Process of Wet-reclamation of Used Fused Ceramic Sand
The process of wet regeneration of used Fused Ceramic Sand is shown in the following figure. Take out the sand mold that is broken after casting, first crush it mechanically with low strength to less than 3mm, then select magnetism after screening to remove the metal block in the sand, then wet scrub the old sand to remove the alkaline phenolic resin film adhered to the sand surface, then dry it, and finally test the performance of the recycled sand, After reaching the casting requirements, it can be put into production.
Used sand → crushing→ screening→ magnetic separation→ wet scrubbing→ drying→ reclaimed sand performance test
Thermal regeneration process of Fused Ceramic Sand
The process of thermal regeneration of Fused Ceramic Sand is shown in the following figure, which is the same as the wet regeneration process of Fused Ceramic Sand. First, the old sand after pouring and dropping box needs to be pre-treated, that is, it is mechanically crushed to less than 3mm with low strength, and then magnetic selected to remove the metal blocks in the sand after screening. Then the appropriate heating temperature and holding time were selected for high-temperature roasting to remove the residual alkaline phenolic resin film on the particle surface. Next, the sand should be cooled to room temperature for use. In industry, the waste heat of the sand should be utilized, or it should be cooled by water cooling and other methods. The amount of sand used in each experiment in the laboratory is relatively small, and it can be cooled to room temperature in a dry dish. Finally, the performance of recycled sand is tested, and it can be put into production after reaching the casting requirements.
Used sand→ crushing→ screening→ magnetic separation→ high temperature roasting →cooling → performance test of reclaimed sand
Test method for properties of reclaimed Fused Ceramic Sand
In order to determine whether the quality of the reclaimed sand obtained after regeneration treatment is qualified and whether it can be put into production to replace the new sand for recycling, the performance of the reclaimed sand needs to be tested. There are many test indicators for the performance of recycled sand. At present, foundry scholars often measure water content, mud content, particle size, average fineness, compactness, air permeability, strength (tensile strength, compressive strength, flexural strength, shear strength, etc.), loss on ignition, acid consumption, gas generation, gas generation speed, etc., which affect each other, There are certain connections, not completely isolated. Therefore, it is not necessary to measure all the performance indexes of the sand one by one. By analyzing several representative performance test results, we can understand the overall performance of the sand and evaluate the quality of the sand, so as to know whether it can meet the casting production conditions. This paper mainly investigates the loss on ignition, 24h tensile strength of recycled Fused Ceramic Sand, and observes its surface micro morphology. Through the discussion and analysis of the above three performance test results, we can understand the quality of recycled Fused Ceramic Sand, judge whether it can meet the casting conditions, and then verify the success of the old Fused Ceramic Sand recycling process.