PROCESS FOR RECYCLING ALKALI LIQUOR AND REMOVING ANTIMONY THROUGH MEMBRANE TREATMENT OF ALKALI-MINIMIZATION WASTEWATER

摘要

#$%^&*AU2020102195A420201022.pdf#####Abstract The present invention provides a process for recycling alkali liquor and removing antimony through membrane treatment of alkali-minimization wastewater. The process includes: feeding alkali-minimization wastewater into a tubular ceramic ultrafiltration membrane filter, and filtering the wastewater to obtain membrane liquor and concentrated membrane liquor; recycling the membrane liquor; and conducting subsequent antimony removal operations on the concentrated membrane liquor, including: adding sulfuric acid into the concentrated membrane liquor, and regulating a pH value of the concentrated membrane liquor to be less than or equal to 4 so as to precipitate terephthalic acid; performing filter pressing, and feeding a supernatant obtained by filter pressing into an iron-carbon micro-electrolysis reactor to be treated; adding NaOH into the obtained supernatant; regulating a pH value to 8-9, and forming a Fe(OH)2 precipitate; conducting filter pressing to obtain a supernatant; then adding a strong oxidant to form a Fe(OH) 3 precipitate; and conducting filter pressing to obtain the supernatant, and taking out antimony ions in the concentrated membrane liquor by the Fe(OH) 2 precipitate and the Fe(OH) 3 precipitate. According to the present invention, the alkali liquor in the alkali-minimization wastewater is recycled, and the antimony in the alkali-minimization wastewater may be removed so as to meet related emission standards.Drawings of Description Subsequent antimony .- removalunit Concentrated liquor T Liquor Alkali-minimization Raw material Feed pump Membrane filtration Alkali liquor recycling wastewater tank system Cleaning FIG. 1 Concentrated Filter pressing SueanwiotT Comcentrated7- sulfuric acid Terephithalic acid precipitation Sup epesig ernatant withotT niembrane liquor 01 Filter NaH Iron-carbon pressing Obtaining micro-electrolysis supernatant Fe(OH): Filter Strong press Obtaining su oxidant FOH pressing Obtainingsupematantto determine Sb FIG. 2 No. Item Numerical value 1 Specific gravity 1.2 tons/m3 2 Void content 55% 3 Specific surface area 21.2m 2/M 3 4 Consumption 515% per year 5 Iron content 70-75% 6 Carbon 20% 7 Catalyst 25% 8 Appearance Flat and round 9 Particle size 2x3(cm) 10 Active ingredient Iron+ carbon+ noble metal catalyst 11 Strength 1000 kg FIG. 3 1