CN-121972279-A - Quality improving and sorting method for enhancing dissociation-re-floatation of middling grinding of washed coal

Abstract

The invention discloses a upgrading and sorting method for strengthening ore grinding dissociation-re-flotation of middling coal, which comprises the steps of adding water into middling coal to obtain slurry, and then adding a composite dissociation promoter to conduct ore grinding dissociation treatment, wherein the composite dissociation promoter comprises an anionic surfactant, a dispersing agent and a regulator. The invention obviously reduces the surface tension of the ore pulp entering into the ore grinding and ensures that the ore pulp is easier to permeate into micro cracks and a combined interface of coal and gangue, effectively reduces the interface energy and promotes the crushing effect to occur along the coal gangue interface preferentially, simultaneously, the separation of the gangue from the surface of the coal particles can be further enhanced by the stripping effect of the dispersing agent in the compound dissociation promoter, and in addition, the regulator in the compound dissociation promoter can realize the efficient dissociation of the washed coal under the cooperation of mechanical force of the ore grinding and destroy the compact symbiotic structure between the coal and gangue minerals in the ore pulp and ensure that the coal monomer and the mineral monomer are separated.

Inventors

• DENG HUIXIAN
• FU JIANGANG
• LAN QIANG
• ZHU RENFENG
• LI KERONG
• LI XINYUAN

Assignees

• 重庆长能环境科技集团有限公司

Dates

Publication Date

20260505

Application Date

20260325

Claims (9)

1. 1. A quality improving and sorting method for strengthening the grinding dissociation-re-floatation of middling coal is characterized in that water with a formula amount is added into middling coal to obtain slurry, and then a composite dissociation promoter is added into the slurry to carry out grinding dissociation treatment.
2. 2. The enhanced middling grinding dissociation-refloating upgrading process of claim 1, wherein said complex dissociation-promoting agent comprises an anionic surfactant, a dispersant and a conditioning agent.
3. 3. The method for upgrading and sorting by enhanced middling grinding dissociation-remittance according to claim 2, wherein the anionic surfactant is at least one of sodium dodecyl sulfonate, sodium dodecyl benzene sulfonate and sodium dodecyl sulfate, the dispersant is at least one of sodium carbonate, sodium hexametaphosphate and sodium pyrophosphate, and the regulator is at least one of sodium hydroxide and potassium hydroxide.
4. 4. The upgrading and sorting method for the dissociation-remittance of the intensive middling coal grinding according to claim 3, wherein the mass ratio of the anionic surfactant to the dispersant to the regulator is (1-100): 600.
5. 5. The upgrading and sorting method for enhancing the separation and re-flotation of middling grinding of middling coal, which is characterized in that the solid content of middling coal in slurry is 80-400g/L, and the dosage of the composite dissociation promoter is 200-1000 g/t.
6. 6. The method for upgrading and sorting by intensified ore-grinding dissociation-refloating of washed middling according to claim 1, further comprising performing flotation separation on the washed middling after the ore-grinding dissociation treatment.
7. 7. The upgrading and sorting method for enhanced middling grinding dissociation-re-floatation according to claim 6, wherein the amount of collector used in the floatation separation process is 3000-6000g/t, preferably 4000-5000 g/t, the amount of foaming agent used is 600-2000g/t, preferably 1000-1500 g/t, and the amount of inhibitor used is less than or equal to 2000g/t, preferably 100-1000 g/t.
8. 8. The enhanced middling grinding dissociation-remittance upgrading process as recited in claim 7, wherein said collector is at least one of white oil, shale oil and wash oil, said foaming agent is sec-octanol, and said inhibitor is water glass.
9. 9. The upgrading and sorting method for enhanced middling grinding dissociation-re-floatation of claim 8, wherein the specific floatation is 1 roughing time, 1-2 scavenging times and 1-3 selecting times.

Description

Quality improving and sorting method for enhancing dissociation-re-floatation of middling grinding of washed coal Technical Field The invention belongs to the technical field of coal flotation, and particularly relates to a quality improving and sorting method for enhancing dissociation-re-flotation of coal grinding in washing. Background In recent years, the middling coal (including part of slime) of the main coking coal preparation plants in China is almost completely sold directly or used as power plant fuel, especially in some middle and small coal preparation plants in coal-rich areas, the middling coal and slime are not sold smoothly due to the immature production technology of the middling coal preparation plants, and are abandoned in a large amount, so that the environmental pressure of mining areas is increased, and great waste is caused to the scarce coal types. Meanwhile, air pollution caused by high-ash coal combustion brings more environmental and social problems, and brings great importance to the nation. Therefore, the washed middling coal is further deeply processed to obtain low-ash clean coal, a high-efficiency and reasonable separation process is sought, and the method has profound significance on reasonable utilization of coal resources and environmental protection in China. The recleaning of the middling coal is an important way for improving the yield of the clean coal, so that the development and research of an efficient separation method have important practical significance for promoting the full recovery and the value-added utilization of the middling coal. By adopting the conventional flotation method, as the dissociation depth of the coal in the washing is insufficient, a large amount of gangue in the dissociated material still has a negative influence on the flotation process, so that the ash content and the yield of the clean coal can not reach the expected targets. Disclosure of Invention The present invention aims to solve at least one of the technical problems in the related art to some extent. Therefore, the main purpose of the invention is to provide a quality improving and sorting method for strengthening the grinding dissociation-re-floatation of coal in washing, aiming at fully dissociating the coal in washing, reducing the ash content of the clean coal and improving the recovery rate of the clean coal. The invention aims at realizing the following technical scheme: A quality-improving separation method for strengthening the grinding dissociation-re-floatation of coal in washing is to add water in a formula amount into the coal in washing to obtain slurry, and then add a composite dissociation promoter to carry out grinding dissociation treatment. The ash minerals in the washed coal are mainly clay minerals, the chemical components of the ash minerals are mainly SiO 2、Al2O3 and H 2 O, the clay minerals are generally extremely fine in particles and are most fine scale-shaped with the particle size smaller than 0.01mm and are embedded in the coal, and the ash minerals are difficult to separate and sort. In certain embodiments, the slurrying time is 2 to 60 minutes, more preferably 5 to 15 minutes. In certain embodiments, the complex dissociation promoter includes an anionic surfactant, a dispersant, and a conditioning agent. The composite dissociation promoter carries out ore grinding dissociation treatment on the washed coal, is beneficial to high-efficiency and high-selectivity separation of ash and coal, is beneficial to improving the yield of clean coal and is beneficial to reducing the ash content in the clean coal. In some specific embodiments, the anionic surfactant is at least one of sodium dodecyl sulfonate, sodium dodecyl benzene sulfonate and sodium dodecyl sulfate, the dispersing agent is at least one of sodium carbonate, sodium hexametaphosphate and sodium pyrophosphate, and the regulator is at least one of sodium hydroxide and potassium hydroxide. In some embodiments, the mass ratio of the anionic surfactant, the dispersing agent and the regulator is (1-100): 600. Further, the mass ratio of the anionic surfactant to the dispersant to the regulator is (10-50): 600. In some specific embodiments, the solid content of the middling coal in the slurry is 80-400g/L, and the dosage of the composite dissociation promoter is 600-700 g/t (the dosage of the composite dissociation promoter for each ton of middling coal dry material is 1-2 kg). Further, the solid content of the middling coal in the slurry is 200-350g/L, and the dosage of the composite dissociation promoter is 200-1000 g/t. In certain embodiments, the time for the milling dissociation is 10-30min, more preferably 15-20min. In certain embodiments, the method further comprises subjecting the washed middlings after the grinding dissociation treatment to flotation separation. According to the invention, the grinding dissociation effect is improved by the composite dissociation promoter, so that the subsequent