(昆明理工大學(xué) 冶金與能源工程學(xué)院，昆明 650093)
摘 要: 本文以銅冶煉過(guò)程所產(chǎn)生的含砷廢水為研究對(duì)象，研究了Fe/As摩爾比、初始pH值、氧分壓、反應(yīng)時(shí)間以及反應(yīng)溫度等宏觀技術(shù)參數(shù)對(duì)水熱臭蔥石沉砷過(guò)程及沉砷渣物相轉(zhuǎn)變的影響規(guī)律。結(jié)果表明：在Fe/As摩爾比1.5、初始pH1.0、反應(yīng)溫度160 ℃、攪拌轉(zhuǎn)速500 r/min、氧分壓0.6 MPa和反應(yīng)時(shí)間3 h的優(yōu)化技術(shù)條件下，砷與鐵的沉淀率分別為98.09%和87.64%，獲得了純度較高的臭蔥石沉砷渣；沉砷渣中砷、鐵及硫的含量分別為22.21%、25.36%及3.34%，其中硫主要以亞穩(wěn)態(tài)鐵礬的形式存在；降低Fe/As摩爾比和初始pH值、延長(zhǎng)反應(yīng)時(shí)間均有利于亞穩(wěn)態(tài)鐵礬的返溶、重結(jié)晶，進(jìn)而形成性質(zhì)穩(wěn)定的臭蔥石物相。
關(guān)鍵字: 含砷廢水；臭蔥石；沉砷率；沉鐵率；鐵礬
（Faculty of Metallurgical and Energy Engineering, Kunming University of Science and Technology, Kunming 650093, China）
Abstract:In this paper, the arsenic-containing wastewater produced by the copper smelting process was studied. The effects of macroscopic technical parameters, such as Fe/As molar ratio, initial pH, reaction temperature, oxygen partial pressure and reaction time, on the arsenic precipitate process and the phase transformation of scorodite precipitate were investigated. The experimental results indicate that, under hydrothermal conditions of initial Fe/As molar ratio of 1.5, initial pH of 1, temperature of 160 ℃, agitation speed of 500 r/min, oxygen partial pressure of 0.6 MPa and reaction time of 3 h, the arsenic and iron removal rates are 98.09% and 87.64%, respectively, the contents of As, Fe and S in scorodite precipitate are 22.21%, 25.36% and 3.34%, respectively, and the sulfur is mainly in the form of jarosite. Reducing the Fe/As molar ratio and initial pH, and extending the reaction time are all favorable for re-dissolution of metastable jarosite and recrystallization to form the stable scorodite phase.
Key words: arsenic-containing wastewater; scorodite; arsenic removal rate; iron removal rate; jarosite
