单宁酸在冷却水中的阻垢性能研究

Study on the scale inhibition performance of tannic acid in cooling water

采用碳酸钙沉积法对单宁酸在冷却水中的阻垢性能进行了试验研究,考察了温度、碱度、硬度和金属离子等因素对其阻垢性能的影响。结果表明,单宁酸对碳酸钙具有较好的阻垢性能,当温度低于70℃、单宁酸质量浓度为20 mg/L时,阻垢率可达到72%;高碱度和高硬度条件下,单宁酸对碳酸钙的阻垢率会有一定程度的下降;Fe3+对单宁酸的阻垢有抑制作用,而Cu2+虽对单宁酸的阻垢具有协同作用,但会加大管道腐蚀,所以Cu2+浓度不宜过高。

Calcium carbonate precipitation method has been used for studying the scale inhibition performance of tannic acids in cooling water. The effects of influencing factors including temperature, basicity, hardness and metal ions on scale inhibition performance are studied. The results show that tannic acid has better scale inhibition effect on calcium carbonate. When the temperature is lower than 70℃and mass concentration of tannic acid 20 mg/L, the scale inhibiting rate reaches 72%. Under high basicity and high hardness conditions,the scale inhibiting effect of tannic acid on calcium carbonate may decline to a certain degree. Fe3＋can inhibit the scale inhibition of tannic acid. Although Cu2＋ has synergistic effect on the scale inhibition of tannic acid,it may lead to corrosion effect on pipelines. Therefore, the concentration of Cu2＋ should not be too high.