RESUMEN

The creation of metal parts via casting uses molds that are generally made from sand and phenolic resin. The waste generated after the casting process is called waste foundry sand (WFS). Depending on the mold composition and the casting process, WFS can contain substances that prevent its direct emission to the environment. In Brazil, this waste is classified according to the Standard ABNT NBR 10004:2004 as a waste Class II (Non-Inert). The recycling of this waste is limited because its characteristics change significantly after use. Although the use (or reuse) of this byproduct in civil construction is a technically feasible alternative, its effects must be evaluated, especially from mechanical and environmental points of view. Thus, the objective of this study is to investigate the effect of the use of WFS in the manufacture of cement artifacts, such as masonry blocks for walls, structural masonry blocks, and paving blocks. Blocks containing different concentrations of WFS (up to 75% by weight) were produced and evaluated using compressive strength tests (35 MPa at 28 days) and toxicity tests on Daphnia magna, Allium cepa (onion root), and Eisenia foetida (earthworm). The results showed that there was not a considerable reduction in the compressive strength, with values of 35 ± 2 MPa at 28 days. The toxicity study with the material obtained from leaching did not significantly interfere with the development of D. magna and E. foetida, but the growth of the A. cepa species was reduced. The study showed that the use of this waste in the production of concrete blocks is feasible from both mechanical and environmental points of view.

Asunto(s)

Materiales de Construcción , Eliminación de Residuos/métodos , Dióxido de Silicio/química , Suelo , Aleaciones , Animales , Fuerza Compresiva , Conservación de los Recursos Naturales/métodos , Daphnia , Residuos Industriales/análisis , Metales/química , Oligoquetos , Cebollas , Compuestos Orgánicos , Tamaño de la Partícula , Fenol/química , Raíces de Plantas , Presión , Reciclaje , Espectroscopía Infrarroja por Transformada de Fourier , Estrés Mecánico , Factores de Tiempo , Pruebas de Toxicidad

RESUMEN

The analysis of the material obtained in the rescue of archaeological sites in the area surrounding the Hydroelectric Plant of Machadinho, Rio Grande do Sul, revealed that a considerable amount of bones and fish scales incorporated in the alimentary remains. Using an osteological collection as reference, we identified remains of Salminus brasiliensis (Cuvier, 1816) (Characidae), Brycon orbignyanus (Valenciennes, 1849) (Characidae), Pogonopoma obscurum Quevedo & Reis, 2002 (Loricariidae), Hemiancistrus fuliginosus Cardoso & Malabarba, 1999, Prochilodus lineatus (Valenciennes, 1836) (Prochilodontidae), Schizodon sp. (Anostomidae), Leporinus sp. (Anostomidae), Hoplias sp. (Erythrinidae), Hypostomus sp. (Loricariidae) and Crenicichla sp. (Cichlidae). Based on specimens from fish collections, regressions were obtained comparing the size of the pre-maxillary bone in Crenicichla spp. and the length of the pectoral fin spine of Hemiancistrus fuliginosus, Pogonopoma obscurum and Hypostomus spp, with the standard length and weight of corresponding specimens. The estimated size and weight of the specimens obtained from fish remains in the archaeological sites varied between 79.7-153.9 mm and 13.5-33.9 g for Hemiancistrus fuliginosus, 158.2-151.0 mm and 179.5-194.3 g for Pogonopoma obscurum, 117.1-166.2 mm and 86.6-93.1 g for Crenicichla spp., and 62.2-397.2 mm and 34-20.3 g for Hypostomus spp. Therefore using these estimates of standard lengths and weights it was possible to formulate a hypotheses on the fishing technology used by the inhabitants of these sites.

RESUMEN

The analysis of the material obtained in the rescue of archaeological sites in the area surrounding the Hydroelectric Plant of Machadinho, Rio Grande do Sul, revealed that a considerable amount of bones and fish scales incorporated in the alimentary remains. Using an osteological collection as reference, we identified remains of Salminus brasiliensis (Cuvier, 1816) (Characidae), Brycon orbignyanus (Valenciennes, 1849) (Characidae), Pogonopoma obscurum Quevedo & Reis, 2002 (Loricariidae), Hemiancistrus fuliginosus Cardoso & Malabarba, 1999, Prochilodus lineatus (Valenciennes, 1836) (Prochilodontidae), Schizodon sp. (Anostomidae), Leporinus sp. (Anostomidae), Hoplias sp. (Erythrinidae), Hypostomus sp. (Loricariidae) and Crenicichla sp. (Cichlidae). Based on specimens from fish collections, regressions were obtained comparing the size of the pre-maxillary bone in Crenicichla spp. and the length of the pectoral fin spine of Hemiancistrus fuliginosus, Pogonopoma obscurum and Hypostomus spp, with the standard length and weight of corresponding specimens. The estimated size and weight of the specimens obtained from fish remains in the archaeological sites varied between 79.7-153.9 mm and 13.5-33.9 g for Hemiancistrus fuliginosus, 158.2-151.0 mm and 179.5-194.3 g for Pogonopoma obscurum, 117.1-166.2 mm and 86.6-93.1 g for Crenicichla spp., and 62.2-397.2 mm and 34-20.3 g for Hypostomus spp. Therefore using these estimates of standard lengths and weights it was possible to formulate a hypotheses on the fishing technology used by the inhabitants of these sites.

RESUMEN

The analysis of the material obtained in the rescue of archaeological sites in the area surrounding the Hydroelectric Plant of Machadinho, Rio Grande do Sul, revealed that a considerable amount of bones and fish scales incorporated in the alimentary remains. Using an osteological collection as reference, we identified remains of Salminus brasiliensis (Cuvier, 1816) (Characidae), Brycon orbignyanus (Valenciennes, 1849) (Characidae), Pogonopoma obscurum Quevedo & Reis, 2002 (Loricariidae), Hemiancistrus fuliginosus Cardoso & Malabarba, 1999, Prochilodus lineatus (Valenciennes, 1836) (Prochilodontidae), Schizodon sp. (Anostomidae), Leporinus sp. (Anostomidae), Hoplias sp. (Erythrinidae), Hypostomus sp. (Loricariidae) and Crenicichla sp. (Cichlidae). Based on specimens from fish collections, regressions were obtained comparing the size of the pre-maxillary bone in Crenicichla spp. and the length of the pectoral fin spine of Hemiancistrus fuliginosus, Pogonopoma obscurum and Hypostomus spp, with the standard length and weight of corresponding specimens. The estimated size and weight of the specimens obtained from fish remains in the archaeological sites varied between 79.7-153.9 mm and 13.5-33.9 g for Hemiancistrus fuliginosus, 158.2-151.0 mm and 179.5-194.3 g for Pogonopoma obscurum, 117.1-166.2 mm and 86.6-93.1 g for Crenicichla spp., and 62.2-397.2 mm and 34-20.3 g for Hypostomus spp. Therefore using these estimates of standard lengths and weights it was possible to formulate a hypotheses on the fishing technology used by the inhabitants of these sites.

RESUMEN

The analysis of the material obtained in the rescue of archaeological sites in the area surrounding the Hydroelectric Plant of Machadinho, Rio Grande do Sul, revealed that a considerable amount of bones and fish scales incorporated in the alimentary remains. Using an osteological collection as reference, we identified remains of Salminus brasiliensis (Cuvier, 1816) (Characidae), Brycon orbignyanus (Valenciennes, 1849) (Characidae), Pogonopoma obscurum Quevedo & Reis, 2002 (Loricariidae), Hemiancistrus fuliginosus Cardoso & Malabarba, 1999, Prochilodus lineatus (Valenciennes, 1836) (Prochilodontidae), Schizodon sp. (Anostomidae), Leporinus sp. (Anostomidae), Hoplias sp. (Erythrinidae), Hypostomus sp. (Loricariidae) and Crenicichla sp. (Cichlidae). Based on specimens from fish collections, regressions were obtained comparing the size of the pre-maxillary bone in Crenicichla spp. and the length of the pectoral fin spine of Hemiancistrus fuliginosus, Pogonopoma obscurum and Hypostomus spp, with the standard length and weight of corresponding specimens. The estimated size and weight of the specimens obtained from fish remains in the archaeological sites varied between 79.7-153.9 mm and 13.5-33.9 g for Hemiancistrus fuliginosus, 158.2-151.0 mm and 179.5-194.3 g for Pogonopoma obscurum, 117.1-166.2 mm and 86.6-93.1 g for Crenicichla spp., and 62.2-397.2 mm and 34-20.3 g for Hypostomus spp. Therefore using these estimates of standard lengths and weights it was possible to formulate a hypotheses on the fishing technology used by the inhabitants of these sites.

RESUMEN

The analysis of the material obtained in the rescue of archaeological sites in the area surrounding the Hydroelectric Plant of Machadinho, Rio Grande do Sul, revealed that a considerable amount of bones and fish scales incorporated in the alimentary remains. Using an osteological collection as reference, we identified remains of Salminus brasiliensis (Cuvier, 1816) (Characidae), Brycon orbignyanus (Valenciennes, 1849) (Characidae), Pogonopoma obscurum Quevedo & Reis, 2002 (Loricariidae), Hemiancistrus fuliginosus Cardoso & Malabarba, 1999, Prochilodus lineatus (Valenciennes, 1836) (Prochilodontidae), Schizodon sp. (Anostomidae), Leporinus sp. (Anostomidae), Hoplias sp. (Erythrinidae), Hypostomus sp. (Loricariidae) and Crenicichla sp. (Cichlidae). Based on specimens from fish collections, regressions were obtained comparing the size of the pre-maxillary bone in Crenicichla spp. and the length of the pectoral fin spine of Hemiancistrus fuliginosus, Pogonopoma obscurum and Hypostomus spp, with the standard length and weight of corresponding specimens. The estimated size and weight of the specimens obtained from fish remains in the archaeological sites varied between 79.7-153.9 mm and 13.5-33.9 g for Hemiancistrus fuliginosus, 158.2-151.0 mm and 179.5-194.3 g for Pogonopoma obscurum, 117.1-166.2 mm and 86.6-93.1 g for Crenicichla spp., and 62.2-397.2 mm and 34-20.3 g for Hypostomus spp. Therefore using these estimates of standard lengths and weights it was possible to formulate a hypotheses on the fishing technology used by the inhabitants of these sites.