Method for preparing coal mine filling paste by utilizing waste concrete

Abstract

The invention discloses a method for preparing a coal mine filling paste by utilizing waste concrete, and belongs to the technical field of cementation filling materials. The method comprises the steps: crushing the waste concrete and coal gangue, sieving, and allowing to become a powder having the particle size smaller than 1 mm, a fine aggregate with the particle size of 1-5 mm and a coarse aggregate with the particle size of 5-15 mm; then adding an admixture, raw lime and a gypsum solid into the powder with the particle size of less than 1 mm, stirring uniformly, then carrying out ball milling, and thus obtaining an ultrafine powder with the specific surface area of greater than or equal to 300 m<2> / kg; and finally, mixing and stirring cement, the fine aggregate, the coarse aggregate, the ultrafine powder, a conditioning agent and water to obtain the coal mine filling paste. The waste concrete is fully recycled under a condition without calcination, and thus the problems of land occupation and ecological environment destruction are solved, besides, more adequate cheap raw materials are provided for coal mine filling and mining, the filling cost is reduced, and a foundation is laid for full implementation of a filling and mining technology.

Description

technical field

[0001] The invention relates to a method for preparing coal mine filling paste by using waste concrete, and belongs to the technical field of cemented filling materials. Background technique

[0002] my country is a big country of coal production and consumption. The annual coal production and consumption amount to 100 million tons. Coal accounts for more than 70% of my country's total energy structure. However, my country’s only unified coal mines produce about 13.79 billion tons of coal in the "three lower" mines (buildings, railways, and water bodies), of which 9.468 billion tons of coal are pressed under buildings, accounting for about 69% of the total coal pressure. Seriously restricted the production and development of some mining areas. In addition, a large amount of coal gangue will be produced in the process of coal mine production, which is the largest type of industrial solid waste discharged and stockpiled. The stacking of gangue dumps has occupi...

Examples

Embodiment 1

[0040] (1) Collect the abandoned building concrete test blocks in the laboratory, sort and remove metal, wood, plastic and waste concrete contaminated by radioactive and heavy metal harmful substances, and then use the jaw crusher to crush the raw materials to make the crushed particles The diameter is mainly distributed below 15mm, and its raw materials are 100kg waste concrete and 50kg coal gangue, and the weight ratio of the two is 1:0.5;

[0041] (2) Sieve the crushed waste concrete and gangue particles with vibrating sieves with meshes of 1mm, 5mm and 15mm to obtain powders less than 1mm, fine aggregates of 1-5mm, and coarse aggregates of 5-15mm. The 15mm particles are sent back for re-crushing;

[0042] (3) Add fly ash and quicklime and gypsum solids mixed at a ratio of 1:0.5 to the powder obtained in step (2) with a particle size of less than 1mm, stir evenly and send it to a ball mill for ball milling, and ball mill for 15 minutes to obtain a ratio Surface area ≥ 300m...

Embodiment 2

[0046](1) Collect the abandoned building concrete test blocks in the laboratory, sort and remove metal, wood, plastic and waste concrete contaminated by radioactive and heavy metal harmful substances, and then use the jaw crusher to crush the raw materials to make the crushed particles The diameter is mainly distributed below 15mm, and its raw materials are 100kg waste concrete and 25kg coal gangue, and the weight ratio of the two is 1:0.25;

[0047] (2) Sieve the crushed waste concrete and gangue particles with vibrating sieves with meshes of 1mm, 5mm and 15mm to obtain powders less than 1mm, fine aggregates of 1-5mm, and coarse aggregates of 5-15mm. The 15mm particles are sent back for re-crushing;

[0048] (3) Add fly ash and quicklime and gypsum solids mixed at a ratio of 1:0.1 to the powder obtained in step (2) with a particle size of less than 1 mm, stir evenly, and then send it to a ball mill for ball milling for 15 minutes to obtain a ratio Surface area ≥ 300m 2 / kg ...

Embodiment 3

[0052] (1) Collect the abandoned building concrete test blocks in the laboratory, sort and remove metal, wood, plastic and waste concrete contaminated by radioactive and heavy metal harmful substances, and then use the jaw crusher to crush the raw materials to make the crushed particles The diameter is mainly distributed below 15mm, and its raw materials are 100kg waste concrete and 100kg coal gangue, and the weight ratio of the two is 1:1;

[0053] (2) Sieve the crushed waste concrete and gangue particles with vibrating sieves with meshes of 1mm, 5mm and 15mm to obtain powders less than 1mm, fine aggregates of 1-5mm, and coarse aggregates of 5-15mm. The 15mm particles are sent back for re-crushing;

[0054] (3) Add fly ash and quicklime and gypsum solids mixed at a ratio of 1:1 to the powder obtained in step (2) with a particle size of less than 1mm, stir evenly and send it to a ball mill for ball milling, and ball mill for 15 minutes to obtain a ratio Surface area ≥ 300m 2...

technical field

[0001] The invention relates to a method for preparing coal mine filling paste by using waste concrete, and belongs to the technical field of cemented filling materials. Background technique

[0002] my country is a big country of coal production and consumption. The annual coal production and consumption amount to 100 million tons. Coal accounts for more than 70% of my country's total energy structure. However, my country’s only unified coal mines produce about 13.79 billion tons of coal in the "three lower" mines (buildings, railways, and water bodies), of which 9.468 billion tons of coal are pressed under buildings, accounting for about 69% of the total coal pressure. Seriously restricted the production and development of some mining areas. In addition, a large amount of coal gangue will be produced in the process of coal mine production, which is the largest type of industrial solid waste discharged and stockpiled. The stacking of gangue dumps has occupi...

Examples

Embodiment 1

[0040] (1) Collect the abandoned building concrete test blocks in the laboratory, sort and remove metal, wood, plastic and waste concrete contaminated by radioactive and heavy metal harmful substances, and then use the jaw crusher to crush the raw materials to make the crushed particles The diameter is mainly distributed below 15mm, and its raw materials are 100kg waste concrete and 50kg coal gangue, and the weight ratio of the two is 1:0.5;

[0041] (2) Sieve the crushed waste concrete and gangue particles with vibrating sieves with meshes of 1mm, 5mm and 15mm to obtain powders less than 1mm, fine aggregates of 1-5mm, and coarse aggregates of 5-15mm. The 15mm particles are sent back for re-crushing;

[0042] (3) Add fly ash and quicklime and gypsum solids mixed at a ratio of 1:0.5 to the powder obtained in step (2) with a particle size of less than 1mm, stir evenly and send it to a ball mill for ball milling, and ball mill for 15 minutes to obtain a ratio Surface area ≥ 300m...

Embodiment 2

[0046](1) Collect the abandoned building concrete test blocks in the laboratory, sort and remove metal, wood, plastic and waste concrete contaminated by radioactive and heavy metal harmful substances, and then use the jaw crusher to crush the raw materials to make the crushed particles The diameter is mainly distributed below 15mm, and its raw materials are 100kg waste concrete and 25kg coal gangue, and the weight ratio of the two is 1:0.25;

[0047] (2) Sieve the crushed waste concrete and gangue particles with vibrating sieves with meshes of 1mm, 5mm and 15mm to obtain powders less than 1mm, fine aggregates of 1-5mm, and coarse aggregates of 5-15mm. The 15mm particles are sent back for re-crushing;

[0048] (3) Add fly ash and quicklime and gypsum solids mixed at a ratio of 1:0.1 to the powder obtained in step (2) with a particle size of less than 1 mm, stir evenly, and then send it to a ball mill for ball milling for 15 minutes to obtain a ratio Surface area ≥ 300m 2 / kg ...

Embodiment 3

[0052] (1) Collect the abandoned building concrete test blocks in the laboratory, sort and remove metal, wood, plastic and waste concrete contaminated by radioactive and heavy metal harmful substances, and then use the jaw crusher to crush the raw materials to make the crushed particles The diameter is mainly distributed below 15mm, and its raw materials are 100kg waste concrete and 100kg coal gangue, and the weight ratio of the two is 1:1;

[0053] (2) Sieve the crushed waste concrete and gangue particles with vibrating sieves with meshes of 1mm, 5mm and 15mm to obtain powders less than 1mm, fine aggregates of 1-5mm, and coarse aggregates of 5-15mm. The 15mm particles are sent back for re-crushing;

[0054] (3) Add fly ash and quicklime and gypsum solids mixed at a ratio of 1:1 to the powder obtained in step (2) with a particle size of less than 1mm, stir evenly and send it to a ball mill for ball milling, and ball mill for 15 minutes to obtain a ratio Surface area ≥ 300m 2...