Suchergebnisse

During evaporation, the loss of sucrose can occur due to acid-catalysed hydrolysis to glucose and fructose, a reaction that is exponential with temperature. This paper reviews non-thermal methods for concentrating juices, mainly focusing on the developments of forward osmosis (FO) membranes for juice processing, detailing the benefits and limitations of this technology. A laboratory FO membrane was used in this preliminary study to concentrate pure sucrose solutions and clarified juice from ~10 to 45% rds using a calcium chloride draw solution. A small amount of reverse salt flux was observed.
The non-sucrose substances in factory juices had little impact on flux performance, with the flux reducing inversely with the volumetric concentration factor. By concentrating to a limit of 45% rds, concentration polarisation factors that can have a detrimental impact on the flux were not realised. Possible strategies were also explored for the integration into the sugar-manufacturing process.

Development of forward osmosis (FO) membranes became one of the alternative methods for drinking water supply in an emergency. In this research, drinking water bags based on FO membrane have been developed using chitosan as the basic material of membrane. The chitosan membrane used for the manufacture of drinking water bags has a thickness of 0.043 mm, 30.3% porosity, tensile strength 28.83 kgf / mm2, swelling degree 43.5% and elongation of 7.16%. Drinking water bags are made with a combination of Polypropylene Plastic (PP) and aluminum foil with FO membrane inside. This drinking water bag can be applied for brackish water purification to be energy drinking water as one of the solutions for the drinking water supply in emergencies. FO process testing is done by using variation of sugar solution as the draw solution, that are glucose, fructose, sucrose and mixture. The concentration of applied draw solution is 1, 2 and 3M within 1 hour treatment. The highest water flux was obtained in 3M sucrose solution with a flux value of 5.25 L/m2hour. The results of drinking water quality parameters analysis in the form of pH, Total Dissolve Solid (TDS), salinity, conductivity, heavy metals and Escherichia coli (E. coli) contents showed that the FO water produc meets drinking water quality standards based on Indonesian government regulation of drinking water quality. FO-membrane-based drinking water bags are potentially used as an alternative solution for the energy drinking water supply in an emergency.

AbstractA fertilizer drawn forward osmosis (FDFO) process was tested for the concentration of synthetic brine using an industrial-grade fertilizer ammonium sulfate (NH4)2SO4 as the draw solution (DS), NaCl-based synthetic brine as the feed solution (FS), and a commercial forward osmosis (FO) membrane. A bench-scale investigation and a pilot-scale investigation were carried out. By using the highest possible concentration of the DS with a fixed concentration of the FS, the brine generated by reverse osmosis (RO) desalination plants was simulated. The aim of this investigation, performed in batch mode, was to assess the feasibility of using the FDFO process with the tested DS to concentrate the brine by extracting water to dilute the DS. While the main aim of the investigated process was achieving the maximum possible volume reduction of the brine, the resulting DS was further diluted to reduce the nutrients' concentration in the diluted DS to the acceptable levels producing fertilized water that can be used for fertigation. The investigation showed that the proposed process using the tested fertilizer resulted in an average water flux of 8.01 l/h/m2, and a volume reduction of the brine of around 12%.

[EN] Forward osmosis is a low-energy water treatment emerging technology, which has demonstrated improved solute rejection and low fouling propensity. In this study, the applicability of aquaporin-based forward osmosis membranes during separation of biogas digestate liquid fractions was investigated. The results showed that Total Ammonia-Nitrogen rejection was higher than 95.5% in all experiments, independently of the type of draw solution (NaCl and hide preservation effluents), experimental period and the use of feed acidification. The results also confirmed that high draw osmotic pressures (i.e. 3.5¿M sodium chloride and hide preservation wastewater) combined with feed acidification had a negative effect on the membrane water permeability. Membrane rinsing after fouling was also successful in recovering the membrane initial water flux as well as removing the remaining foulants on the membrane surface. The membrane inspection results from Scanning-Electron Microscope, Energy-Dispersive X-Ray analysis and Fourier Transform Infrared¿Attenuated Total Reflectance showed that fouling in this application was mild and reversible after membrane rinsing. The applicability of aquaporin-based forward osmosis membranes during separation of biogas digestate liquid fractions has been demonstrated. The results showed the potential of this technology to achieve enhanced ammonia-nitrogen rejections and low-fouling propensity. ; The authors thank the tannery factory in the region of Murcia (Spain) for providing the wastewater samples as well as Depuración de Aguas del Mediterráneo (DAM, Spain) for funding the forward osmosis project. Thanks to August Bonmatí from IRTA GIRO Joint Research Unit IRTA-UPC, for providing the digestate liquid fractions, to Rebeca Vidal-Pérez as student assistant during the chemical analysis and to the Electron Microscopy Service from the Polytechnic University of Valencia (UPV, Spain). The authors further acknowledge funding from People Programme (Marie Curie Actions) of the European Union Seventh ...

Human urine is a unique solution that has the right composition to constitute both a severe environmental threat and a rich source of nitrogen and phosphorous. In fact, between 4-9% of urine mass consists of ions, such as K+, Cl-, Na+ or NH4+. Because of its high ionic strength, urine osmotic pressure can reach values of up to 2000 kPa. With this in mind, this work aimed to study the effectiveness of real urine as a novel draw solution for forward osmosis. Water flux, reverse nitrogen flux and membrane fouling were investigated using fresh or hydrolysed urine. Water flux as high as 16.7 ± 1.1 L.m-2. h-1 was recorded using real hydrolysed urine. Additionally, no support layer membrane fouling was noticed in over 20 hours of experimentation. Urine was also employed to dewater a Chlorella vulgaris culture. A fourfold increase in algal concentration was achieved while having an average flux of 14.1 L.m-2. h-1. During the algae dewatering, a flux decrease of about 19% was noticed; this was mainly due to a thin layer of algal deposition on the active side of the membrane. Overall, human urine was found to be an effective draw solution for forward osmosis. ; This research was supported by the National Research Foundation of Korean Grant funded by the Korean Government (MSIP) (No. NRF-2015R1A5A7037825) and by the Australian Research Council through Future Fellowship (FT140101208). HY and CL are grateful for the support of the Korea Institute of Energy Technology Evaluation and Planning (KETEP) through the "Human Resources Program in Energy Technology" project (No. 20164030201010) funded by the Ministry of Trade, Industry and Energy, Republic of Korea.