Apple Juice, Manure and Whey Concentration with Forward Osmosis Using Electrospun Supported Thin-Film Composite Membranes

Abstract

Forward osmosis (FO), using the osmotic pressure difference over a membrane to remove water, can treat highly foul streams and can reach high concentration factors. In this work, electrospun TFC membranes with a very porous open support (porosity: 82.3%; mean flow pore size: 2.9 µm), a dense PA-separating layer (thickness: 0.63 µm) covalently attached to the support and, at 0.29 g/L, having a very low specific reverse salt flux (4 to 12 times lower than commercial membranes) are developed, and their FO performance for the concentration of apple juice, manure and whey is evaluated. Apple juice is a low-fouling feed. Manure concentration fouls the membrane, but this results in only a small decrease in overall water flux. Whey concentration results in instantaneous, very severe fouling and flux decline (especially at high DS concentrations) due to protein salting-out effects in the boundary layer of the membrane, causing a high drag force resulting in lower water flux. For all streams, concentration factors of approximately two can be obtained, which is realistic for industrial applications.

Advances in Membrane Separation for Biomaterial Dewatering

“…A critical challenge is that biobased materials often contain large quantities of water (50–98%). − Biomaterials are materials derived from land-based and aquatic plants, animals, bacteria, and fungi . Their large moisture content makes transport and processing cost- and energy-intensive, making efficient dewatering an essential unit operation in biorefineries. , Yet, traditional dewatering techniques based on thermal or chemical drying are thermodynamically inefficient and, currently, account for 15% of the energy consumed in industry. ,, Moreover, these techniques can negatively affect the product quality. , Dewatering through membrane separation will provide an energy-efficient alternative and has therefore gained a lot of attention in recent years. − …”

“… 5 Their large moisture content makes transport and processing cost- and energy-intensive, making efficient dewatering an essential unit operation in biorefineries. 6 , 7 Yet, traditional dewatering techniques based on thermal or chemical drying are thermodynamically inefficient and, currently, account for 15% of the energy consumed in industry. 2 , 3 , 8 Moreover, these techniques can negatively affect the product quality.…”

Green and Sustainable Forward Osmosis Process for the Concentration of Apple Juice Using Sodium Lactate as Draw Solution

“…Typically, apple juice is extracted by pressing or squeezing from the fresh fruits to extract vitamins, minerals and other beneficial components. Meanwhile, it is necessary to perform dehydration and concentration treatment to ensure the stability of juice and to minimize the cost of the packaging, preservation and transportation of the product [3]. There are several technologies for apple juice concentration, including vacuum evaporation (VE) concentration, freeze concentration, and vacuum freeze concentration [4,5].…”

Forward Osmosis for Metal Processing Effluents under Similar Osmotic Pressure Gradients

“…In many studies dealing with FO operating variables on real or synthetic feeds [ 20 , 21 , 22 , 23 , 24 , 25 , 26 , 27 , 28 , 29 , 30 , 31 ], concentration, or a proxy for concentration (permeate volume, concentration factor), was used instead of osmotic pressure gradient which obfuscates the impact of variable changes with osmotic pressure changes on kinetics. In the few cases where the osmotic pressure gradient was used [ 32 , 33 , 34 ] with real feeds, few operating variables were investigated, and they tested low osmotic pressure feeds (less than 20 bar). To assess the impact of an operating variable on FO performance for any feed, it is necessary to evaluate the above operating variables under similar bulk osmotic pressure gradients, or else it is impossible to separate the effect of the variable from the driving force.…”