Cavitation Technology Research Articles

The Use of Cavitation Technology in the Treatment of Spent Nuclear Fuel Processes

Are set out positive results of the application impulse cavitation technology for handling waste management reprocessing of spent nuclear fuel is to enhance the safety, durability, of their storage and dumping for improve strength of the cement compound. Is proposed for numerical model for calculating of the thermal container for long-term storage of radioactive waste allowing improve accuracy of calculations of data of the design for objects of waste storage. It was established experimentally that the use of cavitation allows to increase outlet poorly soluble components pulp compared to conventional recycling when extracting them out storage tanks.

Photoacoustic cavitation for theranostics: mechanism, current progress and applications

As an emerging cavitation technology, photoacoustic cavitation (PAC) means the formation of bubbles in liquids using focused laser and pre-established ultrasound synchronously. Its significant advantages include the decreased threshold of each modality and the precise location of cavitation determined by the focused laser. In this paper, a brief review of PAC is presented, including the physical mechanism description, the classic experimental technology, the representative results in variety of media, and its applications in biomedical imaging and therapy. Moreover, some preliminary results of PAC in perfluoropentane (PFP) liquid and PFP droplets investigated by passive cavitation detection (PCD) in our group are also presented.

Современные компоновки технологических схем очистки сточных вод с использованием кавитационной технологии

Современные компоновки технологических схем очистки сточных вод с использованием кавитационной технологии

Characteristics Study of Sewage Source Heat Pump System Based on Heat Transfer Enhancement and Acoustic Cavitation Decontamination

Put forward an application of ultrasonic cavitation technology of the sewage source heat pump system to solve the problem of controlling pollution and emphatically discusses the principle of acoustic cavitation and the effect, to conduct a feasibility analysis of Anti-fouling in sewage source heat pump sewage side. Through analysis principle of ultrasonic cavitation and heat transfer enhancement for carrying the experiment, study the pattern of scaling in heat exchange tube for different velocity and viscosity, effect in flow rate on the ultrasonic cleaning wastewater, Effect in ultrasonic treatment time on the descaling result. Obtain that it can enhancement transfer for 48%.

The Large Turbine Impeller Cavitation Technology of Integrated Prevention and Control Lancang River Basin

There is a large widespread cavitation turbine components. By using HVOF Stellite alloy coating technology, brushing epoxy technology, epoxy-coated steel wire technology, brazed carbide block technology, repeated welding technology integrated control over the water turbine components cavitation,effectively prevent the turbine parts water cavitation in running condition, improve the reliability of hydroelectric equipment..

Cavitation technology – A greener processing technique for the generation of pharmaceutical nanoemulsions

Novel nanoemulsion-based drug delivery systems (DDS) have been proposed as alternative and effective approach for the delivery of various types of poorly water-soluble drugs in the last decade. This nanoformulation strategy significantly improves the cell uptake and bioavailability of numerous hydrophobic drugs by increasing their solubility and dissolution rate, maintaining drug concentration within the therapeutic range by controlling the drug release rate, and reducing systemic side effects by targeting to specific disease site, thus offering a better patient compliance. To date, cavitation technology has emerged to be an energy-efficient and promising technique to generate such nanoscale emulsions encapsulating a variety of highly potent pharmaceutical agents that are water-insoluble. The micro-turbulent implosions of cavitation bubbles tear-off primary giant oily emulsion droplets to nano-scale, spontaneously leading to the formation of highly uniform drug contained nanodroplets. A substantial body of recent literatures in the field of nanoemulsions suggests that cavitation is a facile, cost-reducing yet safer generation tool, remarkably highlighting its industrial commercial viability in the development of designing novel nanocarriers or enhancing the properties of existing pharmaceutical products. In this review, the fundamentals of nanoemulsion and the principles involved in their formation are presented. The underlying mechanisms in the generation of pharmaceutical nanoemulsion under acoustic field as well as the advantages of using cavitation compared to the conventional techniques are also highlighted. This review focuses on recent nanoemulsion-based DDS development and how cavitation through ultrasound and hydrodynamic means is useful to generate the pharmaceutical grade nanoemulsions including the complex double or submicron multiple emulsions.

Study on Characteristics of Ultrasonic Descaling and Heat Transfer Enhancement in Sewage Source Heat Pump System

sewage heat exchanger is important to collect heat energy in sewage source heat pump system. Heat transfer enhancement effect is not obvious while the chemical methods and manual cleaning is applying to remove the heat exchangers fouling in the long-term operation. Here sets an ultrasonic incrustation removal physical model in heat exchanger structure to antiscaling and descaling simultaneously. The acoustic cavitation technology can be used in sewage source heat pump systems for the experimental results and decontamination rate reaches 50%.

Role of H2O2 in the fluctuating patterns of COD (chemical oxygen demand) during the treatment of palm oil mill effluent (POME) using pilot scale triple frequency ultrasound cavitation reactor

Palm oil mill effluent (POME) is a highly contaminating wastewater due to its high chemical oxygen demand (COD) and biochemical oxygen demand (BOD). Conventional treatment methods require longer residence time (10–15days) and higher operating cost. Owing to this, finding a suitable and efficient method for the treatment of POME is crucial. In this investigation, ultrasound cavitation technology has been used as an alternative technique to treat POME. Cavitation is the phenomenon of formation, growth and collapse of bubbles in a liquid. The end process of collapse leads to intense conditions of temperature and pressure and shock waves which assist various physical and chemical transformations. Two different ultrasound systems i.e. ultrasonic bath (37kHz) and a hexagonal triple frequency ultrasonic reactor (28, 40 and 70kHz) of 15L have been used. The results showed a fluctuating COD pattern (in between 45,000 and 60,000mg/L) while using ultrasound bath alone, whereas a non-fluctuating COD pattern with a final COD of 27,000mg/L was achieved when hydrogen peroxide was introduced. Similarly for the triple frequency ultrasound reactor, coupling all the three frequencies resulted into a final COD of 41,300mg/L compared to any other individual or combination of two frequencies. With the possibility of larger and continuous ultrasonic cavitational reactors, it is believed that this could be a promising and a fruitful green process engineering technique for the treatment of POME.

Optimization of a Multiple Impinging Jets Cavitation Reactor Using Zero‐Valent Iron Powder as Catalyst

AbstractThe effect of a combination of impinging jets and hydrodynamic cavitation technology was investigated by a multiple impinging jets cavitation reactor (MIJCR). Zero‐valent iron (ZVI) powder and rhodamine B were chosen as heterogeneous catalyst and model pollutant, respectively. ZVI addition resulted in more than five times higher decolorization efficiency compared to runs without ZVI. In situ generation of Fenton reagents suggested an advanced Fenton process to explain the enhancing effect of the applied catalyst. Impinging jets and aeration led to significant enhancement of the process, and optimum values of inter‐nozzle distance and initial catalyst concentration favored the decolorization of rhodamine B.

EXPERIMENTAL TEST-BENCH FOR RESEACHING PROPERTIES OF FUEL-LUBRICANT MATERIALS

Was founded that problem of cavitation technologies based on throttles is little known. Proposed designed and produced experimental test-bench for using, which can exploited for diagnostics properties of working fluids through the analysis of cavitation pressure fluctuations.

Preparation and Property of Epoxy Based Nano-SiO<sub>2</sub>/TiO<sub>2</sub>/Polyimide Hybrid Enhanced Sizing

Abstract: An epoxy based nano-SiO2/TiO2/polyimide hybrid enhanced sizing for carbon fiber was prepared by modified SiO2/TiO2precursor in PAA collosol with silane couple agent(WD-50) and eligibility surfactant via sol-gel reaction, and both ultrasonic cavitation and multi-complex technology were used during the process. The properties of PAA-SiO2-TiO2hybrid sizing and micro-morphology of carbon fiber surface were analyzed by FTIR, DSC, Particle Size Analyzer and STM. The results indicated that nanoscale SiO2•TiO2particles dispersed in the hybrid sizing film homogeneously, and a layer with nano particles was formed on carbon fiber surface after treated by the hybrid enhanceing sizing. The roughness was increased and interface properties of carbon fiber would be improved. At the same time both tensile strength and the interlaminar shear strength were increased obviously.

Study on Acoustic Cavitation and Magnetic Coupling Wax Control Technology

To solve the wax deposition problem of high-pour-point and high-waxy oil wells, a new acoustic cavitation and magnetic coupling shaft wax control technology was proposed. Experimental research and field tests were conducted. This wax control technology can achieve the purpose of freezing point depression, viscosity reduction by emulsification, and wax control through the combined effect of cavitation, acoustic vibration, and magnetic intensification. Laboratory experiments showed that after acoustic cavitation and magnetic coupling treatment, the viscosity reduction ratio of high-pour-point oil was over 25.5% at 30°C; the freezing point was decreased from 32°C to 27°C, a 15.6% reduction; the wax crystal structure of the oil samples was changed from crude, thick, and dense to fine, thin, and sparse. Field tests showed that the acoustic cavitation and magnetic coupling wax control device can significantly extend the well's wax deposit cycle by more than 30 days and reduce the wax thickness (Yumen Oilfield). Using this technology, the flushing period was extended more than two times, with a maximum up to nine times, and the normal production time was also prolonged (Zhundong Oilfield in Xinjiang). The results are useful for the popularization and application of the new shaft wax control technology for high-freezing-point and high-waxy oil wells.

Dynamic analysis on temperature evolution inside a single bubble due to hydrodynamic cavitation under turbulence

Considering such factors as liquid compressibility, surface tension, liquid viscosity, heat transfer through bubble wall and water vapor inside bubble, the temperature evolution and its influence factors inside a single cavitation bubble driven by turbulent pressure field are investigated by adopting dynamics method and regarding water as work medium. Detailed analysis is conducted to understand the effects of cavitation bubble equilibrium radius, operating and structural parameters of the orifice hydrodynamic cavitation reaction on the bubble collapse temperature. A comprehensive significant fitting equation is obtained to quickly forecast the bubble collapse temperature under various conditions. The achievements obtained may provide theoretical guidance and technical support for optimization design of hydrodynamic cavitation reactor and practical application of hydrodynamic cavitation technology.

Preparation of carbon-containing nanostructures by cavitation technology

Results are provided for a study of the effect of cavitation technology on the physical properties of carbon-containing material, i.e., heat-treated cellulose. Heat-treated cellulose powder is studied by x-ray phase analysis (XPA), EPR, etc. As a result of quite brief cavitation action on a low-concentration aqueous suspension of heat-treated cellulose, it is possible to prepare a nano-liquid, i.e., an aqueous suspension with features that exist for low-concentration aqueous suspension of fulleroids, which are promising for use in industrial technology.

湍流作用下可压缩液体中空化泡的动力学特性

Considering such factors as liquid viscosity, surface tension, liquid compressibility and turbulence, the dynamical behaviors of cavitation bubble in orifice plate hydrodynamic cavitation reactor are numerically investigated regarding water as work medium. Detailed analysis is conducted to understand the effects of turbulence, initial radius of cavitation bubble, downstream recovery pressure of the orifice plate, pipe diameter and orifice to pipe diameter ratio on the cavitation bubble dynamics and the pressure pulse caused by rapid shrinkage of cavitation bubble. Some new phenomena such as second growth of cavitation bubble radius are discovered. The achievements obtained in this work may provide theoretical guidance and technical support for the optimization design of hydrodynamic cavitation reactor and practical application of hydrodynamic cavitation technology.

Preparation of nitrogen-containing humic preparations from peat

The effects of the duration of cavitation treatment, the concentration of NH3, the amount of hydrogen peroxide, and the water duty on the nitrogen content the dry residue and the amount of organic substances in the liquid phase of the oxidation products of peat with hydrogen peroxide in an aqueous ammonia solution using a cavitation technology were studied. The elemental and functional-type compositions of isolated nitrogen-containing humic preparations were studied.

CaviGulation aims to refine the desalination process

Green-tech' company Cavitation Technologies Inc (CTI) is developing a system that is capable of removing pollutants from water. According to the firm, the use of CaviGulation (CG) offers advantages over membrane-based technology.

Dynamic behaviors of cavitation bubble for the steady cavitating flow

In this paper, by introducing the flow velocity item into the classical Rayleigh-Plesset dynamic equation, a new equation, which does not involve the time term and can describe the motion of cavitation bubble in the steady cavitating flow, has been obtained. By solving the new motion equation using Runge-Kutta fourth order method with adaptive step size control, the dynamic behaviors of cavitation bubble driven by the varying pressure field downstream of a venturi cavitation reactor are numerically simulated. The effects of liquid temperature (corresponding to the saturated vapor pressure of liquid), cavitation number and inlet pressure of venturi on radial motion of bubble and pressure pulse due to the radial motion are analyzed and discussed in detail. Some dynamic behaviors of bubble different from those in previous papers are displayed. In addition, the internal relationship between bubble dynamics and process intensification is also discussed. The simulation results reported in this work reveal the variation laws of cavitation intensity with the flow conditions of liquid, and will lay a foundation for the practical application of hydrodynamic cavitation technology.

High-rate calcium removal using the Hyperkinetic Vortex Crystallization (HVC) process for reuse of electronics wastewater

The Hyperkinetic Vortex Crystallization (HVC) process using hydrodynamic cavitation technology was investigated to remove high calcium levels from the effluent of the fluoride removal process used in a semiconductor manufacturing company. Due to low alkalinity in the effluent of this wastewater, addition of sodium carbonate was necessary. The relatively stable effluent calcium concentration of 8.0–52.8 mg/L was achieved although the influent calcium concentration severely fluctuated in the range of 173–371 mg/L. A calcium removal efficiency of 84.5–97.0% was determined with the HVC process. To confirm the cavitation effect, the calcium removal process was operated with and without the use of the VRTX cavitation system. The calcium removal efficiency increased from 63.5% to 91.7% when the VRTX unit was operating. The change of the calcite shape from plate to a spherical form by VRTX application was also observed. This can enhance calcium removal because of the larger specific surface area for adsorption of newly produced colloidal calcites. The conversion of the calcite shape to spherical would also prevent (limit) formation of calcite scale in the inner wall of pipes and reactors.

Cavitation technologies for dispergation and homogenization

The results of tests carried out in industrial conditions are presented. They allow one to propose cavitation technologies of dispergation and homogenization for fabricating emulsions and suspensions under the action of ultrasonic, hydrodynamic, and hydroacoustic cavitation. The dispergation regimes were found for materials with various physicochemical properties, including viscous media (natural juices with pulp) and materials with a lamella structure (bentonite). Cavitation effects intensify dispergation processes and allow one to produce materials with submicronic dimension of the particles; this considerably increases the sedimentation period of the suspensions.