Concrete admixture and a method for preparing the concrete admixture by calcining coal gangue

Abstract

The invention relates to a concrete admixture, Which is made from a A component and a B component by steps of mixing, calcining and grinding; the A component includes following raw materials: coal gangue of 70 to 90 amounts by weight; limestone of 10 to 30 amounts by weight; gypsum of 2 to 5 amounts by weight; fluorite of 0.5 to 1.5 amounts by weight; The B component is standard coal; The calorific value of the mixed A and B components is more than 1600 kcal / kg. The invention also provides a method of preparing above mentioned concrete admixture by calcining coal gangue with a fluidized bed roaster, That is mixing the components well and sending into the fluidized bed roaster calcining for one to two hours at a temperature of 800 to 900 degrees, And then pulling out of the roaster for cooling, At last grinding into fine powder and screening to obtain products. The invention uses a simple technology, Increases utilization rate of coal gangue, Which is benefit for full use of the coal gangue, Being used as concrete admixture, With the advantages of more than 30% to 50% active amount, Low cost, Which can increasing intensity of concrete, Increasing impermeability and durability performance, And excellent performance.

Description

technical field [0001] The invention relates to a concrete admixture and a preparation method thereof, in particular to a method for preparing a concrete mineral admixture by calcining coal gangue in a fluidized fluidized furnace, and a concrete admixture with coal gangue as a main raw material. Background technique [0002] Coal gangue is a kind of mixed rock mass discharged during the construction and production of coal mines. It includes the gangue discharged during the tunneling of coal mines, the gangue stripped during open-pit coal mining, and the gangue discharged during the washing process. The amount of coal gangue accounts for about 10% to 25% of coal mining. The stacking of coal gangue in my country has formed 1,500 gangue hills, and the total amount of gangue stored in the country is about 4 billion tons, covering an area of ​​nearly 300,000 mu. Estimated that gangue discharge accounts for 20% of raw coal production, the newly added gangue is more than 200 milli...

AI Technical Summary

Problems solved by technology

[0003] At present, coal gangue is mostly used for power generation, as cement raw fuel, brick making, underground filling, land reclamation, road construction, etc., but the total consumption is still very low, and the utilization rate is not high

In particular, only 5-20mm particles are selected for crushing coal gangue used as the aggregate of asphalt concrete, and most of the fine powder particles smaller than 5mm, which account for 25% of the total amount of crushing, are directly discarded or piled up, resulting in a large waste of resources.

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