The regeneration of waste foundry sand and residue stabilization using coal refuse

Park, Chong-Lyuck; Kim, Byoung Gon; Young-Chul, Yu

doi:10.1016/j.jhazmat.2011.11.100

Cited by 29 publications

(11 citation statements)

References 9 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Dry regeneration removes the binder on the sand surface using friction, making this process significantly simple compared to other methods. However, the coproduced dust during dry regeneration negatively affects the working environment and the quality of the regenerated sand [12,13]. Thermal regeneration removes the binder using a high-temperature treatment (> 600°C), which is energy costly and causes the emission of harmful gases [13].…”

Section: Introductionmentioning

confidence: 99%

“…However, the coproduced dust during dry regeneration negatively affects the working environment and the quality of the regenerated sand [12,13]. Thermal regeneration removes the binder using a high-temperature treatment (> 600°C), which is energy costly and causes the emission of harmful gases [13]. In contrast, wet regeneration uses water and chemical solutions for binder removal, and produces better-quality reused sand than other methods [12,14].…”

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Wet regeneration of waste artificial sand used in sand casting using chemical solutions

Kim

Baek

et al. 2020

Environmental Engineering Research

View full text Add to dashboard Cite

Natural sand and organic binders have been the main materials used in sand casting. However, inorganic binders are used in novel casting technologies, and research on artificial sand as a substitute of natural sand has been conducted. Herein, the wet regeneration of waste artificial sand was performed using a sodium silicate binder. Acidic, neutral, and basic solutions were used for wet regeneration. The effects of binder removal and reusability of the regenerated sand were investigated by comparing the characteristics and strengths of the artificial and regenerated sand. It was demonstrated that the basic solution effectively removed the binder from the surface of the waste artificial sand. The Si-O-Si bond cleavage in the binder occurred due to the high concentration of hydroxide ions in the basic solution. The strength of the regenerated sand treated with the basic solution and that of the artificial sand were similar. Moreover, the strengths of regenerated sands treated with the acidic or neutral solutions were lower than that of artificial sand due to the presence of residual binder. These results indicated that the basic solution was suitable for removing the sodium silicate binder. The quality of the regenerated sand was similar to that of artificial sand.

show abstract

Section: Introductionmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

Wet regeneration of waste artificial sand used in sand casting using chemical solutions

Kim

Baek

et al. 2020

Environmental Engineering Research

View full text Add to dashboard Cite

show abstract

“…Studies about recycling examining the application of foundry wastes have been carried out worldwide. According to several studies, these wastes can be recycled or reused in different ways, in foundry manufacturing itself or in other industrial processes as building materials [3][4][5][6][7]. The results thereof are useful to conceive strategies to avoid disposal costs and reduce raw material costs.…”

Section: Introductionmentioning

confidence: 99%

“…Nevertheless, thermomechanical methods to regenerate foundry sands have been investigated in the effort to mitigate the effects of environmental degradation as much as possible, improve conservation of sand extraction sites, considering in-house recycling as the best solution for valuation of a waste according to the cleaner production concepts [11,12]. [13] tested two processes for the recycling and residue stabilization of waste foundry sands, considering the dry mechanical process for recycling, and the stabilization process for powdered residue. The results showed that coal refuse and sodium silicate stabilize heavy metals better than other processes may lead to the development of a cost-effective solution for stabilizing heavy metals in residues.…”

Section: Introductionmentioning

confidence: 99%

Thermal regeneration of waste foundry phenolic sand in a lab scale fluidized bed

et al. 2018

View full text Add to dashboard Cite

Improper disposal of sand used in molding processes after casting increases logistical costs and environmental impact because of the presence of the phenolic resin in its composition. The regeneration process of waste foundry phenolic sand (WFPS) aims to recycle this material. As mechanical regeneration methods are not efficient to guarantee 100% cleaning of the sand grains and their use again in the molding process, this work investigated the efficiency of a method of thermal regeneration of this type of residue that can be employed as a complementary procedure. A laboratory-scale fluidized bed reactor was designed and built to regenerate WFPS that was previously treated by a mechanical method. The methodology used to design and construct the fluidized bed prototype is described, as well as the characterization of the residual, the standard clean sand and the regenerated sand. The results of the thermal regeneration in the fluidized bed were very satisfactory with respect to the regeneration efficiency. For the nine process conditions tested, loss on ignition values were reduced when compared to standard clean sand. This study presents the advantages of a combination of two processes, mechanical and thermal regeneration, which allows to reduce the time and eventual temperature of resin removal due to the partial removal of the resin layer or its weakening during the mechanical regeneration process. Of the nine process conditions tested, six had loss on ignition values below the CSS. Thus, the thermal regeneration in the fluidized bed results was quite satisfactory in relation to the regeneration efficiency.

show abstract

“…It is well known that coal gangue mainly consists of about 20 wt.% carbon, 25 wt.% alumina, and 48 wt.% silica, and so sodium silicate could be made from the waste [17][18][19][20]. However, in the literatures, the SBA-15 synthesized using sodium silicate from coal gangue as a silica source was not reported.…”

Section: Introductionmentioning

confidence: 99%

Hydrothermal Synthesis of SBA‐15 Using Sodium Silicate Derived from Coal Gangue

Wang

Cheng

et al. 2013

Journal of Nanomaterials

View full text Add to dashboard Cite

Well-ordered SBA-15 was prepared with a hydrothermal route by sodium silicate derived from coal gangue. The as-prepared sample was analyzed by SAXRD, BET, TEM, and SEM, respectively. The results indicate that at a low hydrothermal temperature of 100∘C the well-ordered mesoporous SBA-15 could be synthesized. The surface area, pore volume, and pore size of the sample are 552 m2/g, 0.54 cm3/g, and 7.0 nm, respectively. It is suggested that coal gangue could be used in obtaining an Si source to prepare mesoporous materials, such as SBA-15.

show abstract

The regeneration of waste foundry sand and residue stabilization using coal refuse

Cited by 29 publications

References 9 publications

Wet regeneration of waste artificial sand used in sand casting using chemical solutions

Wet regeneration of waste artificial sand used in sand casting using chemical solutions

Thermal regeneration of waste foundry phenolic sand in a lab scale fluidized bed

Hydrothermal Synthesis of SBA‐15 Using Sodium Silicate Derived from Coal Gangue

Contact Info

Product

Resources

About