Recovery of Nutrients from Wastewater via Electrodialysis

The need to treat wastewater in a sustainable way to minimalize contamination and maximize the recovery of nutrients is widelyrecognized. The focus is mainly on the removal and recovery of nutrients because of eutrophication problems in receiving waters,limitations of mining resources and high costs affiliated with nutrient production. Removal of nutrients is also a growing problemfor water authorities, as authorities often tighten standards of discharged waters to avoid unnecessary discharge of nutrients intowater bodies.The universally used technologies for nitrogen and phosphorus removal involve biological nitrification and denitrification and metalsalt precipitation. However, applying these technologies nutrients are made unrecoverable for fertilizing. Electrodialysis (ED) isa membrane process capable of concentrating and separating ions from wastewater. Thanks to the applied current, the migration ofions occurs, and ions are concentrated in the concentrate solution. Laboratory scale ED showed the potential of nutrient recoveryfrom wastewater sources.In this study, nutrients were recovered in concentrate solution from wastewater sludge liquid discharge by using electrodialysis.Calcium and sodium values in concentrated solution increased 10 times, values of potassium and chloride 5 times. The amount ofammonia nitrogen raised from 60 mg/l to 1700 mg/l. The concentrate enriched by nutrients may be used in further processes, e.g.phosphorus and ammonia nitrogen can be precipitated into the form of struvite.

Optimization of Vapor Diffusion Conditions for Anti-CD20 Crystallization and Scale-Up to Meso Batch

The crystal form is one of the preferred formulations for biotherapeutics, especially thanks to its ability to ensure high stability of the active ingredient. In addition, crystallization allows the recovery of a very pure drug, thus facilitating the manufacturing process. However, in many cases, crystallization is not trivial, and other formulations, such as the concentrate solution, represent the only choice. This is the case of anti-cluster of differentiation 20 (anti-CD20), which is one of the most sold antibodies for therapeutic uses. Here, we propose a set of optimized crystallization conditions for producing anti-CD20 needle-shaped crystals within 24 h in a very reproducible manner with high yield. High crystallization yield was obtained with high reproducibility using both hanging drop vapor diffusion and meso batch, which is a major step forward toward further scaling up the crystallization of anti-CD20. The influence of anti-CD20 storage conditions and the effect of different ions on the crystallization processes were also assessed. The crystal quality and the high yield allowed the first crystallographic investigation on anti-CD20, which positively confirmed the presence of the antibody in the crystals.

The application of fractional derivatives through Riemannliouville approach to xanthan gum viscoelasticity

Fractional derivatives are derivative with non-integer order, one of which is used for mathematical modeling of viscoelasticity. In this research, the fractional derivative was used to obtain a mathematical model of viscoelasticity. The method used was a fractional derivative through the Riemann-Liouville approach. The mathematical model of viscoelasticity obtained was a complex modulus consisting of storage and loss modulus. This model was applied to xanthan gum concentrate solution 0.5%, 1.0%, 2.0%, 3.0%, and 4.0% with simplified model parameters. The results obtained that the storage and loss modulus increased with increasing concentration of the solution. In addition, the modulus storage was always greater than the modulus loss for all concentrations of the solution. This suggests that the elastic properties of the xanthan gum solution are more dominant than their viscosity properties for all concentrations. Therefore, the viscoelasticity model using Riemann-Liouville fractional derivatives has a good ability to investigate the viscoelasticity behavior of all xanthan gum concentrations.

ФАРМАКО–ТОКСИКОЛОГІЧНА ОЦІНКА ПРЕПАРАТУ «ЦИФЛУР»

The results of pharmaco–toxicological evaluation insectoacaricid preparation «Tsiflur», in particular the study of locally irritating effect of the drug on the skin and mucous membranes of rabbits eyes. The preparation «Tsiflur» – representative of synth pyrethroids, in its composition has the active ingredient cyfluthrin, production NPF «Brovafarma». According to the manufacturer's instructions, the preparation recommended for the control of flying midges and other representatives akaroentomofauny that have veterinary importance. The tool is a clear oily solution of a yellowish color.Experimental studies were conducted on rabbits analogues in several stages. In the first phase we studied local irritant effect of the preparation in varying degrees of dilution when applied to intact skin of rabbits. The aim of the second stage of the research was to determine the local irritant effect of the d preparation on the mucous membrane of the eyes of rabbits.It has been established that the preparation «Tsiflur» in the test concentration (1: 100, 1: 200, 1: 400 concentrate solution) during the observation period did not show locally irritating effects in a single application to the intact areas of the skin of rabbits. Monitoring the bellies of the experiment showed no redness, swelling, thickening of the skin folds and the pain response to palpation place application of the preparation. Not set also signs of toxic effects of native preparation «Tsiflur», when applied under similar conditions. The reaction of the skin of animals per application experimental preparation was valued at 0 points. In the study of the preparation in a similar concentration on the possibility of providing local irritant effect on the mucous membrane of the eyes of rabbits determined that the native application of the preparation led to the emergence of a slight reddening of the eye mucosa and the appearance of watery eyes. These symptoms disappear without any intervention on the second day of the experiment. The reaction to the introduction of the preparation «Tsiflur» was estimated at 1 point, for each identified symptom.

Effect of Circulation Flowrate on the Performance of a Spiral Finned Freeze Concentrator

Progressive freeze concentration (PFC) has emerged as a viable technology for concentration of liquid solution. In this study, a newly designed spiral finned crystallizer to improve productivity of PFC process was proposed. The spiral fin is presented based on the advantage of additional surface area to the spiral finned crystallizer. The performance of spiral finned crystallizer was analysed by the system efficiency and the effect of circulation flowrate. It was found that the efficiency of the system has significantly improved in terms of a lower effective partition constant and a higher recovered solute. An effective partition constant of 0.35 and a recovered solute of approximately 0.96 g of glucose per 1 g of initial glucose were obtained. Thus, spiral finned crystallizer for PFC system is evidently an effective system to concentrate solution and to produce pure ice crystal.

ELUTION BEHAVIOR OF PHOSPHATE CONTAINED IN Mg/Fe AND Zn/Fe LAYERED DOUBLE HYDROXIDES

Layered double hydroxide (LDH) is a layered hydroxide and exchangeable anion is intercalated in its interlayer. Application of the LDH as a controlled-release material of interlayer anions has become of interest, thus it is important to clarify the elution behavior of interlayer anions. We synthesized hydrogenphosphate-intercalated Mg / Fe and Zn / Fe LDH and elution of phosphate from these LDH were tested in deionized water, sodium chloride solution, sodium sulfate solution, and sodium carbonate solution. For Mg / Fe LDH, the amount of eluted phosphate increased with time and reached to maximum that increased as higher concentrate solution was used. The elution of phosphate from Mg / Fe LDH could be described by the pseudo second-order equation. This elution behavior was explained as ion-exchange reaction of phosphate with sulfate or carbonate in tested solution by means of kinetic simulation using Runge-Kutta method. In the eluted solution, metal ions contained in the LDH were detected and its amount depended on pH of the tested solution, that is, amounts of eluted Mg and Zn ions were small at higher pH (ca. 10) for Mg / Fe and Zn / Fe LDH respectively, but large amount of Zn ion was detected when 2.03 mol·l-1 carbonate solution (pH = 13) was used. Thus elution of phosphate was caused by two main reactions: ion exchange and decomposition of the LDH.

Threshold scaling limits of RO concentrates flowing in a long waste disposal pipeline

Disposal of RO concentrates emanating from inland brackish water desalination plants presents a difficult environmental problem. The solution adopted by Mekorot - the National Water Company of Israel - is to construct a 30 km waste disposal pipeline for collecting concentrates emanating from several RO desalination plants and discharging them into the sea. The discharged concentrates are highly supersaturated with respect to CaCO3. Scale precipitation during concentrate flow through the RO module is inhibited by the presence of anti-scalants. The retention time of the concentrate solution in the discharge pipe will exceed 100 hours. This raises the issue of the risk of scale precipitation in the discharge pipe that could impair its proper functioning. The aim of the present study was to provide data for guiding the design and operation of the disposal pipeline. The extent of the induction period prior to the onset of precipitation was measured in a pilot plant simulating flow of concentrate solutions dosed with anti-scalants. The parameters investigated were the scaling potential, the anti-scalant concentration and the presence of a mixture of several anti-scalants. The results of this study provide threshold scaling limits under various conditions.