潘祖超,焦芬*,覃文慶,張添富,阮博文
(中南大學資源加工與生物工程學院,長沙 410083)
摘 要: 燃煤電廠煙氣脫硫過程和冶煉污酸的中和過程均產生以二水硫酸鈣為主要成分的固體廢物,前者被稱為煙氣脫硫石膏,后者通常被稱為石膏渣。煙氣脫硫石膏在建筑材料、生產化工原料、固定二氧化碳、環境治理等方面得到了有益的應用,但冶金行業石膏渣因含有砷、銅、鉛、鉻等有害元素而利用困難,通常其處置方法有固化/穩定化處置、高溫熔融處置、回收有價金屬和作為熔劑造渣等。結合國內外煙氣脫硫石膏及冶煉石膏渣綜合處置的最新研究成果,全面闡述兩者的綜合利用現狀。分析了兩類石膏渣處置與利用技術的優缺點,探討了應用中存在的一些問題與不足,并提出了建議與展望。未來煙氣脫硫石膏的研究重點是減量化、高值化,擴大脫硫石膏高值化利用規模為主,以開發高附加值產品為輔提高綜合利用率;冶煉行業石膏渣的無害化、資源化利用技術,如污酸中和過程硫酸鈣晶型調控、火法-濕法協同處理以及熔煉造渣等是未來的發展方向。
關鍵字: 煙氣脫硫石膏;石膏渣;污酸中和渣;中和污泥;無害化處置;綜合利用
Research progress on comprehensive utilization of flue gas desulfurization gypsum and gypsum slag in smelting industry
PAN Zu-chao, JIAO Fen, QIN Wen-qing, ZHANG Tian-fu, RUAN Bo-wen
(School of Minerals Processing and Bioengineering, Central South University, Changsha 410083, China)
Abstract:The Flue gas desulfurization process of coal-fired power plants and the neutralization process of smelting acid wastewater are accompanied by the generation of solid waste with calcium sulfate dihydrate as the main component. The former is called flue gas desulfurization gypsum (FGDG), while the latter is usually called gypsum slag. FGDG has been used in many ways such as building materials, production of chemical raw materials, environmental treatment, and soil remediation. It is difficult to use gypsum slag because it contains arsenic, copper, lead, chromium, and other harmful elements. The usual treatment methods are solidification/stabilization treatment, high temperature melting treatment, recovery of valuable metals, and slagging agent.This paper analyzes the advantages and disadvantages of disposal and utilization technology, discusses some problems and deficiencies existing in the application, and puts forward some suggestions.The future research should focus on FGDG minimization, expanding the high value utilization scale, and developing high value-added products to improve the comprehensive utilization rate. The technologies of harmless and resource utilization of gypsum slag, such as calcium sulfate crystal regulation, pyrometallurgical-wet synergistic treatment,and using as slagging agent are the future development directions.
Key words: Flue gas desulfurization gypsum; Gypsum slag; Sewage acid neutralizing residue; Neutralization sludge; Harmless disposal; Comprehensive utilization