Vladimir O. Abramov

Extraction of bitumen, crude oil and its products from tar sand and contaminated sandy soil under effect of ultrasound.

In the present paper, the kinetics of the water extraction of bitumen from tar sand and crude oil or residual fuel oil from model contaminated soils under the effect of ultrasound is studied. The influence of process temperature, ultrasound power, the nature, and properties of the components of heterogeneous mixtures being separated, and the concentration of added alkaline reagents on the rate and degree of oil recovery is investigated. A functional form of the dependencies of separation efficiency on the mean size of solid particles and the temperature of a working medium is found. Optimum concentrations of reagents in the process solution are determined. It is shown that the spent solution of sodium silicate can be multiply used for separation, its reuse even speeding up the yield of oil in the initial period. Taking into account obtained results, a multipurpose pilot plant with a flow-type reactor for ultrasonic extraction of petroleum and its products from contaminated soils was manufactured and tested. During tests, the purification of sandy soil contaminated with residual fuel oil was carried out which verified the results of laboratory studies.

Ultrasonic technology for enhanced oil recovery from failing oil wells and the equipment for its implemention

A new method for the ultrasonic enhancement of oil recovery from failing wells is described. The technology involves lowering a source of power ultrasound to the bottom of the well either for a short treatment before removal or as a permanent placement for intermittent use. In wells where the permeability is above 20 mD and the porosity is greater than 15% ultrasonic treatment can increase oil production by up to 50% and in some cases even more. For wells of lower permeability and porosity ultrasonic treatment alone is less successful but high production rates can be achieved when ultrasound is applied in conjunction with chemicals. An average productivity increase of nearly 3 fold can be achieved for this type of production well using the combined ultrasound with chemical treatment technology.

Sonochemical approaches to enhanced oil recovery

Oil production from wells reduces with time and the well becomes uneconomic unless enhanced oil recovery (EOR) methods are applied. There are a number of methods currently available and each has specific advantages and disadvantages depending on conditions. Currently there is a big demand for new or improved technologies in this field, the hope is that these might also be applicable to wells which have already been the subject of EOR. The sonochemical method of EOR is one of the most promising methods and is important in that it can also be applied for the treatment of horizontal wells. The present article reports the theoretical background of the developed sonochemical technology for EOR in horizontal wells; describes the requirements to the equipment needed to embody the technology. The results of the first field tests of the technology are reported.

Laser and Electric Arc Synthesis of Nanocrystalline Scintillators

Two new methods of preparation of nanocrystalline scintillators are described. Laser ablation of microscopic powders immersed in optically transparent liquid was used to produce spherical nanoparticles, which preserved the initial compositions. Electric arc discharge between electrodes of definite metals immersed in water solutions of different salts produces a vast variety of scintillating compounds with nanoscopic dimensions and morphologies having crystallographic symmetry of the corresponding equilibrium phases. A wide range of different compositions and structures of tungsten oxides are obtained during one synthesis process, which is due to variety of temperatures and other conditions around the arc channel. It was found that the light emission spectroscopy of the discharge is a rather informative method of diagnostics of the process of the nanoparticle synthesis inside the discharge chamber. The synthesis of nanoscintillators by arc discharge turned out to be rather efficient and capable to create nanocrystalline scintillators of easily regulated compositions. Hydrogen injection into nanoparticles of tungsten oxide is detected by light emission and infrared absorption spectroscopy. Hydrogenated nanoscintillators obtained by this method are interesting for registration of fast neutrons.

Ultrasonically improved galvanochemical technology for the remediation of industrial wastewater

Two general methodologies adopted for the decontamination of industrial wastewater containing oil and metal ions are flocculation and coagulation. Both methods require the addition of chemicals and in the case of electrocoagulation the additional use of electrical power. Another methodology that was developed in Russia some years ago involves the production of Fe2O3 particles as coagulants by a galvanochemical reaction between iron and coke. Both of these materials are inexpensive and generally available in bulk. Ultrasonic processing of the particles generated in this reaction reduces the particle size of the Fe2O3 particles and provides surface cleaning making them more effective. Trials have proved their efficiency for the decontamination of wastewater made up in a laboratory and real wastewater from a carriage cleaning station on the St. Petersburg Metro. A mathematical model for the process has been developed.

Ultrasonic technologies for extracting oil products from oil-bearing sands and contaminated soils

The kinetics of the extraction of oil products (bitumen, oil, and fuel oil) from natural and model oil-bearing sands after ultrasonic treatment was studied. The effects of the process temperature, the nature and properties of the separated components, and the concentrations of the added reagents on the rate and extent of oil product extraction were also studied. The functional form of the dependences of the separation efficiency on the mean size of the solid particles and the working medium temperature was determined. The working solution of sodium silicate can be recycled in the separation, and its reuse can even accelerate the extraction of oil products at the first stage. Based on the obtained data, we created and tested a universal pilot apparatus for ultrasonic oil extraction from oil-bearing sands and the purification of soils contaminated with oil products.

Acoustic and sonochemical methods for altering the viscosity of oil during recovery and pipeline transportation

Reduction of oil viscosity is of great importance for the petroleum industry since it contributes a lot to the facilitation of pipeline transportation of oil. This study analyzes the capability of acoustic waves to decrease the viscosity of oil during its commercial production. Three types of equipment were tested: an ultrasonic emitter that is located directly in the well and affects oil during its production and two types of acoustic machines to be located at the wellhead and perform acoustic treatment after oil extraction: a setup for ultrasonic hydrodynamic treatment and a flow-through ultrasonic reactor. In our case, the two acoustic machines were rebuilt and tested in the laboratory. The viscosity of oil was measured before and after both types of acoustic treatment; and 2, 24 and 48h after ultrasonic treatment and 1 and 4h after hydrodynamic treatment in order to estimate the constancy of viscosity reduction. The viscosity reduction achieved by acoustic waves was compared to the viscosity reduction achieved by acoustic waves jointly with solvents. It was shown, that regardless of the form of powerful acoustic impact, a long lasting decrease in viscosity can be obtained only if sonochemical treatment is used. Using sonochemical treatment based on ultrasonic hydrodynamic treatment a viscosity reduction by 72,46% was achieved. However, the reduction in viscosity by 16%, which was demonstrated using the ultrasonic downhole tool in the well without addition of chemicals, is high enough to facilitate the production of viscous hydrocarbons.

An ultrasonic technology for production of antibacterial nanomaterials and their coating on textiles.

Summary A method for the production of antibacterial ZnO nanoparticles has been developed. The technique combines passing an electric current with simultaneous application of ultrasonic waves. By using high-power ultrasound a cavitation zone is created between two zinc electrodes. This leads to the possibility to create a spatial electrical discharge in water. Creation of such discharge leads to the depletion of the electrodes and the formation of ZnO nanoparticles, which demonstrate antibacterial properties. At the end of this reaction the suspension of ZnO nanoparticles is transported to a specially developed ultrasonic reactor, in which the nanoparticles are deposited on the textile. The nanoparticles are embedded into the fibres by the cavitation jets, which are formed by asymmetrically collapsing bubbles in the presence of a solid surface and are directed towards the surface of textile at very high velocities. Fabrics coated with ZnO nanoparticles by using the developed method showed good antibacterial activity against E. coli.

Ultrasonic activation of reagent purification of surface wastewaters from oil products

Reagent purification of water from oil contaminants can be intensified by preliminary ultrasonic short treatment of concentrated solutions. The major mechanism of the ultrasonic treatment of reagents is dispersion of coagulant and flocculant particles by cavitation. Based on the results of our studies, we chose the most suitable reagent and the optimum conditions of purification. The new acoustic reagent flotation technology is recommended for use in constructing waste disposal plants for surface water contaminated with oil products.

Determination of the technological parameters for the sonochemical purification of oily water

Ultrasound allows for the significant intensification of modern technologies, providing for the reduction of their energy capacity and the improvement of the quality of the final product. An experimentally revealed essential increase in the activity of crystals obtained in a galvanocoagulator upon ultrasonic exposure allowed for the elaboration of a new technology for the purification of large amounts of polluted waters in special reaction vessels. At the Institute of General and Inorganic Chemistry of Russian Academy of Sciences, a method for the purification of wastewaters from oil products and heavy metals using a galvanocoagulant as a reagent was developed. To realize this technique, flow drum reactors (galvanocoagulators) operating in a continuous mode by microferritization using magnetite, which is obtained by the electrochemical method directly in the rolling drums, are used.