消除阻垢剂对碳酸钙结垢影响试验研究

Experimental Study on Eliminating the Influence of Scale Inhibitors on Calcium Carbonate

为了提高高盐废水反渗透脱盐过程中的浓水回收率,降低反渗透成本,可以先去除浓缩液中高浓度成垢离子,再将处理后的浓缩液进行循环利用。通过电导率法研究了阻垢剂作用下碳酸钙结垢规律,并进一步研究了消除阻垢剂影响的方法。结果表明,10mg/L MDC220阻垢剂对碳酸钙沉淀具有明显的阻垢效果。通气条件下,在"阻垢剂-CaCl2-Na2CO3"体系中投加双十二烷基二甲基溴化铵(DDAB)或者MgO,可以显著消除阻垢剂对碳酸钙的结垢影响,且相同投加量下DDAB对阻垢剂的消除作用优于MgO。试验条件下,最优阻垢剂消除药剂为20mg/L DDAB,最优通气时间为30min,最优空气流量为0.2m3/h。

In order to increase the recovery rate of concentrated water and reduce the cost in the process of reverse osmosis desalting of high-salt wastewater,the high concentration scaling ions in the concentrated liquid could be removed first,and then the treated concentrated liquid could be recycled.In this paper the scaling regularity of calcium carbonate under the action of scale inhibitor was studied by conductivity method,and the approaches to eliminate the effect of scale inhibitor were further explored.Results showed that 10 mg/L MDC220 had obvious scale inhibition effect on calcium carbonate precipitation.In the scale inhibitor-CaCl2-Na2CO3 system,adding DDAB or MgO under aeration condition could obviously eliminate the effect of scale inhibitor on calcium carbonate scale.The effect of DDAB on eliminating scale inhibitor was better than that of MgO under the same dosage.In this experiment,the optimum scale inhibitor eliminating agent was 20 mg/L DDAB,the optimal ventilation time was 30 min,and the optimum air flow rate was 0.2 m3/h.