Comprehensive utilization of limestone sandstone mine tailings

January.14,2021

Limestone is a kind of sedimentary rock, the main components are calcium carbonate and magnesium carbonate, etc. The tailings produced by sandstone processing are mainly stone chips and stone powder. Stone chips can generally replace fine aggregate and crushed stone to be used as building foundation fillers, or be ground and stone powder at the same time as resource treatment; limestone powder can be used according to its physical and chemical properties, such as concrete, cement and PC The component admixture can also be used as a high-calcium solvent for power plant desulfurization and metallurgy. In addition to the construction industry, limestone sandstone mine tailings have certain applications in the chemical, metallurgical, and even agricultural and pharmaceutical industries.

Comprehensive utilization of stone chips

After further shaping and screening, most of the stone chips produced during the processing and production of sand and gravel aggregates can be used as concrete fine aggregates. However, there are still a small amount of stone chips due to their powder content and needle-like granular particles. It can’t be used as concrete fine aggregate, which becomes tailings.

In some construction projects, this part of stone chips is often used to replace natural sand and gravel as the engineering foundation. In the current situation that a large number of rivers and rivers are prohibited from mining, it can be described as an efficient and economical foundation treatment method. Not only the strength is high, the compressibility is low, the ability to dissipate the additional stress on the upper part is strong, but also the cost is low, the construction is simple, and the resources are saved, and significant economic and social benefits have been achieved.

In addition, it is also possible to consider the simultaneous resource treatment of stone chips and stone powder, such as grinding them as concrete admixtures, concrete precast parts, etc., to maximize the use of stone chips.

Comprehensive utilization of stone powder

Stone powder refers to powdery particles with a particle size less than 0.075mm (the defined particle size in hydraulic concrete is less than 0.16mm) produced during the processing of building sand and gravel aggregates. The comprehensive utilization of powdered stone varies with the lithology and properties of its parent rock.

(1) Concrete admixture
Limestone powder is an inert admixture. As a concrete admixture, limestone powder has significant advantages and feasibility.
(2) Prefabricated component admixture

The new prefabricated component system has the advantages of fast construction speed, easy quality control, material saving, good appearance quality of components, good durability, reduced on-site wet work, and environmental protection.