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Effects of Ca2+/Mg2+ ions in recycled water on the reverse flotation properties of iron oxides

Tang Min, Yan Wu, Fu Jiahao

Physicochemical Problems of Mineral Processing

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2024

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Vol. 60, iss. 3

art. no. 188465

EN

Water quality, particularly hardness, plays an important role in affecting the floatability of minerals as it interferes with the chemical/electro-chemical characteristics of mineral surfaces and their interactions with flotation reagents. It could become unpredictable when water sources characterized by different calcium or magnesium ion distributions were involved. This study aimed to identify the role of Ca2+/Mg2+ ions in the recycled water on the cationic reverse flotation selectivity of iron oxides through a series of bench/micro flotation tests, zeta potential, powder contact angle, and Fourier Transform Infrared (FTIR), etc. The results pointed out that the use of recycled tailing water deteriorates the flotation selectivity and dilutes the concentrates. This can be largely attributed to the presence of Ca2+ ions at higher concentrations as they induce a drop in the Fe recovery and an increase in SiO2 content while an increase in the content of Mg2+ ions seems to have little effect on the quality of concentrate. As evidenced by the data from micro-flotation, powder contact angle, zeta potentials, and FTIR, a hydrophilic colloidal layer formed by Ca-based hydrolyzed compounds, such as Ca(OH)+ or, CaCO3(s), etc., on quartz could change its zeta potentials and disturb its interactions with a cationic collector. They also play a role in weakening the flocculation of starch on hematite probably by prelocking the acidic groups on the starch remnants and contracting their configurations, thus preventing their adsorption on mineral surfaces. However, magnesium ions seem to be beneficial to in strengthening the flocculation of starch on hematite as magnesium-based species could act as adsorption bridges of between starch and mineral surfaces.

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Effect of different process water sources on rougher flotation efficiency of a copper ore : A case study at Sarcheshmeh Copper Complex (Iran)

Soufiabadi Amir Mousa, Nejadaria Milad, Dehghan Reza, Safari Mehdi, Hassanzadeh Ahmad, Khoshdast Hamid

Physicochemical Problems of Mineral Processing

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2023

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Vol. 59, iss. 5

art. no. 184087

EN

In this research, the effect of different sources of process water on the flotation efficiency of copper sulfide ore prepared from the Sarcheshmeh copper mine was investigated. For this purpose, samples of fresh water to the plant, overflows of copper-molybdenum concentrate thickener, copper concentrate thickener, and recycled water pool as well as a mixture of fresh water and recycled water were prepared and characterized. Flotation tests were performed under the same conditions as the plant’s rougher circuit and were kept constant during all experiments. Grade and recovery of copper, iron, molybdenum, and silica were selected as the metallurgical response of flotation tests. The results were subjected to statistical analysis to assess the relative significance of which water source affects the flotation performance as evaluated from the experimental results. The results showed that the copper concentrate thickener overflow had the greatest effect on the flotation efficiency, so the grade and recovery decreased by about 10% and 75% for copper, and 10% and 6% for iron in the concentrate, respectively, while the grade and recovery increased up to 0.1% and 12% for silica, and 3% and 25% for molybdenum, respectively. The reason for this effect was attributed to the high content of suspended solid particles, and Cu2+, Mo2+, and Fe2+ cations in this water source that increased the coating effect over gangue minerals and entrainment rate. The improvement of molybdenum flotation was also ascribed to the possible presence of residual diesel oil from the flotation process in the plant. Due to the relatively equal amount in all sources of process water, the effect of anions and ions of dissolved salts was difficult.

3

Study the Effects of Using Different Water Types on the Mechanical Properties of Concrete

Fadil Sanad Aldeen, Al Kindi Ghayda Y., Tobeia Sameh B.

Ecological Engineering & Environmental Technology

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2023

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Vol. 24, iss. 1

175--184

EN

The issue of water sustainability is a major topic due to the lack of water sources and the scarcity of drinking water, so the search for alternatives began. In this paper, the effect of using three water sources will be studied (the tap water (as control reference mix.), the Tigris River, and the Pepsi Company factory). To study the physical and chemical properties, and the effect of this water on the concrete mixture, and for each source the concrete mixture was placed in cube molds and cylinders. Put the concrete mixture in a water basin for curing. Compression and splitting tests are performed at intervals of (7-28-90) days to evaluate these mixtures. From the results it was found that the compressive and splitting strength of concrete for tap water, Tigris River and Pepsi factory, which was recorded at the age of 7 days, the compressive strength of cubes was an average of 18.5 MPa, 19 MPa and 13 and the splitting strength was an average of 1.5 MPa and 1.4 MPa and 0.5 MPa, respectively, at the age of 28 days, which were recorded at 32.1 MPa, 28 MPa, and 16.4 MPa, respectively, and the splitting strength was 3 MPa, and 2.7 MPa, and 1.5 MPa, respectively, and at 90 days they were 36 MPa, 32 MPa, and 18 MPa, respectively, and the splitting strength was 3.2 MPa, 3 MPa, and 1.7 MPa respectively also was observed a decrease in compressive strength and splitting by more than 40% for Pepsi Baghdad company factory wastewater samples. Finally, the drinking water and the water of the Tigris River was suitable for making concrete mixtures.

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Nowa technologia aktywacji granulowanego żużla wielkopiecowego za pomocą wody z produkcji betonu towarowego

Ryou J. S., Song II. H., Kim S. S., Lee J. B.

Cement Wapno Beton

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2013

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R. 18/80, nr 1

33--38

PL

W pracy przedstawiono doświadczalne wyniki aktywacji granulowanego żużla wielkopiecowego za pomocą odpadowej wody z produkcji betonu towarowego. Wykazano, że ten odpad ma pH większe od 12 i jako woda zarobowa może stanowić dobry aktywator żużla. Wytrzymałość na ściskanie zapraw żużlowych zwiększała się wraz ze wzrostem zawartości fazy stałej w tej odpadowej wodzie, w całym objętym doświadczeniami zakresie od 1% do 10%. Natomiast skurcz suszenia był taki sam jak porównawczej zaprawy z cementu portlandzkiego tylko do zawartości fazy stałej wynoszącej 3%. W przypadku wyższych zawartości, to jest 5%, 7% i 10%, był znacznie większy. Biorąc to pod uwagę autorzy proponują stosować jako aktywator wodę odpadową zawierającą maksymalnie 3% fazy stałej.

EN

The work presents the results of granulated blastfurnace slag activation with recycling water from ready-mixed concrete production. It was shown that this water has high pH level and used as mixing water is a good activator for slag. The compressive strength of mortars was increasing with the content of solid phase in this water, and in examined samples ranged from 1% to 10%. The drying shrinkage of mortars were close to the reference mortar from Portland cement until 3% of solid phase content in recycled water. However, if solid phase content was higher, namely 5%, 7% and 10% the shrinkage was much higher. Taking this mortar behavior into consideration, according the authors only recycled water containing up to 3% of solid phase can be used as slag activator.

5

Ocena funkcjonowania systemu nawodnień kroplowych w warunkach nawadniania oczyszczonymi ściekami

Wagner A., Jeznach J., Ptach W.

Przegląd Naukowy Inżynieria i Kształtowanie Środowiska

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2003

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Vol. 12, No. 2

20--26

EN

The quality of irrigation water has an impact on operation of irrigation system and influence on system efficiency. The main objective of the experiments was to examined the performance of drip system under conditions of low quality recycled water irrigation from tobacco manufacture. The results of uniformity coefficients were higher then 90% and performance of the drip system can be evaluated as acceptable.