Process of Dissolution of Polydisperse Materials in a Unit with a Rotary Pulsation Apparatus

2015 ◽  
Vol 88 (1) ◽  
pp. 23-34 ◽  
Author(s):  
A. A. Kukhlenko ◽  
S. E. Orlov ◽  
D. B. Ivanova ◽  
M. S. Vasilishin
Author(s):  
O.Yu. Erenkov ◽  
◽  
I.Ya. Lopushanskiy ◽  
E.V. Yavorskaya ◽  
◽  
...  

2020 ◽  
pp. 103-110
Author(s):  
Larysa Sablii ◽  
Oleksandr Obodovych ◽  
Vitalii Sydorenko ◽  
Tamila Sheyko

This paper presents the results of studies of isolation lignin and hemicelluloses efficiency during the pre-treatment of wheat straw for hydrolysis in a rotary-pulsation apparatus. The pre-treatment of lignocellulosic raw materials for hydrolysis is a necessary step in the second-generation bioethanol production technology. The lignocellulose complex is destroyed during this process, and this allows hydrolytic enzymes access to the surface of cellulose fibers. The pre-treatment is the most energy-consuming stage in bioethanol production technology, since it usually occurs at high temperature and pressure for a significant time. One of the ways to improve the efficiency of this process is the use of energy-efficient equipment that allows intensifying heat and mass transfer. An example of such equipment is a rotary-pulsation apparatus, which are effective devices in stirring, homogenization, dispersion technologies, etc. The treatment of wheat straw in a rotary-pulsation apparatus was carried out under atmospheric pressure without external heat supply at solid/water ratios of 1:10 and 1:5 in the presence of alkali. It was determined that the treatment of the water dispersion of straw at ratio of 1:10 due to the energy dissipation during 70 minutes leads to the release of 42 % of lignin and 25.76 % of easily hydrolyzed polysaccharides. Changing the solid / water ratio from 1:10 to 1:5 leads to an increase in the yield of lignin and easily hydrolyzed polysaccharides to 58 and 33.38 %, respectively.


2019 ◽  
Vol 974 ◽  
pp. 195-200
Author(s):  
Yury R. Krivoborodov ◽  
Svetlana V. Samchenko

The article presents the results of a study of the effect of synthesized microdisperse additives of crystalline hydrates based on calcium sulfoaluminates on the properties of cement stone. The effectiveness of the use of a rotary pulsation apparatus (RPA) to obtain microdispersed additives is identified. The possibility of accelerating the hardening of cement stone by entering microdispersed additives into its composition is shown. It has been established that in the presence of microdispersed additives of crystalline hydrates in the cement stone, the phase composition of hydrate tumors changes, the amount of calcium hydrosilicates and ettringite increases, the porosity decreases and the strength of the cement stone increases. This provision is confirmed by the increase in the degree of cement hydration, the amount of bound water in all periods of hardening of the stone. It is proposed to use microdisperse additives, which play the role of primers for the crystallization of ettringite and calcium hydrosilicates, to increase the strength of cement stone in the early stages of hardening.


2015 ◽  
Vol 3 ◽  
pp. 22-25
Author(s):  
Gurinovich L.S. ◽  
Usov B.A.

The article is devoted to the obtaining of activated additives and cements, to improve the quality or the obtaining of new building materials using rotary pulsation apparatus (RPA). It also considers the efficiency of the RPA. As a result the works were obtained in different activated in the RPA chemical additives for concrete from sparingly soluble in water products established distinctive features of the solutions of plasticizers and complex additives, treated in the RPA. It is shown that the preparation of concrete with the use of activated materials in the RPA to reduce labor costs in the manufacture of a product, reduce the consumption of cement, flow additives, plasticizers, water consumption, accelerate hardening and to increase strength and durability of concrete. It is noted that when changing the amount of additives in the solution and time of mechanochemical treatment, it becomes possible to control the technological parameters of concrete mixture (mobility, stiffness) and thus increase the strength of concrete. When the content of additives PDO 0.15% and activation time of 5 minutes the increase in strength was 60 kg/cm2. With increasing number of activated additives up to 1 % strength in concrete was increased, while the introduction of the same amount of additives without activation promoted a decrease in strength below without additional values.


Technobius ◽  
2021 ◽  
Vol 1 (4) ◽  
pp. 0010
Author(s):  
Yerlan Sabitov ◽  
Duman Dyussembinov ◽  
Daniyar Bazarbayev

The given article is devoted to research of influence of polymer modifiers and mineral additives on quality of composite aerated concrete products. When selecting the composition of composite aerated concrete local raw materials and components were used: portland cement, sand, aluminum powder, polyvinyl acetate, fly ash, post-alcoholic bard and whey of milk. Preliminary polyvinyl acetate was combined with binder mixing water at a temperature above 55ºC to obtain a readily soluble polymer emulsion. Dispersion was carried out with a rotary-pulsation apparatus at a pressure of 0.5-1.0 MPa and a rotor speed of ~1200 rpm. In the same apparatus the complex modifier was produced. The offered technology of production of a complex modifier seems to be the most effective for composite aerated concrete. It made it possible to reduce water absorption and capillary suction of composite aerated concrete by an average of 25% and 45%, respectively. Moreover, different combinations of fly ash, polymer and modifier made it possible to achieve optimal values of thermal conductivity, compressive strength and frost resistance of composite aerated concrete.


1976 ◽  
Vol 10 (4) ◽  
pp. 536-538 ◽  
Author(s):  
V. A. Lygoreva ◽  
V. F. Gobert ◽  
M. A. Balabudkin ◽  
G. N. Borisov ◽  
N. M. Ezerskii

2019 ◽  
Vol 54 (11-12) ◽  
pp. 890-893
Author(s):  
O. Yu. Erenkov ◽  
I. Ya. Lopushanskii ◽  
E. V. Yavorskaya

Author(s):  
D.M. Borodulin ◽  
V.N. Ivanets ◽  
E.A. Safonova ◽  
M.V. Prosin ◽  
I.O. Milenkiy ◽  
...  

2020 ◽  
pp. 255-261
Author(s):  
Tat'yana Petrovna Shcherbakova

The possibility of complex processing of silica-containing plant biomass with the selection of a line of target products is investigated. The method includes the mechanochemical treatment of biomass in a solution of sodium hydroxide in a rotary pulsation apparatus at a temperature of self-heating not lower than 80 °C. The resulting suspension is separated on a solid residue and an extract. The solid residue is washed and dried to obtain pulp powder. The bio-filled silica gel with an SiO2 content of 49.4 wt.% to 62.6 wt.% is isolated from the extract after separation of the solid residue. By ashing the silicon-containing product at a temperature of 600 °C, amorphous silica is obtained. The content of SiO2 (as the target component) in the ash is 85.5–92.0%. The SiO2 diffraction pattern is characterized by the presence of a diffuse halo with a maximum at 2q=22.75 ° and the absence of diffraction peaks. Preliminary acid leaching can increase the purity of the resulting silica to 99.0%. The specific surface area of the obtained silica was determined by the BET method for nitrogen sorption at 260 m2/g. The effect of the concentration of the extractant on the yield of alkali-soluble substances and the degree of leaching of silicon was studied. It was shown that even at a 1% concentration of the extractant (NaOH), almost complete leaching of silicon from the plant matrix occurs. Depending on the increase in the concentration of NaOH, the degree of delignification of the biomass increases to 13–18–22%, respectively, with an increase in the concentration of NaOH 1–5–10%. Powdered cellulose was obtained with a content (%): silicon – 1.12, lignin – 34.8, alpha cellulose – 86.0, with a yield of 33.0% and a particle distribution of 80–300 μm. The amount of biomass loss is 17.6 wt.%.


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