(1. 昆明理工大學 省部共建復雜有色金屬資源清潔利用國家重點實驗室，昆明 650093；
2. 昆明理工大學 冶金與能源工程學院，昆明 650093)
摘 要: 在分析高鈣鋼渣組成結(jié)構(gòu)和浸出特性的基礎(chǔ)上，開展高鈣鋼渣在溶液中除砷行為和機理。研究結(jié)果表明：高鈣鋼渣的主要成分為鐵酸鈣、硅酸二鈣、硅酸三鈣，其浸出液pH值為12.15，具有很強的堿性；隨著鋼渣粒徑的變小或鋼渣用量的增加，溶液中砷的去除率逐漸上升。鋼渣粒徑在48~75 μm時，對溶液中的As(Ⅲ)和As(Ⅴ)的去除量分別達到0.90 mg/g和0.93 mg/g；pH對鋼渣的除砷率影響較小，經(jīng)過反應后，對砷的固定率達到99%；高鈣鋼渣去除溶液中的砷離子受化學反應速率控制。當高鈣鋼渣與含砷溶液接觸時，可對砷離子同時進行吸附和化學沉淀反應，形成較為穩(wěn)定的鈣和鐵的砷酸鹽和亞砷酸鹽，實現(xiàn)溶液中砷離子的穩(wěn)定化。含砷產(chǎn)物中砷的浸出毒性低于《危險廢物鑒別標準GB 5085.3—2007》中規(guī)定的5 mg/L，產(chǎn)物屬于一般固體廢棄物。高鈣鋼渣適用于含砷酸性廢水的無害化處置。
關(guān)鍵字: 高鈣鋼渣；除砷；吸附
（1. State Key Laboratory of Complex Nonferrous Metal Resources Clean Utilization, Kunming University of Science and Technology, Kunming 650093, China;
2. Faculty of Metallurgical and Energy Engineering, Kunming University of Science and Technology, Kunming 650093, China）
Abstract:Based on the analysis of the composition and leaching characteristics of high-calcium steel slag, the research on the removal of arsenic from the solution using high-calcium steel slag was carried out, and the arsenic removal mechanism was also explored. The high-calcium steel slag is composed of calcium ferrite, dicalcium silicate and tricalcium silicate following with pH value of 12.15 in the leaching corrosion test, revealing strong alkalinity. With the decrease of slag particle size or the increase of slag dosage, the arsenic removal rate increases gradually. When the particle size of steel slag is in the range of 48-75 μm, the removal amounts of As(Ⅲ) and As(Ⅴ) in the solution reach 0.90 mg/g and 0.93 mg/g, respectively. The pH value has slight influence on the arsenic removal rate. The arsenic fixation rate reaches 99% for arsenic-enriched steel slag after reaction. It is found that the arsenic removal in the solution using high-calcium steel slag is controlled by the chemical reaction rate. When high-calcium steel slag contacts with arsenic-containing solution, arsenic ions can be adsorbed and precipitated simultaneously to form relatively stable arsenates and arsenites of calcium and iron for the removal and stabilization of arsenic ions in the solution. The leaching toxicity of arsenic in arsenic-containing steel slag is lower than 5 mg/L, specified in the “identification standard for hazardous wastes GB 5085.3—2007”, and the products are general solid wastes. The high-calcium steel slag is suitable for the harmless disposal of arsenic-containing acid wastewater.
Key words: high calcium steel slag; arsenic removal; adsorption
