A chemical regeneration method of water glass used sand is provided in the present disclosure, which belongs to the field of resource recycling in the casting industry. The present disclosure adopts a two-component reagent composed of calcium oxide and tap water, emulsion composed of sucrose and calcium oxide, and calcium chloride aqueous solution to process the regeneration of the used sand, and prepares the sample of the reclaimed sand obtained after the reagent mixed with the used sand is sealed and placed for 0 to 24 hours respectively, and tests the properties of the sample including: initial strength, final strength and collapsibility, and sodium carbonate content, and compares the properties of raw sand and used sand after the tests. Among several regeneration methods, each property index of the reclaimed sand obtained by using calcium oxide and tap water to regenerate for 12 hours is the best.

A chemical regeneration method of water glass used sand, which belongs to the field of resource recycling in the casting industry. The present invention adopts a two-component reagent composed of calcium oxide and tap water, an emulsion composed of sucrose and calcium oxide, and a calcium chloride aqueous solution to process the regeneration of the used sand, and prepares the sample of the reclaimed sand obtained after the reagent mixed with the used sand is sealed and placed for 0 to 24 hours respectively, and tests the properties of the sample including: initial strength, final strength and collapsibility, and sodium carbonate content, and compares the properties of raw sand and used sand after the tests. Among several regeneration methods, each property index of the reclaimed sand obtained by using calcium oxide and tap water to regenerate for 12 hours is the best.

A chemical regeneration method of water glass used sand, which belongs to the field of resource recycling in the casting industry. The present invention adopts a two-component reagent composed of calcium oxide and tap water, an emulsion composed of sucrose and calcium oxide, and a calcium chloride aqueous solution to process the regeneration of the used sand, and prepares the sample of the reclaimed sand obtained after the reagent mixed with the used sand is sealed and placed for 0 to 24 hours respectively, and tests the properties of the sample including: initial strength, final strength and collapsibility, and sodium carbonate content, and compares the properties of raw sand and used sand after the tests. Among several regeneration methods, each property index of the reclaimed sand obtained by using calcium oxide and tap water to regenerate for 12 hours is the best.

An apparatus and a method for cleaning sand used at a foundry, wherein sand to be cleaned is screened by a screening apparatus. The screened sand and at least one liquid mixture is fed into an abrasive apparatus. After that, the screened sand is rubbed by the abrasive apparatus. The rubbed sand and at least one liquid mixture is added to a water separation screen for separating a water blend from the rubbed sand. Finally, the separated sand is transferred into an oven and cleaned thermally by rotating the separated sand in the heated oven.

An apparatus and a method for cleaning sand used at a foundry, wherein sand to be cleaned is screened by a screening apparatus. The screened sand and at least one liquid mixture is fed into an abrasive apparatus. After that, the screened sand is rubbed by the abrasive apparatus. The rubbed sand and at least one liquid mixture is added to a water separation screen for separating a water blend from the rubbed sand. Finally, the separated sand is transferred into an oven and cleaned thermally by rotating the separated sand in the heated oven.

In the disclosed solution, a method is described for producing sand used in industry, in which method dis-carded power plant and/or foundry sand is processed into sand for use in products of the construction industry and/or into foundry sand by means of 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.

In the disclosed solution, a method is described for producing sand used in industry, in which method dis-carded power plant and/or foundry sand is processed into sand for use in products of the construction industry and/or into foundry sand by means of 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.

In the disclosed solution sand to be cleaned is thermally cleaned by rotating the sand being cleaned in a large oven (1) by rotating the oven (1). Before cleaning, the sand may be pre-processed by crushing any lumps and cleaning the sand fraction by magnetic separation. Preprocessed sand to be cleaned and heat energy are fed (5) into the rotating oven. The oven (1) is set slightly inclined so that a second end of the oven (1) is lower than a first end. The inclination and rotating speed of the oven (1) as well as the feed amount of sand are adjusted, whereby the advancing speed of the sand may be adjusted, as well as the ratio of the sand being cleaned to the volume of the oven (1) kept as desired. The temperature of the oven (1) is monitored at the coldest area of the oven, which is substantially at the second end of the oven. The temperature of the oven (1) is adjusted by adjusting the amount of heat energy fed in. By means of temperature monitoring and knowing the advancing speed of the sand, it is also possible to determine the average temperature of the sand and adjust it as desired by adjusting the supplied heat energy. Finally, the cleaned sand is let run (12) from the second end of the oven (1).

In the disclosed solution sand to be cleaned is thermally cleaned by rotating the sand being cleaned in a large oven (1) by rotating the oven (1). Before cleaning, the sand may be pre-processed by crushing any lumps and cleaning the sand fraction by magnetic separation. Preprocessed sand to be cleaned and heat energy are fed (5) into the rotating oven. The oven (1) is set slightly inclined so that a second end of the oven (1) is lower than a first end. The inclination and rotating speed of the oven (1) as well as the feed amount of sand are adjusted, whereby the advancing speed of the sand may be adjusted, as well as the ratio of the sand being cleaned to the volume of the oven (1) kept as desired. The temperature of the oven (1) is monitored at the coldest area of the oven, which is substantially at the second end of the oven. The temperature of the oven (1) is adjusted by adjusting the amount of heat energy fed in. By means of temperature monitoring and knowing the advancing speed of the sand, it is also possible to determine the average temperature of the sand and adjust it as desired by adjusting the supplied heat energy. Finally, the cleaned sand is let run (12) from the second end of the oven (1).

A method for regenerating foundry sand, in particular for the renewed production of foundry molds and/or foundry mold cores from the regenerated foundry sand, through removal of binding agent, from a foundry sand/binding agent mixture, using a solid support means (6), wherein binding agent and support means (6) are separated from the foundry sand, wherein support means (6) is brought into contact with the foundry sand/binding agent mixture, is preferably added to it, and, together with the binding agent, which adheres thereto and/or which is incorporated therein, is separated from the foundry sand (10).