Université Paris-Saclay, INRAE, AgroParisTech, UMR SayFood, 91300, Massy, France.
Conservatoire National des Arts et Métiers, 75003, Paris, France.
Environ Sci Pollut Res Int. 2020 Dec;27(34):42685-42703. doi: 10.1007/s11356-020-10160-0. Epub 2020 Jul 26.
The food industry consumes large amounts of clean, potable water and in turn generates a significant amount of wastewater. In order to minimize water consumption, membrane technologies represent a suitable solution for the treatment of wastewater before it is recycled as process water. Many studies have shown the effectiveness of this technology in the dairy industry, but there are few studies in the fruit- and vegetable-processing sectors. A recently developed methodology for the reduction of water consumption was tested here. Compounds to be eliminated were identified through chemical analysis of several wastewater samples from a carrot-peeling process. Drinking-water quality was selected as our target. Total suspended solids (TSS), fructose, glucose and sucrose were identified as key parameters. Salts (particularly Ca and Mg), pH and carbonate hardness (CH) were identified as indicators for evaluating the risk of scaling and corrosion. Based on these results, sieving followed by a 0.5-μm microfiltration (MF) was chosen as the process for pre-treatment. Four nanofiltration (NF) membranes (NFW from SYNDER, DK from GE, NF270 from DOW and SR3D from KOCH) and three reverse osmosis (RO) membranes (ESPA4 from Nitto Group Company, BW30 from DOW and HRX from KOCH) were then tested for the capacity to minimize chemical oxygen demand (COD) and to principally remove sugars. These membranes were then evaluated in terms of permeability and rejection rates. High-quality water could be obtained with RO membranes at low pressure (up to 15 bar) while limiting fouling risks. Rejection rates up to 98.3, 98.0, 99.2, 99.2 and 99.4% for conductivity, COD, fructose, glucose and sucrose, respectively, were achieved. These results are very encouraging for future reuse in vegetable processing before the blanching step, after an additional disinfection treatment.
食品工业消耗大量清洁、可饮用水，同时产生大量废水。为了最大限度地减少用水量，膜技术是处理废水并将其回收再利用为工艺用水的合适解决方案。许多研究已经表明，这种技术在乳制品行业非常有效，但在水果和蔬菜加工行业的研究很少。本文中测试了一种最近开发的减少耗水量的方法。通过对胡萝卜去皮过程中的几个废水样本进行化学分析，确定了要去除的化合物。饮用水质量被选为我们的目标。总悬浮固体（TSS）、果糖、葡萄糖和蔗糖被确定为关键参数。盐（特别是 Ca 和 Mg）、pH 值和碳酸盐硬度（CH）被确定为评估结垢和腐蚀风险的指标。基于这些结果，选择了筛分后进行 0.5-μm 微滤（MF）作为预处理工艺。然后测试了四种纳滤（NF）膜（SYNDER 的 NFW、GE 的 DK、DOW 的 NF270 和 KOCH 的 SR3D）和三种反渗透（RO）膜（Nitto Group Company 的 ESPA4、DOW 的 BW30 和 KOCH 的 HRX），以评估它们去除 COD 和主要去除糖的能力。然后根据渗透性和截留率对这些膜进行评估。RO 膜在低压（高达 15 巴）下可获得高质量的水，同时限制结垢风险。对电导率、COD、果糖、葡萄糖和蔗糖的截留率分别达到 98.3%、98.0%、99.2%、99.2%和 99.4%。这些结果对于在烫漂步骤之前的蔬菜加工中的未来再利用非常有希望，在进行额外的消毒处理之后。
