bluuebunny/crossref_metadata_2025_split huggingface dataset:
Modified Asphalt Binder with Natural Zeolite for Warm Mix Asphalt
Authors: Dubravský Marián , Mandula Ján 
Published: December 2015

Abstract
In recent years, warm mix asphalt (WMA) is becoming more and more used in the asphalt industry. WMA provide a whole range of benefits, whether economic, environmental and ecological. Lower energy consumption and less pollution is the most advantages of this asphalt mixture. The paper deals with the addition of natural zeolite into the sub base asphalt layers, which is the essential constituent in the construction of the road. Measurement is focused on basic physic – mechanical properties declared according to the catalog data sheets. The aim of this article is to demonstrate the ability of addition the natural zeolite into the all asphalt layers of asphalt pavement. All asphalt mixtures were compared with reference asphalt mixture, which was prepared in reference temperature.
The Idea of an Innovated Concept of the Košice Geothermal Project
Authors: Bujanská Alena , Böszörményi László 
Published: December 2015

Abstract
Slovakia has very limited amounts of fossil resources. However, it has a relatively high potential of geothermal energy which use is far below its possibilities. The most abundant geothermal resource, not only in Slovakia but throughout the central Europe, is Košice basin. Since the publication of the first ideas about the ambitious goal to exploit the geothermal potential of this site, 20 years has passed and three geothermal wells has been made but without any progress. In the article the authors present the idea of a fundamental change in the approach to improve the energy and economic efficiency of the project.
Application of Chemical Grouting as an Option of Removing Soil Moisture - a Case Study in the Reconstruction of the Church
Authors: Katunská Jana , Katunský Dušan 
Published: December 2015

Abstract
The article provides an analysis of removing moisture from the soil masonry walls. The chemical pressure insulation may be considered as one of the alternatives. This paper describes the chemical waterproofing and points to a case study, which is a small church in the town of Košice. Renovation of the church took place in two stages, made using pressure chemical insulation for chemical grouting of envelope masonry. The appropriateness and effectiveness of the applied chemical methods can be seen in the conclusions of this contribution.
Engineered Solution to Reduce the Impact of Lost Circulation During Drilling and Cementing in Rumaila Field, Iraq
Authors: Arshad Umar , Jain Bipin , Ramzan Muhammad , Alward Wassem , Diaz Lenin , Hasan Ibrahim , Aliyev Ali , Riji Chen 
Published: December 2015

Abstract
Over the last 60 years in the oil and gas industry, lost circulation has been the major nonproductive time (NPT) issue worldwide during well construction (12% of total NPT). According to industry figures, more than USD 2 billion are spent combating circulation loss each year. In the Rumaila field of Iraq, the NPT due to lost circulation is significant, estimated to be 46% of the total NPT recorded.
The Rumaila oil field is a super-giant oil field in southern Iraq; the field is estimated to contain 17 billion barrels, which accounts for 12% of Iraq's oil reserves. In the Rumaila field, at least 45% of the wells experience severe to total circulation loss at depths of 450 to 650 m true vertical depth (TVD) while drilling in the karst facies of the Dammam formation. Numerous strategies, requiring up to 24 days of rig time or 15 cement plugs in some extreme cases, have been applied by different service companies without consistent results. This has resulted in higher operating costs and delayed production. Some of the identified reasons for the low success rate are poor wellbore characterization, weak assessment of the problem, and improper execution.
The foundation of the proposed engineering and operational approach is the characterization of the wellbore with the caliper and formation image logs for better understanding of fractures and estimation of fracture volume. The approach also includes two cement slurry-type options—an increased slurry rheology with reduced density and a slurry with rapid gel strength development. The proposed approach is made complete with the engineered estimation of cement slurry volume, based on loss rate, and proper field deployment.
Developed on the basis of previous experiences and optimization of hydrostatic pressure, cement slurry rheology, and gel strength development, the engineered lost circulation solution significantly improves the lost circulation control results. Extended evaluation of cement plug jobs with the engineered design and proper execution has proven the effective impact of the solution, curing losses during the drilling phase (&lt;3 days). This solution has proven to be an effective and key element, contributing to the increased success rate of the subsequent primary cementing operation and overcoming the challenges of zonal isolation.
Sensitivity Analysis and Optimization of Alkaline-Surfactant Flooding in a Thin Clastic Reservoir
Authors: Ghadami Nader , Das Apurba K. , Tunio Kamran H. , Sabzabadi Ali 
Published: December 2015

AbstractChemical EOR is one of the promising methods to improve the oil recovery. However, due to high cost of the process, there are challenges to minimize the cost and maximize the oil recovery. Some influencing parameters should be taken into account in a systematic approach to find their impact on oil recovery and accordingly optimizing the process.In this study, we present a robust optimization workflow of alkaline-surfactant (AS) flooding into a thin clastic reservoir of a field in the Malay Basin. There are coreflood experiments and pilot tests on this field that can be quite helpful to provide a basis to find out the appropriate range of input parameters. Optimization work is based on response surface methodology (RSM) and particle swarm optimization (PSO) technique that aid us to indicate the optimum oil recovery from chemical flooding. In order to get the utmost advantage of this workflow, the waterflooding should be optimized prior to the chemical flooding optimization to maximize the sweep efficiency and oil recovery from the chemical flood.Evaluation of coreflood and pilot tests indicated that some parameters need supplementary evaluation to investigate their effect on reservoir performance and flow dynamics. These parameters include residual oil reduction by chemical, relative permeability curves, chemicals adsorption, chemical concentration, slug size, injection rate, and initiation time of chemical injection. Based on the result of tornado chart, residual oil reduction and injection rate exhibited highest and lowest impact on oil recovery. RSM was used to explore the relationship between input variables and objective function. Some design parameters such as chemical concentration, slug size and initiation time were examined in this stage. Afterwards, proxy models have been built using polynomial regression and neural network methods. The results showed that the proxy model by neural network method revealed better performance for prediction of the simulation results. The proxy model was used to calculate the oil recovery for any combination of input parameters. Besides, it was used to assess the parameter sensitivity and identify the impact of any input parameter on oil recovery. At the next stage, PSO method was utilized to optimize the oil recovery by chemical flooding. It was found that the optimized water injection rate and pattern for water flooding scenario need further optimization to improve the sweep efficiency and thereby oil recovery by AS flooding at later stage. Running numerous simulation cases is normally expected to optimize the process by conventional methods and the proposed PSO approach can be used to reduce the number of runs significantly. Sensitivity analysis provided a very good understanding about reserve ranges for the different influential parameters. Optimizing the cost of chemical flooding and improving oil recovery are other outcomes of this study.
Methanol Production Enhancement Using Captured Carbon Dioxide Injection
Authors: Abdelsalam Omar 
Published: December 2015

Abstract
Study had been conducted to enhance methanol production via CO2 injection. This injected CO2 will be recovered from existing Reformer Flue Gas. The advantage of CO2 injection had resulted in attractive economical outcome for methanol production.
In Addition, the crucial effect of Decreasing Greenhouse effect by decreasing the CO2 Gas missions and its environmental impact was a main target of this paper and design project.
Not only production increase is the remarkable achievement in this study, but also the CO2 source, which is recovered from existing steam reformer Flue Gas in any Methanol Production plant. Detailed Material and Energy Balance has been done over the whole plant before and after modification, Accompanied with Preliminary economic analysis to the project.
As a Brief description of the project: flue gas will be sucked from pre-reformer stack via blower, and then cooled down by direct contact with water. Next, flue gas will be treated in two-column absorption technology using amine-based solvent to capture CO2. Purified CO2 will be injected in the methanol process.
As a conclusion, the outcome was remarkable and the increase in the plant productivity was in average of 5%, CO2 Gas emissions released and did made use of it for the same plant.
CO2 Well Injectivity: Effect of Viscous Forces on Precipitated Minerals
Authors: Sokama-Neuyam Yen Adams , Ursin Jann Rune 
Published: December 2015

Abstract
Carbon Capture and Storage (CCS) is particularly attractive for the oil and gas industry due to the potential of Enhanced Oil Recovery (EOR). The presence of adequate well injectivity is identified as a prerequisite for CCS and CO2 EOR projects. Mineral precipitation in the vicinity of the well is suggested as a possible injectivity impairment mechanism. After mineral precipitation and formation dryout, continuous injection of CO2 into the formation could redistribute precipitates and alter injectivity. In this work, we investigated the effect of viscous force on precipitated minerals and the resulting consequences on permability and injectivity. The influence of supercritical CO2 injection rate, initial core permeability and saturating brine salinity were investigated. We observed that, injectivity impairment has a maximum immediately after mineral precipitation. Continuous injection of supercritical CO2 into the core after mineral precipitation is seen to reduce injectivity impairment induced by precipitated minerals. In most numerical and geochemical models, static injectivity impairment as a result of mineral precipitation is often assumed. Our findings suggest that injectivity remains dynamic throughout the injection process. Therefore, changes in CO2 injectivity after mineral precipitation could be complex to model and understanding of the processes is a good point to start.
Industrial Application for the Removal of Kinetic Hydrate Inhibitor (KHI) Co-Polymers from Produced Water Streams
Authors: Al Redoua Ali , Hamid Saed Abdul 
Published: December 2015

Abstract
To avoid hydrate formation, Kinetic Hydrate Inhibitor (KHI) is injected into the upstream wet gas pipelines. KHI eventually remains in the produced water which is treated for H2S and oil removal before it is re-injected into deep disposal wells. Industry regulators in the State of Qatar have concluded that the presence of KHI polymers in the injected wastewater leads to long term reservoir damage… Hence it is essential to remove KHI polymers from re-injected wastewater streams.
As there are no industrially proven technologies for removal of KHI, pilot tests were conducted for removal via evaporation. At the same time, futher options were being assessed by other operators, including Wet Air Oxidation and KHI replacement with MEG. All options were assessed on technical, economical, planning, environmental, and safety criteria. The evaporation technology was found to be most suitable.
The pilot tests showed that KHI can be removed via evaporation to produce a distillate stream, equal to more than 99% of the incoming flow, with KHI polymers residual concentration lower than the detection limit of 25 mg/l, which will be suitable for re-injection; plus a concentrate stream that includes the concentrated KHI polymers and other salts and solids.
The process scheme was developed during the FEED (Front End Engineering and Design) stage, as follows. First, a pre-treatment step ensures breaking of the emulsions and the removal of oil and sludge. This mainly consists of coagulation and pH adjustment tanks, Dissolved Air Flotation and centrifuge packages. This is followed by a two-stage evaporator package which incorporates mechanical vapor recompression, cross heat exchangers, coolers, and cleaning in place techniques. Two outlet streams are created as a result; one distillate stream (free from KHI) which is sent for deep well injection, and one concentrate stream (with KHI), which will be sent to the concentrate storage facilities and will be loaded onto trucks for incineration by a third party.
The removal of KHI from produced water streams using evaporation technology has never been done on an industrial scale. The success of this project would ensure that continuing the utilization of KHI products to avoid hydrate formations in the wet gas streams is suitable for the natural gas industry, whilst also avoiding any potential damage of the reservoirs in the long term.
Carbon Dioxide Sequestration in Coal Formations
Authors: Ibrahim Ahmed Farid , Nasr-El-Din Hisham A. 
Published: December 2015

Abstract
Carbon dioxide (CO2) is the major greenhouse gas emitted in all activities. CO2 sequestration in coal seams has become an attractive carbon sequestration technology where the injection of CO2 enhances methane production from coalbeds (ECBM), in addition to storing CO2. CO2 can be retained in coal via three ways: free gas within the pore space or fractures in the coal, adsorbed molecules on the organic surface of coal, and dissolved in groundwater within the coal.
This study investigates the effects of the salinity (NaCl) of coal seam water, injection flow rate, and CO2 state (formation pressure) on the CO2 sequestration in volatile bitumen coal. To achieve this objective; coreflood tests were conducted on different coal cores. The change in the effective water-coal permeability after CO2 injection was examined. Also, the displacement efficiency of water by CO2 was estimated. The experimental data was cross-matched with numerical simulation to estimate the relative permeability curves.
The coreflood experiments showed that the effective water permeability in coal decreased during CO2 injection due to its adsorption onto the coal surface, and reduction of the relative water permeability. Higher formation pressure led to permeability reduction as a result of higher CO2 adsorption onto the coal surface. The effective water permeability decreased by 8% at 50 psi back pressure, compared to 48% at 1100 psi back pressure. Furthermore, as the injection flow rate increased, the contact time of CO2 to the coal surface decreased. Hence, the CO2 adsorption to the coal matrix decreased and the change on effective water permeability slightly decreased. Specifically, the effective water permeability decreased by 48% at 1 cm3/min comparing to 41% at 4 cm3/min. As salt concentration increased, the change in pressure drop across the core slightly increased, but this effect decreased as formation pressure increased. As the water salinity increased, the coal become more CO2 wet, and the residual gas saturation increased. Based on these observations, the injection of CO2 into highly volatile bitumen coal seams for CO2 sequestration and ECBM purposes is more efficient as the salt concentration increases and high injection pressure.
Probabilistic History Matching in a Shallow Marine Deltaic System: A Frequentist Approach
Authors: Jimenez Eduardo A , Jin Long , Essen Gijs van , Kullberg Ingrid 
Published: December 2015

Abstract
Within recent years there have been significant research efforts towards building an ensemble of reservoir models to quantify subsurface uncertainty. The data assimilation and model calibration strategy is rapidly moving away from conditioning just a single model as in almost every forecast exercise the predictability of a single model is rather limited. In this paper we will present a frequentist inference basis for the dynamic data integration problem in subsurface modeling. Specifically, we’re after deriving small representative sets of reservoir images and how dynamic data affects them.
Our approach starts with screening a large ensemble of subsurface realizations holding between 104–106 members (or more) where we’re after representatives that are mutually different in terms of their relevant reservoir flow behavior. We propose a reduced representation of the probability distribution of the high-dimensional vector space of all reservoir images defined by flow-like snapshots. This process allows defining a metric space where it's possible to execute cluster analysis and/or heuristic sampling of the high-dimensional geologic space. The result of this stage is a smaller ensemble of dynamically unconditioned eigen-reservoirs without compromising uncertainty that can be used in any stage of field development planning that involves reservoir dynamics.
We have used derivative-based techniques available in our in-house simulator to deterministically history match the eigen-reservoirs and provide a solution to the dynamic data conditioning problem. We provide results of the workflow application in a shallow marine deltaic system where 28 years of production data has been successfully assimilated. Our results show a remarkable improvement in the predictability of reservoir models, which is a vital component in the entire hydrocarbon maturation cycle.
Near Surface Velocity Model of Dukhan Field from Multi-Physics Survey to Enhance PSDM Seismic Imaging
Authors: Setiyono K. , Gallo S. , Boulange C. , Bruere F. , Moreau F. , Rondeleux B. , Snow J. 
Published: December 2015

Abstract
Dukhan Field affords an opportunity to assess alternative near surface velocity modeling workflows that specifically integrate Microgravity (MGR) and Vertical Electrical Sounding (VES). A pilot study of the Dukhan seismic data demonstrates that integration of MGR/VES into Pre-Stack Depth Migration (PSDM) improves the fidelity of seismic images and results in an improved depth match.
In many giant carbonate reservoirs, variations in surface and near surface geology result in velocity issues that are not necessarily corrected by standard seismic data processing workflows. A novel approach integrates MGR and VES inversion into processing workflows. Initial calibration and testing of MGR/VES data were computed on a pilot area (165 sq.km) at Dukhan which improved the near surface geological model between the surface and the first observed seismic reflector - Simsima Formation. Processing sequences utilizing microgravity and resistivity inversion resulted in a new velocity model. Combined with structural information, the VES resistivity model constrained the gravity inversion in depth. Gardner and Faust equations facilitated building the final near surface velocity model.
The resultant MGR/VES PSDM pilot model improved the velocity model between the surface and top Simsima Formation based on 1) visible impact on the deeper structure obtained from imaging and 2) better fit between the seismic depth horizons and well measured depths. Based on the results of this study, QP acquired MGR/VES data over the entire Dukhan survey area and will utilize these data in any future PSDM full-field processing. Other giant carbonate reservoirs may benefit from utilizing this workflow to further refine and enhance seismic imaging.
Gas Driers KO Drum Design Shortfall
Authors: O'Neill Stephen , Whateley Thomas , Al Hajri Abdulla 
Published: December 2015

Abstract
The objective of this paper is to describe a deterioration that was observed in the performance of molecular sieve type Gas Driers, to summarize the work that was done to identify the root cause, to describe the modifications that were implemented to resolve this problem, and to explain the extent to which these modifications were effective in resolving this problem.
During early 2012 the pressure drop across the Gas Driers in two trains within the onshore gas processing facility in Ras Laffan began increasing at a faster rate than usual. This change correlated with an increase in the CO2 content of gas feeding the concerned Gas Driers. Through liaison with molecular sieve vendors, it was established that the accelerated rate of bed deterioration had been caused by liquids carryover from the upstream Driers Inlet Separator co-inciding with an increase in CO2 content of the gas. Since it was preferred to maintain the increased CO2 concentration of the gas, efforts were made to re-design the Driers Inlet Separator to minimize liquid carryover into the Gas Driers.
The effectiveness of gas/liquid separation in the existing Driers Inlet Separator was first assessed by means of computational fluid dynamics (CFD) studies conducted by a third party. These studies demonstrated that the separation efficiency of liquids from gas in the existing vessel was inadequate, and that the effectiveness of separation could be greatly enhanced by implementation of various internal modifications without the need to replace the existing vessels.
It was proposed to remove the existing vane pack from within this vessel and to install new internals including a vane type inlet distributor, mesh pad, and cyclone separators. The effectiveness of these new internals was first demonstrated using proprietary software by the same third party. Upon completion of detailed engineering, these internals were manufactured and installed within the existing vessels.
The rate at which molecular sieve deterioration occurs downstream of these modified Driers Inlet Separators was assessed, and details regarding the methodology for this assessment as well as the outcome of the assessment are provided.
This paper will be of interest to anyone involved in the design or operation of molecular sieve Gas Driers and upstream gas/liquid separation facilities. It will provide useful information regarding the importance of effective gas/liquid separation upstream of these Gas Driers, especially when the CO2 concentration of the gas is high. This paper also describes novel internals modifications that can be considered for implementation in existing two or three phase separators that do not provide adequate separation of liquids from gas.