LIQUEFACTION OF NIGDE-ULUKISLA OIL SHALE: THE EFFECTS OF PROCESS PARAMETERS ON THE CONVERSION OF LIQUEFACTION PRODUCTS

In this paper, the direct liquefaction of Turkish Nigde-Ulukisla oil shale in noncatalytic and catalytic conditions was studied. The effects of pressure, tetralin/oil shale ratio, catalyst type and concentration, reaction time and temperature and oil shale/waste paper ratio on the process were investigated. It was found that tetralin/oil shale ratio had no considerable effect on the total and liquefaction products conversions under the noncatalytic conditions. Fe2O3, MoO3, Mo(CO)(6), Cr(CO)(6) and zeolite were used as catalysts in catalytic liquefaction. The highest total and liquefaction products conversions were obtained using MoO3 as catalyst at a concentration of 9% by weight. Reaction temperature of 400 degrees C and reaction time of 90 minutes were chosen according to obtained liquefaction results. Co-liquefaction experiments were performed using waste paper. Both the total and oil + gas conversions were increased to a considerable extent by the application of the co-liquefaction process. According to gas chromatographic-mass spectrometric (GC-MS) analysis, the liquid product from the liquefaction process of oil shale under catalytic conditions of experiment 22 consisted mainly of naphthalene and its derivatives and polycyclic hydrocarbon such as indene and its derivatives

Experimental Investigation of Foam drilling fluid using Visualization Technique

Cutting transport is one of the major factors, which affects the cost, time and quality of drilling operations. Over the years, as the number of directional wells have increased to improve the productivity, it has been observed that cutting transport is more difficult in horizontal and directional wells as compared to vertical wells. While the foam/aerated drilling fluid provides significant advantages over conventional drilling fluid such as higher rate of penetration and reduction in formation damage, however these advantages are reduced due to inefficient cutting transport to the surface. This study investigates the effect of different parameters such as cuttings weight concentration, liquid flow rate and gas flow rate on cutting transport using foam/aerated drilling fluid. The experiments were conducted in a 6.16 m long horizontal pipe with 2.5 in. inner diameter and 4.5 in. outer diameter and annular diameter ratio of 1.8. The liquid and the gas flow rate was varied between 219 - 380 kg/min and 4 - 6.5 L/min, while the gas input pressure was kept constant at 2 bar. An anionic surfactant was used to stabilize the foam with a stationary liquid density of 818 kg/m3. The concentration of the borosilicate solid glass beads of 2-3 mm average diameter was varied between 0 - 4 wt. %. The results showed that increase in the liquid flow rate or Reynold number improved cutting transport, whereas increase in the gas flow rate and solid cuttings concentration decreased the cutting transport velocity for a constant gas input pressure. A non-dimensional performance parameter was introduced, for comparison of the cutting transport efficiency of different fluids such as water, 0.05 wt. % and 0.1 wt. % bio-polymer concentrations. It was observed that foam fluid has the highest bed height, Reynold number and lowest solid velocity (Reynold number). Performance parameter indicates that foam fluid has a better cutting transport efficiency as compared to bio-polymer based drilling fluid for horizontal drilling. This study can act as a guide to improve our knowledge of cutting transport and how cutting transport efficiency of different fluids can be compared using performance parameter

Method and system for stability determination of asphaltenes utilizing dielectric constant measurements

A method of determining if unstable asphaltenes are present in a crude oil sample includes obtaining a crude oil sample and performing a fractional analysis of the crude oil sample. In one embodiment, the method further includes measuring, via a cylindrical capacitor, a dielectric constant of the crude oil sample. Responsive to the measured dielectric constant, presence of unstable asphaltenes within the crude oil sample is determined. Responsive to the determined presence of unstable asphaltenes in an amount above a predetermined value, asphaltene precipitation is mitigated by addition of a chemical additive to the well.U

Utilization of Clay Minerals in Wastewater Treatment: Organic Matter Removal with Kaolinite

The aim of presented study is the investigation of clay minerals utilization in the wastewater treatment. The chemical treatability studies were carried out by the refined packing type kaolinite (hydrate aluminum silicate). By testing kaolinite as coagulant and flocculant separately within the experimental studies, optimum doses were determined, and on the basis of treatment efficiencies, results were compared with the chemicals such as alum, lime and ferric chloride which are widely used. The removal of organic matter was deter-mined according to Chemical Oxygen Demand (COD) parameter. Higher treatment efficiencies were obtained when kaolinite was used as flocculant. For the domestic wastewater, 82% organic matter, 70% suspended solids matter, and 23% oil-grease removals were achieved when alum was used as coagulant and kaolinite was used as flocculant. The turbidity of wastewater was removed completely, and insignificant differences were observed in pH parameter. For industrial wastewater samples, the highest efficiency was obtained when ferric chloride was used as coagulant and kaolinite was used as flocculant. In this case, 99% organic matter, 83% suspended solids matter, and 85% oil-grease removals were obtained. For the industrial wastewater treatment, the usage of kaolinite as coagulant yielded also efficient results, 96% COD removal was obtained

Design of flow control devices in steam-assisted gravity drainage (SAGD) completion

Abstract Commercialization of the steam-assisted gravity drainage (SAGD) process has made recovery of heavy oil/bitumen possible in a number of reservoirs hindered by hydrocarbon immobility. However, the economics of this process are highly sensitive to the efficiency of steam creation, delivery, and use, with a successful and unsuccessful SAGD well pair often separated by how effectively thermal inefficiencies can be mitigated in the flow profiles of steam injection and/or in emulsion recovery. To improve flow profiles, Albertan SAGD completions have experimented with the addition of flow control devices (FCDs). These completion tools have historically been used to regulate liquid inflow across long producing laterals, adding a variable pressure drop along the lateral to improve the conformance of hydrocarbon production and delay water breakthrough; within SAGD completions, FCDs find novel use to force a more even flow distribution of steam in the injector and a thermally dependent inflow profile in the producer to maximize recovery of heavy oil/bitumen. This paper provides a comprehensive overview of different FCD designs, discussing their respective methods of regulation, the fluid-adaptive behavior of “autonomous” FCDs, operational strengths and weaknesses of different commercial offerings, and suggestions on how to use existing pressure loss models for FCDs and apply them to the non-traditional application of regulating SAGD flow profiles, both for equipment sizing and estimation of pressure loss/flow rates across the device. From this work, it is proposed that use of autonomous FCDs in the production lateral are of greater value than use of flow control in the injector; however maximum benefits are achieved by coupling simple orifice-style FCDs in the injector lateral with autonomous, large flow path (non-orifice) FCDs capable of controlling steam flash events in the production well

Utilization of clay minerals in wastewater treatment: Organic matter removal with kaolinite

The aim of presented study is the investigation of clay minerals utilization in the wastewater treatment. The chemical treatability studies were carried out by the refined packing type kaolinite (hydrate aluminum silicate). By testing kaolinite as coagulant and flocculant separately within the experimental studies, optimum doses were determined, and on the basis of treatment efficiencies, results were compared with the chemicals such as alum, lime and ferric chloride which are widely used. The removal of organic matter was deter-mined according to Chemical Oxygen Demand (COD) parameter. Higher treatment efficiencies were obtained when kaolinite was used as flocculant. For the domestic wastewater, 82% organic matter, 70% suspended solids matter, and 23% oil-grease removals were achieved when alum was used as coagulant and kaolinite was used as flocculant. The turbidity of wastewater was removed completely, and insignificant differences were observed in pH parameter. For industrial wastewater samples, the highest efficiency was obtained when ferric chloride was used as coagulant and kaolinite was used as flocculant. In this case, 99% organic matter, 83% suspended solids matter, and 85% oil-grease removals were obtained. For the industrial wastewater treatment, the usage of kaolinite as coagulant yielded also efficient results, 96% COD removal was obtained

Method and system for stability determination of asphaltenes utilizing dielectric constant measurements

A method of determining asphaltene stability within a crude oil sample that includes obtaining a crude oil sample and performing a fractional analysis of the crude oil sample. The method further includes measuring, via a cylindrical capacitor, a dielectric constant of the crude oil sample and its fractions. Responsive to the measured dielectric constant, the stability of the asphaltenes within crude oil sample is determined.U

Recovery of Turkish Oil Shales by Electromagnetic Heating and Determination of the Dielectric Properties of Oil Shales by an Analytical Method

The effect of microwave irradiation on the recovery of three different oil shale samples was studied. To enhance the microwave efficiency, three different iron powders (Fe, Fe2O3, and FeCl3) and their three different doses (0.1, 0.5, and 1% by weight, each) were added to the samples as microwave receptors. The doses of each receptor were optimized for each oil shale sample based on the highest oil or gas production value obtained experimentally. During the experimental studies, the temperature distribution and the emissions of CO, H2S, CH4, and O-2 gases were recorded. Temperature distributions obtained experimentally,were modeled analytically to find the microwave power absorption coefficient of each Oil shale sample. Experimental and analytical studies show that, oil recovery From oil Shales is not Only related to reaching the pyrolysis temperature, but also to the amount of time that temperature is maintained. Therefore, for the efficient recovery of oil shales, the best solution is found in a hybrid utilization of irradiation and conventional heat transfer: microwave heating for a rapid temperature rise and conventional heating for sustaining high temperatures effectively