Thin Beet Juice Concentration With Membrane Distillation
(2026) METM01 20261Chemical Engineering (M.Sc.Eng.)
- Abstract
- This thesis investigates vacuum membrane distillation (VMD) as an energy-efficient method for concentrating thin beet sugar juice. It evaluates the effects of operating conditions on concentration performance, membrane selectivity, product quality, and process stability.
Pilot-scale experiments were conducted using 5000 mL of thin beet sugar juice at each batch. The system was operated at varying temperatures of 70, 75, and 80 °C, vacuum pressures of 27, 95, and 105 mbar, and feed flow rates of 6.7, 8.4, and 12.8 L/min. Two ceramic membrane configurations were evaluated: a 7-channel membrane (0.156 m²) and a 19-channel membrane (0.222 m²).
The 7-channel membrane was limited to 70 °C because of severe concentration polarization. Under... (More) - This thesis investigates vacuum membrane distillation (VMD) as an energy-efficient method for concentrating thin beet sugar juice. It evaluates the effects of operating conditions on concentration performance, membrane selectivity, product quality, and process stability.
Pilot-scale experiments were conducted using 5000 mL of thin beet sugar juice at each batch. The system was operated at varying temperatures of 70, 75, and 80 °C, vacuum pressures of 27, 95, and 105 mbar, and feed flow rates of 6.7, 8.4, and 12.8 L/min. Two ceramic membrane configurations were evaluated: a 7-channel membrane (0.156 m²) and a 19-channel membrane (0.222 m²).
The 7-channel membrane was limited to 70 °C because of severe concentration polarization. Under these conditions, the juice concentration reached 9.10 °Brix after 3 hours at a 6 hour run. The 19-channel membrane showed better performance under optimal hydrodynamic conditions of 75 °C, 95 mbar, and 8.4 L/min. At this condition, thin juice was concentrated from 11.80 to 15.54 °Brix after 3 hours. The juice quality was maintained above 90 %, with acceptable colour levels in the range of 2707 to 3027 ICUMSA. The improved performance attributes to a higher membrane surface-area to volume ratio at a Reynolds number of 1795 within the laminar flow regime.
The membrane maintained high selectivity throughout the experiments achieving low permeate conductivity, an average flux of 1.41 L/m²·h, and 96.11% ion retention. These results demonstrate efficient water removal and stable process performance. Despite fouling and scaling, the cleaning protocol successfully restored 98% of the membrane performance. The recovery on performance of the membrane after cleaning highlights the robustness of ceramic membranes for VMD applications.
Furthermore, the 19-channel membrane provided the best overall performance under the tested conditions. This highlights the potential of VMD to effectively concentrate thin beet sugar juice. These findings indicate that VMD has potential for integration into sugar factories, particularly when combined with low-grade waste heat. However, further process optimization, long-term testing, and improved membrane and module designs are required before industrial-scale implementation. (Less) - Popular Abstract
- Beet juice contains a lot of water that must be removed during sugar production. This step requires large amounts of energy and is one of the most energy-intensive stages in the process. However, high temperatures are typically used to evaporate the water, which can also affect the juice quality.
Although the Swedish sugar industry is already energy efficient, further reductions in energy use are required to achieve climate-neutral sugar production by 2050. To reduce the energy demand, researchers are investigating membrane technologies as alternatives to conventional evaporation. While some membrane methods have been successful in other food industries, they have shown limited performance for beet juice due to sugar losses, membrane... (More) - Beet juice contains a lot of water that must be removed during sugar production. This step requires large amounts of energy and is one of the most energy-intensive stages in the process. However, high temperatures are typically used to evaporate the water, which can also affect the juice quality.
Although the Swedish sugar industry is already energy efficient, further reductions in energy use are required to achieve climate-neutral sugar production by 2050. To reduce the energy demand, researchers are investigating membrane technologies as alternatives to conventional evaporation. While some membrane methods have been successful in other food industries, they have shown limited performance for beet juice due to sugar losses, membrane fouling, and high pressure requirements.
One promising alternative is vacuum membrane distillation (VMD). In this process, the juice is gently heated and water vapour passes through a water-repellent barrier under vacuum conditions. This removes water while retaining sugar and other valuable compounds.
A collaborative study between Nordic Sugar AB and Lund University tested a VMD systems using thin beet juice from the Ortofta sugar mill. The results showed that VMD can efficiently concentrate beet juice while preserving its valuable components. Both experimental and theoretical studies suggest that the technology can reduce energy use and lower the heat requirement for sugar production.
VMD has the potential to improve energy efficiency and support more sustainable sugar production. It could also enable the use of low-grade or waste heat within sugar factories. However, the process still has relatively low water-removal rates, and further optimization and industrial-scale testing are needed before large-scale implementation. Despite these challenges, VMD shows strong potential to contribute to sustainable sugar production. (Less)
Please use this url to cite or link to this publication:
https://lup.lub.lu.se/student-papers/record/9247249
- author
- Awak, David Etido LU
- supervisor
- organization
- alternative title
- Vacuum Membrane Distillation for concentration of Thin Beet SugarJuice in Swedish Beet Sugar Refining
- course
- METM01 20261
- year
- 2026
- type
- H2 - Master's Degree (Two Years)
- subject
- keywords
- Vacuum Membrane Distillation (VMD), Ceramic Membranes, Thin Beet Sugar Juice, Concentration Polarization, Membrane Fouling, Internal Pore Scaling, Sugar Concentration, Process Optimization, Membrane Technology
- language
- English
- id
- 9247249
- date added to LUP
- 2026-08-24 11:41:43
- date last changed
- 2026-08-24 11:41:43
@misc{9247249,
abstract = {{This thesis investigates vacuum membrane distillation (VMD) as an energy-efficient method for concentrating thin beet sugar juice. It evaluates the effects of operating conditions on concentration performance, membrane selectivity, product quality, and process stability.
Pilot-scale experiments were conducted using 5000 mL of thin beet sugar juice at each batch. The system was operated at varying temperatures of 70, 75, and 80 °C, vacuum pressures of 27, 95, and 105 mbar, and feed flow rates of 6.7, 8.4, and 12.8 L/min. Two ceramic membrane configurations were evaluated: a 7-channel membrane (0.156 m²) and a 19-channel membrane (0.222 m²).
The 7-channel membrane was limited to 70 °C because of severe concentration polarization. Under these conditions, the juice concentration reached 9.10 °Brix after 3 hours at a 6 hour run. The 19-channel membrane showed better performance under optimal hydrodynamic conditions of 75 °C, 95 mbar, and 8.4 L/min. At this condition, thin juice was concentrated from 11.80 to 15.54 °Brix after 3 hours. The juice quality was maintained above 90 %, with acceptable colour levels in the range of 2707 to 3027 ICUMSA. The improved performance attributes to a higher membrane surface-area to volume ratio at a Reynolds number of 1795 within the laminar flow regime.
The membrane maintained high selectivity throughout the experiments achieving low permeate conductivity, an average flux of 1.41 L/m²·h, and 96.11% ion retention. These results demonstrate efficient water removal and stable process performance. Despite fouling and scaling, the cleaning protocol successfully restored 98% of the membrane performance. The recovery on performance of the membrane after cleaning highlights the robustness of ceramic membranes for VMD applications.
Furthermore, the 19-channel membrane provided the best overall performance under the tested conditions. This highlights the potential of VMD to effectively concentrate thin beet sugar juice. These findings indicate that VMD has potential for integration into sugar factories, particularly when combined with low-grade waste heat. However, further process optimization, long-term testing, and improved membrane and module designs are required before industrial-scale implementation.}},
author = {{Awak, David Etido}},
language = {{eng}},
note = {{Student Paper}},
title = {{Thin Beet Juice Concentration With Membrane Distillation}},
year = {{2026}},
}