Research on calcium carbonate scale inhibition of combination of polyaspartic acid and sodium lignosulfonate

Research has been done on the scale inhibition properties of CaCO3 for concentration of polyaspartic acid(PASP) and sodium lignosulfonate(SLS) with the static test.Results indicated that the rate of scale inhibition was close to 100 percents when the concentration of PASP was 5.0mg/L,the rate of scale inhibition was incline to stable when the concentration of SLS was up to 300mg/L,but the rate of scale inhibition was down to 70 percents when its concentration was 600mg/L.To reduce the cost of PASP and improve the rivalrousness with the phosphorus water-treatment reagents,the combination system of PASP with SLS has been developed,simultaneously the effects of Ca2+ concentration,temperature,pH,and time on the rate of scale inhibition were evaluated.Results indicated that the rate of scale inhibition of combination(PASP 2.0mg/L + SLS 5.0mg/L) was close to 100 percents.It also indicated that the combination system could be used in water system with high Ca2+,high pH and could stay long time in water system of high temperature.Considering from economical benefit and scale inhibition properties,the combination system has good scale inhibition properties.