In the disclosed solution, a method is described for producing sand used in industry, in which method discarded power plant and/or foundry sand is processed into sand for use in products of the construction industry and/or into foundry sand via pre-treatment, drying, and after-treatment. In addition, an apparatus is described for producing sand used in industry, and use of discarded power plant and/or foundry sand in products of the construction materials industry or in foundry industry.

A regeneration treatment method of waste shell-mold and a system thereof are provided. The regeneration treatment method has a raw smashing step, a smashed-particle sieving step smashed-particle, a first magnetic separation step, a grinding step, a second magnetic separation step, a dry pneumatic flotation step, and a vibration sieving step in sequence to obtain a regenerated shell-mold sand. The refined shell-mold sand is obtained from the smashed-particle sieving step. Silica binders of the refined shell-mold sand is effectively removed by the grinding step. Furthermore, particle sizes of the regenerated shell-mold sand fall in a suitable range in the grinding step. Magnetic metals mixed in the waste shell-mold are effectively removed by the first and second magnetic separation steps. Non-magnetic impurity are further removed by the dry pneumatic flotation step. Therefore, the regenerated shell-mold sand are suitable to substitute original shell-mold sand.

A regeneration treatment method of waste shell-mold and a system thereof are provided. The regeneration treatment method has a raw smashing step, a smashed-particle sieving step smashed-particle, a first magnetic separation step, a grinding step, a second magnetic separation step, a dry pneumatic flotation step, and a vibration sieving step in sequence to obtain a regenerated shell-mold sand. The refined shell-mold sand is obtained from the smashed-particle sieving step. Silica binders of the refined shell-mold sand is effectively removed by the grinding step. Furthermore, particle sizes of the regenerated shell-mold sand fall in a suitable range in the grinding step. Magnetic metals mixed in the waste shell-mold are effectively removed by the first and second magnetic separation steps. Non-magnetic impurity are further removed by the dry pneumatic flotation step. Therefore, the regenerated shell-mold sand are suitable to substitute original shell-mold sand.