYMERS: SOLUTION PROPERTIES AND APPLICATIONS, [PROCEEDINGS OF A SYMPOSIUM ON WATER SOLUBLE POLYMERS: SOLUTION PROPERTIES AND APPLICATIONS], LAS VEGAS, SEPTEMBER 7-11, 1997,, 1 January 1998 (1998-01-01), pages 163-171, XP009182327, ISBN: 0-306-45931-0
  • AMJAD ET AL: "Gypsum scale formation on heat exchanger surfaces: the influence of poly(acrylic acid), poly(aspartic acid), and poly(glutamic acid)", ACTA POLYTECHNICA SCANDINAVICA. CH, CHEMICAL TECHNOLOGY ANDMETALLURGY SERIES, FINNISH ACADEMY OF TECHNICAL SCIENCES, HELSINKI, FI, vol. 244, 1 January 1997 (1997-01-01), pages 56-58, XP009182320, ISSN: 0781-2698
  • WEIJNEN M P C ET AL: "Adsorption of phosphonates on gypsum crystals", JOURNAL OF CRYSTAL GROWTH, ELSEVIER, AMSTERDAM, NL, vol. 79, no. 1-3, 2 December 1986 (1986-12-02), pages 157-168, XP023327512, ISSN: 0022-0248, DOI: 10.1016/0022-0248(86)90431-8 [retrieved on 1986-12-02]
  
Note: Within nine months from the publication of the mention of the grant of the European patent, any person may give notice to the European Patent Office of opposition to the European patent granted. Notice of opposition shall be filed in a written reasoned statement. It shall not be deemed to have been filed until the opposition fee has been paid. (Art. 99(1) European Patent Convention).


Description

BACKGROUND OF THE INVENTION



[0001] The invention relates to methods for inhibiting scale in relatively high solids content environments in industrial mining operations. The compositions comprise an active selected from carboxylate polymers and polyamino acids.

[0002] The mineral industry is a large consumer of chemicals which are used during many stages of the processing of the mineral ore. For example, chemicals are added to inhibit the development of various types of scale which can develop in different stages of ore processing. Different conditions during different unit operations of ore processing systems require different chemicals to inhibit the scale.

[0003] The processing of mineral ore is very complex with maintenance required to maintain throughput throughout the process, with maintenance downtime kept to a minimum, thus allowing for more ore to be processed at less cost Unit operations within an industrial mining process involving the formation and/or cooling of mineral ore slurries need constant monitoring, cleaning and maintenance of equipment Examples of such equipment include quench tanks and autoclaves, as well as ancillary lines and equipment. Quench tanks and autoclaves, as well as ancillary lines and equipment, are subject to scaling which if not prevented requires stopping the mining operation and physically removing the scale.

[0004] The mining industry is constantly seeking new additive technologies that will increase the efficiency of ore processing during various stages, thus enhancing the overall ore recovery in mineral processing operations. Chemicals, and chemical combinations, have been shown to inhibit scale in aqueous solutions.

[0005] However, the conditions of the ore change dramatically throughout the processing and the mineral ore in the cooling stages of a quench tank or autoclave operation can have high solids content, i.e. in the form of slurry and are not 100% aqueous. New chemicals must be found to enhance mineral ore processing when in the slurry phase. Further, due to increased environmental concerns over mining operations, chemical anti-sealant additives comprising natural materials that provide decreased environmental harm are desired.

[0006] US 5 454 954; WO 2013/019627 A1; He et al., Water Soluble Polymers, 1998, 163-171; Amjad, Acta Polytechnica Scandinavica, 244, 1997, 56-58; and US 2013/0090425 A1 disclose processes for inhibiting scale.

[0007] All parts and percentages set forth herein are on a weight-by weight basis unless otherwise indicated.

SUMMARY OF THE INVENTION



[0008] The compositions useful as anti-sealant controls in mining operations in the aqueous slurry phase comprise an active component selected from the group consisting of carboxylate polymers and polyamino acids. The anti-sealant compositions are typically added to mineral slurry in the mining operation in an amount effective to inhibit the formation of scale in pipes and equipment used for ore recovery, for example with respect to a quench tank or autoclave the composition can be added to the slurry in the quench tank or autoclave, and/or in an ancillary line or piece of equipment. Thus, the invention encompasses a mineral ore slurry comprising an aqueous phase having a mineral ore and a anti-sealant composition comprising an active component selected from the group consisting of carboxylate polymers and polyamino acids in an amount effective to inhibit scale on the metal, polymer, plastic or ceramic surfaces of the quench tank or autoclave, and/or ancillary line or equipment.

[0009] Generally, application of the anti-sealant increases the capacity and throughput of mineral ores in the mining process by inhibiting the build-up of complex scale, in particular gypsum scale, in the interior walls and devices of the equipment and piping. This will benefit operations by decreasing downtime and cost associated with it due to cleaning and maintenance and also helps create a more efficient system by moving more ore slurry through the cooling process in shorter time periods. In addition, the use of the anti-sealant also reduces health and safety risks associated with high frequency quench circuit mechanical de-scaling and increases quench tank circuit equipment life time.

DESCRIPTION OF THE DRAWINGS



[0010] 

Fig. 1 shows a typical mineral ore quenching operation in an embodiment of the invention.

Fig. 2 shows typical mineral ore quenching operation comprising preliminary quench devices in an embodiment of the invention.

Fig. 3 shows a typical mineral ore autoclave operation in an embodiment of the invention.


DETAILED DESCRIPTION OF THE INVENTION



[0011] The active component of the anti-sealant composition can be selected from carboxylate polymers having the formula

        R1-CH2-CH(CO2H)-R2-R3

wherein R1 is selected from a functional group, R2 is a polycarboxylate and R3 is hydrogen or a functional group. In embodiments, the functional groups of R1 and R3 comprise sulfonate, sulfate, phosphinate, phosphonate, alcohol, 1,1-diphenyl hexyl, tert-butyl, mercaptoethanol, mercaptopropionic acid, mercaptoglycolic acid and R2 comprises a polyacrylic acid. Typically, the carboxylate polymers will have a molecular weight between about 1,000 g/mol to about 20,000 g/mol, such as between about 2,000 g/mol to about 12,000 g/mol. In an embodiment, the carboxylate polymer comprises polyacrylic acid.

[0012] In one aspect, the active component of the anti-sealant composition can be selected from polyamine acids having the formula

        poly(X)mpoly(Y)n,

wherein X and Y are independently selected from the group consisting of an amino acid, a salt of an amino acid and an amino acid derivative, and m can be from about 2 to about 60, n can be up to about 60, and the sum of m and n is at least about 5. For example, X and Y may be independently selected from the group consisting of aspartic acid, glutamic acid, lysine, aspartate, glutamate, a salt of lysine, an aspartate derivative, a glutamate derivative, and a lysine derivative; m can be from about 5 to about 12; n can up to about 12 and the sum of m and n can be from about 5 to about 12. In one aspect the polyamine acid can comprise polyaspartic acid.

[0013] The anti-sealant composition is useful to control complex scale, such as gypsum scale, in mining operations. Typically, the process comprises the steps of adding to the aqueous mineral ore slurry having an aqueous phase an effective scale inhibiting amount of a scale inhibiting composition comprising an active component selected from the group consisting of i) a carboxylate polymer having the formula

        R1-CH2-CH(CO2H)-R2-R3

wherein R1 is selected from the group consisting of sulfonate, sulfate, phosphinate, phosphonate, alcohol, 1,1-diphenyl hexyl, tert-butyl, mercaptoethanol, mercaptopropionic acid, mercaptoglycolic acid, R2 is i) a polycarboxylate, and R3 is H or R1; and ii) a polyamine acid having the formula: poly(X)mpoly(Y)n, wherein X and Y are independently selected from the group consisting of an amino acid, a salt of an amino acid and an amino acid derivative, and m can be from about 2 to about 60, n can be up to about 60, and the sum of m and n is at least about 5; wherein the pH of the slurry is below 9.0 and the complex scale comprises gypsum.

[0014] In an embodiment of the invention, the pH can be from about 3.0 to about 9.0, typically greater than about 4.0 to about 9.0, can be from about 4.5 to about 9.0, and may be from about 5.0 to about 8.0. The process may be applied to mineral ore slurries with mineral ore having temperatures of up to about 550°C, can be up to about 450°C, can be up to about 400°C, may be from about 40°C to about 550°C, or from about 40°C to about 450°C. Persons of ordinary skill in these arts, after reading this disclosure, will appreciate that all ranges and values for the temperature ranges are contemplated. With respect to the active component of the anti-sealant composition, any of the active compounds discussed in this Specification may be used in the process.

[0015] The anti-sealant composition described herein may be used for controlling complex scale, typically gypsum scale, in mineral ore slurry forming and cooling operations; such as an ore quench operation or an autoclave operation, including any associated piping or ancillary equipment. In some aspects, such processes may comprise the steps of a) providing an ore quench tank having a vessel with an interior surface or an autoclave having an interior surface, at least one feed line having an interior surface and at least one discharge line having an interior surface; b) providing a mineral ore slurry comprising mineral ore and an aqueous phase; c) adding to the mineral ore slurry an effective amount of a scale inhibiting composition comprising an active component selected from the group consisting of i) a carboxylate polymer having the formula:

        R1-CH2-CH(CO2H)-R2-R3,

wherein R1 can be selected from the group consisting of a sulfonate, sulfate, phosphinate, phosphonate, an alcohol, 1,1-diphenylhexyl, tert-butyl, mercaptoethanol, mercaptopropionic acid, mercaptoglycolic acid, R2 is i) a polycarboxylate , and R3 is H or R1; and ii) a polyamine acid having the formula:

        poly(X)mPoly(Y)n,

wherein X and Y are independently selected from an amino acid and m is about 2 to about 60, n is up to about 60, and sum of m and n is at least about 5; wherein the pH of the mineral ore slurry in the vessel is below 9.0, can be from about 3.0 to about 9.0, can be greater than about 4.0 to about 9.0, can be from about 4.5 to about 9.0, can be from about 5.0 to about 8.0, and may be from about 7.0 to about 8.5.

[0016] In some aspects, the temperature of the mineral ore in the slurry, particularly in the quench tank, is up to about 550°C, can be up to about 450°C, can be up to about 400°C, from about 40°C to about 550°C, or from about 40°C to about 450°C. In some aspects the temperature ranges of the mineral ore in the slurry in an autoclave can be up to about 220°C, can be up to about 190°C, with a typical temperature gradient of from about 80°C to about 220°C, like about 80°C to about 190°C. Persons of ordinary skill in these arts, after reading this disclosure, will appreciate that all ranges and values for the temperature ranges are contemplated. With respect to the active component of the anti-sealant composition useful in this process, any of the active compounds discussed in this Specification may be used in the process.

[0017] Typically, the solids content of the mineral ore slurry, that is the amount of mineral ore (mineral ore content) in the slurry, is at least about 8%, at least about 10%, at least about 20%, at least about 30%. For example, the mineral ore slurry may have a solids content of about 8% to about 30%, including about 10% to about 20%, such as about 10% to about 15%. Persons of ordinary skill in these arts, after reading this disclosure, will appreciate that all ranges and values for the solids content are contemplated.

[0018] The mineral ore slurry generally comprises a mineral ore having a component selected from the group consisting of a precious metal, a base metal and combinations thereof. The mineral ore slurry can comprise a mineral selected from the group consisting of gold, aluminum, silver, platinum, copper, nickel, zinc, lead, molybdenum, cobalt, and the like, and combinations thereof. The mineral ore slurry may further comprise one or more of quartz, dolomite, calcite, gypsum, barite or muscovite, and the like, and combinations thereof.

[0019] The mineral ore slurry can comprise from about 5 ppm to about 300 ppm of the active component in the scale inhibiting composition per the aqueous phase. In some embodiments, the amount of active may be from about 15 ppm to about 250 ppm, can be from about 20 ppm to about 100 ppm, and may be from about 25 ppm to about 50 ppm. Persons of ordinary skill in these arts, after reading this disclosure, will appreciate that all ranges and values for the amount of active component are contemplated.

[0020] The complex scale, such as gypsum, may be present on the interior surface of at least one feed line, the interior surface of the vessel of the quench tank or autoclave, the interior surface of at the least one discharge line or combinations thereof, as well as on any internal mechanisms or devices. The scale inhibiting composition can be added to the mineral ore slurry in at least one feed line, in at least one discharge line, in the vessel of the quench tank or in the autoclave or combinations thereof.

[0021] An ore quenching operation, particularly applied with recovery of minerals and precious metals in the case of gold ore, is illustrated in Fig. 1. In the quenching operation 1, hot, dry calcine from an upstream unit operation, typically a roaster (not shown) is processed to a calcine cooler 2. After cooling, the calcine is fed through a feed line and/or launder line 3 to the quench tank 4. In the operation shown in Fig. 1, water is added to the calcine in the feed line and/or launder line 3 via cooling water feed pipe 13 prior to the quench tank 4 to form the mineral ore slurry that is cooled in the quench tank 4. After cooling, the mineral ore slurry exits the quench tank 4 through a discharge line 5 to downstream unit operations. Optionally, a portion of the aqueous phase of the mineral ore slurry may be circulated by pipes 6 and 6' from the quench tank to a scrubber 7 and back as part of the operation. Gaseous material can be vented from the scrubber through a vent pipe 8. In an alternative method, not shown, water is added to the calcine to form the mineral ore slurry in the vessel of the quench tank 4 and not in the feed line and/or launder line 3.

[0022] Alternative quenching operations comprise at least one preliminary quench device comprising a preliminary quench device vessel having a preliminary quench device vessel interior wall and providing water and hot, dry calcine wherein the water is added to the calcine in the preliminary quench device vessel to form the mineral ore slurry and complex scale is on the preliminary quench device vessel interior wall. In a further embodiment, the water is added to the vessel of the quench tank to form the mineral ore slurry instead of the in the preliminary quench device. The mineral ore slurry is transported to the quench tank from the preliminary quench device by the feed line and/or launder line. In these embodiments the scale inhibiting composition is generally added to the mineral ore slurry in the preliminary quench device vessel, the feed line and/or launder line, or can be added directly to quench tank and piping section coming out of quench tank depending on severity of scale formation and location of severe zones of scale formation, or combinations thereof.

[0023] Fig. 2 illustrates a mineral ore quenching operation 9 comprising two preliminary quench devices. In this operation 9, hot, dry calcine is transported from an upstream unit operation to first preliminary quench device 10. One skilled in the art will recognize that the first preliminary quench device will comprise a first preliminary quench device vessel having a first preliminary quench device vessel interior wall. Water is added to the hot, dry calcine in first preliminary quench device 10, typically within preliminary quench device vessel, to form the mineral ore slurry. The mineral ore slurry is conveyed from the first preliminary quench device 10 to a second preliminary quench device 11 through a means 12 to convey mineral ore slurry from the first preliminary quench device 10 to the second preliminary quench device 11 which, as one skilled in the art will appreciate, has a conveyance means interior wall. Typically, the means 12 is a pipe. One skilled in the art will also recognize that the second preliminary quench device 11 comprises a second preliminary quench device vessel having a second preliminary quench device vessel interior wall. Some cooling of the mineral ore slurry occurs in second preliminary quench device 11. After the second preliminary quench device 11 the mineral ore slurry undergoes similar processing as that shown in Fig. 1, however the mineral ore slurry is not formed in the feed line or launder line 3. The mineral ore from the second preliminary quench device 11 is sent to the quench tank 4 through feed line or launder line 3. After cooling, the mineral ore slurry exits the quench tank 4 through a discharge line 5 to downstream unit operations. Optionally, a portion of the water phase of the mineral ore slurry may be circulated by pipes 6 and 6' from the quench tank to a scrubber 7 and back to quench tank 4 as part of the operation. Gaseous material can be vented from the scrubber through a vent pipe 8. Cooling water may be added through pipe system 25 to one or more of the first preliminary quench device 10, second preliminary quench device 11 and quench tank 4 and scrubber 7. In this method, the scale inhibiting composition may be added to the mineral ore slurry in the first preliminary quench tank device 10, the second preliminary quench device 11, the means 10, feed line or launder line 3 or quench tank 4. Complex scale may form on the first preliminary quench device vessel interior wall, the second preliminary quench device vessel interior wall, conveyance means interior wall or combinations thereof, in addition to the mechanisms and internal components of the mineral ore quenching operation discussed above, including those discussed with the operation shown in Fig. 1.

[0024] Although Fig. 2 illustrates and operation comprising a first preliminary quench device 10 and a second preliminary quench device 11, operations comprising one or more than two of such devices, such as 3, 4, 5, 6, 7, 8, 9, 10, 11, 12 or more preliminary quench devices, are within the scope of the invention.

[0025] In some aspects, the temperatures of the for hot calcine ore entering the quench tank are very high, such as up to about 550°C and can be up to about 450°C. Typically, within the vessel, of the quench tank the temperature gradient for calcine can range from about 40°C to about 550°C, can be from about 40°C to about 450°C, with higher temperatures towards the top of quench tank. However, due to very short period of time for calcine slurry residence in the quench tank vessel and low pressure, the slurry aqueous phase bulk temperature should be not be higher than about 100°C.

[0026] Fig. 3 shows a typical autoclave process 14 used to for mineral ore slurries. Typically, these processes will be applied to oxidize mineral ore slurry comprising acid, such as sulfuric acid, using oxygen in a high pressure and temperature environment prior to leaching the mineral from the ore in aJ so called acid oxidation autoclave processes. Also, the circuits described herein may be used in alkaline oxidation autoclave processes. The anti-sealant compositions described herein can be used in both acid oxidation autoclave processes and alkaline oxidation autoclave processes. As shown in Fig. 3, mineral ore slurry is mixed with acid or base upstream of the autoclave and the mineral ore slurry enters one or more heating towers 15, which as shown in Fig. 3 may be in series, to preheat the slurry. The preheated slurry may then be sent through a heating tower discharge line 16 as shown in Fig. 3 to a condenser 17 and then to a feed line 18 to the autoclave 19. One skilled in the art will appreciate that the condenser 17 is optional and the mineral ore slurry can be sent through the feed line 18 to the autoclave 19 directly from a heating tower 15. Oxygen and steam may be added to the autoclave 19 such as in an acid oxidation autoclave process to oxidize the mineral ore slurry to oxidize sulfide material in the slurry, at high temperatures and pressure. The mineral ore slurry exits the autoclave 19 through a discharge line 20 to one or more cooling towers 21, which as shown in Fig. 3 may be in series, in which the slurry is cooled, for example, passing through flash cooling towers and then sent to downstream operations. Optionally, water phase from the mineral ore slurry may be circulated through a cyclone 22 through pipes 23 and 23'. Also, in certain embodiments, the mineral ore slurry may be processed via a heat exchanger feed line 26 through one or more heat exchangers 24 to further reduce slurry temperature prior to downstream processing. Typically, after the autoclave operation and subsequent cooling the mineral ore slurry undergoes neutralization and/or leaching. One skilled in the art will appreciate that although three heating towers and cooling towers and one autoclave are depicted in Fig. 3, the invention encompasses processes independently having any number of heating towers, cooling towers or autoclaves. Each of the pieces of equipment in the autoclaving operation such as shown in Fig. 3, including the heating towers 15, heating tower discharge line 161 condenser 17, feed line 18, autoclave 19, cooling towers 21, heat exchanger feed line 26 and heat exchanger 24, as well as other equipment and lines, will have interior surfaces or interior walls and possibly other mechanisms such as stirrers and heat exchange devices. Scale, such as gypsum scale, may form on any of the interior surfaces or walls or the surfaces of any internal devices exposed to the mineral ore slurry and any other associated equipment, pipes and lines.

[0027] The temperature of the mineral ore of the acidified mineral ore slurry in the pressurized autoclave is high, such as up to about 220°C, can be up to about 190°C. Typically, within the autoclave the temperature range for the mineral ore can be from about 80°C to about 250°C and may be from about 80°C to about 190°C. The pressure in autoclave operation can vary from about 400 kPa to about 4,000 kPa. Similar temperatures, but typically in a lower range specified above, may be experienced in the other equipment and piping associated with the autoclaving operation, such as, for example, the heating towers 15, condenser 17, cooling towers 21, a'":ld heat exchanger 24 and the associated equipment, pipes and lines. In alkaline oxidation autoclave process and slurry cooling circuits the typical pH range for ore slurry, discharged from high pressure autoclave, is below 9.0, more specifically between about 7.0 and about 8.5.

EXAMPLES



[0028] In the Examples, scale inhibition was analyzed using a Model KS 4000 ic IKA shaker bath with a set of 16 10 oz jars. The details of equipment, reagents and protocol are described below.

[0029] Examples using organic phosphonates as active components are reference examples.

Examples 1-15



[0030] Mimic water, that is water having salt content typically found in mining operations, particularly gold mines, was made by combining de-ionized water with the the following salts: CaCl2·2H2O, MgSO4·7H2O, Na2SO4, Al2(SO4)3, FeSO4·7H2O, CuSO4·7H20. The composition of the mimic water after gypsum formation is set forth in Table 1.
Table 1: Mimic water composition
Wt% GypsumCalcium, ppmMagnesium, ppmChlorides, ppmSulfates, ppmAl3, ppmCu2+, ppmFe2+, ppm
0.75 5690 3806 4034 10926 1.0 3.8 1.0
Where: Ca and Mg amounts are expressed as CaC03 and MgC03 respectively. Gypsum wt% corresponds to total amount of gypsum formed in situ in mimic water.


[0031] The mimic water was composed of proper salts to set gypsum scale in situ formation, with a small amount of polyvalent ions added. Gypsum scale super saturation ratio was kept constant for all examples.

[0032] For each Example 1-15, mimic water set forth in Table 1 was added to jars with the type and amount of scale inhibiting composition set forth in Table 2. Two jars with only mimic water and no scale inhibiting composition (controls) were also made up for comparison. The jars were placed in the IKA shaker bath with revolutions per minute ("rpm") kept constant at 130rpm and a temperature of 60°C with pH at 5.5 to 6.0. The tests typically lasted 16 to 18 hours to ensure sufficient time to reach the state of equilibrium for scale formation. The percent inhibition by mass was calculated using a proprietary mass balance method applied to Ashland's scale deposition test. The water, after filtering out of suspended scale/slurry, was submitted to ICP analysis and threshold inhibition was measured using ICP analysis by the amount of soluble Ca-ion and calculated by:



[0033] The results of percent(%) inhibition by ICP and percent(%) inhibition by mass of scale deposited are set forth in Table 2. All tests have been repeated 2 to 4 times on average to achieve good reproducibility.
Table 2: Deposition and threshold inhibition datafor scale inhibiting products in mimic water
Example#ProductProduct%Inhibition ICP% Deposition Inhibition by Mass
Comparative 1 50 ppm in water Polystabil AN (Batch 72.37 95.58
Comparative 2 25 ppm in water Polystabil AN (Batch 0.00 0.00
Comparative 3 50 ppm in water Baypure 71.37 96.15
Comparative 4 25 ppm in water Baypure 0.00 17.52
Comparative 5 50ppm in water Mayoquest 1635 72.33 97.48
Comparative 6 25 ppm in water Mayoquest 1635 0.00 -3.94
Comparative 7 50 ppm in water Polystabil AN (Batch 54.78 74.12
Comparative 8 25 ppm in water Polystabil AN (Batch 0.00 -2.48
Comparative 9 50 ppm in water Dequest 2066 5.70 -3.54
Comparative 10 25 ppm in water Dequest 2066 0.00 41.46
Comparative 11 50 ppm in water Drew 11-664 2.23 -11.59
Comparative 12 50 ppm in water Cublen 45 2.55 -18.01
Comparative 13 50 ppm in water Degapas 1105N 11.69 34.78
Comparative 14 50 ppm in water Polystabi I ANA 35.39 76.24
Comparative 15 50 ppm in water Polystabil VZK 52.70 80.66
Comparative 16 50 ppm in water Polystabil AN 25.06 49.25


[0034] In Table 2, product amount is expressed in ppm (parts per million or mg/L) of active ingredient per mimic water phase. Soluble Ca ion was measured by ICP. Total scale deposited, mass percent, was measured by a proprietary method.

[0035] The results summarized in Table 2 show a broad range of scale inhibition efficacy by both deposition and threshold mechanisms. Threshold inhibition varies from 0% to 100%. Polyacrylate, polyaspartate and organic phosphonate, HDTMPA, acid salts showed the best efficacy.

EXAMPLES 17 - 27



[0036] In Examples 17-27, dried mine slurry relevant to a quench tank circuit and having the compositions set forth in Tables 3 and 4 was re-dispersed at a given weight percent dose levels in water to obtain aqueous slurries.
Table 3: Slurry composition, Case 1
Slurry Components (Dry)Wt%
Quartz 67%
Dolomite 9%
Calcite 6%
Gypsum 5%
Barite 2%
Muscovite 11%
Table 4: Slurry composition, Case 2
Slurry Components (Dry)Wt%
Quartz 61%
Dolomite 18%
Calcite 3%
CaS04·H20 8%
Barite 8%
Muscovite -1%


[0037] In Examples 17-27, gold ore was added to the slurry described in Table 3 (Case 1) to obtain slurries having a gold ore (solids) content of 10% by weight. The slurries containing gold ore were placed in the jars as described above and the type and amount of scale inhibiting composition was added. The jars were then placed in the IKA shaker bath and processed as described above for Examples 1-16. Two control jars were also processed. After processing scale inhibition was measured using ICP analysis as described above and the results are set forth in Table 5.
Table 5: Threshold inhibition data for scale inhibiting products in mimic water with 10wt% gold ore slurry, Case 1.
Example#Product Amount*Product Type% Inhibition ICP
17 25 ppm in water Polystabil AN (Batch 75
18 25 ppm in water Baypure 53
19 25 ppm in water Mayoquest 1635 36
20 25 ppm in water Polystabil AN (Batch 33
21 25 ppm in water Dequest 2066 19
22 25 ppm in water Drew 11-664 16
23 25 ppm in water Cublen 45 14
24 25 ppm in water Degapas 1105N 11
25 25 ppm in water Polystabil ANA 7
26 25 ppm in water Polystabil VZK 6
27 25 ppm in water Polystabil AN 3
*In Table 5, product amount is expressed in ppm (parts per million or mg/L) of active ingredient per aqueous phase in mimic water, containing 10wt% gold ore slurry. Soluble Ca ion was measured by ICP.


[0038] Polyacrylate, polyaspartate and organic phosphonate, HDTMPA, acid salts showed good efficacy, while tested at half a dose level compared to mimic water conditions (Examples 1-16). The presence of suspended slurry unexpectedly enhanced inhibition.

Examples 28 - 44



[0039] In Examples 28 - 44, gold ore was added to the aqueous mimic water with the ore composition described in Table 4 (Case 2) to obtain slurries having gold ore (solids) content of 10% by weight and 15% by weight. The slurries containing gold ore were placed in jars described above and the type and amount of scale inhibiting composition was added. The jars were then placed in the IKA shaker bath and processed as described above for Examples 1-16. Two control jars were also processed. After processing, scale inhibition was measured using ICP analysis as described above and the results are set forth in Table 6.
Table 6 Threshold inhibition data for scale inhibiting products in mimic water with 10wt% and 15wt% (high solids) gold ore slurry, Case 2
Example#Product Amount*Product Type% Inhibition ICP
28 50 ppm in water Polystabil AN (Batch 16763) 49
29 50 ppm in water (high solids) Polystabil AN (Batch 16763) 45
30 50 ppm in water Baypure 55
31 50 ppm in water (high solids) Baypure 37
32 50 ppm in water Mayoquest 1635 62
33 50 ppm in water (high solids) Mayoquest 1635 16
34 50 ppm in water Polystabil AN (Batch 16764) 45
35 SO ppm in water Dequest 2066 27
36 50 ppm in water Drew 11-664 8
37 50 ppm in water Cublen 45 21
38 50 ppm in water (high solids) Cublen 45 3
39 50 ppm in water Degapas 1105N 47
40 50 ppm in water Polystabil ANA 4
41 50 ppm in water Polystabil VZK 58
42 50 ppm in water (high solids) Polystabil VZK 35
. 43 50 ppm in water Polystabil AN 45
44 50ppm in water (high solids) Polystabil AN 27
*Where product amount is expressed In ppm (parts per million or mg/L) of active ingredient per aqueous phase in mimic water, containing either 10wt% or 15wt% gold ore slurry. Soluble Ca ion was measured by ICP. Note that (high solids) are slurries having 15% by weight gold ore (solids) content, others without any notation as to solids have 10% by weight gold ore (solids) content.


[0040] Polyacrylate, organic phosphonate and polyaspartate show good inhibition performance. Organic phosphonate and polyaspartate performance decreases with the increase in the solids content, while polyacrylate product retains essentially the same inhibition performance as in the prior examples (17-27). This indicates that slurry type, composition and amount have an impact on scale inhibition.


Claims

1. A process for preventing/inhibiting/controlling complex scale in mining operations comprising adding to an aqueous mineral ore slurry, an effective amount of a scale inhibiting composition comprising at least one active component selected from the group consisting of

a) a carboxylate polymer having the formula

        R1-CH2-CH(CO2H) R2-R3

wherein R1 is selected from the group consisting of sulfonate, sulfate, phosphonate, phosphinate, alcohol, 1,1-diphenylhexyl, tert-butyl, mercaptoethanol, mercaptopropionic acid, and mercaptoglycolic acid; R2 is a polycarboxylate; and R3 is H or R1; and

b) a polyamino acid having the formula

        poly(X)mpoly(Y)n

wherein X and Y are independently selected from the group consisting of an amino acid and a salt of an amino acid, m can be from 2 to 60, n can be up to 60, and the sum of m and n is at least 5; and

wherein the pH of the mineral ore slurry is below 9.0.


 
2. The process of claim 1, wherein X and Y of the polyamino acid are independently selected from the group consisting of aspartic acid, glutamic acid, lysine, aspartate, glutamate, a salt of lysine; m is 5 to 12; n is up to 12 and the sum of m and n is 5 to 12.
 
3. The process for controlling complex scale of any preceding claim, further comprising the steps of

a) providing an ore quench tank having at least one feed line and at least one discharge line;

b) adding an aqueous calcine mineral ore slurry to the quench tank;

c) adding to the mineral ore slurry the an effective amount of a scale inhibiting composition as defined in any preceding claim, and wherein the temperature of the mineral ore entering the vessel is up to 550°C or from 40°C to 450°C.


 
4. The process of claim 3, wherein the mineral ore slurry has a solids content of from 8% to 30% by weight.
 
5. The process of claim 3 or 4, wherein the complex scale is gypsum.
 
6. The process of any one of claims 3-5, wherein the scale inhibiting composition is added to the mineral ore slurry in at least one feed line, in at least one discharge line, in the vessel or combinations thereof.
 
7. The process of any one of claims 3-6, comprising the step of providing calcine and water wherein the water is added to calcine in at least one feed.
 
8. The process of any one of claims 3-7, further comprising the steps of providing at least one preliminary quench device comprising a preliminary quench device vessel and providing water and calcine wherein the water is added to the calcine in the preliminary quench device vessel.
 
9. The process of any one of claims 3-8, comprising the step of adding the scale inhibiting composition to the mineral ore slurry in the preliminary quench device vessel, the feed pipe or combinations thereof
 
10. The process of any one of claims 3-9, comprising the step of providing a first preliminary quench and a means to convey mineral ore slurry from the first preliminary quench device to the second preliminary quench device and comprising the additional step of adding the scale inhibiting composition to the mineral ore slurry in the first preliminary quench tank device, the second preliminary quench device, the means to convey mineral ore slurry from the first preliminary quench device to the second preliminary quench device or combinations thereof.
 
11. The process of any preceding claim, wherein R2 is polyacrylic acid
 
12. The process of any preceding claim, wherein the polyamino acid is polyaspartic acid.
 
13. The process of any preceding claim, wherein the mineral ore slurry comprises at least one of:

(i) a mineral component selected from the group consisting of a precious metal, a base metal and combinations thereof;

(ii) a mineral selected from the group consisting of gold, aluminum, silver, platinum, copper, nickel, zinc, lead, molybdenum, cobalt and combinations thereof;

(iii) quartz, dolomite, calcite, gypsum, barite or muscovite;
wherein the mineral ore slurry preferably comprises from 5 ppm to 300 ppm of the active component in the scale inhibiting composition per the aqueous phase.


 
14. The process for controlling complex scale according to claim 1, further comprising the steps of

a) providing at least one autoclave, at least one feed line and at least one discharge line;

b) providing a mineral ore slurry comprising mineral ore and an aqueous phase;

c) adding to the mineral ore slurry the effective amount of a scale inhibiting composition, wherein the temperature of the mineral ore in the autoclave is up to 250°C.


 
15. The process of claim 14, wherein the scale inhibiting composition is added to the mineral ore slurry in at least one feed line, at least one discharge line, the autoclave or combinations thereof.
 
16. The process of claim 14 or 15, further comprising the additional step of providing at least one heating tower and at least one cooling tower and at least one heat exchanger wherein the mineral ore slurry is transported from at least one heating tower through the feed line to the autoclave and then to at least one cooling tower and at least one heat exchanger from the discharge line.
 
17. The process of any one of claims 14 to 16, wherein the scale inhibiting composition is added to the mineral ore slurry in at least one heating tower, at least one cooling tower, at least one heat exchanger or combinations thereof.
 


Ansprüche

1. Verfahren zum Verhindern/Hemmen/Beherrschen von komplexem Kesselstein bei Bergbauarbeiten, umfassend das Zugeben, zu einem wässrigen Mineralerzschlamm, einer wirksamen Menge einer Kesselsteinhemmzusammensetzung, umfassend mindestens eine aktive Komponente, ausgewählt aus der Gruppe, bestehend aus

a) einem Carboxylatpolymer mit der Formel

        R1-CH2-CH(CO2H)-R2-R3

wobei R1 aus der Gruppe ausgewählt ist, die aus Sulfonat, Sulfat, Phosphonat, Phosphinat, Alkohol, 1,1-Diphenylhexyl, tert-Butyl, Mercaptoethanol, Mercaptopropionsäure und Mercaptoglycolsäure besteht; R2 ein Polycarboxylat ist; und R3 H oder R1 ist; und

b) einer Polyaminsäure mit der Formel

        Poly (X)mpoly(Y)n,

wobei X und Y unabhängig aus der Gruppe, bestehend aus einer Aminosäure und einem Salz einer Aminosäure, ausgewählt sind, m 2 bis 60 betragen kann, n bis zu 60 betragen kann und die Summe aus m und n mindestens 5 beträgt; und
wobei der pH-Wert des Mineralerzschlammes unter 9,0 beträgt.


 
2. Verfahren nach Anspruch 1, wobei X und Y der Polyaminosäure unabhängig aus der Gruppe ausgewählt sind, die aus Asparaginsäure, Glutaminsäure, Lysin, Aspartat, Glutamat, einem Salz von Lysin besteht; m 5 bis 12 beträgt; n bis zu 12 beträgt und die Summe aus m und n 5 bis 12 beträgt.
 
3. Verfahren zum Beherrschen von komplexem Kesselstein nach einem vorhergehenden Anspruch, ferner umfassend die Schritte:

a) Bereitstellen eines Erzabschreckbehälters, der mindestens eine Speiseleitung und mindestens eine Ablassleitung aufweist;

b) Zugeben eines wässrigen Schlammes von kalziniertem Mineralerz zu dem Abschreckbehälter;

c) Zugeben einer wirksamen Menge einer Kesselsteinhemmzusammensetzung, wie in einem vorhergehenden Anspruch definiert, zu dem Mineralerzschlamm und wobei die Temperatur des Mineralerzes, das in das Gefäß eintritt, bis zu 550 °C oder 40 °C bis 450 °C beträgt.


 
4. Verfahren nach Anspruch 3, wobei der Mineralerzschlamm einen Feststoffgehalt von 8 Gewichts-% bis 30 Gewichts-% aufweist.
 
5. Verfahren nach Anspruch 3 oder 4, wobei der komplexe Kesselstein Gips ist.
 
6. Verfahren nach Anspruch 3 bis 5, wobei die Kesselsteinhemmzusammensetzung dem Mineralerzschlamm in mindestens einer Speiseleitung, in mindestens einer Ablassleitung, in dem Gefäß oder Kombinationen davon zugegeben wird.
 
7. Verfahren nach einem von Anspruch 3 bis 6, umfassend den Schritt des Bereitstellens von Kalzinierungsprodukt und Wasser, wobei das Wasser dem Kalzinierungsprodukt in mindestens einer Speisung zugegeben wird.
 
8. Verfahren nach einem von Anspruch 3 bis 7, ferner umfassend die Schritte des Bereitstellens mindestens einer Vorabschreckvorrichtung, umfassend ein Vorabschreckvorrichtungsgefäß, und des Bereitstellens von Wasser und Kalzinierungsprodukt, wobei das Wasser dem Kalzinierungsprodukt in dem Vorabschreckvorrichtungsgefäß zugegeben wird.
 
9. Verfahren nach einem von Anspruch 3 bis 8, umfassend den Schritt des Zugebens der Kesselsteinhemmzusammensetzung zu dem Mineralerzschlamm in dem Vorabschreckvorrichtungsgefäß, dem Speiserohr oder Kombinationen davon.
 
10. Verfahren nach einem von Anspruch 3 bis 9, umfassend den Schritt des Bereitstellens einer ersten Vorabschreckung und eines Mittels, um Mineralerzschlamm von der ersten Vorabschreckvorrichtung zu der zweiten Vorabschreckvorrichtung zu befördern, und umfassend den zusätzlichen Schritt des Zugebens der Kesselsteinhemmzusammensetzung zu dem Mineralerzschlamm in der ersten Vorabschreckbehältervorrichtung, der zweiten Vorabschreckvorrichtung, dem Mittel zum Befördern von Mineralerzschlamm von der ersten Vorabschreckvorrichtung zu der zweiten Vorabschreckvorrichtung oder Kombinationen davon.
 
11. Verfahren nach einem vorhergehenden Anspruch, wobei R2 Polyacrylsäure ist.
 
12. Verfahren nach einem vorhergehenden Anspruch, wobei die Polyaminosäure Polyasparaginsäure ist.
 
13. Verfahren nach einem vorhergehenden Anspruch, wobei der Mineralerzschlamm mindestens eines umfasst von:

(i) einer Mineralkomponente, ausgewählt aus der Gruppe, bestehend aus einem Edelmetall, einem Grundmetall und Kombinationen davon;

(ii) einem Mineral, ausgewählt aus der Gruppe, bestehend aus Gold, Aluminium, Silber, Platin, Kupfer, Nickel, Zink, Blei, Molybdän, Cobalt und Kombinationen davon;

(iii) Quarz, Dolomit, Calcit, Gips, Baryt oder Muskovit;
wobei der Mineralerzschlamm per wässriger Phase bevorzugt 5 ppm bis 300 ppm der aktiven Komponente in der Kesselsteinhemmzusammensetzung umfasst.


 
14. Verfahren zum Beherrschen von komplexem Kesselstein nach Anspruch 1, ferner umfassend die Schritte:

a) Bereitstellen mindestens eines Autoklaven, mindestens einer Speiseleitung und mindestens einer Ablassleitung;

b) Bereitstellen eines Mineralerzschlammes, umfassend Mineralerz und eine wässrige Phase;

c) Zugeben einer wirksamen Menge einer Kesselsteinhemmzusammensetzung zu dem Mineralerzschlamm, wobei die Temperatur des Mineralerzes in dem Autoklaven bis zu 250 °C beträgt.


 
15. Verfahren nach Anspruch 14, wobei die Kesselsteinhemmzusammensetzung dem Mineralerzschlamm in mindestens einer Speiseleitung, mindestens einer Ablassleitung, dem Autoklaven oder Kombinationen davon zugegeben wird.
 
16. Verfahren nach Anspruch 14 oder 15, ferner umfassend den zusätzlichen Schritt des Bereitstellens mindestens eines Heizturmes und mindestens eines Kühlturmes und mindestens eines Wärmeaustauschers, wobei der Mineralerzschlamm von mindestens einem Heizturm durch die Speiseleitung zu dem Autoklaven und dann zu mindestens einem Kühlturm und mindestens einem Wärmeaustauscher von der Ablassleitung transportiert wird.
 
17. Verfahren nach einem von Anspruch 14 bis 16, wobei die Kesselsteinhemmzusammensetzung dem Mineralerzschlamm in mindestens einem Heizturm, mindestens einem Kühlturm, mindestens einem Wärmeaustauscher oder Kombinationen davon zugegeben wird.
 


Revendications

1. Procédé de prévention/inhibition/régulation de tartre complexe dans les opérations minières comprenant l'ajout à une suspension aqueuse de minerai, d'une quantité efficace d'une composition d'inhibition de tartre comprenant au moins un composant actif sélectionné dans le groupe constitué par

a) un polymère carboxylate ayant la formule

        R1-CH2-CH(CO2H) R2-R3

dans laquelle R1 est sélectionné dans le groupe constitué par un groupe sulfonate, sulfate, phosphonate, phosphinate, alcool, 1,1-diphénylhexyle, tert-butyle, mercaptoéthanol, acide mercaptopropionique et acide mercaptoglycolique ; R2 est un polycarboxylate ; et R3 est H ou R1 ; et

b) un acide polyaminé ayant la formule

        poly(X)mpoly(Y)n

dans laquelle X et Y sont indépendamment sélectionnés dans le groupe constitué par un acide aminé et un sel d'un acide aminé, m peut être de 2 à 60, n peut être jusqu'à 60, et la somme de m et n est d'au moins 5 ; et
dans lequel le pH de la boue de minerai est inférieur à 9,0.


 
2. Procédé selon la revendication 1, dans lequel X et Y de l'acide polyaminé sont indépendamment sélectionnés dans le groupe constitué par l'acide aspartique, l'acide glutamique, la lysine, l'aspartate, le glutamate, un sel de lysine ; m est de 5 à 12 ; n est jusqu'à 12 et la somme de m et n est de 5 à 12.
 
3. Procédé pour réguler le tartre complexe selon l'une quelconque des revendications précédentes, comprenant en outre les étapes de

a) fourniture d'une cuve de trempe de minerai ayant au moins une ligne d'alimentation et au moins une ligne d'évacuation ;

b) ajout d'une boue de minerai de calcine aqueuse dans la cuve de trempe ;

c) ajout à la boue de minerai d'une quantité efficace d'une composition d'inhibition de tartre telle que définie selon l'une quelconque des revendications précédentes, et dans lequel la température du minerai qui entre dans le récipient monte jusqu'à 550 °C ou est de 40 °C à 450 °C.


 
4. Procédé selon la revendication 3, dans lequel la boue de minerai a une teneur en solides de 8 % à 30 % en poids.
 
5. Procédé selon la revendication 3 ou 4, dans lequel le tartre complexe est le gypse.
 
6. Procédé selon l'une quelconque des revendications 3 à 5, dans lequel la composition d'inhibition de tartre est ajoutée à la boue de minerai dans au moins une ligne d'alimentation, dans au moins une ligne d'évacuation, dans le récipient ou dans des combinaisons de ceux-ci.
 
7. Procédé selon l'une quelconque des revendications 3 à 6, comprenant l'étape de fourniture de calcine et d'eau dans lequel l'eau est ajoutée à la calcine dans au moins une alimentation.
 
8. Procédé selon l'une quelconque des revendications 3 à 7, comprenant en outre les étapes de fourniture d'au moins un dispositif de trempe préliminaire comprenant un récipient du dispositif de trempe préliminaire et fourniture d'eau et de calcine dans lequel l'eau est ajoutée à la calcine dans le récipient du dispositif de trempe préliminaire.
 
9. Procédé selon l'une quelconque des revendications 3 à 8, comprenant l'étape d'ajout de la composition d'inhibition de tartre à la boue de minerai dans le récipient du dispositif de trempe préliminaire, la conduite d'alimentation ou des combinaisons de ceux-ci.
 
10. Procédé selon l'une quelconque des revendications 3 à 9, comprenant l'étape de fourniture d'une première trempe préliminaire et d'un moyen pour transporter la boue de minerai du premier dispositif de trempe préliminaire vers le second dispositif de trempe préliminaire et comprenant l'étape supplémentaire d'ajout de la composition d'inhibition de tartre à la boue de minerai dans le premier dispositif de cuve de trempe préliminaire, le second dispositif de trempe préliminaire, le moyen pour transporter la boue de minerai du premier dispositif de trempe préliminaire vers le second dispositif de trempe préliminaire ou des combinaisons de ceux-ci.
 
11. Procédé selon l'une quelconque des revendications précédentes, dans lequel R2 est un acide polyacrylique.
 
12. Procédé selon l'une quelconque des revendications, dans lequel l'acide polyaminé est un acide polyaspartique.
 
13. Procédé selon l'une quelconque des revendications, dans lequel la boue de minerai comprend au moins un de :

(i) un composant minéral sélectionné dans le groupe constitué par un métal précieux, un métal de base et des combinaisons de ceux-ci ;

(ii) un minerai sélectionné dans le groupe constitué par l'or, l'aluminium, l'argent, le platine, le cuivre, le nickel, le zinc, le plomb, le molybdène, le cobalt et des combinaisons de ceux-ci ;

(iii) le quartz, la dolomie, la calcite, le gypse, la barytine ou la muscovite ;
dans lequel la boue de minerai comprend de préférence de 5 ppm à 300 ppm du composant actif dans la composition d'inhibition de tartre par phase aqueuse.


 
14. Procédé de régulation de tartre complexe selon la revendication 1, comprenant en outre les étapes de

a) fourniture d'au moins un autoclave, d'au moins une ligne d'alimentation et d'au moins une ligne d'évacuation ;

b) fourniture d'une boue de minerai comprenant un minerai et une phase aqueuse ;

c) ajout à la boue de minerai d'une quantité efficace d'une composition d'inhibition de tartre, dans lequel la température du minerai dans l'autoclave monte jusqu'à 250 °C.


 
15. Procédé selon la revendication 14, dans lequel la composition d'inhibition de tartre est ajoutée à la boue de minerai dans au moins une ligne d'alimentation, au moins une ligne d'évacuation, l'autoclave ou des combinaisons de ceux-ci.
 
16. Procédé selon la revendication 14 ou 15, comprenant en outre l'étape supplémentaire de fourniture d'au moins une tour de chauffage et d'au moins une tour de refroidissement et d'au moins un échangeur thermique dans lequel la boue de minerai est transportée d'au moins une tour de chauffage par le biais de la ligne d'alimentation vers l'autoclave et ensuite vers au moins une tour de refroidissement et au moins un échangeur thermique à partir de la ligne d'évacuation.
 
17. Procédé selon l'une quelconque des revendications 14 à 16, dans lequel la composition d'inhibition de tartre est ajoutée à la boue de minerai dans au moins une tour de chauffage, au moins une tour de refroidissement, au moins un échangeur thermique ou des combinaisons de ceux-ci.
 




Drawing














Cited references

REFERENCES CITED IN THE DESCRIPTION



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Patent documents cited in the description




Non-patent literature cited in the description