Cavitation Treatment Research Articles

Modification of motor gasoline with bioethanol in the cavitation field

The article presents the results of the study on the influence of bioethanol content and parameters of cavitation field on the octane number of motor natural gasoline. The effects of the parameters of cavitation field on the modification of fuel and the changes of qualitative and quantitative composition of gasoline were investigated. The influence of the content of a biocomponent on the increase in the octane number was established. It was stated that the problem of the phase separation in alcohol-gasoline mixture can be solved by means of dynamic cavitation. The paper presents the results of the study of the change of octane number as a function of the intensity of cavitation treatment for gas condensate gasoline with addition of bioethanol. The physical stability of gas condensate and bioethanol mixture after cavitation treatment is investigated. It was shown that the gas condensate gasoline modified with bioethanol and cavitation field can be used as a high-quality motor gasoline. It was stated that low-octane gas condensate gasoline can be transformed into high-quality motor fuel by means of modification with bioethanol in the cavitation field. It was established that the alcohol-gasoline cavitation treatment leads to the homogenization and provides at least 30 days' mixture stability before separation. With increasing bioethanol content in the mixture, the number of cavitation cycles (intensity) required to achieve a constant octane number value decreases from 8 cycles for gas condensate gasoline without bioethanol to 4 cycles at the content of bioethanol of 3% and above.

The Alternative Method of Conditioning Industrial Wastewater Containing Heavy Metals Based on the Hydrothermodynamic Cavitation Technology

This article provides the results of studies of modifying the physicochemical properties of industrial wastewater when treated in a cavitation reactor. The authors performed an analysis of physicochemical changes in the makeup of industrial effluent and defined the efficiency of reducing the content of heavy metal ions under various modes of hydrothermodynamic action. The article also proposes the methods of mathematical modelling for determining the optimal parameters of cavitation treatment of wastewater and reveals the advantages of upgrading the wastewater process equipment with the inclusion of a unit of SC-reactors

The Alternative Method of Conditioning Industrial Wastewater Containing Heavy Metals Based On The Hydrothermodynamic Cavitation Technology

This article provides the results of studies of modifying the physicochemical properties of industrial wastewater when treated in a cavitation reactor. The authors performed an analysis of physicochemical changes in the makeup of industrial effluent and defined the efficiency of reducing the content of heavy metal ions under various modes of hydrothermodynamic action. The article also proposes the methods of mathematical modelling for determining the optimal parameters of cavitation treatment of wastewater and reveals the advantages of upgrading the wastewater process equipment with the inclusion of a unit of SC-reactors.

Production of biologically active peptides by hydrolysis of whey protein isolates using hydrodynamic cavitation

Whey protein isolate (WPI) hydrolysates have higher solubility in aqueous phase and enhanced biological properties. Hydrolysis of WPI was optimized using operating pressure (ΔP, bar), number of passes (N), and WPI concentration (C, %) as deciding parameters in hydrodynamic cavitation treatment. The optimum conditions for generation of WPI hydrolysate with full factorial design were 8 bar, 28 passes, and 4.5% WPI concentration yielding 32.69 ± 1.22 mg/mL soluble proteins. WPI hydrolysate showed alterations in binding capacity over WPI. SDS-PAGE and particle size analysis confirmed the hydrolysis of WPI. Spectroscopic, thermal and crystallinity analyses showed typical properties of proteins with slight variations after hydrodynamic cavitation treatment. ABTS, DPPH and FRAP assays of WPI hydrolysate showed 7–66, 9–149, and 0.038–0.272 µmol/mL GAE at 1–10, 0.25–4, and 3–30 mg/mL concentration, respectively. Further, a considerable enhancement in fresh weight, chlorophyll, carotenoids, reducing sugars, total soluble sugars, soluble proteins content and total phenolics content was noticed during in vitro growth of sugarcane in WPI hydrolysate supplemented medium at 50–200 mg/L concentration over the control. The process cost (INR/kg) to hydrolyze WPI was also calculated.

Effect of cavitation treatment of coal-water and composite liquid fuels on their characteristics

The effect of mechano-cavitation treatment of coal-water and artificial composite liquid fuels, based on brown coals and anthracite, on particle size distribution of their coal mass and dynamic viscosity is studied experimentally. It is shown that the treatment of both fuels leads to significant regrinding of their coal mass and a noticeable increase in viscosity.

Surface Characteristics and Cavitation Damage in 8090Al–Li Alloy by Using Cavitation Water Jet Peening Processing

The cavitation strengthening test of Aluminum lithium Alloy (8090Al–Li) was carried out with different pressure process parameters. The roughness, residual stress, and morphology of the treated samples were studied. A high dislocation density was formed in the cavitation area of the workpiece, which resulted in surfacing hardening. The cavitation effect occurred in the collapse area. It was beneficial for the process to be the right choice for the surface treatment of metal materials. The results confirmed that surface roughness, grain size, micro-strain, erosive effect, and micro-hardness of the alloy were significantly affected by different cavitation peening pressures. In this case, surface roughness increased as the impact pressure increased. Besides, the microcrystalline structure decreased in the cavitation treatment area. The study showed on how the impact of the different cavitation peening pressure could suppress the material surfaces, the compressive residual stress, attained the maximum values of −137 MPa to −162 MPa, which increased from 7.87 to 27.56%, as compared to the original sample. In contrast, the corresponding surface roughness average increased to 3.04 μm. Experimental observation shows that the cavitation collapse boundaries obtained by the proposed sample surface and metallographic images were highly complete and accurate.

Acoustic and hydrodynamic cavitation assisted hydrolysis and valorisation of waste human hair for the enrichment of amino acids

Hair waste in large amount is produced in India from temples and saloons, India alone exported approximately 1 million kg of hair in 2010. Incineration and degradation of waste human hair leads to environmental concerns. The hydrothermal process is a conventional method for the production of hair hydrolysate. The hydrothermal process is carried out at a very high temperature and pressure, which causes the degradation of heat-sensitive essential amino acids, thereby depleting the nutritional value. This work deals with alkaline hydrolysis of human hair using acoustic and hydrodynamic cavitation, and comparison with the conventional method. The optimal operating conditions for highest efficiency was observed, for the hydrolysis of 1 g of sample hairs in 100 mL of solution, at 4:1 (KOH: hair) ratio, soaking time of 24 h, the ultrasonic power density of 600 W dm−3 (20 KHz frequency and input power 200 W) or hydrodynamic cavitation inlet pressure of 4 or 7 bars. Cavitation results in rupture of disulfide linkages in proteins and mechanical effects lead to cleavage of several hydrogen bonds breaking the keratin sheet structure in hair. Breakdown of bonds leads to a decrease in viscosity of the solution. 10% and 6% reduction in viscosity is obtained at optimal conditions for ultrasonic and hydrodynamic cavitation treatment, respectively. FTIR analysis of produced hair hydrolysate confirmed that the disulfide bonds in hair proteins are broken down during cavitation. The amino acid of hair hydrolysate, prepared using cavitation, has a relatively higher digestibility and nutritional value due to the enhancement of amino-acid content, confirmed using amino acid analysis. Cavitation assisted hair hydrolysate has a potential application in agricultural engineering as a fertilizer for improvement of the quality of the soil and land. Cavitation based hair hydrolysate can also be used as an environmentally friendly and economical source of essential amino acids and digestibles for animal or poultry feed.

Cavitation action on the cocci bacteria

Features of growth of microorganisms on a nutrient medium and their microscopic researches were studied. Cavitation treatment (22 kHz, 91 W, 1.65 W/сm3) of water with the simultaneous action of bubbled inert gases (argon and helium) on the viability of microbial cells (Diplococcus and Sarcina) are presented. The highest water disinfection was obtained for water samples with Sarcina lutea cells for both used gases under cavitation conditions. Both investigated types of cocci bacteria were destroyed faster under Ar/US-action after comparison of the effectiveness of the gas nature action on the water disinfection.

RESEARCH OF CHANGE IN FRACTION COMPOSITION OF VEHICLE GASOLINE IN THE MODIFICATION OF ITS BIODETHANOL IN THE CAVITATION FIELD

The influence of bioethanol content and parameters of the cavitation field on the quality indicators of motor gasolines: volatility and octane number is studied. Studying the effect of bioethanol and cavitation treatment of bioethanol-gasoline mixture will make it possible to produce automotive fuels for different climatic zones, or winter (summer) versions of gasolines. The use of bioethanol and cavitation treatment of a bioethanol-gasoline mixture affect the fractional composition of motor gasoline and its volatility. The optimal content of the biocomponent, at which there is an increase in the volatility of gasoline, is established Also the results of the octane number change are presented depending on the intensity of cavitation treatment for gas condensate with the addition of bioethanol. The influence of bioethanol content on the increase in octane number during cavitation treatment is determined. It is found that the introduction of bioethanol into the composition of gasoline leads to an improvement in its volatility. In this case, cavitation treatment makes it possible to obtain a mixture resistant to delamination. The addition of bioethanol leads to an adequate increase in light fractions during mechanical mixing and to a change in the fractional composition of the bioethanol-gasoline mixture during cavitation treatment. The addition of bioethanol in amounts up to 10% leads to a decrease in the saturated vapor pressure during cavitation treatment of bioethanol-gasoline mixtures, and an increase in the bioethanol content up to 20% leads to an increase in the saturated vapor pressure, which is explained by a change in the chemical composition of fuel components in comparison with the mechanical method of preparing mixtures. By cavitation treatment it is possible to change the fractional composition, the pressure of saturated vapors and the volatility of bioethanol-gasoline mixtures, making cavitation a promising energy-saving process for the production of gasoline for various climatic conditions

Image-Guided Treatment of Primary Liver Cancer in Mice Leads to Vascular Disruption and Increased Drug Penetration.

Despite advances in interventional procedures and chemotherapeutic drug development, hepatocellular carcinoma (HCC) is still the fourth leading cause of cancer-related deaths worldwide with a <30% 5-year survival rate. This poor prognosis can be attributed to the fact that HCC most commonly occurs in patients with pre-existing liver conditions, rendering many treatment options too aggressive. Patient survival rates could be improved by a more targeted approach. Ultrasound-induced cavitation can provide a means for overcoming traditional barriers defining drug uptake. The goal of this work was to evaluate preclinical efficacy of image-guided, cavitation-enabled drug delivery with a clinical ultrasound scanner. To this end, ultrasound conditions (unique from those used in imaging) were designed and implemented on a Philips EPIQ and S5-1 phased array probe to produced focused ultrasound for cavitation treatment. Sonovue® microbubbles which are clinically approved as an ultrasound contrast agent were used for both imaging and cavitation treatment. A genetically engineered mouse model was bred and used as a physiologically relevant preclinical analog to human HCC. It was observed that image-guided and targeted microbubble cavitation resulted in selective disruption of the tumor blood flow and enhanced doxorubicin uptake and penetration. Histology results indicate that no gross morphological damage occurred as a result of this process. The combination of these effects may be exploited to treat HCC and other challenging malignancies and could be implemented with currently available ultrasound scanners and reagents.

Investigation of sludge solubilization and phosphorous release in anaerobic side-stream reactor with a low pressure swirling jet hydrodynamic cavitation treatment

In this study, the feasibility of a novel hydrodynamic cavitation (HC) system was evaluated to speed up the biological sludge reduction mechanisms of the anaerobic side-stream reactor (ASSR) process. In the first part of the research, HC was performed on ASSR sludge by using a low pressure swirling jet cavitation system, named Ecowirl – EW 25. The effects of the Ecowirl – EW 25 system, in terms of sludge solubilisation, disintegration degree and microbial activity, were investigated considering two different injection plates, respectively, with two and four injection slots and four different treatment times, from 10 to 80 minutes. The best results were achieved after 80 min of HC treatment, using the plate with two injection slots and with a specific supplied energy (SE) equal to 12670 kJ kg TSS-1. Respirometric tests showed an increase in the readily biodegradable COD through the HC treatment of sludge. Moreover, low endogenous decay rates (bH) were measured on the ASSR sludge for SE lower than 6340 kJ kg TSS-1 revealing that the sludge solubilization was due to a modification in the floc structure rather than a decrease in the biomass viability. In the second part of the research, the solubilized sludge, after HC treatment, was used as carbon substrate for the biological activity of bacteria into the ASSR, such as total phosphate accumulating organisms (TPAOs). Results revealed that the phosphorous releasing and uptake rate, obtained using the HC treated sludge as carbon source, were comparable with those obtained with the addition of a ready biodegradable carbon source such as acetate.

Estimation of efficiency of ultrasonic cavitation processing of technological media on energy criteria

The paper presents the energy evaluation of cavitation treatment of technological environments with the aim of establishing such parameters that implement the optimal conditions to maximize the transfer of energy to the stages in cavitation generation, development and slam shut bubbles. Accounting multiple transformation of energy of ultrasonic vibrations, as the need to improve the efficiency of the process based on the gradual definition of qualitative and quantitative picture of the energy in the contact zone of cavitation and technological environment and conditions of transfer of energy to the technological environment. Definition and consistent calculation of the energy conversion chain for the implementation of this idea used existing and developed new criteria for evaluating methods of acoustic treatment of technological environments: the intensity, the ratio of energies, a synergistic coefficient, coefficient of energy absorption, the rate of change of pressure in time; the wave resistance of the medium in the regimes of cavitation resistance of the initial state of the environment and others. This approach, as the process of improving existing or establishing new systems and technologies is synergistic systems. On the basis of research and evaluation of these criteria formulated synergistic principles of perfecting of conditions and parameters of the system “ultrasonic installation – technology environment”.

Vibroresonant cavitator for homogenization of freshwater algae as raw materials for bioenergy

The technological process of processing blue-green algae of freshwater reservoirs into biogas has been improved. To increase the productivity of the biogas fermentation process, a new design of vibration-resonant cavitator was created. Productivity of the developed cavitator reaches 0,75–1,0 m3/h. with a cross section of the working chamber of 10 inches. The use of the cavitation treatment of algae suspension at the stage of preparation of the algae suspension allows to increase the fermentation of biogas from biomass by 25 ÷ 30 %. The aim of the work is to improve the technological process of fermentation of biogas from blue-green algae, as well as to develop a suitable design of the vibrocavitator. The main objectives of the study are to develop the design of vibrocavitators with electromagnetic drive and study the effectiveness of their use for homogenization of blue-green algae in the process of their processing into biogas.The results of the study allow to increase the productivity of the technology of algae processing into biogas, as well as to improve the ecological condition of water bodies and the environment by removing harmful blue-green algae from the water.

Dynamic behavior of acoustic cavitation bubble originated from heterogeneous nucleation

Acoustic cavitation bubbles are considered to be generated due to heterogeneous nucleation because a smaller amount of energy is required in this case compared with homogeneous nucleation. A typical example of such nucleation sites is tiny cracks filled with gas, commonly termed as “gas pocket.” Such microcracks can exist in abundance on the surface of reactor walls or sonotrodes used for the cavitation treatment. Eventually, the heterogeneously nucleated cavitation bubble is detached from the solid surface; however, the detachment mechanism has been unclear so far. Therefore, the present study numerically investigated the dynamic behavior of the cavitation bubble originated from the heterogeneous nucleation at wall cracks. During propagation of an ultrasound wave through a liquid, gas pockets in cracks oscillate sinusoidally when the sound pressure amplitude and crack radius are small. In this case, the bubble cannot detach from the surface. On the other hand, as the sound pressure amplitude, crack size, and/or contact angle become larger, the bubble begins to oscillate non-linearly that causes liquid jetting. The liquid jetting can cause the bubble detachment from the surface due to the interaction between the liquid jet and the bottom wall. Stronger liquid jetting makes many small detached bubbles.

EXPERIMENTAL STUDIES OF THE BAISHESHEK BARLEY GRAIN PROCESSED BY THE ION-OZONE MIXTURE

The article presents the results of an experimental study of Baisheshek barley grain treated with an ion ozone mixture. This study aims to develop an innovative technology for processing barley with an ion-ozone mixture in order to increase their technological parameters, yield, quality, and grain safety. Kazakhstan has sharply increased the export of barley, and all agronomists, producers, and breeders are actively moving to the cultivation of this crop, while increasing production, productivity, improving product quality, reducing their losses and ensuring storage safety are an urgent task. Microorganisms play an important role during storage, they fall into crop production in a variety of ways, and if they fall into unfavorable storage conditions after harvesting, crop production quickly deteriorates, harmful substances such as toxins, mold, and others accumulate in it, which reduces the commodity value. To solve these problems, experimental studies were conducted on barley of the Baisheshek cultivar treated with an ion-ozone mixture with and without using excess pressure (cavitation). The calculated full-factorial design of experiments of the 23 (8 experiments) and 24 (16 experiments) degrees made it possible to obtain regression equations describing the change in the seed, physico-biochemical, and physiological properties of barley of the Baisheshek variety. The solution of a comprehensive model for optimizing programming for different barley indices made it possible to establish optimal technological processing modes and achievable levels of technological qualities of grain. The effect of the proposed technology for ion-ozone and ion-ozone cavitation treatment is the ion-ozone mixture, which produces deodorization, disinfection of grain, following chemical-physical processes, increases biological value, accelerates the processes of grain metabolism. Studies conducted to improve germination, viability, and growth strength show a reasonably clear picture in terms of their ultimate value. Phenological observations showed that the effects of ion-ozone and ion-ozone cavitation treatment is triggered after 25-30 days. It was found that the greatest tendency for superiority is observed with ion-ozone cavitation treatment, followed by ion-ozone, and the control sample is significantly behind.

Specificities of the study of physical and chemical treatment of wastewater with a significant content of synthetic phosphate-based detergents

The relevance of research. Despite the decrease in the total volume of sewage over the first decades of the 21st century in the territory of Ukraine, the nature of the contaminants that make up their composition has changed significantly. In particular, the content of phosphate compounds and ammonium nitrogen increased. The increase in the phosphate component of wastewater is caused by the widespread of synthetic phosphate-based detergents. Existing treatment facilities are not designed to remove significant volumes of phosphate compounds. That provokes the process of reservoirs eutrophication, their secondary contamination due to biological processes (catastrophic reproduction of cyanobacteria and rapid development of higher aquatic vegetation). Possible ways to solve this issue include: prohibition of the use of synthetic phosphate-based detergents; reconstruction of sewage treatment plants, which will enable effective retention of phosphate compounds; reconstruction of water treatment plants, which will enable to purify poor quality water from water sources and the combination of all these three ways, but not with the global prohibition of the use of synthetic phosphate-based detergents, but by increasing the extra charges for them to the level of phosphate-free detergents and subsidizing them for that. Research results. A number of physical and chemical methods based on the oxidation reactions of a model solution of synthetic detergent were investigated. In particular, such a promising area of new water purification technologies as the use of so-called advanced oxidation technologies (AOTs), in which strong oxidants are generated by electric discharges in the water-air environment or on the surface of a thin film of water. Ozonation was performed using an apparatus that combined cavitation treatment and ozonation. The results of organic component oxidation experimental studies of the model solution with the use of «Fenton» reagent, physical methods of purification (ozonation with cavitation, plasma treatment) and treatment with hydrogen peroxide are presented. Conclusions. The best oxidation effect of the organic component of the model solution was achieved with the use of «Fenton» reagent – 89.5 %. All physical methods (cavitation with ozonation and plasma treatment) achieved about 50 % reduction in COD content: ozonation - 58.3 %; plasma treatment - 51.3 %. The worst results were obtained when treating with hydrogen peroxide - 1.78 %. The experiments in this area need to be continued because all the methods that have been tested require further water purification. In our view, it may be advantageous to combine physical treatment methods with «Fenton» reagent or with additional adsorption of organic compounds residues or with additional biological treatment.

Hydrodynamic cavitation of raw milk: Effects on microbial inactivation, physical and functional properties

The effects of hydrodynamic cavitation treatment of raw milk at different temperatures (outlet temperatures of 40, 50, 60 or 72 °C) were evaluated in relation to corresponding reference heat treatments. Physical and functional changes were studied and microbial inactivation was evaluated by the total bacterial count. Hydrodynamic cavitation reduced the mean milk fat globule size to 3.29–1.40 μm, depending on the treatment temperature. Treatment did not result in a significant increase in whey protein denaturation and did not affect acid gel formation. A reduction of >1 log unit in the total bacterial count was obtained, which was primarily ascribed to the temperature increase during treatment. Thus, this study illustrates that HC treatment can provide a heating unit allowing for simultaneous pasteurisation and reduction in MFG size, with minimal changes to the physical and functional properties of the milk.

Development of Peat Processing Methods for Production of Innovative Products

Synthesis or humification of humic substances (HSs) is the second widely applied organic compound transformation process after photosynthesis. Peat decomposition process results in a production of a HSs which has a high demand in agriculture, forestry, and gardening areas. Addition of the KOH is good option for environmental protection and K+ belongs to the nitrogen, potassium and phosphorous (NKP) mineral component. A homogenization process in a customize for commerce, where peat treatment technology was improved with the help of the cavitation effect. This effect was provided with the help of the high-speed mixer-disperser (HSMD) developed at Riga Technical University. Mechanical cavitation causes relatively high energy shifts from mechanical movement of cavitation causing elements to the liquid medium which causes efficient destruction of particles inside a suspension. Values of the peat particle diameter at 50 % in the cumulative distribution before and after 1, 2, and 3 homogenization cycles were measured in the present study. The aim of the present study was to find the optimal conditions (KOH concentration, cavitation cycles and reaction temperature) to produce potassium humate (K-HSs) regarding sustainable regenerative approach aspects. Cavitation treatment of the tested peat particle diameter at 50 % in the cumulative distribution (d50) from 267 down to 129 µm; the peak in the size range from 160 up to 409 µm completely disappears and significantly decreases the number of Dalton’s which causes the more efficient formation of fulvic acid caused by increased concentration of carbonyl and carboxyl groups as compared with the conventional homogenization method.

Intensified degradation of textile wastewater using a novel treatment of hydrodynamic cavitation with the combination of ozone

Abstract Ozone has been applied for the advanced treatment of textile wastewater containing a large number of indigestible dyes and other macromolecular organics. However, due to the poor mass transfer performance of ozone, the efficiency of ozonation was limited, resulted in high operating cost. In the present work, the degradation of dyes and real textile wastewater by hydrodynamic cavitation combined with ozone (HC + O3) was studied in a small-scale pilot plant operating at a capacity of 40 L. The treatment of single HC and HC + Air had minute dye removal within 180 min whereas the treatment of HC + O3 and single O3 could degrade the dyes effectively in 10 min. The removal efficiency of dyes followed the order HC + O3 > single O3 > HC + Air > single HC. The synergetic coefficient of HC + O3 was 1.33, which indicated that HC and O3 had noteworthy synergistic effect in the hybrid system. For the real textile wastewater, the removal rates of HC + O3 on COD, TOC, UV254 and color were 36%, 23%, 71% and 90% in 30 min, which was higher than the single treatment. The removal of UV254 and color showed that macromolecular organics and residual dyes were effectively degraded. Among these treatments, HC + O3 was the most energy-efficient. Therefore, HC + O3 could be used as a potential dye degradation technology and would have a promising engineering application value in the real textile wastewater advanced treatment.

ПРОЦЕСС ПОЛИМЕРИЗАЦИИ СТИРОЛА ПОД ДЕЙСТВИЕМ АКУСТИЧЕСКОГО ИЗЛУЧЕНИЯ

Cavitation treatment in the suspension polymerization of styrene leads to an increase in the yield of the finished product