{'fraction_non_alphanumeric': 0.031465848042977744, 'fraction_numerical': 0.03607060629316961, 'mean_word_length': 4.3884297520661155, 'pattern_counts': {'":': 0, '<': 0, '<?xml version=': 0, '>': 0, 'https://': 0, 'lorem ipsum': 0, 'www.': 0, 'xml': 0}, 'pii_count': 0, 'substrings_counts': 0, 'word_list_counts': {'cursed_substrings.json': 0, 'profanity_word_list.json': 0, 'sexual_word_list.json': 0, 'zh_pornsignals.json': 0}}
Effect of AlF3 Production Waste on the Properties of Hardened Cement Paste

The possibility to use by-product SiO 2 · n H 2 O (often called AlF 3 production waste) in cement casting has been attracting the interest of researchers for many years, although high content of fluorine makes the use of amorphous SiO 2 problematic. Finding the way of utilizing waste products is a very important research topic at the moment. In this study AlF 3 production waste was investigated as the basic ingredient of a new pozzolanic material. The goal of this study is to investigate the possibilities of using AlF 3 production waste, washed in ammonia solution, in cement stone specimens. Chemically treated silica gel additive was proved to reduce the amount of Ca(OH) 2 and CaCO 3 in hardened cement paste samples. Experimental research has revealed that the density in hydrated samples reduces from 2220 kg/m 3 to 2030 kg/m 3 with the increase of silica gel content from 0 % to 35 %. The compressive strength of samples containing 10 % of silica gel additive increased by 8.04 % compared to the samples without the additive. SiO 2 additive used at 10 % and 20 % increased the maximum hydration temperature. In this case, the additive modifies the hydration kinetics. DOI: http://dx.doi.org/10.5755/j01.ms.18.2.1925