Removing of Formation Damage and Enhancement of Formation Productivity Using Environmentally Friendly Chemicals

Matrix acidizing is used in carbonate formations to create wormholes that connect the formation to the wellbore. Hydrochloric acid, organic acids, or mixtures of these acids are typically used in matrix acidizing treatments of carbonate reservoirs. However, the use of these acids in deep wells has some major drawbacks including high and uncontrolled reaction rate and corrosion to well tubulars, especially those made of chrome-based tubulars (Cr-13 and duplex steel), and these problems become severe at high temperatures. Hydrochloric acid (HCl) and its based fluids have a major drawback in stimulating shallow (low fracture gradient) formations as they may cause face dissolution (formation surface washout) if injected at low rates. The objective of stimulation of sandstone reservoirs is to remove the damage caused to the production zone during drilling or completion operations. Many problems may occur during sandstone acidizing with Hydrochloric/Hydrofluoric acids (HCl/HF) mud acid. Among those problems: decomposition of clays in HCl acids, precipitation of fluosilicates, the presence of carbonate can cause the precipitation of calcium fluorides, silica-gel filming, colloidal silica-gel precipitation, and mixing between various stages of the treatment. To overcome problems associated with strong acids, chelating agents were introduced and used in the field. However, major concerns with most of these chemicals are their limited dissolving power and negative environmental impact. Glutamic acid diacetic acid (GLDA) a newly developed environmentally friendly chelate was examined as stand-alone stimulation fluid in deep oil and gas wells. In this study we used GLDA to stimulate carbonate cores (calcite and dolomite). GLDA was also used to stimulate and remove the damage from different sandstone cores containing different compositions of clay minerals. Carbonate cores (calcite and dolomite) of 6 and 20 in. length and 1.5 in. diameter were used in the coreflood experiments. Coreflood experiments were run at temperatures ranging from 180 to 300oF. Ethylene diamine tetra acetic acid (EDTA), hydroxyl ethylethylene diaminetriacetic acid (HEDTA), and GLDA were used to stimulate and remove the damage from different sandstone cores at high temperatures. X-ray Computed Topography (CT) scans were used to determine the effectiveness of these fluids in stimulation calcite and dolomite cores and removing the damage from sandstone cores. The sandstone cores used in this study contain from 1 to 18 wt percent illite (swellable and migratable clay mineral). GLDA was found to be highly effective in creating wormholes over a wide range of pH (1.7-13) in calcite cores. Increasing temperature enhanced the reaction rate, more calcite was dissolved, and larger wormholes were formed for different pH with smaller volumes of GLDA solutions. GLDA has a prolonged activity and leads to a decreased surface spending resulting in face dissolution and therefore acts deeper in the formation. In addition, GLDA was very effective in creating wormholes in the dolomite core as it is a good chelate for magnesium. Coreflood experiments showed that at high pH values (pH =11) GLDA, HEDTA, and EDTA were almost the same in increasing the permeability of both Berea and Bandera sandstone cores. GLDA, HEDTA, and EDTA were compatible with Bandera sandstone cores which contains 10 wt percent Illite. The weight loss from the core was highest in case of HEDTA and lowest in case of GLDA at pH 11. At low pH values (pH =4) 0.6M GLDA performed better than 0.6M HEDTA in the coreflood experiments. The permeability ratio (final/initial) for Bandera sandstone cores was 2 in the case of GLDA and 1.2 in the case of HEDTA at pH of 4 and 300oF. At high pH HEDTA was the best chelating agent to stimulate different sandstone cores, and at low pH GLDA was the best one. For Berea sandstone cores EDTA at high pH of 11 was the best in increasing the permeability of the core at 300oF. The low pH GLDA based fluid has been especially designed for high temperature oil well stimulation in carbonate and sandstone rock. Extensive studies have proved that GLDA effectively created wormholes in carbonate cores, is gentle to most types of casing including Cr-based tubular, has a high thermal stability and gives no unwanted interactions with carbonate or sandstone formations. These unique properties ensure that it can be safely used under extreme conditions for which the current technologies do not give optimal results. Furthermore, this stimulation fluid contributes to a sustainable future as it based on readily biodegradable GLDA that is made from natural and renewable raw material

Scalable Human-Machine Interaction System for Real-Time Care in the Internet of Health Things

The rise in numbers of individuals with weak immunity around the world and the aging of populations put an ever-growing pressure on healthcare and inevitably increases its cost. This phenomenon leads to larger portions of the population to which quality healthcare is not provided. To fight this trend, technological advancements in the Internet of Health Things aim to integrate smart sensors and devices to continuously monitor and assess the status of patients and older adults from the comfort of their own home at a fraction of the cost. Although solving specific problems each at a time advances the field and takes us a step closer to autonomous home care systems, the solution to these issues needs to consider the much larger picture to unify the approaches and cultivate benefits of many intelligent, but stand-alone, systems. The current work aims to explore the field of Internet of Health Things and its application to remote health monitoring and ambient assisted living for older adults. Picking up from where previous literature left off, this thesis proposes a multi-layered framework that provides a comprehensive solution to continuous healthcare. In particular, the framework was created with modularity, scalability, and expandability as the main priorities; to offer an all-purpose remedy to the problems in hand. To this end, the internal mechanisms of the framework are described in detail and the system is applied to remote health monitoring and ambient assisted living environments by interchanging its components. The implementations presented in this thesis expose the capability of the framework to harvest power of existing intelligent devices. Moreover, the two systems implemented consider multi-modal and natural human-machine interaction techniques that provide the user with the choice of their preferred interaction method. The main advantage of the proposed framework is that it offers an all-in-one solution to providing continuous healthcare without sacrificing the quality of care provided. On the contrary, the solution in this work allows deeper understanding of user's health, personalization, real-time analytics and recommendations, as well as aid for activities of daily living with state of the art technologies

Strengthening of Edge and Corner Columns using Concrete Jackets

Strengthening of columns using concrete jackets depends on friction at the interface between them. So strengthening of edge and corner columns in only one story needs a large cross section area due to the shortage of friction length which leads to architectural issues. This research aims to study strengthening the edge and corner columns using a concrete Jacket in more than one story which increases the friction area between the Jacket and the original column. As a result, the load transferred from original column to the jacket will be increased. Thirteen models were done using ANSYS program to study the effect of various factors on the Jacket capacity such as the number of strengthened floors, the Jacket type (two sides or three sides), and whether there were shear connectors or not. The results showed that in the case of the edge and corner columns, it is preferable to strengthen the column by making a concrete Jacket on at least two or three floors to increase the surface area, which leads to increase the friction and thus increases the capacity of the strengthened column by an acceptable percentage. The results of ANSYS models were compared with the Indian code IS 15988 (2013) and the results were shown differently because the code equations depend on the presence of a full bond between the concrete column and the Jacket, which does not occur, but rather the load is transferred by friction between the Jacket and the original column. Doi: 10.28991/cej-2021-03091716 Full Text: PD

Removing of Formation Damage and Enhancement of Formation Productivity Using Environmentally Friendly Chemicals

Matrix acidizing is used in carbonate formations to create wormholes that connect the formation to the wellbore. Hydrochloric acid, organic acids, or mixtures of these acids are typically used in matrix acidizing treatments of carbonate reservoirs. However, the use of these acids in deep wells has some major drawbacks including high and uncontrolled reaction rate and corrosion to well tubulars, especially those made of chrome-based tubulars (Cr-13 and duplex steel), and these problems become severe at high temperatures. Hydrochloric acid (HCl) and its based fluids have a major drawback in stimulating shallow (low fracture gradient) formations as they may cause face dissolution (formation surface washout) if injected at low rates. The objective of stimulation of sandstone reservoirs is to remove the damage caused to the production zone during drilling or completion operations. Many problems may occur during sandstone acidizing with Hydrochloric/Hydrofluoric acids (HCl/HF) mud acid. Among those problems: decomposition of clays in HCl acids, precipitation of fluosilicates, the presence of carbonate can cause the precipitation of calcium fluorides, silica-gel filming, colloidal silica-gel precipitation, and mixing between various stages of the treatment. To overcome problems associated with strong acids, chelating agents were introduced and used in the field. However, major concerns with most of these chemicals are their limited dissolving power and negative environmental impact. Glutamic acid diacetic acid (GLDA) a newly developed environmentally friendly chelate was examined as stand-alone stimulation fluid in deep oil and gas wells. In this study we used GLDA to stimulate carbonate cores (calcite and dolomite). GLDA was also used to stimulate and remove the damage from different sandstone cores containing different compositions of clay minerals. Carbonate cores (calcite and dolomite) of 6 and 20 in. length and 1.5 in. diameter were used in the coreflood experiments. Coreflood experiments were run at temperatures ranging from 180 to 300oF. Ethylene diamine tetra acetic acid (EDTA), hydroxyl ethylethylene diaminetriacetic acid (HEDTA), and GLDA were used to stimulate and remove the damage from different sandstone cores at high temperatures. X-ray Computed Topography (CT) scans were used to determine the effectiveness of these fluids in stimulation calcite and dolomite cores and removing the damage from sandstone cores. The sandstone cores used in this study contain from 1 to 18 wt percent illite (swellable and migratable clay mineral). GLDA was found to be highly effective in creating wormholes over a wide range of pH (1.7-13) in calcite cores. Increasing temperature enhanced the reaction rate, more calcite was dissolved, and larger wormholes were formed for different pH with smaller volumes of GLDA solutions. GLDA has a prolonged activity and leads to a decreased surface spending resulting in face dissolution and therefore acts deeper in the formation. In addition, GLDA was very effective in creating wormholes in the dolomite core as it is a good chelate for magnesium. Coreflood experiments showed that at high pH values (pH =11) GLDA, HEDTA, and EDTA were almost the same in increasing the permeability of both Berea and Bandera sandstone cores. GLDA, HEDTA, and EDTA were compatible with Bandera sandstone cores which contains 10 wt percent Illite. The weight loss from the core was highest in case of HEDTA and lowest in case of GLDA at pH 11. At low pH values (pH =4) 0.6M GLDA performed better than 0.6M HEDTA in the coreflood experiments. The permeability ratio (final/initial) for Bandera sandstone cores was 2 in the case of GLDA and 1.2 in the case of HEDTA at pH of 4 and 300oF. At high pH HEDTA was the best chelating agent to stimulate different sandstone cores, and at low pH GLDA was the best one. For Berea sandstone cores EDTA at high pH of 11 was the best in increasing the permeability of the core at 300oF. The low pH GLDA based fluid has been especially designed for high temperature oil well stimulation in carbonate and sandstone rock. Extensive studies have proved that GLDA effectively created wormholes in carbonate cores, is gentle to most types of casing including Cr-based tubular, has a high thermal stability and gives no unwanted interactions with carbonate or sandstone formations. These unique properties ensure that it can be safely used under extreme conditions for which the current technologies do not give optimal results. Furthermore, this stimulation fluid contributes to a sustainable future as it based on readily biodegradable GLDA that is made from natural and renewable raw material

A novel optimized conical antenna array structure for back lobe cancellation of uniform concentric circular antenna arrays

In wireless communication systems, the existence of the antenna array back lobe represents a significant source of interference, which causes degradation of the signal-to-interference ratio (SIR), and power loss. In this paper, a novel optimized conical antenna array (O-CONAA) structure is proposed for back lobe cancellation of concentric circular antenna arrays (CCAA). Based on the CAA, It is considered to be made up Of several concentric circular antenna arrays (CCAA) which are placed in the X-Y plane. Firstly a non-optimized CONAA is constructed, by arranging these concentric CAAs with uniform vertical spacing along the Z-axis. Consequently, the CONAA seems to be treated as a combination between uniform CAAs and a linear antenna array (LAA). It has been noted that the CONAA radiation pattern has a back lobe amplitude the same as the main beam amplitude. The O-CONAA structure is suggested as a solution to this problem, which provides back lobe cancellation while maintaining the CONAA pattern characteristics like half power beamwidth (HPBW) side lobe level (SLL). The genetic algorithm(GA) approach is used in the O-CONAA structure to optimize the values of both CONAA inter-element spacing around the perimeter of each circle, and vertical spacing along the Z-axis to generate the desired radiation pattern

A novel optimized conical antenna array structure for back lobe cancellation of uniform concentric circular antenna arrays

In wireless communication systems, the existence of the antenna array back lobe represents a significant source of interference, which causes degradation of the signal-to-interference ratio (SIR), and power loss. In this paper, a novel optimized conical antenna array (O-CONAA) structure is proposed for back lobe cancellation of concentric circular antenna arrays (CCAA). Based on the CAA, It is considered to be made up Of several concentric circular antenna arrays (CCAA) which are placed in the X-Y plane. Firstly a non-optimized CONAA is constructed, by arranging these concentric CAAs with uniform vertical spacing along the Z-axis. Consequently, the CONAA seems to be treated as a combination between uniform CAAs and a linear antenna array (LAA). It has been noted that the CONAA radiation pattern has a back lobe amplitude the same as the main beam amplitude. The O-CONAA structure is suggested as a solution to this problem, which provides back lobe cancellation while maintaining the CONAA pattern characteristics like half power beamwidth (HPBW) side lobe level (SLL). The genetic algorithm(GA) approach is used in the O-CONAA structure to optimize the values of both CONAA inter-element spacing around the perimeter of each circle, and vertical spacing along the Z-axis to generate the desired radiation pattern

Performance Evaluation of Hand-Held Olive Harvesters

The aim of this research was to evaluate three types of commonly used hand-held olive harvesters in small olive farms (pulsed motion double head olive harvester, hook type hand-held olive harvester and pneumatic comb olive harvester) in the Kingdom of Saudi Arabia. The specific objectives were to (a) determine the values of some olive plant parameters including physical-mechanical properties of fruit-stem system, natural frequency of the olive fruit-stem system and suitable shaking stroke), (b) establish and determine the values of the evaluation criteria which included machine productivity, fruit removal percentage, fruit damage, specific consumed energy and olive harvesting cost, (c) determine the quality characteristic for each criterion, (d) assign the evaluating criteria their relative weights, (e ) perform field experiments to assess the performance of the three harvesters and (f) calculate the value of overall evaluation criterion. The study was carried out during the period of 2017-2018. The average values of natural frequency were 30.1, 28.1 and 24.0 Hz for full mature stage, half-ripe and full-ripe fruits, respectively. The estimated values of damping ratio were 0.103, 0.103 and 0.106 for full mature stage, half-ripe and full-ripe fruits respectively. The estimated shaking stroke was about 70 mm. The highest values of machine productivity (88.4 kg.h-1) and fruit removal percentage (98.0%) were found with the pulsed motion double head olive harvester at the speed of 1500 rpm while the lowest value of machine productivity (55.6 kg.h-1) and  fruit removal percentage (62.4%) were found with the hook type olive harvester at the 24 Hz frequency and 70 mm stroke. The highest fruit damage (5.5-6.6) was observed with the pulse motion double head harvester while the lowest fruit damage (2.0-2.5%) was observed with the hook type harvester. The specific consumed energy values ranged from 17.0 to 27.0 W.h.kg-1. The total harvesting costs were 3.62, 3.65 and 3.69 $.h-1 for the pulse motion double head harvester, the hook type harvester and the pneumatic comb harvester, respectively. The results showed that the highest value of overall evaluation criterion (OEC) was 84.9 for the pulsed motion double head olive harvester at speed of 1500 rpm). Also, the values of OEC of the pulsed motion double head olive harvester for the other two speeds (1100 and 1300 rpm) outperformed the other harvesters (at all treatments). The higher OEC of the pulse motion double head olive harvester was due to the low operating costs and increased fruit removal percentage. Based on OEC, the pulsed motion double head olive harvester came first (OEC in the range of 70.2.5-84.9 %), followed by the pneumatic comb olive harvester (OEC in the range of 42.8-70.2 %) and the hook type olive harvester olive harvesters (OEC in the range of 13.9-54.3%)

BER and Capacity/Spectral Efficiency Enhancement of MIMO Systems Using Digital Antenna Arrays Beamforming

Multi-input Multi-output (MIMO) systems are of the most promising ones in the field of wireless communications as they provide high data rates and reduce the bit error rate (BER) using spatial multiplexing (SM) and diversity gain techniques, respectively. The deep review of MIMO systems shows that most of them are based on the utilization of uniform linear antennas (ULA) arrays. For further performance enhancement, a new digital array beamforming technique for linear antenna arrays optimization is introduced for both single-user and multi-user MIMO systems to achieve maximum gain. In our proposed technique, the antenna arrays are implemented for a higher gain by adjusting the feeding and the distance between the antenna elements. The modified mathematical model for our proposed digital array beamforming MIMO system has been derived and merged to the current linear detection techniques such as Maximum Likelihood (ML), Zero Forcing (ZF), and Minimum Mean Square Error (MMSE). The simulation results demonstrated the superiority of our proposed technique over the traditional MIMO systems in terms of BER and spectral efficiency (SE)

BER Performance Enhancement of MIMO Systems Using Hybrid Detection Techniques Based on Sphere Decoding

MIMO system is used in new communication systems to improve the bit error rate (BER), capacity, and the co-channel interference. In this paper, new hybrid detection techniques based on a combination between the sphere decoder (SD) and linear/non-linear detection techniques such as zero forcing (ZF), minimum mean square error (MMSE), Vertical Bell Lab Layered Space Time (V-BLAST), and lattice reduction are introduced. These hybrid techniques are intended to improve the BER performance of MIMO system. The proposed techniques are mainly based on dividing the received signal matrix into two equal size halves. The first half of the received symbols is detected using the selected linear or non-linear detector and the second half is detected using SD as the first scenario. For the second scenario, the first half of the received symbols is detected using SD and the second half is detected using the selected linear or non-linear detector. Several simulations are carried out to verify the efficiency of the proposed techniques. The simulations results show that the proposed techniques provide better performance than the traditional ones

Treatment of Swelling Soil Using Crushed Glass Wastes and Lime

This research aims to improve the engineering properties of expansive soil by using locally low-cost materials such as crushed glass wastes and lime. The studied expansive soil is considered unsuitable soil for civil engineering projects such as roads and buildings, as it was classified according to the AASHTO classification A-7-6. This soil was treated only with different ratios of crushed glass wastes (0%, 5%, 10%, 15%, and 20% by weight of dry soil), as well as the soil was treated only with different ratios of lime (0%, 2%, 4%, 6%, and 8% by weight of dry soil). Experiments of Atterberg limits, standard Procter, direct shear, free swell, swelling pressure, and both un-soaked and soaked California Bearing Ratio tests were carried out on the untreated and treated soil. The results showed that by increasing added percentage of crushed glass wastes and lime separately, the consistency properties (Atterberg limits), the shear strength parameters (direct shear test), free swell, swelling pressure, and both un-soaked and soaked California Bearing Ratio of the studied expansive soil were improved; except for compaction characteristics, by adding crushed glass wastes the M.D.D was increased and O.M.C was decreased while by adding lime, the M.D.D was decreased and O.M.C was increased. This helps to make use of low-cost local materials, clean the environment of glass wastes, and recycle these wastes so that they can be used on an environmental, economic, and engineering level. This aligns with Egypt's Vision 2030 sustainable development approach in both the environmental and economic dimensions