Lactose-free milk production generates large volumes of a by-product, rich in lactose, known as nanofiltration retentate (NFR). However, enhancing the value of this by-product is challenging due to the presence of high concentration of minerals which are believed to induce a salty and bitter taste. To overcome this issue, the present project aims to study the feasibility of an electrodialysis (ED) process for demineralization of NFR. In addition to native NFR, two subsequent dilutions of NFR were tested reducing the electric conductivity from 5.5 ± 0.2 to 4.7 ± 0.3 and 3.7 ± 0.1 mS·cm⁻¹ while three voltages of 5, 10 and 15 V during ED were applied. The ED efficiency was measured in terms of demineralization rate, mineral removal kinetics, system resistance and energy consumption during the process. A demineralization level higher than 90% was reached within 120 min without significant loss of lactose. But, total nitrogen content was lost to some extent. The demineralization rate and energy consumption increased with the applied potential, where the demineralization efficiency declined significantly after 80% for all processing conditions. A predictive model was therefore developed to estimate the time required for 80% of demineralization as a function of initial conductivity and voltage applied.

无乳糖牛奶生产会产生大量富含乳糖的副产物，称为纳滤滞留物（NFR）。然而，由于高浓度的矿物质的存在，增加这种副产物的价值是具有挑战性的，据信这些矿物质会引起咸味和苦味。为克服此问题，本项目旨在研究电渗析（ED）工艺用于NFR脱盐的可行性。除天然NFR外，还测试了NFR的两个后续稀释液，将电导率从5.5±0.2降至4.7±0.3和3.7±0.1 mS·cm ^-1ED期间施加了5 V，10 V和15 V的三个电压。ED效率是根据过程中的脱盐率，除矿动力学，系统阻力和能耗来衡量的。在120分钟内达到的脱矿物质含量高于90％，而乳糖却没有明显损失。但是，总氮含量在一定程度上损失了。脱盐率和能耗随施加的电位而增加，在所有工艺条件下，脱盐效率均在80％之后显着下降。因此，开发了一种预测模型，以估算80％脱盐所需的时间，该时间是初始电导率和施加电压的函数。