PROCESS FOR TREATING A MATERIAL
20230383376 · 2023-11-30
Inventors
Cpc classification
C01B39/02
CHEMISTRY; METALLURGY
International classification
C01B39/02
CHEMISTRY; METALLURGY
Abstract
A process for treating a material to remove sulphates or other impurities therefrom comprises a) subjecting the material to a leaching step to selectively dissolve sulphate-containing material or dissolve other impurities from the material and/or to passivate gypsum, b) separating a leach solution generated in step (a) from solids, and c) treating the solids from step (b). The solids from step (b) may be leached to dissolve Si and/or Al and the pregnant leach solution can be treated to precipitate zeolites. The process can be used to make zeolites from feed materials, including leached spodumene residue. Step (a) is a pre-wash/pre-leach step that removes impurities that could otherwise interfere with the zeolite precipitation step or require further processing of the pregnant leach liquor.
Claims
1. A process for treating a material to remove sulphates or other impurities therefrom, the process comprising: a) subjecting the material to a leaching step to selectively dissolve sulphate-containing material or dissolve other impurities from the material and/or to passivate gypsum, b) separating a leach solution generated in step (a) from solids, and c) treating the solids from step (b).
2. A method as claimed in claim 1 wherein the other impurities may comprise one or more of arsenic, boron, tungsten, phosphorus and vanadium.
3. A method as claimed in claim 1 or claim 2 wherein step (a) comprises a neutral leach or a water wash at neutral pH, or an alkaline leach.
4. A method as claimed in any one of claims 1 to 3 wherein step (a) is conducted to minimise or avoid dissolution of silicate/silicon components and aluminium components from the material.
5. A method as claimed in any one of the preceding claims wherein step (a) is conducted at a temperature of less than 50° C., or less than 40° C., or at ambient temperature, or without any additional heating, and an alkaline solution corresponding to 0.5 to 2M NaOH, or 0.5 to 1.5M NaOH, or 0.5 to 1.25M NaOH, or 0.5 to 1M NaOH is used, and the alkaline solution comprises a hydroxide solution or a carbonate solution or mixtures thereof.
6. A method as claimed in any one of the preceding claims wherein step (a) is conducted with a solids loading of approximately 50 to 250 g, or from 50 to 200 g, or from 100 to 200 g of leached spodumene residue per litre of leachant solution and a residence time of from about 0.25 to about 4 hours, or from about 0.5 to about 2 hours, or from about 0.5 to about 1 hour.
7. A method as claimed in any one of the preceding claims wherein step (a) reduces the amount of soluble gypsum or soluble sulphate or other impurities in the material by at least 50%, or by at least 60%, or by at least 70%, or by at least 80%, or by at least 90%, or around 90 The solids from step (a) have reduced levels of gypsum or sulphate and preferably have low levels of gypsum or sulphate, when compared to the starting material.
8. A method as claimed in any one of the preceding claims wherein less than 20% of the silicate/silicon components and/or aluminium components, or less than 10% of the silicate/silicon components and/or aluminium components, in the feed material are dissolved in step (a).
9. A method as claimed in any one of the preceding claims wherein the process comprises repeating steps (a) and (b) one or more times.
10. A method as claimed in any one of the preceding claims wherein step (c) comprises a leaching step to leach Si and/or Al into solution.
11. A method as claimed in claim 10 wherein the process comprises: c) leaching the solids from step (b) to dissolve aluminium and silicate into solution and form a pregnant leach solution containing dissolved aluminium and silicon/silicate, d) separating the pregnant leach solution from solids, and e) treating the pregnant leach solution to form zeolites.
12. A method as claimed in claim 11 wherein the pregnant leach solution containing dissolved aluminium and dissolved silicate that is generated in step (c) is separated from the solids and separated solids residue, which contains quartz, calcite and calcium hydroxide, is disposed of or sent for any other use.
13. A method as claimed in claim 11 or claim 12 wherein step (c) comprises leaching the solids with an alkaline leach solution corresponding to a 2M to 6M NaOH solution, or a leach solution corresponding to a 3M to 5M NaOH solution, or a leach solution corresponding to a 4M to 4.5M NaOH solution, or a leach solution corresponding to about 4M NaOH. T
14. A method as claimed in any one of claims 11 to 13 wherein a temperature in step (c) ranges from 50° C. up to the boiling point of the mixture at atmospheric pressure, or from 60° C. to 90° C., or from 60° C. to 80° C., or from 70° C. to 80° C., or about 70° C.
15. A method as claimed in any one of claims 11 to 14 wherein a leaching time of up to 6 hours, or from about 0.5 to about 6 hours, or from about 2 to about 4 hours, is used in step (c).
16. A method as claimed in any one of claims 11 to 15 wherein step (e) comprises adding an additional source of aluminium to the pregnant leach solution in order to ensure that there is sufficient aluminium present in the solution to obtain the correct ratio of silicon to aluminium in the solution to obtain the zeolite.
17. A method as claimed in any one of claims 11 to 16 wherein in step (e), the solution is aged at a temperature of from about 60 to 95° C. with agitation for a period of from about 1 to about 4 hours and optionally with addition of seed crystals.
18. A method as claimed in any one of claims 11 to 17 wherein the zeolites are separated from the solution and the solution is recycled to step (c).
19. A process as claimed in any one of the preceding claims wherein the material is one or more of leached spodumene residue, or leached jadarite residue, or a mining tailings containing silicate/silicon components and/or aluminium components, or a kaolin-containing material or a kaolinite-containing material, or a clay-containing material, or aluminium hydroxy-sulfates, fly ash, or colloidal silica.
20. A process for producing zeolites from leached spodumene residue, the leached spodumene residue including gypsum, the process comprising a) subjecting the leached spodumene residue to a leaching step to selectively dissolve gypsum from the leached spodumene residue and/or to passivate gypsum, b) separating a leach solution generated in step (a) from solids, c) leaching the solids from step (b) to dissolve aluminium and silicate into solution and form a pregnant leach solution containing dissolved aluminium and silicon/silicate, d) separating the pregnant leach solution from solids, and e) treating the pregnant leach solution to form zeolites.
21. A process as claimed in claim 20 wherein a solution recovered from step (e) is at least partly recycled to step (c).
Description
BRIEF DESCRIPTION OF DRAWINGS
[0076] Preferred features, embodiments and variations of the invention may be discerned from the following Detailed Description which provides sufficient information for those skilled in the art to perform the invention. The Detailed Description is not to be regarded as limiting the scope of the preceding Summary of the Invention in any way. The Detailed Description will make reference to a number of drawings as follows:
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DESCRIPTION OF EMBODIMENTS
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[0093] The optimal pre-wash/pre-leach conditions are 0.5-2M NaOH solution, 0.5-2 hours washing time with solids loading of 50-200 g/L at temperature of 50° C. or less. After the pre-wash/pre-leaching step, the gypsum phase is virtually undetectable. Some of the dissolved gypsum re-precipitates as calcium hydrate, in accordance with the following reaction:
Ca(SO.sub.4).sub.2*0.5(H.sub.2O)+2NaOH.fwdarw.Ca(OH).sub.2↓+Na.sub.2SO.sub.4+0.5H.sub.2O
[0094] Another option for the pre-wash is 0.5-2M Na.sub.2CO3 solution, 0.5-2 hours washing time with solids loading of 50-200 g/L at temperature of 50° C. or less.
Ca(SO.sub.4).sub.2*0.5(H.sub.2O)+Na.sub.2CO3.fwdarw.CaCO.sub.3↓+Na.sub.2SO.sub.4+0.5H.sub.2O
[0095] Some of the gypsum may be coated with calcium hydroxide, which acts to passivate that gypsum and effectively renders it inert to further leaching.
[0096] The pulp or mixture 14 is removed from pre-wash or pre-leaching vessel 12 and transferred to solid/liquid separation stage 16. In the flowsheet shown in
[0097] The solid phase 20 comprises leached spodumene residue having a lower gypsum/sulphate content, when compared to feed leached spodumene residue 10. In some embodiments, the solid phase 20 is subjected to a further pre-wash/pre-leach step before being sent to the leaching vessel 22. Although this option is not shown in
[0098] The solid phase 20 is transferred to leaching vessel 22, where it is mixed with alkaline solution 23. The alkaline solution 23 may comprise a molarity of about 4M. The leaching step conduct in vessel 22 occurs at a temperature of from 60 to 80° C., with 70° C. being preferred, with a residence time of from 0.5 to about 6 hours, with 2 to 4 hours being preferred. The solids loading in leaching step 22 is from 40 to 75 g/L.
[0099] Leaching step 22 selectively leaches aluminium and silicon/silicate into solution. Other components, such as quartz, calcite and calcium hydroxide and calcium hydrate, are not leached to any appreciable extent and remain with the solids phase.
[0100] The slurry mixture or pulp 24 is removed from leaching vessel 22 and supplied to solid/liquid separation stage 26. Filtration may be used in this solid/liquid separation step. The solids 28 are separated from the liquid phase 30. Liquid phase 30 comprises a pregnant leach solution containing dissolved aluminium and dissolved silicon/silicate. The pregnant leach solution 30 is fed to crystallisation stage 32. An additional source of aluminium 34, which may comprise sodium aluminate, may be supplied to crystallisation stage 32 to ensure that the correct ratio of aluminium to silicon is obtained to produce the desired zeolite, such as zeolite LTA. In crystallisation stage 32, the pregnant leach solution with added aluminate is heated up to 70 to 95° C. with agitation for 1-4 hours to cause zeolite, such as zeolite LTA, to precipitate. Seed crystals may also be added. The precipitated zeolites are removed at 36. The remaining solution following crystallisation is separated and sent via line 38 to be recycled back to the leaching stage 22. Although
[0101] The zeolites 36 may then be dried and recovered for use.
EXAMPLES
[0102] The test work was conducted using the following general procedure:
Pre-Wash Stage:
[0103] 1. The received leached spodumene (LS) residue was added to the caustic solution and stirred without heating. [0104] 2. Once the pre-wash reaction was completed in setting time, solids and liquids were separated through filtration. Depending on the total content sulfate in the residue, the pre-wash may require two stages.
The pre-washed residue was washed and used for selective leaching stage.
Leaching Stage:
[0105] 1. The synthetic caustic liquor with caustic concentration was stirred. [0106] 2. The solution was heated by a hotplate with a temperature feedback controller. [0107] 3. When the set-point temperature was reached, pre-washed samples were added to the heated solution. [0108] 4. Once the leaching reaction was completed in setting time, solids and liquids were separated through vacuum filtration.
The leached solution is then used for the precipitation of final zeolite products.
Crystallization Stage:
[0109] 1. The obtained solution from leaching stage is transferred into precipitation flask and precipitated at specified temperature and time with agitation. The agitation speed need to be specified (high agitation speed prefer) to control kinetics and product particle size. [0110] 2. To synthesis different types of zeolites, the extra silica or aluminium source may be needed to balance molar ratio of SiO.sub.2/Al.sub.2O.sub.3. [0111] 3. The solid product was separated from the solution by filtration, washed, dried in oven.
[0112] The test work was conducted on 4 different leached spodumene residues, designated as Feed A, Feed B, Feed C and Feed D. The feed samples had the following compositions:
TABLE-US-00002 Sample (%) Al.sub.2O.sub.3 SiO.sub.2 TiO.sub.2 Fe.sub.2O.sub.3 CaO Na.sub.2O K.sub.2O SO.sub.3 Feed A 14.85 42.3 0.04 0.63 18.55 0.23 0.38 5.4 Feed B 23.56 68.2 0.08 0.83 0.36 0.18 0.6 0.73 Feed C 19.0 53.6 0.04 1.44 7.85 0.54 0.68 8.37 Feed D 19.12 55.20 0.06 0.77 9.32 0.28 0.47 7.24
Example 1
[0113] Laboratory scale experimental work was conducted to investigate embodiments of the process in accordance with the present invention. The leached spodumene residue (Feed A), had the following approximate composition:
TABLE-US-00003 TABLE 1 Mineral phase based on XRF and XRD Concentration (%) Leached Spodumene, ½(H.sub.2O*Al.sub.2O.sub.3*4SiO.sub.2) ~52.7 Gypsum, syn (Ca(SO.sub.4)(H.sub.2O).sub.2) ~11.6 Quartz, syn (SiO.sub.2) ~7.4 Calcite, syn (Ca(CO.sub.3)) ~28.3
[0114] The following general synthesis procedure was used:
Pre-Wash Stage:
[0115] 1. The received leached spodumene (LS) residue was added to the caustic solution and stirred without heating. [0116] 2. Once the pre-wash reaction was completed for the desired time, solids and liquids were separated through vacuum filtration. [0117] 3. The pre-washed residue was washed and dried and then used for selective leaching stage.
Leaching Stage:
[0118] 1. A synthetic caustic liquor with caustic concentration was stirred. [0119] 2. The solution was heated by a hotplate with a temperature feedback controller. [0120] 3. When the set-point temperature was reached, samples of the solids from the pre-wash stage were added to the heated solution. [0121] 4. Once the leaching reaction was completed for the desired time, solids and liquids were separated through vacuum filtration. [0122] 5. The leached solution is then used for the precipitation/crystallisation of final zeolite products.
Crystallization Stage:
[0123] 1. The obtained solution from leaching stage is transferred into a precipitation flask and precipitated at specified temperature and time with agitation. [0124] 2. To synthesise different types of zeolites, extra silicate or aluminium source may be needed to balance molar ratio of SiO.sub.2/Al.sub.2O.sub.3. [0125] 3. The solid product was separated from the solution by filtration, washed, dried in oven.
Results:
Pre-Wash/Pre-Leach
[0126] A number of different leaching conditions were used in the pre-wash stage to try to determine the most appropriate leaching conditions. The leach solutions arising from these tests were analysed for aluminium content, sulphur content (which equates to sulphate dissolution or gypsum dissolution) and silicon content. In this step, it is desired that the leach solution has low levels of dissolved aluminium and silicon and high levels of dissolved sulphur/sulphate, which will indicate selective dissolution of the gypsum.
[0127] In order to investigate the effect of varying residence time in the prewash stage, a series of tests at 50 g/L solid loading, 2 hours residence time and 1M sodium hydroxide solution at room temperature with agitation were conducted. The following solution analyses were obtained:
TABLE-US-00004 TABLE 2 Elemental concentration (mM) Al SO.sub.4 Si 0.25 h 2.11 31.34 7.81 0.5 h.sub. 1.28 29.8 7.93 1 h 0.90 31.34 8.33 2 h 0.63 31.71 8.71
[0128] These tests showed that a leaching time of from 0.25 hours to 2 hours produce acceptable results. The dissolved aluminium content likely decreases with time due to precipitation of aluminosilicates.
Leaching Stage
[0129] The solid residue obtained from the prewash stage was subsequently treated under varying leaching conditions and the dissolved Al concentration in the pregnant leach solution is shown in
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[0131]
[0132] Under conditions of solid loading of 50 g/L, varying leaching time and 4M sodium hydroxide solution, 70° C. with agitation, the following elemental concentrations were achieved in the pregnant leach solution at various leaching times:
TABLE-US-00005 TABLE 3 Elemental concentration (mM) Al SO.sub.4 Si 0.5 h.sub. 28.24 0.52 44.14 1 h 48.45 0.70 86.88 2 h 69.39 0.74 134.54 4 h 94.43 1.45 202.02
[0133] Again, these results show that a leaching time of up to 4 hours gave good results, with low concentrations of sulphate are maintained in the pregnant leach solution.
Crystallisation Stage
[0134] In the crystallisation stage, zeolite LTA was crystallised/precipitated. For leached spodumene (H.sub.2O*Al.sub.2O.sub.3*4SiO.sub.2), its molar ratio of SiO.sub.2 to Al.sub.2O.sub.3 is 4 while the molar ratio is 2 for the zeolite LTA (Na.sub.2O*Al.sub.2O.sub.3*2SiO.sub.2*4.5H.sub.2O). Consequently, extra aluminate needs to be added during the crystallization stage to achieve the stoichiometric ratio required for zeolite LTA. With this in mind, sodium aluminate was added to the pregnant leach solution.
[0135] The crystallisation stage was conducted in the laboratory trials by adding sodium aluminate to the pregnant leach solution at room temperature and then ageing the mixture for 15 to 30 minutes, followed by heating up to 80 to 95° C. with slow agitation for 1 to 4 hours. Zeolite LTA crystallised and was separated from the solution by filtration, washed and dried in an oven.
[0136] The solution using the crystallisation stage was analysed for its various components and the results are shown below:
TABLE-US-00006 TABLE 4 Elemental concentration (mM) Al SO.sub.4 Si Before adding 82.76 3.07 172.7 sodium aluminate After adding sodium 126.5 2.64 127.8 aluminate-1 hr After adding sodium 76.10 2.82 72.16 aluminate-2 hr After adding sodium 60.97 2.13 58.38 aluminate-4 hr
[0137] A photomicrograph of the zeolite LTA produced in this example is shown in
Example 2
[0138] The particle size distribution for Feed B is shown in
[0139] Feed B was subjected to a pre-wash step under conditions of 0.5˜1M NaOH, 0.5˜1 h washing time with solid loading 100˜200 g/L at room temperature. Solution samples were taken at various times during the pre-wash step and analysed for Al, SO.sub.4 and Si content in the solution. The following results were obtained:
TABLE-US-00007 TABLE 5 Al SO.sub.4 Si Elemental Con.(mM)_0.5M NaOH, 100 g/L solid loading 0.25 h 4.82 7.36 3.22 0.5 h.sub. 5.56 6.72 4.91 1 h 8.12 6.67 9.58 Elemental Con.(mM)_0.5M NaOH 200 g/L solid loading 0.25 h 8.04 13.52 3.68 0.5 h.sub. 7.78 13.47 4.81 1 h 7.77 13.61 7.51
[0140] The solids from the pre-wash step were then leached at 50-75 g/L solid loading, 4M NaOH at 70° C. for 2 hours. Samples of the leach solution were taken at various times during the leaching step and analysed for Al and Si concentration. The following solution analysis results were obtained:
TABLE-US-00008 TABLE 6 Elemental Concentration (mM) Al Si 0.5 h.sub. 50.60 141.52 1 h 74.87 203.44 2 h 75.21 224.82 3 h 69.56 230.10 4 h 66.90 241.82
[0141]
[0142] The pregnant leach solution then underwent a precipitation process under conditions of 70° C. with 10 g/L of seeding. As the initial pregnant leach solution has higher Si concentration than Al as shown in Table 6, we added extra Al source (aluminate solution) to make up the pregnant solution with Al and Si ratio around 1. Samples of the solution in the precipitation step were withdrawn at various times and analysed for Al, SO.sub.4 and Si content. The following results were obtained:
TABLE-US-00009 TABLE 7 70° C., Al SO.sub.4 Si 10 g/L seeding (hrs) (mM) (mM) (mM) 0 138.82 3.17 128.22 0.5 126.26 3.12 115.92 1 117.32 3.06 105.32 1.5 77.82 2.90 64.43 2 69.74 2.75 56.24 2.5 68.92 3.10 55.53 3 66.47 3.34 53.23
[0143] It can be seen that the SO.sub.4 content in solution remained at a very steady level, indicating that SO.sub.4 was not being precipitated with the zeolites. Analysis of the zeolites indicated that essentially pure zeolite LTA was obtained. In contrast, precipitation at 80° C. and otherwise identical conditions resulted in the formation of a mixture of zeolite LTA and sodalite.
Example 3
[0144] Due to the high sulphate content, Feed C was subjected to a 2 stage pre-wash step under the following conditions: [0145] Step 1) 1M NaOH, 200 g/L solid loading, room temperature [0146] Step 2) 1M NaOH, 200 g/L solid loading, room temperature.
[0147] Samples of the pre-wash solution were taken at various times and analysed for Al, SO.sub.4 and Si content. The following results were obtained:
TABLE-US-00010 TABLE 8 Al SO.sub.4 Si (mM) (mM) (mM) 1M NaOH, 200 g/L solid loading, Stage 1 0.25 h 0.02 168.44 0.38 0.5 h.sub. 0.05 158.27 0.4 1 h 0.03 151.76 0.45 1M NaOH, 200 g/L solid loading, Stage 2 0.25 h 0.13 7.95 0.93 0.5 h.sub. 0.21 8.83 1.14 1 h 0.18 9.88 1.19
[0148] The optimal pre-wash condition for feed C was found to be 0.5˜1 M NaOH, 0.5˜1 h for two stages due to high sulfate content with solid loading 100˜200 g/L at room temperature.
[0149] The solids from the second pre-wash step was then leached at various temperatures and solids loadings.
[0150] The pregnant leach solution then underwent a precipitation process under conditions of 70° C. with 10 g/L of seeding. Samples of the solution in the precipitation step were withdrawn at various times and analysed for Al, SO.sub.4 and Si content. The following results were obtained:
TABLE-US-00011 TABLE 9 70 degree C., Al SO4 Si 10 g/L seeding (hrs) (mM) (mM) (mM) 0 178.35 4.96 178.55 0.5 156.39 4.94 155.90 1 146.61 4.65 147.06 2 146.21 5.05 146.45 3 90.84 4.89 91.68
[0151] The precipitated zeolites were analysed and found to be pure zeolite LTA, as shown in
Example 4
[0152] Example 4 details preliminary experimental work on Feed D.
[0153] Although Feed D also has a high sulphate content, it is not as high as Feed C, and a single stage pre-wash was found to be suitable. The optimal pre-wash condition was found to be 0.5˜1 M NaOH, 0.5˜1 h with solid loading of 50˜100 g/L at room temperature.
[0154] Solution samples were taken at various times during the pre-wash step and analysed for Al, SO.sub.4 and Si content in the solution. The following results were obtained:
TABLE-US-00012 TABLE 10 Al SO4 Si (mM) (mM) (mM) 1M NaOH, 100 g/L solid loading 0.25 h 1.42 75.48 1.62 0.5 h.sub. 1.11 76.35 1.79 1 h 1.18 77.94 2.40 1M NaOH, 50 g/L solid loading 0.25 h 0.82 41.34 2.86 0.5 h.sub. 1.39 41.30 3.29 1 h 1.87 41.89 3.64
[0155] The solids from the pre-wash step were then subjected to leaching at conditions ranging from 50-75 g/L solids loading, 4M NaOH solution, 4.5M NaOH solution, a synthetic solution containing 4M NaOH and 60 mM AL and Si, and a synthetic solution containing 4.5M NaOH and 60 mM Al and Si. Solution analyses were conducted to determine Al concentration in solution vs time for each solution used and the results are shown in
[0156] From
TABLE-US-00013 TABLE 11 70 degree C., Al SO4 Si 4.5M NaOH(hrs) (mM) (mM) (mM) 0 60.89 0 64.05 0.5 78.42 4.63 94.41 1 94.29 4.67 127.49 2 107.50 4.61 165.51 3 73.82 4.23 152.06 4 33.18 2.88 137.70
[0157] The leaching solution was then subject to precipitation to form zeolites, using conditions of 70° C. for 4 hours, with a solution analysis vs time being shown in Table 12. As the initial pregnant leach solution has higher Si concentration than Al, we added extra Al source to make up the pregnant precipitation solution with Al and Si ratio around 1.
TABLE-US-00014 TABLE 12 70 degree C., Al SO4 Si 20 g/L seeding (hrs) (mM) (mM) (mM) 0 168.39 1.62 167.39 0.5 161.79 1.53 152.26 1 139.79 1.44 131.89 2 153.5 1.57 140.71 3 78.95 1.75 142.68
[0158] An analysis of the zeolites obtained showed that pure zeolite LTA was obtained, as shown in
[0159] Although the experimental work conducted above all related to a process for treating leached spodumene residue, the present inventors believe that the pre-wash step (which is step (a) of the present invention) will also be effective to selectively remove sulphates and other impurities, such as arsenic, boron and vanadium, from a feed material without dissolving significant amounts of other potentially valuable materials, such as Si or Al, in the feed material, thereby allowing for later treatment of the solid material from the pre-wash step to recover or utilise those other valuable materials, for example, to form zeolites. Therefore, the present invention should not be considered to be limited to treatment of leached spodumene residue. Rather, the present invention, in general terms, is directed towards impurity management in a feed material so that the impurities are removed from the solids, thereby facilitating downstream treatment of the solids. In some embodiments, the downstream processing of the solids involves leaching the solids to dissolve Si and/or Al, and subsequently forming zeolites from the leach solution. However, other downstream processing steps may also be used to recover or form valuable materials from the pre-washed solids.
[0160] Throughout this specification and claims (if any), the word ‘comprising’ and its derivatives including ‘comprises’ and ‘comprise’ include each of the stated integers but does not exclude the inclusion of one or more further integers.
[0161] Reference throughout this specification to ‘one embodiment’ or ‘an embodiment’ means that a particular feature, structure, or characteristic described in connection with the embodiment is included in at least one embodiment of the present invention. Thus, the appearance of the phrases ‘in one embodiment’ or ‘in an embodiment’ in various places throughout this specification are not necessarily all referring to the same embodiment. Furthermore, the particular features, structures, or characteristics may be combined in any suitable manner in one or more combinations.
[0162] In compliance with the statute, the invention has been described in language more or less specific to structural or methodical features. It is to be understood that the invention is not limited to specific features shown or described since the means herein described comprises preferred forms of putting the invention into effect. The invention is, therefore, claimed in any of its forms or modifications within the proper scope of the appended claims (if any) appropriately interpreted by those skilled in the art.