SU1497250A1 - Method of bringing out arsenic from technological process - Google Patents

Abstract

The invention relates to non-ferrous metallurgy, in particular, to methods for taking the mouse out of technological processes and neutralizing it when processing mouse-containing materials. The aim of the invention is to reduce the pollution of the environment. The method involves firing raw materials, enriching arsenic-containing firing gases with oxygen to a weight ratio of total sulfur and arsenic to oxygen ≤ 0.8 at 800–900 ° C, contacting the resulting gas mixture with an iron candle in an oxidizing firing unit of iron-sulfide material at a mouse weight ratio As for the cinder ≤1: 6.2, blending of the obtained product with fluxes - calcium and silicon oxides (5-10% CAO and 15-30% SIO ₂ ), the introduction of the charge into the slag melt of the smelting furnace with the ratio charge: slag = 1: 10-15 with the subsequent sanitary processing otkh d gases. 4 hp ff, 1 tab.

Description

The invention relates to non-ferrous metallurgy, in particular, to methods for removing microscopic materials from technological processes and neutralizing them during processing of microorganisms containing materials.

The purpose of the invention is to reduce environmental pollution.

The method is carried out as follows.

Experiments on the development of this method were carried out in laboratory conditions. As the source material used:

-sulfide myc-containing concentrate composition, wt.%: Fe 28,6; Si 4.96; S 33.4; As 16.5; Sn 1.06;

pyrite concentrate, composition, wt.%: Fe 38,0; Si 5.0; S 45.0;

As 0.8;

- copper slag composition, wt.%: FeO 35.0; 5.0;

SiOj 40.0; CaO 8.0; AljOj 5.0; ZnO 3.0.

The experiments were carried out in a laboratory setup that simulates the conditions for distilling the mouse out of the melting unit under roasting-melting conditions and con,

with to

ate

3149

tact of sublimates with a sorbent in the conditions of roasting of pyrite concentrate. The installation consisted of a quartz ampoule with a lower nozzle at the bottom of which a crucible with a mouse-containing sulfide concentrate was placed, and at a height of 10–15 cm a conical crucible with a grate bottom with a pyrite concentrate placed in it. The crucible was seated on asbestos compaction so that all gases from roasting of the sample of molded material and forced blowing through the nozzle of the ampoule passed only through the sample, pyrite concentrate in the lattice crucible, creating during regulation the conditions of optimal oxidative roasting without blowing material. na Blowing, enriched with oxygen, was supplied exclusively by the gas space above the crucible with mouse sample. This achieved almost complete distillation of the mouse from the sample into sublimates in the form of sulphides or elemental (partial and P1 ,,), which in gas space were oxidized to higher oxides and flowed to the crucible with a sorbent. Excess. oxygen in the blast allowed the oxidation of the pyrite concentrate to the calcine at which the sorption of oxide was carried out. The waste gases after the crucible with the sorbent were aspirated through a system of absorption vessels with an alkaline solution and an indicator on the way to the outlet.

The reaction vial was inserted into a vertical tube furnace. Heating over the height of the ampoule was controlled and regulated by thermocouples in the area of the crucible with the sample and in the area of the crucible with the sorbent. The heating temperature of the sorbent was always ahead and reached the necessary values, after the heating zone the crucible was heated with the initial sample of the concentrate.

The introduction of the obtained sorbent containing sorbates into the slag melts was carried out in a crucible furnace, loading them in the required ratio to the slag in the prepared mixture and melting the resulting mixture in crucibles at 1250–1300 ° C and loosening 1.0–1 5h at a given temperature.

10 15 35

25

40

45 §0

55

The control of the migration of particles and its distribution between the smelting products and the exhaust gases was carried out by chemical analysis of samples of the obtained products and solutions of absorbing vessels. Analysis of mouse content was performed by standard methods.

The results of the experiments are tabulated.

Example 1. The experiment was carried out at a weight ratio of mouse to pyrite cinder, equal to 1: 6.2, temperature of sorbent (pyrite cinder) 800 C, with weight ratio of the sum of sulfur and mouse to oxygen in blast. E, equal to 0, eight. At the same time, in the cinder of the initial sample, 1.2% of the remaining mass remained, 93.8% passed into the sorbate (with a content of 13.3% in it), and 5.0% of the original was removed from the gases. Further, when smelting with slag with the addition of 10% CaO and 30% SiO (by weight of sorbate) with a ratio of the resulting mixture to slag equal to 1:10, the yield into the slag was 9.4.0%, and into the gases 4.1% mouse from asked to melt. The content of the mouse in the slag is 0.95%. The structure of the slag is homogeneous, leaching from it at the top (3 months) of the sample in water at pH 7.51-7.84 was 0.05 mg / l.

Example 2. The experiment was carried out with the weight ratio of mouse to pyrite cinder (sorbent) equal to 1: 6.6, temperature 900 ° C, with weight ratio of the total of sulfur and sulfur to oxygen in the blast equal to 0.7. At the same time, 1.3% remained in the cinder of the initial sample, 94.5% passed to the sorbent, and 4.2% of the mouse to the adsorption gases. The resulting sorbate contained 13.0% mouse.

Further, when smelting with slag (temperature 1250–1350 ° C) with the addition of 8% CaO and 20% SiO (by weight of sorbate) and with a mixture ratio to slag equal to 1:12, the yield in the mouse was 93.3%, and in: gases - 6.4% (with a ignition ratio of 0.3%) of that set for smelting. The content of the mouse in the putty is 0.90%. The structure of the slag is homogeneous, the washing out of it when exposed to water (3 months) at pH 7.23-7.73 was 0.05 mg / l.

Example 3. The experiment was carried out with the weight ratio of pulp to pyrite calcine (sorbent) equal to 1: 6.6, temperature 900 C, with the weight BOM the ratio of the sum of mouse and sulfur to oxygen in the blast equal to 0.8. At the same time, 1.5% remained in the cinder of the initial sample, 94.0% passed to the sorbent, and 4.5% of the mouse went to the gases after sorption. The resulting sorbate contained 12.8% m Further, when smelting sorbate with slag (at 1250-1350 ° С) with the addition of 10% CaO and 25% SiOj. (by weight of sorbate) and with the mixture ratio to pshak equal to 1:15, the yield to the slag mouse was 95.6% and to gases — 3.7% (with a breakdown of 0.7%) of the melting specified when it in the slag 0.81%. The structure of the slag is homogeneous, the leaching of the mouse from it at a peak of 2.5 May, water with a pH of 7.53-7.81 was 0.05 mg / l

„,,„ ...,., „,„ „..„, „...,„.

(at T: F 1:10 and free access

air).

Example 4. The experiment was carried out with the following parameters: the ratio of mass to pyrite calcine (sorbent) 1: 6.6, temperature 900 C, weight ratio of mass and sulfur to oxygen in the blast 0.8. At the same time, in the initial sample, the remaining sample was 1.8%, 94.7% passed to the sorbent, and 3.5% of the milk was transferred to the sorbent after sorption. The resulting sorbate contains 13.3%.

When smelting sorbate with slag with parameters: temperature 1250-1350 C, addition of 10% CaO and 25% SiO (to the weight of sorbate), the ratio of mixture to slag is 1:16, the exit to the slag mouse was 96.0%, and to gases - 3.5% (at a failure rate of 0.5%). The mouse content in the slag in this experiment dropped to 0.68%. The structure and results of leaching are similar to examples 1-3.

Example 5. Conditions of experience:

40 increase in gases after sorption (9.5%), as well as a decrease in the transfer of mice to slag (89.5%) and an increase in its loss with gases (10.3%). The first is due to the beginning of the partial

ratio of pyptic to pyrite

the calcine (sorbent) is 1: 5.9, the temperature is 45 ″ ani of the sorbate material, and the second is thickening of the slag at a temperature of 1250–1350 ° C, which leads to a non-uniform viscous structure of the slag and

(to the deterioration of the dissolution of the mouse in it 92, 2%, and in the gases after sorption - 6.6% of the 50th coke phase.

bit from the initial content. Example 9. The conditions of the experiment differ in the reduction of the oxygen supply to the blast (the ratio of the sum of sulfur and mouse to oxygen is 0.9). This leads to a decrease in the capture of the mouse on the sorbent (80.5%) due to incomplete oxidation of the components involved in the reaction (mouse oxide + iron oxides).

900 C, the weight ratio of the amount of sulfur and mya to oxygen in the blast is 0.8. At the same time, in the butt end of the original sample, 1.2% remained,

The content of mice in sorbate was 13.5%.

When smelting sorbate with slag with parameters: temperature 1 250-1 З50 s, additives 10% CaO and 30% 510 (to the weight of sorbate), the ratio of mixture to slag 1:12, the exit into the slag mouse was

93.6% 5 a in gases 6.1% (with a balance of 0.3%). The content of the mouse in the slag is equal to 0.86%. The structure of the slag and the results of leaching are similar to experiments 1-4.

In the experiment, while reducing the amount of pyrite calcine (1: 5.9 ratio), there is a decrease in trapping

mouse to sorbate (92.2%) and an increase in its loss in gases (6.6%).

Example 6. Experimental conditions: mouse to pyrite calcine ratio of 1: 5.5 and blend of sorbate to slag 1: P.

As a result, there is a decrease in the distribution of pulp into sorbate (90.6%), an increase in gases after sorption (7.9%), as well as a decrease in the transfer of pulp into slag (88.8%) and an increase in

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Example 7. The conditions of the experiment are different from those of examples 1-3 by a decrease in the sorption temperature (750 ° C), which leads to a decrease in the transition

25 min to sorbate (90.2%) and an increased transition to gases (6.2%), as well as to the remaining residue in the cinder of the initial sample (3.6%). This is due to the lowering of the interaction of oxides of iron and arsenic with the formation of stable phases, as well as a slight decrease in the distillation of the mouse from the sample material.

Example 8. Experimental conditions

, g are characterized by a higher sorption temperature (950 ° C) and higher subsoil CaO and SiO (15 and 35%, respectively), which led to a decrease in the recovery of the mouse into the sorbent (89.7%)

40 increase in gases after sorption (9.5%), as well as a decrease in the transfer of mice to slag (89.5%) and an increase in its loss with gases (10.3%). The first is due to the beginning of the partial

Example 10 Experimental conditions are characterized by a reduction in the charge of CaO and SiO to the lower limit (5 and 15%, respectively). The results show that this change does not impair the data on the removal of the mouse into the sorbent (95.1%) and its transfer to the slag (95.5%).

EXAMPLE 11 Experimental conditions are characterized by a decrease in the charge of slag-forming CaO and SiO below the lower limit (3 and 10%, respectively). The results show that in this case, although the distribution in the donkey mouse is relatively high (94.8%) ,. and in the smelting gases without impingement (5.2%), the structure of the slag is not homogeneous, and inhomogeneous inclusions are visible in the collar, which are formed due to the pressure of the jerk phase. At the same time, an increase in vyivani mouse from pshak with vyderzkke (2.5 ms. In water with rp 7,, 69), which reached 0 | 063 mg / l.

The results of the experiments are shown in the table.

To estimate the optimal conditions, the total extraction of the mouse is calculated, which depends on the stages of sorption of it from the gas phase and melting - the introduction of sorbate into the molten slag. Sorption extraction of microsols depends on temperature, oxidizer consumption and amount of sorbent. At a temperature of 800 ° C (Example 7) and .900 s (Example 8), extraction of liquid is equal, and at an optimum sorption temperature of 800–900 ° C, it is 94–95%.

Sorption depends on the consumption of oxidizing agent for the formation of peroxide. When the ratio of the sum of As, S to oxygen is 0.6 (Example 10), the recovery of As is 95%, and at 0.9 (Example 9), the recovery falls to 80.5%. The optimal ratio of glAs, S to oxygen g: 0.8. Excess oxygen consumption can be limited only for economic reasons.

The amount of pyrite cinder determines the capacitance factor of the sorbent. With a mouse to pyrite ratio

ten

15

20

25

14972508

The ratio of solid to sorbent is 61: 6.2. During smelting, the amount of slag-forming agents CaO i 5% and SiO leads to insufficient bonding and formation of heterogeneous slag (Example 11) and, conversely, with a large excess, when CaO is 15% and SiO, 35% (Example 8), the extraction As falls. The optimal amounts of slag-forming additives are CaO 10% and SiO 15-30% by weight of sorbate.

Optrmal ratio of the charge - slag should be equal to 1; (10-15). As the amount of slag decreases (1: 9 ratio), the recovery of As is 88.8% (Example 6). At a ratio of 1: () it increases to 96%. The upper limit of slag consumption can be not limited, since with its increase the dilution of the mouse increases, but at the same time there is an additional dilution of the As product.

In the experiments performed, the worst results were obtained in examples 11 and .7 — formation of heterogeneous slag, 9 and 6 — low As recovery at the stages of sorption and smelting, 8 and 5 — insufficient total extraction of As.

The best results were achieved in examples 4 and 10, where the total mouse recovery is 91%.

These data confirm the correctness of the choice of optimal conditions for carrying out the extraction of a cynological process with its simultaneous obzorivaniem.

The technical advantages of the proposed invention in comparison with the known are the completeness of sorption of all volatile compounds of the mouse, regardless of its valence, the translation of the mass into a non-toxic form suitable for storage.

Claims (4)

Invention Formula 1, Method of removing a mouse from a technological process in a non-toxic form, including firing the original materials 35 40 45 50 cinder less than 6.2 (examples 5-6) extracts, sorption of arsenic compounds As does not exceed 90.6-92.2%, and with an increase in the amount of sorbent to 6.2-6.6, recovery reaches 94.0-: 94.7% (examples 3-4). Optimal from the gas phase on metal oxides, such as iron, followed by gas sanitization, characterized in that from the gas phase on metal oxides, such as iron, followed by gas sanitization, characterized in that reducing environmental pollution, mouse-containing burning gases enrich with oxygen to a mass ratio of the amount of sulfur and mouse to oxygen, 8, contact the resulting gas mixture with an iron candle and the resulting product is introduced into the slag melt, 2. The method according to claim 1, about tl and h a yu shch and PS in that the enrichment of acid -. lead to a lead at 800-900 0, 3. The method according to claim 1, which differs from the fact that the mass ratio Sewing the mouse coming in with the gas mixture to the candle end is maintained at 1: 6.2. 4. Method POP.1, characterized in that the obtained product is fed with fluxes of calcium and silicon oxides at a ratio of 5-10% CaO and 15-30% SiO, before being introduced into the slag melt. 5, the method according to claims 1 to 4, characterized in that the resulting mixture is introduced into the slag melt at a ratio of charge to slag 1: (10-15).