Screening of Surfactants for Flooding at High-Mineralization Conditions: Two Production Zones of Carbonate Reservoir

The selection of effective surfactants potentially can mobilize oil up to 50% of residuals in mature carbonate oilfields. Surfactants’ screening for such oilfields usually is complicated by the high salinity of water, high lipophilicity of the rock surface, and the heterogeneous structure. A consideration of features of the oilfield properties, as well as separate production zones, can increase the deep insight of surfactants’ influence and increase the effectiveness of surfactant flooding. This article is devoted to the screening of surfactants for two production zones (Bashkirian and Vereian) of the Ivinskoe carbonate oilfield with high water salinity and heterogeneity. The standard core study of both production zones revealed no significant differences in permeability and porosity. On the other hand, an X-ray study of core samples showed differences in their structure and the presence of microporosity in the Bashkirian stage. The effectiveness of four different types of surfactants and surfactant blends were evaluated for both production zones by two different oil displacement mechanisms: spontaneous imbibition and filtration experiments. Results showed the higher effect of surfactants on wettability alteration and imbibition mechanisms for the Bashkirian cores with microporosity and a higher oil displacement factor in the flooding experiments for the Vereian homogeneous cores with lower oil viscosity.

Design Researches in Making In-Situ Thermal Foam System as a New Enhanced Heavy Oil Recovery Method

The paper presents the results of lab and filtration studies aimed at improving the procedure of thermal/gas/chemical effect (TGCE) with the generation of thermogenic system in reservoir conditions, proposed as an alternative to the methods of increasing oil recovery, such as water-gas effect procedure and foam injection process. The objects of research were thermal/gas generating compositions at the basis of sodium salts of sulfamic and nitric acids. Moreover, the influence of the ionic composition of the aqueous solution and temperature on the surface properties of the attracted solutions of surfactants (surfactants) was also evaluated. Filtration tests have shown that the use of a thermal/gas generating composition leads to additional displacement of high-viscous oil. The introduction of surfactants in the thermal/gas generating composition promotes foaming in the porous medium of the reservoir model and prevents gas breakthrough that leads to an increase in the oil displacement factor up to 24 %.

Wood product carbon substitution benefits: a critical review of assumptions

Background There are high estimates of the potential climate change mitigation opportunity of using wood products. A significant part of those estimates depends on long-lived wood products in the construction sector replacing concrete, steel, and other non-renewable goods. Often the climate change mitigation benefits of this substitution are presented and quantified in the form of displacement factors. A displacement factor is numerically quantified as the reduction in emissions achieved per unit of wood used, representing the efficiency of biomass in decreasing greenhouse gas emissions. The substitution benefit for a given wood use scenario is then represented as the estimated change in emissions from baseline in a study’s modelling framework. The purpose of this review is to identify and assess the central economic and technical assumptions underlying forest carbon accounting and life cycle assessments that use displacement factors or similar simple methods. Main text Four assumptions in the way displacement factors are employed are analyzed: (1) changes in harvest or production rates will lead to a corresponding change in consumption of wood products, (2) wood building products are substitutable for concrete and steel, (3) the same mix of products could be produced from increased harvest rates, and (4) there are no market responses to increased wood use. Conclusions After outlining these assumptions, we conclude suggesting that many studies assessing forest management or products for climate change mitigation depend on a suite of assumptions that the literature either does not support or only partially supports. Therefore, we encourage the research community to develop a more sophisticated model of the building sectors and their products. In the meantime, recognizing these assumptions has allowed us to identify some structural, production, and policy-based changes to the construction industry that could help realize the climate change mitigation potential of wood products.

Petroleum sulfonates of the karpatol trademark as the most effective surfactants for acting on the formation of producing wells

Experimental studies and pilot test results of developed stimulation technologies with petroleum sulfonate indicate economic benefits of the use of Karpatol achieved due to significant reduction in interfacial tension surfactant-hydrocarbon (oil, condensate, petrol); increase of residual oil displacement factor, destruction of water-oil emulsions, partial permeability build-up of contaminated rock samples, advanced permeability of surfactants in nonuniform permeable and hydrophobic strata, influence on the rheology of viscous oils, improvement of wells development after stimulation, high technological efficiency of stimulation technologies using Karpatol, increase of production index after treatment.

Closed-Horizontal Rotating Burner Development for Optimizing Plam Shell Charcoal (PSC) Production

Activated Carbon (AC) was produced through several stages such as carbonization, crushing and activation process. The critical part of AC production was located at carbonization process due to burner issues that need to complete burning in short time, appropriate temperature and low cost. Therefore, this research focus on developing burner which called by closed-horizontal rotating burner. The dimension of the burner was 65 x 790 mm (D x L) wih the capacity of 30 kg/carbonization process. This burner need 1 hour for complete burning of palm shell to palm shell charcoal (PSC). Several analysis were conducted such as stress, displacement, factor of safety and thermal analysis. because this burner involved in rotation motion and high temperature operation. Physical properties has been measured which consists of moisture content (3.8-5%), ash content (7.7-8%), volatile content (53.7-56.6%) and fixed carbon content (31.3-34.7%). It can be summarized that this burner was very effective to produce PSC with short time carbonization process, low cost and complete charcoal production.

Development of four quadrant operation of DC to DC converter using single phase matrix converter

<span>Single-Phase Matrix Converter (SPMC) is an advanced circuit topology that offer advantages such as the capability to regenerate energy back to the input, sinusoidal input and output current and a manageable input current displacement factor. By considering the opportunity of an advanced SPMC topology, further exploration on DC to DC operation is proposed. The four-quadrant operation of switching algorithm was developed to control the SPMC circuit. The voltage and current profile of each quadrant was investigated to validate the proposed switching control algorithm. As part of four quadrants DC to DC operation, the safe commutation switching algorithm was also developed in order to solve the commutation problem due to the used of an inductive load. The pulse width modulation (PWM) techniques was utilized to synthesize the output of the proposed converter. Results from MATLAB/Simulink are presented to validate the proposed circuit operation.</span>

Review of AC-DC power electronic converter topologies for power factor correction

<p>Increased harmonic content and low power factor in power systems caused by power converters have been of great concern. To overcome this, several converter topologies employing advanced semiconductor devices and control schemes have been proposed. The aim of this paper is to identify a low cost, small size, efficient and reliable ac to dc converter to meet the input performance index of uninterrupted power supply. In this paper, comparison between three converters namely AC-DC Cuk rectifier, Fly back converter &amp; Interleaved SEPIC converter have been carried out. For the above converters both bridged and bridgeless topologies have been analysed. The working of all the three types of converter has been illustrated with relevant waveforms followed by the simulation results. Comparison of the three converters have been done based on the parameters namely Displacement Factor, Supply Power Factor&amp; supply THD. The results are verified.</p>