Analysis of the Effect of Dry Magnetic Separation on the Process of Ferruginous Quartzites Disintegration

The paper considers the results of the application of dry magnetic separation on samples of ferruginous quartzites of the Kostomuksha ore field, represented by refractory ore, free-milling ore, and their mixture. The assessment of the influence of the ore texture on the technological parameters of dry magnetic separation indicates their insignificant changes: the yield of the non-magnetic product varies from 12.4 to 13.5%, and the Fetotal content in the magnetic product increases by 1.11–1.14 times. A decrease of at least 15% in the number of harmful impurities was found: S by 16.2–17.3%, SiO2 by 15.5–21.1%, and Al2O3 by 39.1–48.4%. The authors have performed a comparative assessment of the granularity of the initial ore and the magnetic product with the measurement of energy consumption, as well as an analysis of the magnetite liberation on particle sizes of less than 2 mm. It was found that due to the release of a non-magnetic product in the amount of 12.3–14.5%, represented by non-magnetite or weakly mineralized rock varieties, energy consumption for the crushing process is reduced by at least 5%. The mineral liberation assessment showed that mainly free magnetite is contained in the −0.4 mm fineness class. It was found that in the magnetic separation product of the refractory ore sample, the amount of liberated magnetite in the size class −1 + 0 mm increases by 12.1% compared to the initial ore sample. For the free-milling ore sample, the opposite trend is observed: a decrease in the amount of free magnetite by 30.9% in the magnetic product. Analysis of the magnetite liberation in the mixture indicates deterioration in the results obtained during the separate crushing of refractory and free-milling ore and a decrease in the amount of liberated magnetite in the magnetic product by 60% compared to the initial ore.

Growth of Au nanoparticles on phosphorylated zein protein particles for use as biomimetic catalysts for cascade reactions at the oil–water interface

A robust chemo- and biocatalytic cascade PIC with a recovery catalyst and a separation product was developed. The results groundbreakingly highlighted the preliminary applications of artificial enzymes and bio-enzymes in a one-pot cascade PIC.

Recovery of Cenospheres and Fine Fraction from Coal Fly Ash by a Novel Dry Separation Method

Aluminosilicate microspheres are a valuable fraction of coal fly ash with diverse applications due to their low density. Currently, there is no efficient and ecologically rational method of cenosphere recovery from fly ash. A combination of dry methods for the recovery of both fine ash particles and aluminosilicate microspheres from coal fly ash is presented. It is comprised of fluidised bed separation followed by screening and pneumatic separation in a free-fall air chamber. Fluidised bed separation was assisted by a mechanical activator to prevent agglomeration. This step reduced the portion of material that required further treatment by 52–55 wt.%, with the recovery of microspheres exceeding 97%. Then, the concentrates were individually subjected to pneumatic separation. The final separation product for the fly ash containing 0.64 wt.% cenospheres was a cenosphere concentrate that constituted about 17 wt.% of the initial fly ash. The recovery of cenospheres was around 81%. Usage of a combination of dry methods allowed for maintaining almost 83 wt.% of the raw material in its dry form. Furthermore, the produced fly ash grain fractions could be used for different industrial purposes.

The Influence of Selected Properties of Particles in the Jigging Process of Aggregates on an Example of Chalcedonite

The influence of the physical, geometric and chemical properties of particles on the results of aggregate separation by means of a laboratory ring jig is presented in this paper. The experiment was based on separation of chalcedonite particles in a narrow particle size fraction composed separately of regular and irregular particles, which was prepared in accordance with patent inventions. On its basis, the geometric properties—projection diameter and (volumetric and dynamic) shape coefficients—as well as physical properties—particle density—were determined in products of the regular and irregular particles. The terminal settling velocities of the regular and irregular particles were calculated for a randomly selected sample of particles in each obtained separation product. The statistical analysis of the geometric properties of the particles allowed to evaluate the influence of these parameters on aggregate processing with respect to selection of particles homogenous in terms of their shapes. The comparison of the particle shapes’ influence on the chalcedonite feed separation effects was made by the means of the values of the shape coefficients: the dynamic and volumetric ones. Additionally, tests were carried out using Raman spectroscopy in order to determine the mechanisms of density change in the aggregate. The research goal was realised through detecting and analysing the polymorphic forms of the silica and allogenic minerals precipitated on the surface and inside the chalcedonite particles.

ACETONE-CHLOROFORM-n-BUTANOL MIXTURE SEPARATION BY THE EXTRACTIVE DISTILLATION IN SCHEMES OF TWO-OUTLET COLUMNS

Extractive distillation of acetone-chloroform-n-butanol mixture with dimethylformamide in two-outlet column schemes is considered. Optimal parameters according to the total energy consumption criterion in the column boilers of the three extractive distillation schemes for this mixture separation are determined. Calculations were carried out in a design-verification version at 1000 kg/hr of the initial mixture with the concentrations of acetone, chloroform and n-butanol 71.3, 14.7 and 14.0% wt., respectively. Dimethylformamide concentration in the entrainer flow was set to 99.99 wt%. The main component concentration in the product stream was 99.9 wt% for chloroform and 99.5 wt%. for acetone and n-butanol. The parameters to be optimized were: the number of plates in the columns, the temperature and flow rate of dimethylformamide, reflux ratios, distillate flow rates and the position of the feed plates in the columns. The optimum location of the entrainer feed plate was found additionally in the extractive distillation column. Separation product concentrations served as the constraints of the optimization. The optimization was carried out in Aspen Plus with the use of a combination of Sensitivity Analysis and sequential quadratic programming (SQP). It is established that scheme P5 has the lowest energy consumption. In the first column of this scheme, n-butanol is separated, and then the azeotrope-forming components (acetone and chloroform) are separated by the extractive distillation subsystem. Energy consumptions for two other schemes (P1 and P2), in which dimethylformamide is used in the first column of the sequence, are significantly higher than for scheme P5 - by 69.1% and by 49.3%, respectively. The data obtained will be used: to synthesize and optimize the extractive distillation schemes including the subsystems with coupled thermal and material flows to separate the acetone-chloroform-n-butanol mixture; to estimate the energy efficiency of those schemes and to obtain the criterion for estimating the energy efficiency of systems with coupled thermal and material flows in the extractive distillation of multicomponent mixtures.

Study on Changes of Nitrobenzene Degrading Bacteria in ABR Reactor

By adding nitrobenzene to ABR (anaerobic baffled reactor) acclimation the flora in it, take 5 chambers sludge, extracted DNA and using PCR-DGGE technique amplification and separation product of bacterial 16S rDNA gene V3 region, then study the changes and diversity anaerobic sludge bacteria. The results showed that there was a succession in the communities of 5 reactor compartment, and the microbial diversity changes showing a characteristic of synergistic. ABR reactor has obvious characteristics of multi-phase process.

METODE PEMBELAJARAN BAHAN MAGNET DAN IDENTIFIKASI KANDUNGAN SENYAWA PASIR ALAM MENGGUNAKAN PRINSIP DASAR FISIKA

A Method in Learning Magnetic Substance Characteristics and Identifying Natural Sand Compound Contents Through Basic Principles in Physics. This study was conducted by separating ferrate sand from natural sand in an area in Indramayu Regency in the form of the titanomagnetite Fe2.5Ti0.5O4 compound by means of a magnetic separator with a power of 0.3 tesla. Using this method, the titanomagnetite content of the natural sand was capable of being improved from 32% to 63.6% (for sand in River Cimanuk’s tributary) based on the analysis using XRD (X-Ray Difractometer) using the GSAS (General Structure Analisis System) program with a Chi2 of 1.454 and Wrp as a correction factor for the difference in the intensity of the two patterns was 0.1142 (11.42%). The value of Chi2 which was almost 1 dan and that of Wrp which was almost 10% showed that the data were acceptable (with a probability of ~0.1). To enhance the titanomagnetite content of the separation product, an extraction-solving process was conducted using HCl 32% and NH4OH 25%. The results of the analysis using XRF (X-Ray Flourosence) showed that the content which was most probably a titanomagnetite compound increased its weight fraction to almost 100%. Keywords: ferrate sand, titanomagnetite, permanent magnet