scholarly journals Continuous production of multicomponent powder mixtures

2020 ◽  
Vol 315 ◽  
pp. 04003
Author(s):  
Wasem Mansour ◽  
Denis Melekhin ◽  
Alexander Pasko

Mixing of powders is an important process in various industries, from chemical, pharmaceutical to food and construction. The main characteristic of the mixture is its homogeneity, which is usually estimated by the coefficient variation and the lower this ratio, the better the mixture. Typically, particles of the components of the mixture differ in size and / or density. These differences cause segregation, i.e. the formation of zones in which there is a high concentration of one of the components and this affects the quality of the mixture. However, through the use of special technological methods, the negative result of segregation can be transformed into a positive one and not only reduce the mixing time, but also improve the quality of the mixture. This article discusses one of the options for the production of a multicomponent mixture with a specific schedule for loading components. It is shown that by organizing the correct sequence of loading components, you can control the mixing process. Two-step technology is used to feed components into the mixer.

2015 ◽  
Vol 92 (5) ◽  
pp. 427-433 ◽  
Author(s):  
Rui Liu ◽  
Yimin Wei ◽  
Xiaolong Ren ◽  
Yanan Xing ◽  
Yingquan Zhang ◽  
...  

2014 ◽  
Vol 693 ◽  
pp. 261-266 ◽  
Author(s):  
Jolanta B. Krolczyk ◽  
Marek Tukiendorf ◽  
Rafał Dawid

The paper presents the research on the quality of thirteen-component granular mixture. The changes in the quality of the mixture after reduction the mixing time from a standard time of 30 minutes to: 25 minutes, 20 minutes and 15 minutes have been analyzed. The research has been conducted in industrial conditions where a vertical mixer with worm agitator with the charge of two tons was used. Research results were presented graphically as changes in concentration of components shares in the mixing time of 30, 25, 20 and 15 minutes and the obtained results were compared. Quality assessment of a thirteen-component mixture with the use of residual sum of squares for four mixing times was carried out.


1972 ◽  
Vol 11 (2) ◽  
pp. 153-155 ◽  
Author(s):  
N. A. Nesterenko ◽  
V. A. Chizh ◽  
G. F. Degtev ◽  
S. A. Faityants ◽  
L. I. Pugina

Pharmaceutics ◽  
2021 ◽  
Vol 13 (4) ◽  
pp. 563
Author(s):  
Bruna Marianni ◽  
Hudson Polonini ◽  
Marcone A.L. Oliveira

The mixing process plays a pivotal role in the quality of pharmaceuticals and food/dietary supplements, as it can impact the homogeneity of the substances in their dosage form and affect characteristics such as dissolution and stability. Thus, the choice of the right mixing device is paramount for compounding pharmacies. In this paper, we evaluated the mixing efficacy of a new 3-axis mixer device and determined its optimal working conditions. Three different formulations were compounded with the device and a total of 540 individual assays were performed by HPLC or ICP-MS to validate its use, in addition to a direct comparison among it and two alternative mixing methods. The 3-axis mixer device was able to provide homogeneous mixtures and finished capsules with adequate content uniformity with a broad range of conditions of use (mixing times from 2 to 8 min, and speed of rotation from 10 to 100 rpm). In addition, the device was superior to classical mixing methods (such as the use of manually shaken plastic bags) and at least equivalent to well-established ones (Y-shaped mixer). Finally, we proposed a cleaning procedure that was also adequate to prevent cross-contamination among products compounded with the same device.


2019 ◽  
Vol 252 ◽  
pp. 04004
Author(s):  
Mathias Romańczyk ◽  
Witold Elsner

This study was devoted to improving the mixing quality in a Venturi gas mixer. It is well known that the performance of industrial gas engines strongly depends on the quality of air and fuel mixture and therefore on its homogeneity. Incorrect mixture proportions may lead to unstable operation of the entire industrial gas engine and excessive emissions exceeding environmental standards of the European Union. The effectiveness of the mixing process in a Venturi gas mixer depends on many factors, i.e. correct proportions between Air inlet, Venturi Throat diameter, as well as gas inlet area. To improve the intensification of the whole mixing process, as well as to increase the mixing time between gas and air, it was decided to insert disturbing elements in form of cylindrical turbulators into the Venturi pipe. Therefore numerical calculations were performed for the most commonly consumed by industrial gas engines lean Air-Fuel mixture, with an air excess coefficient ratio of λ = 1.6. In numerical analysis, OpenFOAM software was used to investigate the impact of cylindrical turbulators on the whole mixing process in a basic Venturi gas mixer. Particular attention was focused on the Air-Fuel Ratio (AFR) changes, Turbulent Kinetic Energy (TKE) and Pressure loss [Pa], which is one of the most qualitative evaluation parameters of a gas mixer.


2017 ◽  
Vol 35 (No. 6) ◽  
pp. 522-531 ◽  
Author(s):  
Sluková Marcela ◽  
Levková Julie ◽  
Michalcová Alena ◽  
Horáčková Šárka ◽  
Skřivan Pavel

The changes in the structure of cereal proteins during the mixing of flour into dough was described and evaluated. Wheat gliadins and glutenins (gluten proteins) have unique physical properties and play an important role in breadmaking. The effect of mixing time on the formation and the structure of the gluten network was determined using scanning electron microscopy (SEM). Buckwheat flour (gluten-free) was used to compare the development of structure during the mixing process.


2019 ◽  
Author(s):  
Chem Int

The assessment of groundwater is essential for the estimation of suitability of water for safe use. An attempt has been made to study the groundwater of selected areas of Punjab (Sheikhupura & Sahiwal) and Sindh (Sindh, Jawar Dharki and Dharki), Pakistan. The results indicate that pH, color and odor were all within limits of WHO that is pH ranges 6.5–8.5, colorless and odorless, respectively. The high values of suspended solids were observed in the Sindh-1 and Dharki samples. Microbiologically only Sahiwal and Jawar Dharki were found fit for drinking purpose. Trace metals analysis of Sheikhupura-1 and Sindh-1 showed that values do not fall within limits of WHO for Iron. The ionic concentration analysis showed that high bicarbonate (HCO3-), ions are present in the samples of Sahiwal and Dharki; Sindh-1 and Jawar Dharki samples showed very high concentration for chloride ions, all samples were satisfactory level for sulphate (SO42-), sodium, magnesium and phosphate ions except samples of Sindh-1 and Jawar Dharki. High concentration of calcium and potassium ions was observed in samples of Sindh-1, while all other samples were found fit for drinking purposes in respect of nitrate, nitrite and ammonium ions. The high concentration of Fluoride was found only in Sheikhupura-2 samples.


Author(s):  
М.А. ХАШАГУЛЬГОВА ◽  
У.А. ХАШАГУЛЬГОВ ◽  
О.О. ГЕТОКОВ

Изучено влияние технологических приемов на качество муки. Определяли качество зерна озимой мягкой пшеницы Краснодарская 57 по ГОСТ 93532016. При определенной технологической схеме 78м двухсортном выходе муки было получено 70 муки 1го сорта и 8 муки 2го сорта. Качество муки соответствует ГОСТ Р 521892003. Мука 1го и 2го сортов обладает пресным вкусом, запахом, свойственным пшеничной муке массовая доля влаги 14,7 (1й сорт) и 13,5 (2й сорт). Наличие минеральной примеси, зараженность вредителями не установлены. Содержание металломагнитной примеси 0,041 мг (1й сорт) и 0,048 мг (2й сорт), что соответствует стандарту. Массовая доля золы в пересчете на сухое вещество составила не более 0,69 для муки 1го сорта и 0,70 для муки 2го сорта, белизна у. е. прибора РЗБПЛ 52,4 (1й сорт) и 30,0 (2й сорт). Качество сырой клейковины для муки 1го и 2го сортов составляет 70,0 и 78,0 у. е. прибора ИДК1 (I группа) соответственно. Определены также крупность помола остаток на сите 2,0 1,9 и 2,2, число падения 200 и 182 с, массовая доля сырой клейковины 30,3 и 26,6, содержание протеина 13,2 и 12,5 для муки 1го и 2го сорта соответственно. Цвет белый для муки 1го сорта и белый с желтоватым оттенком для муки 2го сорта. По органолептическим и физикохимическим показателям пшеничные отруби соответствовали ГОСТ 716966. В результате гидротермической обработки зерна с применением холодного кондиционирования и отволаживанием в течение 4 ч выход сырой клейковины вследствие повышения водопоглотительной способности белков увеличился с 25 до 26,6. Одновременно наблюдалось ослабление клейковины, возрастание ее растяжимости. При отволаживании зерна в течение 6 и 8 ч происходило некоторое увеличение выхода сырой клейковины, : 27,9 и 30,3 соответственно. Качество клейковины составило 70 у. е. прибора ИДК1, что соответствует I группе качества. Выход муки при 4часовом отволаживании составил 64, при 6часовом увеличился до 66. Высокий показатель общего выхода муки 78 был установлен при 8часовом отволаживании. Холодное кондиционирование способствовало улучшению мукомольных и хлебопекарных свойств зерна, увеличению выхода сортовой муки при меньших затратах электроэнергии. The influence of technological methods on the quality of flour has been studied. The quality of winter wheat Krasnodarskaya 57 was determined according to GOST 93532016. At a certain technological scheme with a seventyeight percent twograde flour yield was obtained 70 flour 1st grade and 8 flour 2nd grade. The quality of flour corresponds to GOST R 521892003. Flour of the first and second grades has a fresh taste, the smell characteristic of wheat flour, the mass fraction of moisture 14,7 (1st grade) and 13,5 (2nd grade). The presence of mineral impurities, pest contamination has not been established. The content of metallomagnetic impurities was found to be 0,041 mg (1st grade) and 0,048 mg (2nd grade), which corresponds to the standard. Mass fraction of ash in terms of dry matter was no more than 0,69 for first grade flour and 0,70 for flour of the second grade, whiteness conditional units of the device RZBPL 52,4 (1st grade) and 30,0 (2nd grade). The quality of wet gluten for flour of 1st and 2nd grades is 70,0 and 78,0 units of the device IDK1 (I group) respectively. Were also defined the particle size of grinding the residue on the sieve 2,0 1,9 and 2,2, the falling number 200 and 182 seconds, the mass fraction of wet gluten 30,3 and 26,6, protein content 13,2 and 12,5 for flour 1st and 2nd grade, respectively. The color is white for the flour 1st grade and the white with a yellowish tinge for the flour of the 2nd grade. By organoleptic and physicochemical indicators, wheat bran complied with GOST 716966. As a result of hydrothermal grain treatment with the use of cold conditioning and softening for 4 hours, the yield of raw gluten due to an increase in the waterabsorbing ability of proteins increased from 25 to 26,6. At the same time, a weakening of the gluten was observed, an increase in its extensibility. When softening grain for 6 and 8 hours there is some increase in the yield of wet gluten, : of 27,9 and 30,3 respectively. The quality of gluten was 70 units of the device IDK1, which corresponds to the quality group I. The yield of flour with fourhour softening was 64, with sixhour increased to 66. High total yield of flour of 78 was set when the eighthour softening. Cold conditioning contributed to the improvement of the milling and baking properties of grain, increasing the yield of highgrade flour with less power consumption.


Author(s):  
Evgeny Kharin ◽  
Olga Belykh

In the context of the development of infrastructure in Siberian cities, the issues of the state of the areas with accumulated environmental damage is especially relevant. It is mentioned in the article that lichen indication is an efficient method of passive monitoring of environment for industrial pollutants caused by morphological changes occurring in sensitive objects. The results of the lichen floristic research of Leninsky district of Irkutsk are presented, a list of revealed lichens including 9 genera and 12 species is given, a taxonomic list of this area is discussed. Lichenological objects were mapped. Distribution of lichens in the area of research is investigated with regard to the presence of recreational and residential zones. The authors draw a conclusion about the presence of «lichens deserts» which are caused both by the absence of the respective substratum and high concentration of pollutants. High concentration of pollutants is caused by complex influence of different enterprises on the quality of air.


2021 ◽  
Vol 18 (1) ◽  
Author(s):  
Adèle Bourmaud ◽  
Georges Dahm ◽  
François Meys ◽  
Nicolas Gengler ◽  
Alain Origer ◽  
...  

Abstract Background Heroin and cocaine are among the most dangerous illicit drugs available and their presence on the market is increasing. These facts have led to the investigation of the quality of heroin and cocaine samples seized in Luxembourg by police and customs but also collected at the national supervised drug consumption facilities. Methods Samples obtained from 2019 to 2020 were analyzed to determine their composition and content using GC–MS, HPLC-UV and LC-Q-ToF. The statistical evaluation of concentration changes depending on the source of collection is based on an ANOVA single factor test and a two-tailed t test. Results Results showed important differences between seizure and collection sources. For both drugs, customs samples had significantly higher concentrations than police samples and the latter had significantly higher concentrations than samples from drug consumption facilities, whereas for heroin two cutting steps were identified, for cocaine samples only one appears to occur on the local market. Indeed, cocaine samples seized by police consisted of a mixture of low and high concentration samples. Conclusion The results show that extensive adulteration with pharmacological active and inactive compounds takes place at local levels, which, however, are different for heroin and cocaine. This knowledge on variability of quality of drugs should be considered in the elaboration of drug and harm prevention strategies.


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