摘 要:作為一種天然產物,因使用安全、易加工及穩定性好等優良的性質,褐藻膠在食品、保健品、醫藥等健康產業中的需求日益增加。但是,褐藻膠生產過程中水資源需求量大,同時也排放大量的廢水。每生產1 t褐藻酸鈉消耗大約1 000 t淡水,排放約900 t廢水,其中,約90%的廢水為廢鈣水。綜述廢鈣水的處理技術和回用方法,分析廢鈣水處理及回用存在的問題,為廢鈣水的處理回用技術的發展提供參考。
關鍵詞:褐藻膠;廢鈣水處理;回用;化學沉淀;膜分離;離子交換
中圖分類號:X703.5 文獻標志碼:A 文章編號:2095-2945(2024)30-0136-04
Abstract: As a natural product, alginate is in increasing demand in the health industries such as food, health products, and medicine due to its excellent properties such as safe use, easy processing and good stability. However, the alginate production process requires a large amount of water resources and also discharges a large amount of wastewater. Every ton of sodium alginate produced consumes about 1 000 tons of fresh water and discharges about 900 tons of wastewater, of which about 90% is waste calcium water. The treatment technology and reuse methods of waste calcium water are reviewed, and the problems existing in the treatment and reuse of waste calcium water are analyzed to provide reference for the development of waste calcium water treatment and reuse technology.
Keywords: alginate; waste calcium water treatment; reuse; chemical precipitation; membrane separation; ion exchange
褐藻膠,也稱海藻膠,一般指褐藻酸鈉(也稱海藻酸鈉),是一種從褐藻類植物中提取的,由β-1、4-D-甘露糖醛酸(M)和α-1、4-L古羅糖醛酸(G)組成的線性高分子聚合物[1]。褐藻膠具有良好的穩定性、增稠性、凝膠性、持水性[2],能促進腸道蠕動[3],具有食用價值和藥用價值[4],被廣泛地應用在食品、生物及醫藥領域。隨著人們綠色健康理念的增強,作為天然提取物的褐藻酸鈉,因具有使用安全、易加工及穩定性好等良好的性質,在食品、保健品及醫藥等行業中的需求量日益增加。
但是,褐藻膠的生產需要消耗大量的淡水資源,產生大量的廢水。據統計,每生產1 t褐藻膠需要消耗自來水約1 000 t,兌稀用水約800 t,占總水耗的80%;排放廢水約900 t,其中,鈣離子質量濃度高于500 mg/L的廢鈣水排放量約占90%,是主要的廢水源[5]。廢鈣水中含有大量有機物及鈣鹽鈉鹽無機物,是導致廢鈣水無法回收利用的主要原因[6]。從廢鈣水處理回用至褐藻膠生產工藝的角度,針對廢鈣水的處理方法主要有化學沉淀法、膜分離法或離子交換法。……