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Usuwanie zanieczyszczeń w wodach technologicznych metalurgii metali nieżelaznych za pomocą reakcji Fentona

100%

Kurowski R. , Czaplicka M. , Fijałkowska A. , Bratek Ł.

tom R. 58, nr 7

365-369

W artykule przedstawiono wyniki badań laboratoryjnych utleniania wody technologicznej, charakteryzującej się wysokim ChZT oraz pH < 2, za pomocą nadtlenku wodoru oraz odczynnika Fentona. Badania prowadzono przy różnych stosunkach masowych ChZT: H2O2 oraz ChZT: H2O2:Fe2+. Stwierdzono, że najwyższe obniżenie tego parametru wynoszące 44 % nastąpiło dla zależności ChZT(gO2) : H2O2(g) jak 1,0 : 2,5. Przebieg zmian ChZT w funkcji czasu wskazuje, że reakcje chemiczne prowadzące do obniżenia tego parametru zachodzą bezpośrednio po dodaniu utleniacza. Wyniki badań możliwości wykorzystania reakcji Fentona do obniżenia ChZT wykazały, najwyższy spadek wartości tego parametru, o około 64 %, nastąpił przy stosunku reagentów ChZT(gO2) : H2O2(g) : Fe2+(g) równym 1,0 : 2,5 : 1,25. Korekcja pH do poziomu około 3 pozwoliła na zwiększenie efektywności spadku ChZT o 77 %. Dodatek zarówno nadtlenku wodoru, jak i odczynnika Fentona prowadził do powstawania fazy stałej zbudowanej głównie z żelaza, arsenu oraz jonów siarczanowych (VI).

The study presents results of laboratory investigations into oxidation of process water of high COD and pH < 2, with application of hydrogen peroxide and Fenton’s reagent. The studies were conducted at various COD: H2O2 and COD:H2O2:Fe2+ ratios. It was found out that the highest reduction (44 %) of the parameter was reached for COD(gO2):H2O2(g) of 1.0:2.5. Changes of COD with time indicate that chemical reactions leading to reduction of the parameter take place immediately after oxidizer addition. Investigations into possibilities for application of Fenton reaction for COD reduction showed that the biggest reduction of that parameter, of about 64 %, was reached at COD(gO2):H2O2(g):Fe2+(g) ratio of 1,0 : 2,5 : 1,25. Correction of pH to the level of about 3 brought increase in COD reduction efficiency by 77 %. Both addition of hydrogen peroxide and Fenton’s reagent resulted in formation of solid phase which was mainly composed of iron, arsenic and sulfate(VI) ions.

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

100%

Soufiabadi A. M. , Nejadaria M. , Dehghan R. , Safari M. , Hassanzadeh A. , Khoshdast H.

2023

tom Vol. 59, iss. 5

art. no. 184087

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.