Specific energy requirement of direct contact membrane distillation

Abstract In the present work, the performance of different cell designs used for the membrane distillation (MD) process was investigated. Three distinctive cell designs were proposed and compared. A numerical simulation using ANSYS Fluent 19 was used to study the performance of the cells. The effects of changing inlet Reynolds number on pressure drop, salt concentration and velocity contours with in the different cell deigns were investigated. Results show that the pressure drop is minimum across the first design, and the salt concentration decreases as Reynolds number increases. At Reynolds number = 125, the results show an enhanced velocity distribution compared to Reynolds number = 250 and 50. One of the proposed cell designs was then fabricated to study the effect of fluid flow on the performance in a direct contact membrane distillation system. Energy parameters were calculated to evaluate the performance of the cell. An evacuated tube solar collector was used to provide the system with hot water. System thermal efficiency, gained output ratio, and specific energy consumption analysis were performed for the system. The increase in the feed flow rate almost doubled the system thermal efficiency and the gained output ratio was increased from 0.31 to 0.60, while the specific energy consumption decreased from 2064 to 1037 kWh/m3.

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Energetic relationships for crushing of soil clods

Progress in Agricultural Engineering Sciences ◽

10.1556/progress.2.2006.1.3 ◽

2006 ◽

Vol 2 (1) ◽

pp. 51-72

Author(s):

István Patay ◽

Virág Sándor

Keyword(s):

Moisture Content ◽

Specific Energy ◽

Soil Moisture Content ◽

Energy Requirement ◽

Clay Content ◽

Clay Soils ◽

Rigid Support ◽

Soil Plasticity ◽

Specific Energy Requirement ◽

The Relationship

Clod crushing is a principal problem with soils of high clay content. Therefore, there is a need for determining the conditions for clod breaking and clod crushing. The objective of the work was to develop a special purpose tool for single clod breaking both by rigid support of the clod and by a single clod supported by soil and to develop a machine for clod crushing. Furthermore, the purpose was to determine the relationship between the specific energy requirement for clod crushing in the function of soil plasticity and the soil moisture content by the means of the developed tool and machine. The main result of the experiments is summarized in a 3D diagram where the specific energy requirement for soil clod crushing is given in the function of the moisture content and the plasticity index for different clay soils.

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Omniphobic palygorskite coated Janus membrane with enhanced fouling and wetting resistance for direct contact membrane distillation

Desalination ◽

10.1016/j.desal.2021.114986 ◽

2021 ◽

Vol 505 ◽

pp. 114986

Author(s):

Jiahui Zhang ◽

Nan Li ◽

Dong Wang ◽

Jinmei Li ◽

Yue Chen ◽

...

Keyword(s):

Direct Contact ◽

Membrane Distillation ◽

Direct Contact Membrane Distillation

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Corrigendum to “Preparation and characterization of PVDF flat-sheet membranes for direct contact membrane distillation” [Sep. Purif. Technol. 135 (2014) 211–222]

Separation and Purification Technology ◽

10.1016/j.seppur.2021.119197 ◽

2021 ◽

pp. 119197

Author(s):

Deyin Hou ◽

Hua Fan ◽

Qinliang Jiang ◽

Jun Wang ◽

Xiaohui Zhang

Keyword(s):

Direct Contact ◽

Membrane Distillation ◽

Direct Contact Membrane Distillation ◽

Flat Sheet

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Concentration of Bioactive Phenolic Compounds in Olive Mill Wastewater by Direct Contact Membrane Distillation

Molecules ◽

10.3390/molecules26061808 ◽

2021 ◽

Vol 26 (6) ◽

pp. 1808

Author(s):

Rosa Tundis ◽

Carmela Conidi ◽

Monica R. Loizzo ◽

Vincenzo Sicari ◽

Rosa Romeo ◽

...

Keyword(s):

Direct Contact ◽

High Performance ◽

Biological Properties ◽

Membrane Distillation ◽

Olive Mill Wastewater ◽

High Concentration ◽

Direct Contact Membrane Distillation ◽

Reducing Activity ◽

Β Carotene ◽

Olive Mill

Olive mill wastewater (OMW), generated as a by-product of olive oil production, is considered one of the most polluting effluents produced by the agro-food industry, due to its high concentration of organic matter and nutrients. However, OMW is rich in several polyphenols, representing compounds with remarkable biological properties. This study aimed to analyze the chemical profile as well as the antioxidant and anti-obesity properties of concentrated fractions obtained from microfiltered OMW treated by direct contact membrane distillation (DCMD). Ultra-high performance liquid chromatography (UHPLC) analyses were applied to quantify some phenols selected as phytochemical markers. Moreover, α-Amylase, α-glucosidase, and lipase inhibitory activity were investigated together with the antioxidant activity by means of assays, namely β-carotene bleaching, 2,2′-azino-bis(3-ethylbenzothiazoline-6-sulphonic) acid (ABTS) diammonium salts, 2,2-diphenyl-1-picrylhydrazyl (DPPH) assay, and Ferric Reducing Activity Power (FRAP) tests. MD retentate—which has content of about five times greater of hydroxytyrosol and verbascoside and about 7 times greater of oleuropein than the feed—was more active as an antioxidant in all applied assays. Of interest is the result obtained in the DPPH test (an inhibitory concentration 50% (IC50) of 9.8 μg/mL in comparison to the feed (IC50 of 97.2 μg/mL)) and in the ABTS assay (an IC50 of 0.4 μg/mL in comparison to the feed (IC50 of 1.2 μg/mL)).

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