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Application of sorbents is one of most promising methods for removal oil spills from water surface. Plant fibres (kapok, straw, rice husks, nutshells) are very popular due to their availability and biodegradability. The disadvantage of these materials is their low selectivity towards water. One of the methods of modifying the surface properties of materials is the immobilization of controlled nanoparticles on the surface. In this way, plant fibres are used as a cheap carrier and the introduced nanoparticles improve medium’s sorption properties (make the surface hydrophobic, increase the specific area of the sorbent). The unmodified sunflower parenchyma is a bio-waste from agriculture with interesting structural properties. The material has a highly porous, ordered, spongy, honeycomb-like structure. To date, it has not been studied as potential sorbent for hydrocarbons removal from aquatic environment. SiO2-sunflower pith nanocomposite was prepared via impregnation of hydrophobic SiO2 nanoparticles on pith surface using polydimethylsiloxane (PDMS) as coupling agent and its performance in the removal of toluene from water was investigated. The prepared nanocomposite was characterized using SEM and FTIR analyses confirming the deposition of SiO2 nanoparticles throughout the heterogeneous surface of pith. The maximum sorption capacities of raw and modified parenchyma were 3.54 and 4.18 g/g, respectively. The batch equilibrium data were fitted well by Temkin and Toth equations. This proves the heterogeneity of the sorbent surface and the possibility of forming an adsorbate polylayer. The rate of adsorption increases with temperature rising from 20 to 40°C, but the maximum equilibrium sorption capacity decreases due to an increased solubility of toluene in water. The present findings indicate that the sunflower biomass could be a potential alternative as sorbent precursors for hydrocarbons removal from polluted wastewaters. [ABSTRACT FROM AUTHOR]

In order to produce crude oil three recovery techniques are used: primary, second and tertiary also known as Enhanced Oil Recovery (EOR). Oil production in the Carpatian region is difficult due to the long-term production and significant depletion of reservoir energy. One of the methods that are considered to increase oil recovery factor is CO2-EOR. This method is based on carbon dioxide injection into oil reservoir in order to maintain reservoir pressure and modify physicochemical oil properties. Combination of this method with geological sequestration of carbon dioxide (CCS) relying on its storage in geological structures implemented after the end of production stage brings additional benefits in terms of environmental protection and extends the reservoir life, which translates into a positive economic effect. In this paper an analysis of the possibilities of the CCS-EOR method application on one of the Carpathian oil fields is carried out. Suitable location of injection wells and proper selection of carbon dioxide injection parameters allow a significant increase in the cumulative oil production from the analyzed reservoir what enhances oil recovery factor by 3 percentage points over the 20 years of the forecast. [ABSTRACT FROM AUTHOR]

In comparison to other countries of the Southern Caucasus, Armenia is the country with the least number of people, the smallest territory, landlocked, dependent on external energy supply. Armenia is also engaged in the military conflict in the area of neighboring Azerbaijan to defend the interests of Armenian living there. Armenia hasn't got its own fossil energy sources and it is also not a transit country, which transit oil and natural gas through its territory. Therefore, this country is heavily dependent on energy imports. In 2012, 90% of the country's energy needs were met by import. In that situation, the energy security of Armenia is the second key challenge, next to the military one, for its modern policy. The import share in Armenia's total energy demand is slightly fluctuating depending on the hydropower potential: in the dry period, import volume is increasing. Armenia has a big renewable energy potential that could become the guarantee of energy security and of diversification of energy resources. [ABSTRACT FROM AUTHOR]

Carbon capture storage (CCS) technology is expected to help reduce the anthropogenic carbon dioxide emissions, however, application requires finding the rock formations with sufficiently large storage capacities. Water-bearing formation allow to store a highvolume CO2. Nevertheless, the assessment of the capacity of aquifers structures remains a problem. In this work reservoir simulation was developed to estimate CO2- storage capacity because it allowed to take into account the effect of heterogeneity in an aquifer and actual aquifer geometry, migration of CO2 by advection and buoyancy, well location, injection interval, variable injection scenarios, residual trapping of CO2 in brine, and permeability reduction due to salt ions precipitation. Results showed that the efficiency of CO2 storage in the selected geological closed structure (aquifer) increased with the increase in the number of wells and at the same time the expenses of injection. For the analyzed variants, the rise in reservoir pressure did not exceed 2.5 MPa, which accounted 12% of the average reservoir pressure. The maximum pressure increase cannot be higher than 15% of the reservoir pressure what may result in fracturing of the storage sealing structure. The results of the simulation revealed that 10 billion cubic feet of carbon dioxide can be safely injected to the Marianowo Anticline. Analysis of water pH changes indicated that the value of this parameter decreased the most around the injection wells zone because of gas dissolving in water. Sensitivity analysis showed that the amount of carbon dioxide influenced the efficiency of the storage process. [ABSTRACT FROM AUTHOR]

The collapse of the USSR has become a great opportunity for Azerbaijan to initiate and develop energy cooperation with the West because it is a country with large oil and gas reserves. After signing of "deal of the century" in 1994 first inflow of foreign capital allowed the development of new fields (Azerri-Czirag-Guneszli), building independent transmission network of energy resources to Europe (pipelines Baku-SUPSA, BTC and BTE), improving the condition of the Azerbaijani economy and the strengthening of Azerbaijan's international position. Azerbaijan's dependence on export sales of energy resources also had negative consequences, such as "Dutch Disease" and increased susceptibility to the volatility of prices of energy resources on the world market. These phenomena was a derivative of the lack of structural reform of the national economy during prosperity time. Only a small portion of difficult economic situations during the crisis was improved by the SOFAZ oil fund, whose resources are currently running out. At the same time, the decline in domestic oil production in recent years will bring Azerbaijan into the category of transit countries. [ABSTRACT FROM AUTHOR]

Wettability as a rock-fluid interaction property is well recognized to affect the multiphase flow in hydrocarbons reservoirs. It impacts on the petrophysical properties of reservoir rock including relative permeability, capillary pressure, electrical properties and enhanced oil recovery. The three most commonly states are differed of wettability for hydrocarbon fields, these include: water wet, oil wet and mixed. USBM and Amott-Harvey laboratory methods are proposed as petroleum industry standards to estimate rock wettability in laboratory conditions. The first technique is directly calculated from area under capillary pressure curves and the second is related to spontaneous and forced characteristics of drainage and imbibition processes. Most oil reservoir rocks are characterized by water-wet since they were formed in marine environments. Generally, carbonate rocks have a moderate to strong oil-wet character of wettability. During oil production reservoir rock can reverse from water-wet towards oil-wet condition because of the solid particles which attract negatively charged chemical compound contained in the migrating hydrocarbon phase. Laboratory measurement of wettability at reservoir conditions is a key factor for the success of EOR application on the oil field. In presented work, the determination of wettability at laboratory environment on standard sandstone and dolomite core plugs by Amott-Harvey test was carried out. These rock samples correspond to the main oil bearing formations which are taken into account as the potential EOR candidates. The obtained results show wettability for sandstone as water-wet and oil-wet for dolomite rock. In this paper determination of wettability is considered as a one of multiple preliminary factors considered as crucial parameter during selecting IOR and EOR method application for the Polish oil fields. For sandstone rocks IOR methods based on water flooding are recommended and EOR methods, especially gas injection are selected for dolomite formations. The proper understanding of the wettability of the reservoir is essential for determining the most efficient way of oil production. [ABSTRACT FROM AUTHOR]

The application of enhanced oil recovery processes (EOR -- Enhanced Oil Recovery) on oil fields increases the recovery efficiency. This is especially important in depleted and mature fields. This should result in production increase by raising the recovery factor. Depending on the technology used and techniques applied in the field, the methods can be divided into thermal, gas injection or chemical methods. The CO2 injection method is very popular in the U.S.A. The production of cheap gas from natural sources and availability of pipelines connecting gas sources make this process economically attractive. There are 84 documented oil fields in Poland. Most of them have been exploited for many years with a relatively low recovery factor. This implies a considerable potential of production increase, even if no new bigger fields were to be found. At present advanced recovery methods are not used in Poland; only secondary methods are employed in several fields. This means that much can still be done in this area. Application of CO2-EOR method requires adequate wells preparation. EOR injection wells may be either drilled as new wells or, as is quite common in existing fields, re-completed by converting an existing producing well or a water injection well to a specific fluid injector. CO2 sequestration wells require detailed consideration of the well integrity in every aspect of the well design, construction, operation, monitoring, condition evaluation, workover, suspension and abandonment. New application may be based on international experience with miscible flood and WAG injection with CO2 and polish experience with acid gas injection and underground gas storage. [ABSTRACT FROM AUTHOR]