Pyrite hydrophobic flotation reagent low-odor regulation and control method and odor online monitoring system

Abstract

The invention relates to a pyrite hydrophobic flotation reagent low-odor regulation and control method which comprises the following steps: step 1, a molecular design stage, step 2, a molecular design stage, and step 3, adding a certain amount of mineral oil (or oleic acid), ethyl xanthate or butyl xanthate for molecular assembly according to hydration conditions; the method comprises the following steps: 1, carrying out flotation on pyrite to further improve the hydrophobicity of the surface of pyrite, 2, carrying out flotation on the pyrite to further improve the hydrophobicity of the surface of the pyrite, 4, taking a liquid mixture consisting of polyoxypropylene ether as a main component, alcohols, hydrocarbons and a plurality of oxygen-containing organic compounds as a foaming agent, and 5, carrying out flotation to obtain pyrite concentrate and sulfur concentrate. By means of the method, it is ensured that the concentrate yield can be ensured and the flotation operation peculiar smell can be effectively controlled through beneficiation reagent regulation and control.

Description

Technical Field

[0001] The present invention relates to a method for regulating low odor of pyrite hydrophobic flotation reagent and an on-line odor monitoring system; in particular, it is applicable to the regulation of low odor of pyrite hydrophobic flotation reagent; specifically, it relates to a method for regulating low odor of pyrite hydrophobic flotation reagent and its measuring device; it belongs to the fields of development of beneficiation reagents and monitoring of volatile organic compounds. Background Technique

[0002] The flotation reagents for pyrite mainly include collectors, inhibitors, frothers, etc.; through the hydrophobicity of minerals, the minerals adhere to the bubbles generated by the frother; at the same time, the hydrophilic minerals settle in the pulp to achieve the flotation of pyrite. Because the surface of pyrite FeS2 has oxidability, it can form dixanthogen on the surface with traditional xanthates (ethyl xanthate or butyl xanthate) to provide strong hydrophobic performance; at the same time, there is a strong chemical interaction between pyrite FeS2 and ethyl thionocarbamate, and higher sulfur-iron recovery performance can be achieved through frothers such as polyoxypropylene ether.

[0003] Because traditional xanthates have advantages such as low cost and stable beneficiation indexes in the beneficiation application of pyrite FeS2; they are widely used in wild mines at home and abroad; with the rapid development of urban construction in Nanjing, Meishan Mining is gradually surrounded by newly developed residential communities, becoming a rare urban mine in the world; xanthate flotation reagents have a strong pungent smell, and at the same time, when beneficiation reagents are used in combination with xanthates, more complex odors will be further released. Affected by factors such as temperature and pulp pH, the volatilization is faster in summer, resulting in obvious odor diffusion. Traditional xanthate flotation reagents are no longer suitable for the flotation operation of urban mines.

[0004] The Meishan iron deposit where Meishan Mining is located is in the northern section of the Ningwu volcanic rock basin in the eastern part of the middle and lower reaches of the Yangtze River metallogenic belt ( Figure 1 ), which is a typical porphyry-type iron deposit. For a long time, it has mainly produced pyrite and magnetite; the Fe grade in the feed pyrite is 38% - 45%; the S grade in the feed is about 1.2 - 1.4%; at the same time, it also contains Ti, V, Cr, Co, Ni, As and rare earth metals (La, Ce, Pr, etc.); in the research and development of new flotation reagents, it is necessary to improve the recovery rates of sulfur, iron and metals such as Co and Ni.

[0005] Based on the above background information, in the flotation operation of pyrite in the urban mine of porphyry-type iron deposit, it is necessary to regulate the beneficiation performance and low odor of flotation reagents.

[0006] At present, patents in the related technical field of ore dressing include "CN201510008891.X A Method for Flotation Separation of Limonite from Zinc Oxide Concentrate" and "CN201710624921.9 A Method for Ore Dressing of High-Sulfur Magnetite Ores Containing Pyrrhotite and Pyrite", which use butyl xanthate as a collector, No. 2 oil as a foaming agent, and oxalic acid to adjust the pH; it can produce desulfurized iron concentrate with an iron concentrate grade of TFe > 70.0% and TS < 0.3%; however, the dosage of butyl xanthate used is 500 - 600 g / t; its flotation operation will produce obvious peculiar smells; at the same time, this technology is applicable to high-sulfur magnetite, and for the application effect of pyrite with a TFe grade of 41% - 45% and a TS grade of 1.2 - 1.4% in the original ore is general. In the technical field of the peculiar smell on-line monitoring system, there is a patent "CN105651896.A A Photoionization Chromatographic Analysis Device in the Form of a Packed Column". In "CN105651896.A A Photoionization Chromatographic Analysis Device in the Form of a Packed Column", the sonic velocity flow-limiting method is used to control the flow rate. This method has low control accuracy, poor flexibility, and a relatively fixed application scenario. This device uses a packed column for separation and does not apply the method of programmed temperature rise, and it cannot analyze pollutants that may be generated during the regulation of flotation reagents such as styrene, thioether, and carbon disulfide within <10 minutes. At the same time, a six-way valve is used in this device for gas path control, and the chromatographic column cannot be backflushed, which may cause substances to remain in the chromatographic column, affecting the analysis results of the next sample and producing false positives for the regulation results.

[0007] None of the above technical solutions can solve the problem of both flotation performance and low peculiar smell in the low-peculiar-smell regulation of pyrite flotation reagents; therefore, there is an urgent need for a new solution to solve this technical problem. Therefore, there is an urgent need for a new solution to solve this technical problem. Summary of the Invention

[0008] The present invention precisely aims at the technical problems existing in the prior art, and provides a method for low-peculiar-smell regulation of pyrite hydrophobic flotation reagents and a peculiar smell on-line monitoring system. Through this solution, it is ensured that the regulation of ore dressing reagents can not only guarantee the concentrate yield but also effectively control the peculiar smell of the flotation operation.

[0009] In order to achieve the above purpose, the technical solution of the present invention is as follows. For the method for low-peculiar-smell regulation of pyrite hydrophobic flotation reagents, the specific regulation process and reagent use are as follows:

[0010] Step 1: In the molecular design stage, a certain amount of formic acid-xanthate is used to adjust the pulp to a pH of 5 - 6; at the same time, the pulp is aerated to enhance the generation of hydroxyl radicals, improve the catalytic oxidation ability of the pyrite surface; improve the chemical interaction between pyrite and xanthate-ethyl thionocarbamate; promote the reduction of electrons in the mineral surface layer to form an obvious electron reduction layer, improve the hole catalytic performance of the mineral surface, and then a certain amount of mixed solution of ethyl thionocarbamate and sodium sulfide is added.

[0011] Step 2: In the molecular design stage, within 10 - 30 minutes after adding xanthate - ethyl thionocarbamate, adjust the pH to 9 - 11 using sodium hydroxide, and add a certain amount of sodium sulfide and thiazole sodium salt collectors. Utilize the characteristic of strong hydrogen bonding to form a hydration layer of multiple water molecules on the surface of pyrite.

[0012] Step 3: According to the hydration situation, add a certain amount of mineral oil (or oleic acid), ethyl xanthate or butyl xanthate for molecular assembly; further improve the hydrophobicity of the pyrite surface.

[0013] Step 4: Use a liquid mixture mainly composed of polyoxypropylene ether, alcohols, hydrocarbons and various oxygen - containing organic compounds as the frother.

[0014] Step 5: Obtain sulfur - rich iron concentrate and sulfur concentrate through the above flotation process.

[0015] The dosage of the above - mentioned agents is as follows:

[0016] Sodium hydroxide: 600 - 800 g / t;

[0017] Sodium sulfide: 300 - 500 g / t;

[0018] Thiazole sodium salts: 60 - 120 g / t;

[0019] Polyoxypropylene ether: 50 - 100 g / t;

[0020] Butyl xanthate / ethyl xanthate: 15 - 30 g / t;

[0021] Formic acid - xanthate: 7 - 8:1, with the remaining aqueous solution; 3 - 10 L / t

[0022] Mixture of ethyl thionocarbamate and sodium sulfide: 15 - 70 g / t

[0023] Mineral oil (or oleic acid): 50 - 100 ml / t.

[0024] Linkage control of odor diffusion with agent dosage and addition sequence:

[0025] Lead out an exhaust pipe in the simulated small - scale flotation test device; use a gentle breeze device such as a fan in the exhaust pipe to enable the normal emission of odor during the flotation process, and open a sampling port in the exhaust pipe. Use an odor measurement and monitoring device to conduct on - line monitoring of the emitted odor. According to the physical and chemical properties of the agents, the monitored indicators selected for on - line monitoring are odor concentration, styrene, thioether, styrene, carbon disulfide and other odor - related indicators.

[0026] It is used for the beneficiation of pyrite with a TFe grade of 41% - 45% and a TS content of 1.2 - 1.4% in the original ore, and is used in the flotation section of beneficiation.

[0027] An online odor monitoring system, the online monitoring system includes a carrier gas system, an enrichment system, a valve control system, a photoionization detector, a chromatographic column system, a human-computer interaction system, a main board, a power supply system and a power source. Among them, the valve control system is connected to the carrier gas system, the enrichment system, the photoionization detector and the chromatographic column system at the same time, and is used to control the gas path switching of the whole instrument, so that the instrument switches between the sample injection backflush state and the measurement state, ensuring the stable operation of the instrument; the photoionization or pulsed luminescence detector is connected to the chromatographic column system, and is used to detect the compounds separated by the chromatographic column system, and its signal response is displayed in real time by the human-computer interaction system.

[0028] Among them, the carrier gas system uses electronic pressure control, is provided by an air pump or an external carrier gas, uses a metal semiconductor compound sensor for monitoring the odor concentration, and has an olfactory discrimination device at the detector outlet for smelling and measuring at the same time, and calibrates and trains and optimizes the sensor's perception of odors in a timely manner according to human olfactory perception; at the same time, a photoionization or pulsed luminescence detector is used to analyze odor components such as hydrocarbons, benzene series, carbon disulfide, and thioethers separated by the chromatographic column.

[0029] The enrichment system is used to quantitatively sample the odor components in the regulation system at normal temperature and pressure or enrich the sample at normal temperature; the odor concentration system mainly contains an adsorption tube of 1 / 8 inch or 1 / 16 inch that can be instantaneously heated and desorbed; the adsorbent installed therein is a composite bed layer composed of sulfur-modified graphitized carbon and carbon molecular sieve with >1000 g / m 3 of.

[0030] The chromatographic column system includes a chromatographic column, a heating module, a temperature measuring module and a cooling module, and is connected to the enrichment system and the photoionization detector through the valve control system. In the sample injection backflush state, the carrier gas of the carrier gas system backflushes the chromatographic column to remove the residue of the previous analysis on the chromatographic column.

[0031] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0032] 1. This technical solution uses the molecular coordination theory to redesign the flotation reagents for pyrrhotite; uses molecular design and molecular assembly techniques; reduces the dosage of butyl xanthate / ethyl xanthate in the collector by 95%; about 500 g / t; at the same time, a mixed solution of polyoxypropylene ether, alcohols, hydrocarbons, and oxygen-containing organic compounds with a lower odor is used as a foaming agent to replace No. 2 oil. The sulfur concentrate yield of 40 g / t of the mixed solution of polyoxypropylene ether, alcohols, hydrocarbons, and oxygen-containing organic compounds is equivalent to that of 80 g / t of No. 2 oil; the odor is significantly reduced.

[0033] 2. The malodorous components related to the flotation reagents detected in the online monitoring of malodor for this technical solution show that the highest detected concentration of aromatic hydrocarbons is styrene. Before the odor control of the flotation reagent, it was 45.86×10 -9 , and after the odor control of the flotation reagent, it was 12.35×10 -9 , a decrease of about 80%; among the halogenated hydrocarbons, the highest detected concentration in winter is methylene chloride. Before the odor control of the flotation reagent, it was 4.31×10 -9 , and after the odor control of the flotation reagent, it was 10.11×10 -9 , an increase of about 1.3 times; the highest detected concentration of ketones is acetone. Before the odor control of the flotation reagent, it was 23.78×10 -9 , and after the odor control of the flotation reagent, it was 13.61×10 -9 , a decrease of about 40%.

[0034] 3. The present invention does not solely change the traditional reagent formulation ratio; instead, it uses molecular design and molecular assembly technologies to target the surface molecular coordination of pyrite; at the same time, through the up and down linkage adjustment of the addition amount of the flotation reagent, the addition sequence and the total amount and components of the malodorous substances emitted during flotation; it ensures that the regulation of the ore dressing reagent can not only guarantee the concentrate yield but also effectively control the odor during the flotation operation. BRIEF DESCRIPTION OF THE DRAWINGS

[0035] Figure 1 is a schematic diagram of the overall structure of this application,

[0036] Figure 2 is a schematic diagram of the overall structure of the online monitoring system,

[0037] Figure 3 is a schematic diagram of the coordination between the flotation collector and the surface of pyrite in the present invention,

[0038] Figure 4 is a schematic diagram of the hydrophobicity after the interfacial molecular assembly of the flotation collector in the present invention. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0039] To deepen the understanding of the present invention, the following will give a detailed description of this embodiment in conjunction with the drawings.

[0040] Example: The pyrite used in the example is taken from Meishan Mining. The ore phase table is shown in the following table

[0041]

[0042] The grade of TFe is 43.77%; the grade of TS is between 1.4%; after flotation with the regulated flotation reagent, iron concentrate with a TFe grade of 56.63 and sulfur concentrate with a grade of 36.53% are obtained; the S recovery rate of the sulfur concentrate is increased by 5.28%, and the S grade of the sulfur-iron concentrate is reduced by 0.086%.

[0043] Before the regulation of flotation reagents, the collector was butyl xanthate / ethyl xanthate, and the frother was No. 2 oil; after the regulation, the collector was a mixture of butyl xanthate / ethyl xanthate - sodium sulfide - ethyl thionocarbamate - thiazole sodium salt; the frother was a mixed solution of polyoxypropylene ether, alcohols, hydrocarbons, and oxygen-containing organic compounds.

[0044] The dosage of butyl xanthate / ethyl xanthate used in the present invention is < 30 g / t, and the corresponding odor fugitive emission concentration is < 20 (dimensionless).

[0045] The on-line monitoring system used in the present invention uses a metal oxide detector and a microchannel photoionization detector to target and monitor the odor fugitive emission concentrations of mineral processing reagents such as sodium sulfide, ethyl thionocarbamate, thiazole sodium salt, and butyl xanthate, as well as odor components such as styrene, dichloromethane, acetone, and carbon disulfide under acidic or alkaline conditions. The detection limit of odor components is < 1 ppb.

[0046] Example 1: Refer to Figure 2 , the on-line monitoring system includes a carrier gas system 1, an enrichment system 2, a valve control system 3, a photoionization detector 4, a chromatographic column system 5, a man-machine interaction system 6, a main board 7, a power supply system 8, and a power supply 9. Among them, the valve control system is connected to the carrier gas system, the enrichment system, the photoionization detector, and the chromatographic column system at the same time, and is used to control the gas path switching of the entire instrument, so that the instrument switches between the injection backflush state and the measurement state, and ensures the stable operation of the instrument; the photoionization or pulsed luminescence detector is connected to the chromatographic column system and is used to detect the compounds separated by the chromatographic column system, and its signal response is displayed in real time by the 6 man-machine interaction system.

[0047] Among them, the carrier gas system uses electronic pressure control and is provided by an air pump or an external carrier gas. When using an air pump, the air pump will inhale ambient air, and the air will be purified by the device to ensure that the carrier gas does not contain impurities that affect the measurement results. When using an external carrier gas, the air pump does not work. According to needs, the electronic pressure control system controls the output pressure of the carrier gas to ensure a stable carrier gas flow rate in the gas path.

[0048] Among them, an adsorption tube is used in the enrichment system to enrich the gas sample. In the injection state, the injection pump inhales the gas sample into the enrichment system, and the pollutants are enriched on the adsorption tube; after the injection process is completed, the adsorption tube is heated to quickly desorb the enriched pollutants, which are pushed by the carrier gas into the 5 chromatographic column system.

[0049] Among them, the chromatographic column system includes a chromatographic column, a heating module, a temperature measurement module, and a cooling module, and is connected to the enrichment system and the photoionization detector through a valve control system. In the injection backflush state, the carrier gas of the carrier gas system backflushes the chromatographic column to remove the residues of the previous analysis on the chromatographic column. In the measurement state, after the carrier gas of the carrier gas system carries the sample gas concentrated by the enrichment system into the chromatographic column system, the heating module and the temperature measurement module are controlled by the instrument main board, and the chromatographic column is gradually heated according to the pre-set temperature rising method to realize the function of programmed temperature rising. Different components in the sample gas are gradually separated during the programmed temperature rising process and sequentially enter the photoionization detector to generate signal responses. After all components enter the photoionization detector, the cooling module cools the chromatographic column system to return the temperature to the initial temperature to prepare for the next measurement. Among them, the human-computer interaction system controls the normal operation of the entire instrument, and views, judges, and arranges the analysis results.

[0050] It should be noted that the above embodiments are not used to limit the protection scope of the present invention, and equivalent transformations or substitutions made on the basis of the above technical solutions all fall within the protection scope of the claims of the present invention.

Claims

1. A method for controlling the low odor of a pyrite hydrophobic flotation agent, characterized in that: The specific regulation process and the use of the drug are as follows: Step 1: In the molecular design stage, a certain amount of formic acid-xanthate is used to adjust the slurry to a pH of 5-6; at the same time, the slurry is aerated to enhance the generation of hydroxyl radicals and improve the catalytic oxidation ability of the pyrite surface; improve the chemical interaction between pyrite and xanthate-ethyl thiocyanate; promote the reduction of electrons on the mineral surface layer, form a significant electron reduction layer, and improve the catalytic performance of holes on the mineral surface, and then add a certain amount of ethyl thiocyanate and sodium sulfide mixed solution, Step 2: Molecular design stage: within 10 to 30 minutes after adding the xanthate-ethylthiocyanate mixture, use sodium hydroxide to adjust the pH to 9 to 11, and add a certain amount of sodium sulfide, thiocyanate, Sodium salt collectors use their strong hydrogen bonding properties to form a multi-layer hydration layer of water molecules on the surface of pyrite. Step 3: According to the hydration conditions, add a certain amount of mineral oil (or oleic acid), ethyl xanthate or butyl xanthate for molecular assembly; further improve the hydrophobicity of the pyrite surface, Step 4: Use a liquid mixture mainly composed of polyoxypropylene ether, alcohols, hydrocarbons and various oxygen-containing organic compounds as a foaming agent. Step 5: Through the above flotation process, floating pyrite concentrate and sulfur concentrate are obtained.

2. The method for controlling low odor of pyrite hydrophobic flotation reagent according to claim 1, characterized in that: The dosage of the drug is: Sodium hydroxide: 600-800 g / t; Sodium sulfide: 300-500g / t; Thiophanate Sodium salts: 60-120 g / t; Propylene glycol ether: 50-100 g / t; Butyl xanthate / ethyl xanthate: 15-30 g / t; Formic acid-xanthate: 7-8:1, residual aqueous solution: 3-10L / t A mixture of ethyl thiocyanate and sodium sulfide: 15~70g / t Mineral oil (or oleic acid): 50-100 ml / t.

3. The method for controlling low odor of pyrite hydrophobic flotation reagent according to claim 1, characterized in that: It is used for the beneficiation of pyrite with TFe content of 41% to 45% and TS content of 1.2 to 1.4% in the original ore, and is used in the flotation process of beneficiation.

4. An online odor monitoring system, characterized in that: Used to realize the low odor control method of pyrite hydrophobic flotation reagent according to any one of claims 1 to 3, The online monitoring system includes a carrier gas system, an enrichment system, a valve control system, a photoionization detector, a chromatographic column system, a human-computer interaction system, a mainboard, a power supply system and a power supply, wherein the valve control system is simultaneously connected to the carrier gas system, the enrichment system, the photoionization detector and the chromatographic column system, and is used to control the gas path switching of the entire instrument, so that the instrument switches between the injection backflush state and the measurement state, ensuring the smooth operation of the instrument; the photoionization or pulse luminescence detector is connected to the chromatographic column system, and is used to detect compounds separated by the chromatographic column system, and its signal response is displayed in real time by the human-computer interaction system.

5. The online odor monitoring system according to claim 4, characterized in that: The carrier gas system uses electronic pressure control and is provided by an air pump or an external carrier gas. A metal semiconductor compound sensor is used to monitor the odor concentration. There is an olfactory identification device at the detector outlet to perform testing while smelling. The sensor's perception of odor is timely calibrated and trained to optimize it based on human olfactory perception. At the same time, a photoionization or pulsed luminescence detector is used to analyze the hydrocarbons, benzene series, carbon disulfide, and sulfide odor components separated by the chromatographic column.

6. The online odor monitoring system according to claim 2, characterized in that: The enrichment system is used to perform quantitative or enrichment sampling of the odor components in the control system at room temperature and pressure; the odor concentration system mainly includes a 1 / 8 inch or 1 / 16 inch adsorption tube that can be instantly heated and desorbed; the adsorbent inside is sulfur-modified graphitized carbon, >1000g / m 3 A composite bed composed of carbon molecular sieves.

7. The online odor monitoring system according to claim 6, characterized in that: The chromatographic column system includes a chromatographic column, a heating module, a temperature measurement module and a cooling module, which are connected to the enrichment system and the photoionization detector through a valve control system. In the injection backflush state, the carrier gas of the carrier gas system backflushes the chromatographic column to remove the residues of the previous analysis in the chromatographic column.

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