Scale-Up of Membrane-Based Zinc Recovery from Spent Pickling Acids of Hot-Dip Galvanizing

Zinc recovery from spent pickling acids (SPAs) can play an important role in achieving a circular economy in the galvanizing industry. This work evaluates the scale-up of membrane-based solvent extraction technology aimed at the selective separation of zinc from industrial SPAs as a purification step prior to zinc electrowinning (EW). The experiments were carried out at a pilot scale treating SPAs batches of 57 to 91 L in a non-dispersive solvent extraction (NDSX) configuration that simultaneously performed the extraction and backextraction steps. The pilot plant was equipped with four hollow fiber contactors and 80 m2 of total membrane area, which was approximately 30 times higher than previous bench-scale studies. Tributylphosphate diluted in Shellsol D70 and tap water were used as organic and stripping agents, respectively. Starting with SPAs with high Zn (71.7 ± 4.3 g·L−1) and Fe (82.9 ± 5.0 g·L−1) content, the NDSX process achieved a stripping phase with 55.7 g Zn·L−1 and only 3.2 g Fe·L−1. Other minor metals were not transferred, providing the purified zinc stripping with better quality for the next EW step. A series of five consecutive pilot-scale experiments showed the reproducibility of results, which is an indicator of the stability of the organic extractant and its adequate regeneration in the NDSX operation. Zinc mass transfer fluxes were successfully correlated to zinc concentration in the feed SPA phase, together with data extracted from previous laboratory-scale experiments, allowing us to obtain the design parameter that will enable the leap to the industrial scale. Therefore, the results herein presented demonstrate the NDSX technology in an industrially relevant environment equivalent to TRL 6, which is an essential progress to increase zinc metal resources in the galvanizing sector.

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Synergistic Effect in Solvent Extraction—Effect of the Chelating Ligands on the Stability of Lutetium Mixed Chelates with β-Diketones and Their Adducts with TOPO—

Bulletin of the Chemical Society of Japan ◽

10.1246/bcsj.43.796 ◽

1970 ◽

Vol 43 (3) ◽

pp. 796-800 ◽

Cited By ~ 9

Author(s):

Tsunenobu Shigematsu ◽

Takaharu Honjyo

Keyword(s):

Solvent Extraction ◽

Synergistic Effect ◽

Chelating Ligands ◽

The Stability

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Pilot-Scale Production of Chito-Oligosaccharides Using an Innovative Recombinant Chitosanase Preparation Approach

Polymers ◽

10.3390/polym13020290 ◽

2021 ◽

Vol 13 (2) ◽

pp. 290

Author(s):

Chih-Yu Cheng ◽

Chia-Huang Tsai ◽

Pei-Jyun Liou ◽

Chi-Hang Wang

Keyword(s):

Cell Density ◽

Scale Up ◽

Cost Effective ◽

Pilot Scale ◽

Ionic Concentration ◽

Dihydrogen Phosphate ◽

Scale Production ◽

Sodium Dihydrogen Phosphate ◽

Selective Precipitation ◽

Pilot Scale Production

For pilot-scale production of chito-oligosaccharides, it must be cost-effective to prepare designable recombinant chitosanase. Herein, an efficient method for preparing recombinant Bacillus chitosanase from Escherichia coli by elimination of undesirable substances as a precipitate is proposed. After an optimized culture with IPTG (Isopropyl β-d-1-thiogalactopyranoside) induction, the harvested cells were resuspended, disrupted by sonication, divided by selective precipitation, and stored using the same solution conditions. Several factors involved in these procedures, including ion types, ionic concentration, pH, and bacterial cell density, were examined. The optimal conditions were inferred to be pH = 4.5, 300 mM sodium dihydrogen phosphate, and cell density below 1011 cells/mL. Finally, recombinant chitosanase was purified to >70% homogeneity with an activity recovery and enzyme yield of 90% and 106 mg/L, respectively. When 10 L of 5% chitosan was hydrolyzed with 2500 units of chitosanase at ambient temperature for 72 h, hydrolyzed products having molar masses of 833 ± 222 g/mol with multiple degrees of polymerization (chito-dimer to tetramer) were obtained. This work provided an economical and eco-friendly preparation of recombinant chitosanase to scale up the hydrolysis of chitosan towards tailored oligosaccharides in the near future.

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Status Update on Bioelectrochemical Systems: Prospects for Carbon Electrode Design and Scale-Up

Catalysts ◽

10.3390/catal11020278 ◽

2021 ◽

Vol 11 (2) ◽

pp. 278

Author(s):

Katharina Herkendell

Keyword(s):

Gradual Increase ◽

Scale Up ◽

Value Added ◽

Biofuel Cells ◽

Carbon Electrode ◽

Electrode Design ◽

Bioelectrochemical Systems ◽

Electrode Assemblies ◽

The Stability ◽

Scientific Attention

Bioelectrochemical systems (BES) employ enzymes, subcellular structures or whole electroactive microorganisms as biocatalysts for energy conversion purposes, such as the electrosynthesis of value-added chemicals and power generation in biofuel cells. From a bioelectrode engineering viewpoint, customizable nanostructured carbonaceous matrices have recently received considerable scientific attention as promising electrode supports due to their unique properties attractive to bioelectronics devices. This review demonstrates the latest advances in the application of nano- and micro-structured carbon electrode assemblies in BES. Specifically, in view of the gradual increase in the commercial applicability of these systems, we aim to address the stability and scalability of different BES designs and to highlight their potential roles in a circular bioeconomy.

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Optimization of process parameters for naringinase production by Aspergillus tubingensis UA13 and pilot scale-up study

Preparative Biochemistry & Biotechnology ◽

10.1080/10826068.2021.1925914 ◽

2021 ◽

pp. 1-8

Author(s):

Xin-Ke Xia ◽

Yuan-E. Zhang ◽

Sheng-Jiao Lei ◽

Biao Hu ◽

Cai-Xia Fu

Keyword(s):

Process Parameters ◽

Scale Up ◽

Pilot Scale ◽

Aspergillus Tubingensis ◽

Optimization Of Process Parameters ◽

Scale Up Study

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AN ADVANCED ADAPTIVE FINITE ELEMENT CODE APPLIED FOR COATING-SUBSTRATE SIMULATION

Journal of Multiscale Modelling ◽

10.1142/s1756973711000376 ◽

2011 ◽

Vol 03 (01n02) ◽

pp. 91-107 ◽

Cited By ~ 3

Author(s):

JÜRGEN LEOPOLD ◽

KATRIN HELLER ◽

ARNDT MEYER ◽

REINER WOHLGEMUTH

Keyword(s):

Finite Element ◽

Fe Simulation ◽

Scale Up ◽

Computational Time ◽

Adaptive Finite Element ◽

Workpiece Surface ◽

Coated Tools ◽

Geometrical Simulation ◽

The Stability ◽

And Storage

The stability of coating-substrate systems influences the chip formation and the surface integrity of the new generated workpiece surface, too. Using finite element (FE) simulation, deformations, strains and stresses in coated tools, caused by external and internal loads, can be computed on a microscopic scale. Since both, the whole macroscopic tool (in mm-scale) and the microscopic coating layers (in μm-scale up to nm-scale) must be included in the same geometrical simulation model, graded high-resolution FE meshes must be used. Nevertheless, the number of nodes in the 3D computational FE grid reaches some millions, leading to large computational time and storage requirements. For this reason, an advanced adaptive finite element (AAFEM) software has been developed and used for the simulation.

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Model-based evaluation of a new upgrading concept for N-removal

Water Science & Technology ◽

10.2166/wst.2002.0104 ◽

2002 ◽

Vol 45 (6) ◽

pp. 169-176 ◽

Cited By ~ 25

Author(s):

S. Salem ◽

D. Berends ◽

J.J. Heijnen ◽

M.C.M. van Loosdrecht

Keyword(s):

Mathematical Modelling ◽

Scale Up ◽

Treatment Plant ◽

Ammonia Concentration ◽

Pilot Scale ◽

Full Scale ◽

Model Based ◽

N Removal ◽

Quantitative Basis ◽

Treatment Concepts

Mathematical modelling is considered a time and cost-saving tool for evaluation of new wastewater treatment concepts. Modelling can help to bridge the gap between lab and full-scale application. Bio-augmentation can be used to obtain nitrification in activated sludge systems with a limited aerobic sludge retention time. In the present study the potential for augmenting the endogenous nitrifying population is evaluated. Implementing a nitrification reactor in the sludge return line fed with sludge liquor with a high ammonia concentration leads to augmentation of the native nitrifying population. Since the behaviour of nitrifiers is relatively well known, a choice was made to evaluate this new concept mainly based on mathematical modelling. As an example an existing treatment plant (wwtp Walcheren, The Netherlands) that needed to be upgraded was used. A mathematical model, based on the TUDP model and implemented in AQUASIM was developed and used to evaluate the potential of this bioaugmentation in the return sludge line. A comparison was made between bio-augmentation and extending the existing aeration basins and anoxic tanks. The results of both modified systems were compared to give a quantitative basis for evaluation of benefits gained from such a system. If the plant is upgraded by conventional extension it needs an increase in volume of about 225%; using a bioaugmentation in the return sludge line the total volume of the tanks needs to be expanded by only 75% (including the side stream tanks). Based on the modelling results a decision was made to implement the bioaugmentation concept at full scale without further pilot scale testing, thereby strongly decreasing the scale-up period for this process.

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Separation of virgin plastic polymers and post-consumer mixed plastic waste by sinking-flotation technique

10.21203/rs.3.rs-305340/v1 ◽

2021 ◽

Author(s):

Orlando Washinton Meneses Quelal ◽

Borja Velázquez-Martí ◽

Andrés Ferrer Gisbert

Keyword(s):

Sodium Chloride ◽

Municipal Solid Waste ◽

Solid Waste ◽

Tap Water ◽

Pilot Scale ◽

Complete Separation ◽

Plastic Waste ◽

High Density ◽

Low Density ◽

Flotation Technique

Abstract The main objective of this research is to separate virgin polymers (PA, PC, PP, HDPE; PS and ABS) and post-consumer plastic waste from municipal solid waste (MSW) using the sinking-flotation technique. The separation was carried out on a pilot scale in a container of 800 l of useful volume with agitation of 160 rpm for one hour. Tap water, ethanol solutions and sodium chloride at different concentrations were used as the densification medium. The virgin polymers were separated into two groups, that is, a group of low-density polymers (HDPE and PP) and a group of high-density polymers (PS, ABS, PA, and PC). Polymers whose density was less than that of the medium solution floated to the surface, while those whose density was greater than that of the medium solution sank to the bottom. The experimental results showed that the complete separation of HDPE from PP was achieved at 23% v/v of ethanol. For the separation of the high-density polymers, up to 40% w / v sodium chloride was used. The recoveries of the polymers ranged from 70 to 99.70%. In post-consumer recycled plastic waste, fractions of 29.6% polyolefins, 37.54% PS, 11% ABS, 8% PA and 12% PC, PET and PVC were obtained. Finally, cast plates were made of the post-consumer waste to improve the identification of the type of polymer present in the separated fractions.

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Evaluation of Fixed-Bed Cultures with Immobilized Lactococcus Lactis ssp. Lactis on Different Scales

The Open Biotechnology Journal ◽

10.2174/1874070701711010016 ◽

2017 ◽

Vol 11 (1) ◽

pp. 16-25 ◽

Cited By ~ 1

Author(s):

Rebecca Faschian ◽

Ilyas Eren ◽

Steven Minden ◽

Ralf Pörtner

Keyword(s):

Dilution Rate ◽

Lactococcus Lactis ◽

Scale Up ◽

Fixed Bed ◽

Pilot Scale ◽

Fixed Bed Reactor ◽

Batch Mode ◽

Promising Alternative ◽

Fixed Beds ◽

Pilot Scale Reactor

Fixed-bed processes, where cells are immobilized within macroporous carriers, are a promising alternative to processes with suspended cells. A scale-up concept is presented in order to evaluate the performance as part of process design of fixed-bed processes. Therefore,Lactococcus lactiscultivation in chemostat and batch mode was compared to fixed bed cultures on three different scales, the smallest being the downscaledMultifermwith 10 mL fixed bed units, the second a 100 mL fixed-bed reactor and the third a pilot scale reactor with 1 L fixed bed volume. As expected, the volume specific lactate productivity of all cultivations was dependent on dilution rate. In suspension chemostat culture a maximum of 2.3 g·L-1·h-1was reached. Due to cell retention in the fixed-beds, productivity increased up to 8.29 g·L-1·h-1at a dilution rate of D = 1.16 h-1(corresponding to 2.4·µmax) on pilot scale. For all fixed bed cultures a common spline was obtained indicating a good scale-up performance.

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