Pyrometallurgical Method for Recycling Shredded Material of Waste from the Production of New and Defective or End-of-Life Batteries for Electric Vehicles or Portable Li-Ion Batteries

Abstract

A pyrometallurgical process for recycling shredded spent electric vehicle batteries of Li-ion type and/or waste from the production of these new batteries and battery rejects, and/or portable batteries of Li-ion type. The process entails the addition of iron, smelting via the supply of energy, separation of a slag, oxidizing treatment and separation of a second slag.

Claims

1. A process for recovering black mass (100) derived from lithium batteries, characterized in that the process comprises an addition (E1) of an iron source (110) to the black mass to obtain a mixture, carburizing smelting (E2) of the mixture by supply of energy to obtain a carburized metal bath (130), separating a first slag (140), followed by oxidizing treatment (E3) of the carburized metal bath thus refined, and separation of a second slag (160) to obtain a ferroalloy (150).

2. The process for recovering black mass according to claim 1, characterized in that the carbon is chiefly provided by the graphite contained in the black mass and, if a supplement is needed, in the form of anthracite or substitution carbon material, for the purpose of smelting the mixture.

3. The process for recovering black mass according to claim 1, characterized in that agglomeration into pellets or briquettes, or extrusion is carried out before smelting.

4. The black mass recovery process according to claim 1, characterized in that smelting is conducted in a rotary converter (200) or converter equipped with an agitation device.

5. The black mass recovery process according to claim 1, characterized in that an addition of iron ore as iron source at about 94% iron oxide Fe2O3 to the battery black mass to obtain the mixture, is made in the proportion of ? iron ore quantity per 1 quantity of battery black mass.

6. The black mass recovery process according to claim 1, characterized in that the black mass is derived from shredded or dissembled lithium batteries.

7. The black mass recovery process according to claim 1, characterized in that slaked lime is added as binder to facilitate at least agglomeration of the black mass and iron ore as source of iron.

8. The black mass recovery process according to claim 1, characterized in that quicklime is added during the oxidizing treatment.

9. The black mass recovery process according to claim 1, characterized in that an operation of continuous production is carried out during which an addition of carbon is made to one fraction of the metal bath resulting from oxidizing treatment after separation of the second slag, this fraction being used to receive a new feed of black mass and iron source to form the mixture that is the subject of smelting to obtain the carburized metal bath.

10. The black mass recovery process according to claim 1, characterized in that the iron source is iron ore.

11. The black mass recovery process according to claim 1, characterized in that the iron source is oxidized or non-oxidized scrap iron.

12. The black mass recovery process according to claim 1, characterized in that additions of lime and magnesia to the mixture before carburizing smelting allow the obtaining of a first slag (140) having basicity indexes of: single basicity b=CaO/SiO2, of about 1.5, and global basicity B=(CaO+MgO)/(SiO2+Al2O3) of about 0.7?0.8.

Description

2. EXAMPLE

2.1. Composition of the Mix ?Black Mass+Fe Ore?

[0074] The black mass of the composition given in Table 3 is additioned with standard iron ore of 94% iron oxide Fe2O3, in the proportion of 1 t BM+0.5 t Fe ore. The result is the mix having the composition given in Table 4 below.

TABLE-US-00003 TABLE 4 Composition of the black mass + Fe ore mix Analysis: Black Mass + Fe ore mix % % % Ni 11.3 Co 4.7 S 0.22 Li 2.9 Mn 6.7 P 0.50 Fe 22.7 Cu 0.27 Ca 0.01 Al 0.73 C fix 28.0 HC 12.0

2.2. Mass Balances

2.2.1. Smelting

[0075] The smelting step is conducted in the converter with the mass balance given in Table 5a below.

TABLE-US-00004 TABLE 5a Mass balance of smelting 25 Kg flow/binder 1 t BM incl 280 kg C fix + + 500 Kg Fe ore gives 451 kg FeNiCoMnC+ 151 Kg slag yield << FeNiCoMnC >> 24.5 % Ni 0.5 % NiO 0.975 Ni 10.0 % Co 0.4 % CoO 0.970 Co 13.0 % Mn 5.6 % MnO 0.882 Mn 48.3 % Fe 3.8 % FeO 0.960 Fe 0.0 % Si 29.7 % CaO 0.970 Cu 0.57 % Cu 9.0 % Al2O3 1.00 Li (s) 3.5 % C 41.7 % Li2O 0.10 % S 1.14 % S 0.56 % P 1.68 % P 13 kg dust with 21.9 % NiO 9.0 % CoO 13.1 % MnO 3.8 % CaO

[0076] Per 1 t of black mass, smelting yields: [0077] 451 kg of FeNiCoMnC alloy, having the composition given in Table 4; an acceptable S content is ascertained (0.1%), but the P content (0.56%) is much too high for use as alloying raw material. The column on the right gives the yields of the metals recovered in the carburized alloy. [0078] 150 kg of Li-rich slag (in Li2O form); with recycling of the dust, a large part of Li is finally recovered in the slag. [0079] 13 kg of dust recovered in the gas treatment line via filtration, which is recycled back to the input mixture to be agglomerated.

[0080] Alternatively, the smelting step is conducted in the converter with the mass balance given in Table Sb below, which indicates an addition of lime CaO and magnesia MgO, to obtain the following ratios of basicity in the slag resulting from the smelting step: single basicity CaO/SiO2?1.5, and global basicity (CaO+MgO)/(SiO2+Al2O3) of 0.7 to 0.8.

TABLE-US-00005 TABLE 5b Mass balance of smelting 280 kg C fix + + 264 Nm3 O2 1 t BM incl 27 kg CaO/MgO/binder 500 Kg Fe ore gives 448 kg FeNiCoMnC+ 98 Kg slag << FeNiCoMnC >> 24.6 % Ni 0.7 % NiO 10.1 % Co 0.6 % CoO 13.1 % Mn 8.6 % MnO 48.1 % Fe 8.7 % FeO 0.0 % Si 20.6 % CaO 0.58 % Cu 6.8 % MgO 3.5 % C 20.6 % Al2O3 14.2 % SiO2 19.2 % Li2O 0.1 % S 1.58 % S 0.68 % P 2.04 % P 57 kg dust with 5.1 % NiO 2.1 % CoO 3.0 % MnO 77.3 % Li2O

[0081] Per 1 tonne of black mass, smelting yields: [0082] 448 kg of FeNiCoMnC alloy, still having the composition indicated in Table 4; the content of S is again found to be acceptable S (0.1%), but the P content (0.63%) is much too high for use as alloying raw material; [0083] 119 kg of slag containing partabout ?of the Lithium (in the form of 10-20% of the oxide Li2O); [0084] 57 kg of dust recovered in the gas treatment line by filtration, containing about ? of the Lithium in oxide form Li2O, which can extracted e.g. by hydrometallurgy. The remainder which contains valuable metals, especially Ni and Co, will be recycled back into the input mixture to be agglomerated.

[0085] The supply of energy for this smelting is provided by combustion of the Carbon (graphite C and hydrocarbons HC), by means of an addition of gaseous oxygen injected via a lance into the metal bath/slag. The amount of injected oxygen is about 260 Nm3/t of black mass (200 to 300 Nm3 per tonne of black mass depending on the exact composition).

2.2.2. Refining

[0086] The refining step entails extracting the Manganese by injecting oxygen, a metal that is readily oxidizable, at the same time that the Carbon, a large portion of Phosphorus and a portion of Iron are removed. A mass balance of this refining step is given in Table 6a.

[0087] At energy level, all these oxidization reactions are largely exothermal and more than cover reactor losses.

TABLE-US-00006 TABLE 6a Mass balance of refining 451 kg FeNiCoMnC + 100 kg CaO + 51 Mm3 0.8 gives 312 kg FeNiCo+ 257 O2 kg slag yield global << FeNiCo >> 35.0 % Ni 0.5 % NiO 0.99 Ni 0.965 14.4 % Co 0.2 % CoO 0.99 Co 0.960 0.8 % Mn 26.9 % MnO 0.04 Mn 0.847 48.8 % Fe 34.5 % FeO 0.7 Fe 0.672 0.8 % Cu 37.0 % CaO 0.99 Cu 0.960 0.0 % SiO2 0.1 % C 0.0 % Al2O3 0.069 % S 0.1 % S 0.081 % P 0.8 % P 14 kg dust with 0.5 % NiO 0.2 % CoO 26.9 % MnO 34.5 % FeO 37.0 % CaO

[0088] Per 1 t of black mass, refining therefore gives: [0089] 312 kg of FeNiCo alloy having the composition indicated in Table 5; acceptable contents of S (0.069%) and of P (0.081%) are found. The right-side column gives the yields of metals recovered in the FeNiCo alloyby distinguishing between the yield at refining and the global yield of the element starting from the black mass; [0090] 257 kg of slag with high content of Mn, Fe and lime; [0091] 14 kg of dust having a composition close to that of the slag, in which it can be incorporated before casting.

[0092] Alternatively, a mass balance of this refining step is given in Table 6b.

[0093] Per 1 tonne of black mass, refining gives: [0094] 311 kg of FeNiCo alloy having the composition indicated in Table 5; again acceptable contents are found of S (0.083%) and P (0.091%); [0095] 262 kg of slag with high content of Mn, Fe and lime; [0096] 8 kg of dust having a composition close to that of the slag to which it can be added before casting.

TABLE-US-00007 TABLE 6b Mass balance of refining 448 kg FeNiCoMnC + 100 kg CaO + 51 Nm3 gives 311 kg FeNiCo+ 262 O2 kg slag << FeNiCo >> 35.2 % Ni 0.5 % NiO 14.4 % Co 0.2 % CoO 0.8 % Mn 27.0 % MnO 48.5 % Fe 34.2 % FeO 0.8 % Cu 37.0 % CaO 0.0 % SiO2 0.1 % C 0.0 % Al2O3 0.083 % S 0.1 % S 0.091 % P 0.9 % P 8 kg dust with 0.5 % NiO 0.2 % CoO 27.0 % MnO 34.2 % FeO 37.0 % CaO

2.3. Upcycling Applications

[0097] The 3 products obtained have ensured reuse, of which the applications can be specified as follows: [0098] the FeNiCo alloy having 48 or 49% Fe, 35% Ni, 14% Co can advantageously be used to produce high alloy steels of Maraging type, used in aeronautics, and which typically contain 17?19% Ni, 8?12% Co. It could therefore replace supplies of Ni and Co raw materials in the form of ferroalloys; [0099] the slag and dust high in Li2O form a very rich Li ore that can readily be incorporated in the Li extraction and production industry via hydrometallurgical route; [0100] the slag FeOMnOCaO containing ?27% MnO (?21% Mn) will form a raw material of choice for carbothermal reducing furnaces producing ferromanganese. In these furnaces, routine use is made of 40% Mn ore, but large quantities of lime CaO are added thereto since high basicity of the slag promotes the yield of Manganese. The slag FeOMnOCaO resulting from recovery of the black mass will therefore replace a Manganese ore, an addition of lime CaO and an addition of Iron, all at the same time.

2.4. The Case of Low-Phosphorus Black Mass

[0101] A black mass free of Phosphorus or with low Phosphorus content is of close typical composition, an example of which is given in Table 7 below.

[0102] Here the content of Phosphorus is 10 times less than in the standard black mass.

TABLE-US-00008 TABLE 7 Typical composition of low-Phosphorus black mass. Analysis: Low P Black Mass % % % Ni 17.0 Co 7.0 S 0.20 Li 4.4 Mn 10.0 P 0.05 Fe 1.0 Cu 0.40 Ca 0.02 Al 0.80 C fix 28.0 HC 12.0

[0103] One application of reuse is evidently the one described for high Phosphorus content, comprising 2 steps (smelting and refining) ultimately leading to a low-Phosphorus FeNiCo alloy that can be used in the preparation of high alloy steels with high contents of Ni and Co.

[0104] The mass balances of this industry are grouped together in Tables 8a and 8b below.

TABLE-US-00009 TABLE 8a Smelting and refining mass balances for low-Phosphorus black mass. Smelting mass balance 25 kg flow/binder 1 t BM incl 280 kg C fix + + 500 kg Fe ore gives 451 kg FeNiCoMnC+ 151 kg slag yield << FeNiCoMnC >> 24.5 % Ni 0.5 % NiO 0.975 Ni 10.0 % Co 0.4 % CoO 0.970 Co 13.0 % Mn 5.6 % MnO 0.882 Mn 48.3 % Fe 3.8 % FeO 0.960 Fe 0.0 % Si 29.7 % CaO 0.970 Cu 0.57 % Cu 9.0 % Al2O3 1.00 Li (s) 3.5 % C 41.7 % Li2O 0.10 % S 1.14 % S 0.56 % P 0.17 % P 13 kg dust with 21.9 % NiO 9.0 % CoO 13.1 % MnO 3.8 % CaO Refining mass balance 451 kg FeNiCoMnC + 100 kg CaO + 49 Mm3 0.8 gives 312 kg FeNiCo+ 255 O2 kg slag yield global << FeNiCo >> 35.1 % Ni 0.5 % NiO 0.99 Ni 0.965 14.4 % Co 0.2 % CoO 0.99 Co 0.960 0.8 % Mn 27.1 % MnO 0.04 Mn 0.847 48.8 % Fe 34.7 % FeO 0.7 Fe 0.672 0.8 % Cu 37.2 % CaO 0.99 Cu 0.960 0.0 % SiO2 0.1 % C 0.0 % Al2O3 0.069 % S 0.1 % S 0.008 % P 0.1 % P 13 kg dust with 0.5 % NiO 0.2 % CoO 27.1 % MnO 34.7 % FeO 37.2 % CaO

TABLE-US-00010 TABLE 8b Smelting and refining mass balances for low-Phosphorus black mass. 1 t BM incl + 280 kg Cfix +/ 264 Nm3 O2 27 kg flow/ MgO/ + 500 kg Fe ore CaO gives 439 kg Fe NiCoMnC+ 97 kg slag << FeNiCoMnC >> 24.6 % Ni 0.7 % NiO 10.1 % Co 0.6 % CoO 13.1 % Mn 8.5 % MnO 48.1 % Fe 8.6 % FeO 0.0 % Si 20.8 % CaO 0.58 % Cu 6.9 % MgO 3.5 % C 20.5 % Al2O3 14.1 % SiO2 19.3 % Li2O 0.13 % S 1.6 % S 0.07 % P 0.21 % P 70 kg dust with 8.3 % NiO 3.4 % CoO 4.9 % MnO 63.0 % Li2O

[0105] However, it appears that the main poisonous element for the recycling of highly valuable metals (Ni and Co), namely Phosphorus, is in this case already quite largely removed at the smelting step at which it is lowered to less than 0.1% P in the FeNiCoMnC ferroalloy.

[0106] It is true that the standard analysis of FeNiCo alloys of ?Maraging? type comprises low Mn and C contents (often less than 0.2% each). Nonetheless there are possibilities of direct use of the FeNiCoMnC alloys, either by including these at a preliminary production phase (at which Mn and C are removed) or for derivative versions of these types of ferroalloy tolerating higher contents of Mn and C.

3. SUMMARY

[0107] Batteries of Li-ion type, as valuable elements it is crucial to properly recycle, comprise Copper Cu, Aluminium Al (2 metals contained in metallic form), Nickel Ni, Cobalt Co, Manganese Mn and evidently Lithiumthe latter in the form of combined oxides.

[0108] In known recovery channels, the recycling of these batterieswhether concerning production waste, spent batteries or faulty new batteriesincludes a size reduction step using a shredder which in good proportions separates Copper and Aluminium (metals), and produces a ?black mass? grouping together the other metals as well as a high proportion of carbon in elementary (C-Fix) or combined form, in plastics and oils similar to hydrocarbons.

[0109] Several solutions are currently proposed and are being tested to upgrade this black mass, most often via hydrometallurgical routeand in several steps.

[0110] In this document there is proposed a 3-step pyrometallurgical solution: [0111] Agglomeration of the black mass (pelleting, briquetting or extrusion)with the addition of iron ore and a suitable binder. [0112] Carburizing-reducing smelting in a rotary converter (or other type of converter equipped with an agitation device) allowing the Lithium to be separated in a slag and dust with high Li2O content, which are highly upgradable in industries currently producing this metal. Additions of lime and magnesia to the mixture, before carburizing smelting, allow the obtaining of a first fluid slag after overflow having basicity indexes of: single basicity b=CaO/SiO2 of about 1.5, and global basicity B=(CaO+MgO)/(SiO2+Al2O3) of about 0.7?0.8. This first slag contains lithium.

[0113] The main supply of energy for carburizing smelting is generally combustion of the Carbon in the black mass via injection of gaseous oxygen into the bath. [0114] Oxidizing refining in the same converter, or in a second specific converter, leads to an alloy of FeNiCo type containing about 50% (Ni+Co), which can be used for the preparation of high-strength steels (in particular steels used in aeronautics), and to a slag high in Manganese, in Iron and lime which forms an excellent raw material for furnaces producing Ferro-Manganese.