阅读说明：本技术 一种无酸无铵浮选被石灰抑制的黄铁矿的方法 (Method for floating pyrite inhibited by lime in acid-free and ammonium-free manner ) 是由 朱恩领 简成卫 李敏 罗文成 何爱婷 王丞 曹东江 陈昌才 于 2021-08-09 设计创作，主要内容包括：一种无酸无铵浮选被石灰抑制的黄铁矿的方法,涉及矿物加工技术领域,其方法包括以下步骤：步骤一、调浆：将待处理的含被石灰强烈抑制的黄铁矿的物料进行调浆；步骤二、重选：调浆后进行重选处理,得到重选尾矿和重选精矿；步骤三、加表面活性剂：重选精矿中加入表面活性剂行调浆搅拌至充分作用；步骤四、浮选：充分作用后的物料输送至浮选机中并加入浮选捕收剂进行充气浮选,得到浮选硫精矿及浮选尾矿。本发明的有益效果在于：处理成本和和设备配置要求远低于使用硫酸法活化被石灰强烈抑制的黄铁矿活化方法,且水体中没有氨氮污染因子,具有广泛的应用前景。(A method for floatation of pyrite inhibited by lime without acid and ammonium relates to the technical field of mineral processing, and comprises the following steps: step one, size mixing: mixing the materials to be treated, which contain pyrite strongly inhibited by lime; step two, reselection: after size mixing, carrying out reselection treatment to obtain reselection tailings and reselection concentrate; step three, adding a surfactant: adding a surfactant into the gravity concentrate for pulp mixing and stirring until the mixture fully acts; step four, flotation: and (4) conveying the fully acted materials to a flotation machine, and adding a flotation collecting agent for air flotation to obtain flotation sulfur concentrate and flotation tailings. The invention has the beneficial effects that: the treatment cost and the equipment configuration requirement are far lower than those of a pyrite activation method in which the activation is strongly inhibited by lime by using a sulfuric acid method, and the water body does not contain ammonia nitrogen pollution factors, so that the method has a wide application prospect.)

1. A method for floatation of pyrite inhibited by lime without acid and ammonium is characterized by comprising the following steps: the method comprises the following steps:

step one, size mixing: mixing the materials to be treated, which contain pyrite strongly inhibited by lime;

step two, reselection: after size mixing, carrying out reselection treatment to obtain reselection tailings and reselection concentrate;

step three, adding a surfactant: adding a surfactant into the gravity concentrate for pulp mixing and stirring until the mixture fully acts;

step four, flotation: and (4) conveying the fully acted materials to a flotation machine, and adding a flotation collecting agent for air flotation to obtain flotation sulfur concentrate and flotation tailings.

2. The process according to claim 1, characterized by the fact that the flotation of pyrite, inhibited by lime, is carried out without acid and ammonium: the surfactant is sodium hexadecyl benzene sulfate.

3. The process according to claim 1, characterized by the fact that the flotation of pyrite, inhibited by lime, is carried out without acid and ammonium: the flotation collector is amyl potassium xanthate.

4. The process according to claim 1, characterized by the fact that the flotation of pyrite, inhibited by lime, is carried out without acid and ammonium: the equipment for gravity treatment is one of a hydrocyclone and a spiral chute.

5. The process according to claim 1, characterized by the fact that the flotation of pyrite, inhibited by lime, is carried out without acid and ammonium: the mass concentration of the materials containing pyrite which is strongly inhibited by lime is 15-20%; the mass concentration of the gravity concentrate is 33-45%.

6. The process according to claim 1, characterized by the fact that the flotation of pyrite, inhibited by lime, is carried out without acid and ammonium: the mass concentration of the gravity tailings is 5-10%.

7. A method of acid-free and ammonium-free flotation of pyrite inhibited by lime according to claim 1 or 2, characterized by: the mass concentration of the surfactant is 1-5%.

8. The process according to claim 1, characterized by the fact that the flotation of pyrite, inhibited by lime, is carried out without acid and ammonium: the flotation operation comprises 1 roughing, 1-2 concentrating and 1-2 scavenging operations, wherein a surfactant and a flotation collector are added in the roughing operation, and the flotation collector is added in the scavenging operation: 10 g/t-25 g/t of hexadecyl benzene sodium sulfonate is added in the roughing, 100 g/t-200 g/t of amyl potassium xanthate is added, and 50 g/t-100 g/t of amyl potassium xanthate is added in the scavenging.

Technical Field

The invention relates to the technical field of mineral processing, in particular to a method for floating pyrite inhibited by lime in an acid-free and ammonium-free manner.

Background

At present, the most common method for activating pyrite strongly inhibited by lime used at home and abroad is a dilute sulfuric acid method, namely concentrated sulfuric acid prepared by industrial sulfuric acid plants is diluted by clear water to be prepared into a strong acid solution to adjust the pH value of copper-zinc tailing pulp, so as to achieve the purpose of activating sulfur under the condition of neutral or weak acid pulp, but the sulfuric acid has high corrosivity and high transportation and preparation risks, and a high-standard acid storage tank needs to be arranged, so the method is bound to be replaced by other methods, in addition, ammonium bicarbonate, ammonium sulfate, ammonium sulfide and the like are used as activating agents of pyrite strongly inhibited by lime, the activating agents have the advantages of wide sources, low preparation cost and the like, the activation of pyrite can be realized under the alkaline condition (the pH is more than or equal to 9), the core mechanism is that NH4+ can precipitate Ca2+ in the pulp, a hydrophilic film on the surface of the pyrite is desorbed, the hydrophilic film in the pulp is dispersed, and the like, at present, part of domestic mines adopt ammonium salt as an activating agent of pyrite in sulfide tailings, the pyrite in the tailings can be effectively activated, but the ammonium salt has the defects of large using amount which is more than 3 kg/ton of raw ore for a long time, unsafe hidden danger and the like caused by large pungent smell and medicament preparation operation, and simultaneously the ammonium salt is used as a source of ammonia nitrogen in mineral processing wastewater, free ammonia ions and ammonia nitrogen substances which influence the environmental ecology are easily generated after complex physicochemical reaction in an ore pulp solution, so that low-concentration ammonia nitrogen polluted water is formed, and the harm of the polluted water is mainly caused by the problem that a water body presents eutrophication and has adverse influence on the growth of organisms in the water.

Patent CN201910284527.4 also describes a method for activating pyrite strongly inhibited by lime by using carbon dioxide gas instead of sulfuric acid, which has certain advantages in environmental protection, but is limited by the storage and transportation limitations of canned carbon dioxide gas, and is difficult to be widely popularized. The patent CN202110277857.8 provides an activation method of pyrite inhibited by calcium oxide, the method adopts a multi-stage activation mode of ferrous sulfate, citric acid and copper sulfate to carry out multi-stage activation, the number of activation sections is more, and meanwhile, the copper sulfate is heavy metal salt, so that the potential hazard of environmental protection on flotation wastewater is avoided.

In addition, with the current great improvement of domestic mine resource utilization rate, the original mine containing partial metal sulfide and non-metal ore species gradually pays attention to the recovery of other types of non-metal minerals of copper-lead-zinc sulfide ore flotation tailings, the non-metal mineral species comprise fluorite, barite, feldspar, calcite and the like, before the non-metal minerals are recovered, pyrite in the metal sulfide ore flotation tailings needs to be removed completely through other modes, currently, most domestic metal sulfide ores containing pyrite generally adopt high alkali to inhibit the flotation activity of pyrite, and the separation of copper, lead, zinc, antimony and the like from pyrite is realized, so that the pyrite in the sulfide flotation tailings is mostly pyrite which is strongly inhibited by lime, and the conventional acid method or ammonium salt activation method has the defects of strong corrosivity, large dosage and the like, and is not beneficial to the subsequent fluorite, large dosage and the like, Flotation of non-metal minerals such as barite and the like.

Therefore, in order to further improve the resource utilization rate of the polymetallic mine and realize the activated flotation of the pyrite with low cost and excellent environment, it is necessary to develop a method for the pyrite of which the acid-free and ammonium-free flotation is strongly inhibited by the lime.

Disclosure of Invention

Aiming at the defects of the prior art, the invention aims to provide a method for floating pyrite inhibited by lime in an acid-free and ammonium-free activation flotation mode, improve the floating activity of the inhibited pyrite and overcome the adverse effects of the traditional acid method and the ammonium salt activation method on environmental protection and production safety.

The invention provides a method for floating pyrite inhibited by lime in an acid-free and ammonium-free manner, which comprises the following steps:

the method comprises the following steps: stirring and size mixing the material to be treated containing the pyrite strongly inhibited by the lime, adding clear water or thickening and size mixing until the mass concentration of ore pulp is 15-20%, obtaining the material to be treated, if the concentration of the raw material is more than 20%, reducing the concentration of the ore pulp by adding clear water with verified mass, if the concentration of the raw material is less than 15%, thickening the material by a thickener, and controlling a thickening parameter to obtain a thickening underflow with the mass concentration of 15-20% for standby application, wherein a thickening overflow part is used as gravity separation operation washing water in the second step; the pH value of the ore pulp is about 10-12 because acid and ammonium salt are not added into the material to be treated, and the ore pulp solution is still alkaline even if a certain amount of clear water is added;

step two: conveying the material to be treated to gravity separation equipment through a pump for gravity separation treatment to obtain gravity separation concentrate and gravity separation tailings, discarding the gravity separation tailings, and reserving the gravity separation concentrate for use;

the gravity separation equipment can adopt one of a hydrocyclone or a spiral chute, when the hydrocyclone is used for processing the materials to be processed, the pressure of the hydrocyclone is regulated and controlled to control centrifugal force so that light argillaceous substances and pyrite minerals in the materials to be separated are separated, the underflow part of the hydrocyclone is gravity separation concentrate products, the overflow part of the hydrocyclone is gravity separation tailing products, and when the spiral chute is used as the gravity separation equipment, the feeding rate is regulated and the yield of gravity separation concentrate and tailings is controlled;

in the second step, the metal mineral composed of the main minerals of the materials is pyrite, the gangue mineral is mainly silicate or aluminosilicate minerals such as quartz, mica and the like, and the specific gravity of the pyrite is larger than that of the gangue mineral, so that the pyrite in the materials mainly enters gravity concentration ore in gravity separation operation to achieve the effect of pre-enrichment;

in the second step, the hydrocyclone or the spiral chute of the gravity separation equipment desorbs the hydrophilic membrane adsorbed on the surface of the pyrite under the action of centrifugal force, and then the hydrophilic membrane enters the solution to form free Ca²⁺The partial desorbed calcium ions enter gravity tailing pulp under centrifugal operation, the tailing pulp is directly discarded, and pyrite strongly inhibited by lime is reduced in the second stepEffect of surface hydrophilic properties;

step three: conveying the gravity concentrate produced in the second step to a pulp mixing stirring barrel through a pump for pulp mixing and stirring, and simultaneously adding a surfactant sodium hexadecylbenzene sulfonate solution to enable the reagent to fully act with the pyrite in the gravity concentrate;

in the third step, the concentration of the added sodium hexadecylbenzene sulfate is 1 to 5 percent by mass, the addition amount is 15 to 25g/t, and the time for mixing and stirring is 2 to 5 min;

in step three, the effect of the sodium hexadecyl benzene sulfate is as follows: using the hardness water resistance of sodium hexadecylbenzene sulfonate, free Ca in concentrate solution is reselected after reselection²⁺The concentration is still higher), the surfactant still has better collecting capability, and the main functional group R-O-SO thereof₃Na and sulfur atoms on the surface of the pyrite are subjected to affinity adsorption, so that the surface of the pyrite which is strongly inhibited by lime is converted from hydrophilicity to hydrophobicity, and the conversion is an irreversible process, thereby laying a foundation for subsequent flotation;

step four: conveying the material which has the full effect of size mixing and stirring in the third step into a flotation machine through a pump, adding amyl potassium xanthate serving as a collecting agent of pyrite, performing air agitation flotation in the flotation machine to obtain flotation sulfur concentrate and flotation tailings, wherein the main mineral component in the flotation sulfur concentrate is pyrite, and the main mineral component in the tailings at the bottom of the tank is other gangue or non-metallic minerals;

in the fourth step, no additional foaming agent is added, as the sodium hexadecyl benzene sulfate has foamability, a stable foam layer can be formed under the condition of inflation, as the surface hydrophobicity of the mineral is greatly increased after the sodium hexadecyl sulfonate reacts with the surface of the pyrite, the amyl potassium xanthate is added, and the amyl potassium xanthate further reacts with the pyrite to capture, so that the pyrite is activated and floated;

in step four, the flotation operation includes 1 roughing, 1 ~ 2 choice, 1 ~ 2 scavenging operation, adds surfactant active and flotation collector in the roughing operation, adds the flotation collector in the scavenging operation, and the medicament addition is: the crude selection is added with 100 g/t-200 g/t of amyl potassium xanthate, and the scavenging is added with 50 g/t-100 g/t of amyl potassium xanthate.

The invention has the beneficial effects that: dilute acid or ammonium salt is not required to be added, so that the influence of ammonium salt addition on mine water ammonia ions and ammonia nitrogen substances is eliminated from the source, and meanwhile, the floatability of the pyrite in the ore pulp is improved; the sodium hexadecyl benzene sulfate surfactant has wide industrial application, low price and easy hydrolysis under the long-term illumination condition, compared with other surfactants, the sodium hexadecyl benzene sulfate has good hard water resistance, has higher solubility in an alkaline water body, is beneficial to subsequent hydrophobic activation, can meet the floating requirement by adopting common amyl potassium xanthate, and simultaneously has foamability to reduce the types of added pyrite flotation reagents, and is beneficial to reducing the pollutant content and types of mine wastewater; the treatment cost and equipment configuration requirements of the process provided by the invention are far lower than those of a pyrite activation method in which activation is strongly inhibited by lime by using a sulfuric acid method, and the water body does not contain ammonia nitrogen pollution factors, so that the process has a wide application prospect.

Drawings

FIG. 1 is a process flow diagram of an embodiment of the present invention.

Detailed Description

Example 1

The invention provides a method for floatation of pyrite restrained by lime without acid and ammonium, which adopts zinc tailings containing pyrite strongly restrained by lime, wherein the concentration of ore pulp is 35%; the zinc tailings are treated according to the process flow shown in fig. 1, and the treatment steps comprise:

the first step is as follows: conveying the zinc tailings into a stirring barrel, and adding clear water to adjust the slurry to a mass concentration of 15%;

the second step is that: conveying the ore pulp into a hydrocyclone for gravity separation by a pump, performing graded overflow to obtain gravity tailings and gravity concentrate, and conveying the gravity concentrate part into a pulp mixing stirring barrel;

the third step: adding 15g/t of sodium hexadecylbenzene sulfate into a size mixing stirring barrel, stirring, and then automatically flowing into a flotation machine;

the fourth step: the flotation operation of the flotation machine is rough and fine, 100g/t of amyl potassium xanthate is added into a rough flotation tank, 50g/t of amyl potassium xanthate is added into the scavenging operation, and flotation is carried out to produce flotation sulfur concentrate and flotation sulfur tailings.

The indices obtained using the process flow shown in FIG. 1 are shown in Table 1.

TABLE 1 Zinc tailings flotation gain index

Product name	Yield/%)	S grade/%	S job recovery/%)
				Gravity separation of tailings	15.50	8.40	9.53
Sulphur concentrate	25.24	48.20	89.08
				Sulfur tailings	59.26	0.32	1.39
Zinc tailings	100.00	13.66	100.00

The obtained sulfur concentrate contains 48.20 percent of S, the operation recovery rate of S is 89.08 percent, and the activated flotation effect is good.

Example 2

The invention provides a method for floating pyrite inhibited by lime in an acid-free and ammonium-free manner, which adopts copper-zinc tailings containing pyrite strongly inhibited by lime, wherein the concentration of ore pulp is 10%, and the copper-zinc tailings are treated according to the process flow shown in figure 1, wherein the treatment steps comprise:

the first step is as follows: conveying the copper-zinc tailings into a stirring barrel, and thickening the copper-zinc tailings by using a thickener until the concentration of ore pulp is 20%;

the second step is that: conveying the dense underflow part into a spiral chute for gravity separation to obtain gravity concentrate and gravity tailings;

the third step: conveying the gravity concentrate to a pulp mixing stirring barrel through a pump, and adding 20g/t of sodium hexadecylbenzene sulfate;

the fourth step: and conveying the pulp after size mixing to a flotation machine for desulfurization flotation operation, adding 200g/t of amyl potassium xanthate into roughing, adding 100g/t of amyl potassium xanthate into scavenging, and obtaining sulfur concentrate after the roughing concentrate is carefully selected, wherein scavenging tailings are sulfur tailings.

The beneficiation indicators obtained using the process flow shown in fig. 1 are shown in table 2.

TABLE 2 flotation of copper-zinc tailings

Product name	Yield/%)	S grade/%	S job recovery/%)
				Gravity separation of tailings	12.13	6.40	10.44
Sulphur concentrate	13.43	48.40	87.36
				Sulfur tailings	74.44	0.22	2.20
Zinc tailings	100.00	7.44	100.00

The sulfur concentrate obtained contained 48.40% and the operational recovery of sulfur concentrate S was 87.36%.

From the results of the embodiment, the sulfur concentrate obtained by the method has high grade, is similar to the beneficiation index of the sulfur concentrate obtained by a dilute acid method or an ammonium salt method, does not additionally add other influence factors which can cause environmental pollution, and can be popularized and used.

The foregoing examples are set forth to illustrate the present invention more clearly and are not to be construed as limiting the scope of the invention, which is defined in the appended claims to which the invention pertains, as modified in all equivalent forms, by those skilled in the art after reading the present invention.