LU81040A1 - LEAD-COPPER-SULFUR LOAD TREATMENT PROCESS - Google Patents

Description

"Electric oven III" 2.4173 ow

SA Λ / (A \ ND-DUCHÉ DE LUXEMBOURG

......... I ü. * U

of __________ 14 ..... m.a.r.s ....... 1.9.7.9 .. ggm Mr. Minister ". of the National Economy and the Middle Classes

Title issued: _____________________________________ J

Industrial Property Service

7Γ ~ Tù ’'Ι & Λ? LUXEMBOURG

‘U‘1

/ CERTIFICATE OF ADDITION

• -K f. Patent application 4 'to main patent no 75,732 ..... of ...... 6 ..... September 1975 I. Request * .... La · .... société · anonyme dit .: METALLURGIE HCEOKEI ^ ÜVERPELX, 8 .., .rue .. (i>

Jion.tag.ae ..... du ...... Parc, ...... Er uxe.ll.es, ... Ee.Ig..i.aue .., .... .represented by............................. .............

Jlun.s..ie.ur .... C..fiar.les ...... ". UacMiu ...... slo.mj.11 ...... en ..... b.rie.vjts ..... i ..... LuxemboMro, ________________ (2) ... agis.sant .... in ..... quality ...... d.fi. ....representative............................................. .................................................. .........................................

deposit this φΐ £ ± .0..ΓΖ 6 MM .19.00 SXLiXÄJllfirllX - UfiJJLf ________________________________ (3) at .1.5 .. · .OO ... hours, at the Ministry of National Economy and the Middle Classes, in Luxembourg: 1. the present request for obtaining a bXev.st/dîib'ifëtttiOti concerning: i .............................. .................................................. .................................................. ....................... ce rtillc-Bt ..... dl. £ .dditiGn ............. .................... (4) ..... ".. RracMé ..... de ..... tr.aits-: jnt. ... of ...... c..ba.rj.M ^^ .............................. ........

declares, assuming responsibility for this declaration, that the inventor (s) is (are): .... '' ^ nsi-syr ......... £ c.Lt..r. .t..l '.. i..es .., ...... Fs..pe.ls..t.ra.at .... LLL, ...... £ M £. .... Eî-lj., ...... 3g.lglß.uS. "....... (5) .... st ....." £.!:. £ i. £ .ur .... Lut ..... £ .c.2.ta.ln £ .s .., ..... IeatocriS. ± elliuçsl & .sn .... 19 ,. .... 2.02.0 .................................

. ..An tvarp · ^ -, ...... Γ lie ................................. .................................................. .................................................. .................................................. ...............

2. the delegation of power, dated ............ <1 ........ J. i .:; ............................ on ......... LJ ....... . * ........ LP.LP

3. description in language ί..0. £ L ..- .. V..12.S ................ .......— of the invention in two copies; 4 ............. 1 .................. drawing boards, in two copies; 5. the receipt of the taxes paid to the Luxembourg Registration Office on .............. 14 ..... r-ars ..... 13X91 .... .................................................. .................................................. .................................................. .................................................. .....

claims for the above patent application the priority of one (s) request (s) of (6) -......................... / / ........................................ ......... ........... filed in (7) .......................... .././ . — ................................................ ......................................

the ......................................./·/....... .................................................. .................................................. .................................................. .................................................. ............. (8) .................................. ................................ // ................ .................................................. .................................................. .................................................. ..........................................

on behalf of .............. //............................... .................................................. .................................................. .................................................. ..... (9) elect domicile for him / her and, if designated, for their proxy, in Luxembourg ------------------------ ---------------- ..... lia ....... l. £ nd .rLln.c..ar: l. ': r; ri. .................................................. ........... ....................................... ...................................... (io) requests the delivery of an object described and represented in the appendices ~ above, - with ajojtrh ^ rnent of this delivery to —îXLXTjILjlΗ month.

On ........ / II. Deposit Minutes

The above request from ÜrfevJf xdflyyéptjig island deposits! * At the Ministry of National Economy T and the Middle Classes, Industrial Property Service in Luxembourg, dated: ► J-g— <j_-s 1) 79 / d? * ty \ Pr. the Minister at 15 ..... 0.0. hours / £ r National economy from Middle Classes, T g ra & dd s. | àC- eus \ W JJ φ · Γ './ a A 68007 _______IL________J________ j a.

"

V

DESCRIPTIVE MEMORY

filed in support of an application for

PATENT OF ADDITION

in PATENT OF INVENTION N ° 75-752 of September 6, 1975 in the name of the so-called public limited company

HOBOKEN-OVERPELT METALLURGY

for: "Process for treating lead-copper-sulfur charges." > r "; , - 2 -

Patent No. 75,732 relates to a process for treating Pb-Cu-S charges containing! minus one of the elements Fe, Ag, Bi, Zn and Sn, comprising the steps of] '(a) the fusion of the charge while maintaining conditions such that the fusion produces a slag phase containing at least about 10 $ Pb, a phase of copper mat containing less than about $ 65 Or and a lead phase of work, (b) separation of the slag and mat phases! • copper and lead lead produced in !: step (a), and (c) reduction of the slag phase separated in step (b), in the molten state while maintaining conditions such that the reduction lowers the lead content in the slag phase to a value i, less than about $ 2, and in which steps (a) and (c) are carried out in two separate reactors.

According to this patent, each of these two reactors advantageously consists of an electric submerged arc furnace, that is to say of a stationary furnace in which electrical energy is supplied by means of electrodes immersed in the slag and connected to an alternating voltage source.

It has now been found that it may be useful to replace at least one of these ovens with a tilting furnace / A '/

fitted with nozzles. / M

/ / 4 - 3 - This is how we can use a unit made up of two separate and independent reactors (see attached figure), each being similar to a part of the QS1 reactor. the QSL reactor was described in the brochure "Metallgesellschaft AG / Revievi of the Activities / Edition 20 - 1977 / lead-Material" With a Future ", p. 51-53. the QSL reactor consists of an elongated cylindrical furnace tiltable where lead sulphide concentrates are loaded from above at one end of the furnace. At the same end, oxidation is carried out by means of nozzles blowing into the liquid bath contained in the furnace. The metal obtained by roasting and reacting flows continuously from the reactor, while the slag produced by the same reactions flows towards the opposite end where nozzles also placed in the bottom of the reactor make it possible to reduce the non-ferrous metals by injecting reducing agents .

In the first of these two reactors, which is similar to the oxidizing part of the QSL reactor, the lead-copper-sulfur charge is fed and melted under conditions such that the fusion produces a slag phase containing at least about 10 $ Pb , a matte phase containing less than about. $ 65 Cu, a working lead phase and possibly an arsenical alloy phase collecting most of the * nickel. The slag is separated on one side of the reactor and the other phases on the other side; these other phases are then separated from one another by known devices located outside the reactor, the dust produced ^ sy / "- 4 - in the first reactor are normally recycled with the load; the gases, which are rich in SO2 "are normally sent to a sulfuric acid production facility. The slag containing at least about 10 $ Pb is fed to the second reactor, which is similar to the reducing part of the QSL reactor. It is reduced there in the molten state while maintaining conditions such that the reduction lowers the lead content of the slag phase to a value less than about $ 2 and, preferably, between about $ 0.15 and about 1 $. In these conditions, there is also produced a working lead phase and possibly an arsenical alloy phase collecting most of the cobalt, as well as zinc-rich dust.

The spent slag is withdrawn from the reactor on the opposite side to that where the lead-rich slag is supplied. The other phases are drawn off on the same side and separated from one another by known devices located outside the reactor. Zinciferous dust is normally treated in a zinc factory to extract the contained metals. The gases, which are poor in SO2, can be released to the atmosphere.

* Optionally, the two reactors can be siphon converters, as described in US Pat. No. 3,522,937 "suitable for continuous operation.

When the lead-copper-sulfur charge supplied to the first reactor is made up mainly of materials, f / 5- "sulphides, the energy necessary to melt the charge can be provided entirely by the combustion of the sulphides by means of the oxygen injected into the liquid bath contained in the reactor. When the charge contains increasing proportions * of non-thermogenic materials, such as sulphated or oxidized materials, the energy required for melting must gradually be supplied by another source. This is most easily done by direct combustion of a fuel such as coal or natural gas, 1 injected in mixture with oxygen by the nozzles blowing into the liquid bath. Ultimately, when the charge only contains non-thermogenic materials, all of the fusion energy must be provided by combustion of a stoichiometric mixture of fuel and oxygen injected by the nozzles. By way of illustration, when the load consists mainly of sulphides, the flow of oxygen to be injected into the bath is of the order of 140 Nm 3 per tonne of load. If the load consists mainly of non-thermogenic materials, approximately 50 ITm3 of natural gas and 100 Nm3 of oxygen must be injected per tonne of load. With charges made up of half of sulphides and half of non-thermogenic materials, the flow rates to be injected will be around 25 Um3 of natural gas and 120 Um3 of oxygen per tonne of charge.

A disadvantage of injecting high gas flows into the bath is that it causes a volat il i & eùiori! - 6 -. »Bearing lead, which is found in the dust from the reactor and must be recycled with the load. The dust production thus reaches approximately 1.4 kg per Nm3 of gas, injected. For example, with the flow rates mentioned above, which are of the order of 140 Nm3 per tonne of load, the production of dust reaches approximately 200 kg per tonne of load. To remedy this, it is advantageous to replace the combustion energy introduced into the nozzles by electrical energy, which is introduced for example by means of electrodes immersed in the slag and connected to a source. of alternating voltage. Ultimately, when the load consists mainly of non-thermogenic materials, the injections can be completely eliminated by providing all of the required energy in electrical form. The reactor then becomes an electric furnace with i (immersed electrodes. In this case, it is even still

L

It is possible to treat feeds containing a certain proportion of sulfur-containing materials by introducing them from the top of the furnace in admixture with oxygen or an oxygen-containing gas under conditions such that these sulfur-containing materials are at least partially roasted! . before joining the liquid bath contained in the oven.

"! In the second reactor, where the slag is fed. · Containing at least about 10 $ Pb, the reduction of this slag can be done for example by injection of coal dust, while the energy consumed by the reduction reactors, by the thermal losses of the reactor and by bringing the exhausted slag to temperature, it can be introduced by the combustion of a mixture of natural gas and oxygen injected at the same time as the coal dust.

when the Pb content of the spent slag is lowered to the level of about $ 2, the volatilization of the zinc is relatively low, so that the energy requirements are relatively low. On the other hand, when the Pb content of the spent slag is lowered below approximately $ 1, the energy requirements corresponding to the reduction of the zinc and to the thermal losses of the reactor increase. By way of illustration, if a slag containing JO $ Pb and 105¾ Zn is fed into the reactor and reduced to 0.5 $ Pb and Z ° / o Zn, the need for a reducing agent is d '' around 40 kg of coal per tonne of slag supplied and the energy requirements require the injection of approximately 68 Nm5 of natural gas and 85 ITm3 of oxygen per tonne of slag supplied. A disadvantage of injecting these high gas flow rates in the bath is that it causes significant volatilization of lead, which is found in the dust where it dilutes the zinc and gives rise to an additional treatment cost during * the extraction of the contained metals. The volatilization of lead thus reaches about 0.7 kg per lîm3 of gas injected. For example, with the above-mentioned rates, which.

V / amount to about 150 Nrn ^ of mixture of natural gas - 8 - oxygen per tonne of slag fed, the volatilization of lead reaches about 105 kg per tonne of slag fed, or $ 35 of lead supplied. It follows that the dust! i * have a Pb content which reaches approximately $ 38 and a Zn i content which reaches only approximately $ 32. To remedy this, it is advantageous to replace here also combustion energy I! 5 introduced into the nozzles by electrical energy, introduced via electrodes immersed in the slag and i connected to an alternating voltage source. At the limit, jj, all of the required energy can even be supplied i ji in electrical form and the reactor then becomes an electric oven with submerged electrodes, the Luxembourg invention patent No. 80.506 claims, however, that in this case , advantageously maintains the injection of a weak | flow of non-oxidizing gas so as to produce a mixing ξ? effective of the molten material, the flow rate of the non-oxidizing gas a Â} being preferably between 0.5 and 1.5 IIm3 / hour / ton of treated material and the nature of the non-oxidizing gas I being for example natural gas. the slag at $ 30 Pb f <and $ 10 Zn in the example above, then the injection i is limited to approximately 30 lm 3 of natural gas per tonne of slag supplied, i 'so that the volatilization of lead does not exceed:] approximately $ 10 of lead supplied and that zinciferous dust; "I have a content Zn reaching approximately $ 52 and a content Pb i q • not exceeding approximately $ 18.

traits \ · Other characteristic features of the invention which are the subject of the present patent application will clearly emerge from the following claims.

r

Claims (23)

1. A process for treating Pb-Cu-S charges containing at least one of the elements Pe, Ag, Bi, Zn and Sn, comprising the steps of (a) the iusion of the charge while maintaining conditions such that the fusion produces a slag phase, containing at least about 10 $ Pb, a copper matte phase containing less than about 65 $ Or and a lead phase, (b) the separation of the slag, copper matte and lead of work produced in stage (a), and (c) the reduction of the slag phase separated in stage (b), in the molten state by maintaining conditions such that the reduction lowers the content in lead from the slag phase at a value of less than about $ 2, and in which steps (a) and (c) are carried out in two separate reactors, this process being characterized in that at least one of these reactors is tiltable and fitted with nozzles. 2. Method according to claim 1, characterized in that step (a) is carried out in a tiltable cylindrical oven provided with nozzles and an oxidizing agent is injected through »/ * · ψ 3. Method according to claim 2, characterized in that it provides electrical energy in the tiltable cylindrical oven. 4. Method according to claim 1, characterized in that I that step (a) is carried out in a tiltable electric furnace provided with nozzles and an oxidizing agent is injected through the nozzles. 5. Method according to claim 2, 3 or 4, characterized in that an oxidizing agent and a fuel are injected through the nozzles, in proportions such that a mixture of oxidizing combustion gases is produced. 6. Method according to claim 1, characterized in that step (a) is carried out in a non-tiltable electric oven. 7. Method according to claim 6, characterized in that sulfurized materials are introduced from the top of the furnace in admixture with oxygen or an oxygen-containing gas under conditions such that these sulfurized materials are at least partially grilled before joining the liquid bath in the oven. 8. Method according to any one of claims 2 to 7> characterized in that step (c) is carried out in a tiltable cylindrical oven provided with nozzles and a fuel and an oxidant are injected through the nozzles of this oven, in proportions such that a mixture / * of non-oxidizing combustion gas is produced. GO 9. Method according to claim 8, characterized in that it provides electrical energy in the oven ‘used to perform step (c). - 10. Method according to any one of claims 2 to 7, characterized in that step (c) is carried out in a tiltable cylindrical oven provided with nozzles, electrical energy is supplied there and a gas is injected non oxidizing through the nozzles of this oven. 11. Method according to any one of claims 2 to 7, characterized in that step (c) is carried out in a tiltable electric oven provided with nozzles and a fuel and an oxidant are injected through the nozzles of this oven , in such proportions that a mixture of non-oxidizing combustion gases is produced. 12. Method according to any one of claims 2 to 7, characterized in that step (c) is carried out in a tiltable electric oven provided with nozzles and a non-oxidizing gas is injected through the nozzles of this oven. 13. Method according to any one of claims 2 to 5, characterized in that step (c) is carried out in a non-tiltable electric oven and a non-oxidizing gas is injected into the molten bath using spears. 14. Method according to any one of claims 8 to 12, characterized in that a solid reducing agent is injected through the nozzles of the oven used to perform / step (c). 15. Method according to any one of claims 8 to 13, characterized in that a solid reducing agent is introduced from the top of the oven used to carry out step (c). 16. The method of claim 10, 12 or 13, characterized in that a reducing gas is used as the non-oxidizing gas. 17. The method of claim 9 or 11, characterized in that the mixture of non-oxidizing combustion gas has a flow rate less than about 30 Nm? per tonne of slag fed to the furnace. 18. The method of claim 10, 12, 13 or 16, characterized in that the non-oxidizing or reducing gas is injected at a flow rate less than about 30 μm5 per tonne of slag fed into the furnace. 19- Method according to any one of claims 2, 3, 8, 9 or 10, characterized in that one uses as a tiltable cylindrical furnace provided with nozzles, a siphon converter. 20. Method according to any one of claims 3, 4, 6, 7, 9, 10, 11, 12 © t 13, characterized in that electrical energy is supplied by means of electrodes i. plunging into slag and connected to an alternating voltage source. 21. Method according to any one of the preceding claims *, characterized in that the dust produced in step (a) is recycled with the load. s /% 22. Method according to claim 21, characterized in that the dust produced in * step (c) is treated separately for extraction of the metals contained. „23 · Process according to any one of the preceding claims, characterized in that the lead content of the slag resulting from step (c) is between approximately $ 0.15 and approximately $ 1. r. · J. v "*)% r ·? · - r. c '; .v ....... 4 -!. .. ......... r- * ·') j c-: c:; T '! cn £ ···. *} no revcnc: cs.; ion: 3X1. description,, - ^ f-' 3 Ah ***** ♦ k