Title |
Utilisation of by-product phosphogypsum through extrusion-based 3D printing / |
Authors |
Sinka, Maris ; Vaičiukynienė, Danutė ; Nizevičienė, Dalia ; Sapata, Alise ; Villalón Fornés, Ignacio ; Vaitkevičius, Vitoldas ; Šerelis, Evaldas |
DOI |
10.3390/ma17225570 |
Full Text |
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Is Part of |
Materials.. Basel : MDPI. 2024, vol. 17, iss. 22, art. no. 5570, p. 1-14.. ISSN 1996-1944 |
Keywords [eng] |
phosphogypsum ; 3D printing ; building materials ; recycling materials |
Abstract [eng] |
Phosphogypsum (PG) is a phosphate fertiliser by-product. This by-product has a low level of utilisation. Calcium sulphate is dominated in PG similar to gypsum and, therefore, has good binding properties (similar to natural gypsum). However, the presence of water-soluble phosphates and fluorides, an unwanted acidic impurity in PG, makes PG unsuitable for the manufacture of gypsum-based products. In this study, the binding material of PG (β-CaSO4·0.5H2O) was produced from β-CaSO4·2H2O by calcination. To neutralise the acidic PG impurities, 0.5 wt% quicklime was added to the PG. In the construction sector, 3D-printing technology is developing rapidly as this technology has many advantages. The current study is focused on creating a 3D-printable PG mixture. The 3D-printing paste was made using sand as the fine aggregate and a binder based on PG. The results obtained show that, despite the low degree of densification, 3D printing improves the mechanical properties of this material compared to cast samples. The 3D-printed specimens tested in [u] direction reached the highest compressive strength of 950 kPa. The cast specimens showed a 17% lower compressive strength of 810 kPa. The 3D-printed specimens tested in the [v] and [w] directions reached a compressive strength of 550 kPa and 710 kPa, respectively. |
Published |
Basel : MDPI |
Type |
Journal article |
Language |
English |
Publication date |
2024 |
CC license |
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