Smart Water Solution Research Articles

Experimental investigation of carbamide-assisted smart water flooding for enhancing heavy oil recovery from carbonate reservoirs

This study explores the impact of carbamide at different concentrations on smart water flooding into carbonate reservoirs. The aim is to find out how the presence of carbamide can influence the mechanisms of smart water flooding at rock/brine and oil/brine interfaces. The results revealed that interfacial tension (IFT) reduces as the carbamide concentration increases in the brine. Indeed, the carbamide decomposes at elevated temperatures, and in-situ surface active agents are formed at the oil/brine interface, reducing IFT values. Further, while the dilution of seawater (SW) is unable to change the oil-wet wettability, the carbamide can make the carbonate surface more water-wet by elevating its concentration. Additionally, the corresponding mechanisms of this wettability alteration would be the formation of in-situ surface active agents, electrostatic interactions, and hydrogen bond formation at the rock/brine interface. Among K+, Mg2+, and SO42−, adjusting the concentration of sulfate ions in SW leads to greater IFT reduction in the presence of carbamide. In addition, the contact angle is further reduced as K+ concentration is doubled in the solution; however, this reduction is not significant as compared to Mg2+ and SO42−. Also, ten-times diluted seawater (10dsw) produced more micro-dispersions in the oil phase. Nevertheless, the presence of carbamide in 10dws had a negative impact on the micro-dispersion formation, which is one of the driving mechanisms of smart water flooding. At a lower carbamide concentration (1000 ppm), more carboxylic acids and ketones were observed in the brines due to the partitioning and dissociation of naphthenic acids. On the contrary, as carbamide concentration increased to 10000 ppm, amounts of carboxylic acids declined due to the production of in-situ surface active agents at the oil/brine interface. Bottle test experiments indicated that water-in-oil emulsions were generated in the presence of carbamide. The mean water droplet size grew as carbamide concentration rose to 25000 ppm; nonetheless, further increase in the carbamide concentration resulted in mean droplet size reduction. Calcite-coated micromodel flooding illustrated that oil recovery of 21.6, 24, and 27.2 % was found at carbamide concentrations of 1000, 10000, and 100000 ppm. Furthermore, a three-time increase in SO42− concentration at 10000 ppm of carbamide offered a better performance in boosting oil recovery than tuning K+ and Mg2+ concentrations in carbamide/SW solutions. The findings of this study underscore the promising prospects of leveraging carbamide to enhance the efficacy of smart water solutions in carbonate reservoirs, particularly regarding IFT modification, wettability alteration, and oil recovery enhancement.

Building a Smart Water City: IoT Smart Water Technologies, Applications, and Future Directions

Water is an essential service for the sustainable development and economic competitiveness of any country. The global water demand has increased substantially due to economic development, climate change, and rising population. The Internet of Things (IoT) and Information and Communication Technologies (ICT) can help conserve available water resources. Smart cities apply IoT to boost the performance and efficiency of urban facilities. Smart cities are towns created to use IoT and ICT (innovative technologies) such as smart water applications. Several studies on smart water technology have been conducted, but there is a need to review current research that leverages the IoT as a communication technology to design effective smart water applications. This review paper is aimed at presenting evidence on the current design of smart water applications. The study also covers publication statistics to increase collaboration between stakeholders. Findings show that various technologies such as microcontrollers, embedded programming languages, sensors, communication modules, and protocols are used by researchers to accomplish their aim of designing IoT-based smart water solutions. None of the publications employed the 5G mobile networks as a communication module for their smart water application development. Findings further show that the integration of 3D printing and solar energy into IoT-based smart water applications is revolutionary and can increase the sustainability of the systems. Future directions required to ensure that developed smart water applications are widely adopted to help conserve and manage water resources are suggested.

Development of sulfate-based smart water for improving the oil recovery from the calcite formation: New insights from molecular simulation

Wettability plays a huge role in the process of oil displacements, particularly in highly complex oil-wet carbonate reservoirs. Recently, sulfate ions were witnessed to have a great potency to alter the wetting state of calcite. Though the role of sulfate ion studied extensively, still the mechanism of their wettability modification is yet to be fully understood. It is expected due to the complex surface chemistry of rock in the presence of monovalent and divalent ions. In this study, we constructed a rock-oil-brine model at a molecular level and run the simulation on the wettability dynamics with various ions. The most abundant surface structure of calcite {1014}, was considered for this atomistic simulations. The model oil consisted of n-heptane and 10% octanoate ion as a polar component and sulfate-based salts were used as smart water. Two distinct hydration layers were found on the calcite surface. The contact angle measurements were made to find the effectiveness of smart water solutions in altering the wettability of the surface. Monovalent cations were observed to form a strong electric-double-layer while the divalent cations were preferred to get distributed in the bulk; most of them were attached to polar oil ions removing them from the calcite surface thus changing the wettability.

Smart Water Solutions for the Operation and Management of a Water Supply System in Aracatuba, Brazil

Because of population growth, rapid urbanization, and climate change, many water supply utilities globally struggle to provide water that is safe to drink. A particular problem is the aging of the water supply facilities, which is exacerbated by their inefficient operation and maintenance (O&M). For this reason, many water utilities have recently been actively adopting intelligent and integrated water supply O&M solutions that utilize information and communication technology, the Internet of Things, big data, and artificial intelligence to solve water supply system problems. In this study, smart water solutions (GSWaterS) were implemented to enhance the efficiency of the water supply system in the city of Aracatuba, Brazil. They were used to monitor and analyze the operating conditions of the water supply system in real time, thus allowing for the effective management of water supply assets. GSWaterS also supports the design and optimization of district metered areas, the reduction and management of water losses, real-time water network analysis, and big data analysis using artificial intelligence. Economic analysis revealed that GSWaterS produces various direct and indirect benefits for the water supply system.

Experimental Core Flooding Investigation of New ZnO-γAl2O3 Nanocomposites for Enhanced Oil Recovery in Carbonate Reservoirs.

Generally, crude oil production in mature oil reservoirs is difficult. In this regard, some nanoparticles have been used to upgrade injected water into oil reservoirs. These nanoparticles can be used in a variety of injectable waters, including smart water (SMW) with special salinity. This study aims to evaluate the performance of the injection of SMW with ZnO-γAl2O3 nanoparticles in enhanced oil recovery (EOR). The performance of SMW with ZnO-γAl2O3 nanoparticles in regard to contact angle (CA), interfacial tension (IFT) reduction, and oil production with core flooding tests was investigated. The newly prepared ZnO-γAl2O3 structure was characterized by energy dispersive X-ray (EDX), Fourier transform infrared (FT-IR) spectroscopy, transmission electron microscopy (TEM), scanning electron microscopy (SEM), and X-ray diffraction (XRD) analyses in this research. The effects of different concentrations of nanofluids on zeta potential (ZP) and conductivity were investigated. The ZP test confirmed the results of the stability tests of the developed nanofluids in water-based solutions. After the introduction of ZnO-γAl2O3 nanoparticles into the formation of brine and SMW solutions, oil-water (O/W) IFT was reduced. Based on the results, the IFT decreased more when nanoparticles and ions were present in the system. The results of the present study showed that at the concentration of SW+300 ppm ZnO-γAl2O3, the IFT value reached 11 mN/m from 27.24 mN/m. The results of the CA tests showed that improving the capabilities of salt water in the presence of nanoparticles has resulted in a very effective reduction. Also, in this regard, very hydrophilic wettability was achieved using SMW with stable nanoparticles. Moreover, the results of the present study showed that at the concentration of SMW+300 ppm ZnO-γAl2O3 nanoparticles, the CA value reached 31 from 161°. In the end, the solution of SW+300 ppm ZnO-γAl2O3 improved the OR by 15 and 24%. This research indicated that it is possible to develop and implement different nanoparticles by combining SMW to manage reservoir rock wettability and maximize OR from carbonate reservoirs. Thus, this combination as an effective agent could significantly increase reservoir sweep efficiency. Thus, as a result, using the established hybrid technique has distinct advantages over using SMW flooding alone.

Environmental application of a cost-effective smartphone-based method for COD analysis: Applicability in the electrochemical treatment of real wastewater

This study aims to develop a cheap method for the evaluation of quality of water or the assessment of the treatment of water by chemical oxygen demand (COD) measurements throughout the use of the HSV color model in digital devices. A free application installed on a smartphone was used for analyzing the images in which the colors were acquired before to be quantified. The proposed method was also validated by the standard and spectrophotometric methods, demonstrating that no significant statistical differences were attained (average accuracy of 97 %). With these results, the utilization of this smartphone-based method for COD analysis was used/evaluated, for first time, by treating electrochemically a real water matrix with substantial organic and salts content using BDD and Pt/Ti anodes. Aiming to understand the performance of both anodes, bulk experiments were performed under real pH by applying current densities (j) of 15, 30, and 60 mA cm−2. COD abatement results (which were achieved with this novel smart water security solution) clearly showed that different organic matter removal efficiencies were achieved, depending on the electrocatalytic material used as well as the applied current density (42 %, 45 %, and 85 % for Ti/Pt while 93 %, 97 % and total degradation for BDD by applying 15, 30, and 60 mA cm−2, respectively). However, when the persulfate-mediated oxidation approach was used, with the addition of 2 or 4 g Na2SO4 L−1, COD removal efficiencies were enhanced, obtaining total degradation with 4 g Na2SO4 L−1 and by applying 15 mA cm−2. Finally, this smartphone imaging-based method provides a simple and rapid method for the evaluation of COD during the use of electrochemical remediation technology, developing and decentralizing analytics technologies for smart water solutions which play a key role in achieving the Sustainable Development Goal 6 (SDG6).

Increasing Reservoir Recovery Efficiency through Laboratory-Proven Hybrid Smart Water-Assisted Foam (SWAF) Flooding in Carbonate Reservoirs

This contribution introduces a new hybrid enhanced oil recovery (EOR) method which combines smart water-assisted foam (SWAF) flooding, known as the SWAF process. The concept of applying SWAF flooding in carbonate reservoirs is a novel approach previously unexplored in the literature. The synergy effect of the SWAF technique has the potential to mitigate a number of limitations related to individual (i.e., conventional water injection and foam flooding) methods encountered in carbonates. In general, carbonate rocks are characterized by a mixed-wet to oil-wet wettability state, which contributes to poor oil recovery. Hence, the smart water solution has been designed to produce a dual-improvement effect of altering carbonate rock wettability towards more water-wet, which preconditions the reservoir and augments the stability of the foam lamellae, which has for some conditions more favorable relative permeability behavior. Then the smart water solution is combined with surfactant (surfactant aqueous solution or SAS) and gas injection produces a synergy effect, which leads to more wettability alteration, and interfacial tension (IFT) reduction, and thus improves the oil recovery. Accordingly, to determine the optimal conditions of smart water solution with an optimal SAS, we conducted a series of experimental laboratory studies. The experimental design is divided into three main steps. At first, the screening process is required so that the candidates can be narrowed down for our designed smart water using the contact angle tests that employ calcite plate (i.e., Indiana limestone or ILS) as the first filter. Following this, the optimum smart water solutions candidates are blended with different types of cationic and anionic surfactants to create optimum SAS formulations. Subsequently, a second screening process is performed with the aim to narrow down the SAS candidates with varying types of gases (i.e., carbon dioxide, CO2 and nitrogen, N2) via the aqueous stability test (AST), foamability test (FT), and foam stability test (FST). We employed the state-of-the-art R5 parameter tests for rapid and accurate results in place of the conventional foam half-life method. The most effective combination of SAS and gas candidates are endorsed for the core-flooding experiments. In this work, two types of crude oils (Type A and B) with different total acid and base numbers (TAN and TBN). Results showed that the greatest wettability changes occurred for SW (MgCl2) solution at 3500 (ppm) for both crude oil types. This demonstrates the efficacy of our designed SW in the wettability alteration of carbonates, which is also supported by the zeta-potential measurements. The concentrations of both SW (MgCl2) and CTAB-based surfactants considerably affect the stability of the SAS (i.e., up to 90% foam stability). However when in the presence of crude oil, for the same SAS solution, the foam stability is reduced from 90% to 80%, which indicates the negative effect of crude oil on foam stability. Moreover, the core floods results showed that the MgCl2-foam injection mixture (MgCl2 + CTAB + AOS + N2) provided the highest residual oil recovery factor of SWAF process of 92% cumulative recovery of original oil in core (OIIC). This showcases the effectiveness of our proposed SWAF technique in oil recovery from carbonate reservoirs. Additionally, changing the large slug of 5 PVs to a small slug of 2 PVs of smart water solution was more effective in producing higher OIIC recovery and in reducing the fluid circulation costs (i.e., thereby, lowering CO2 footprint), making the SWAF process environmentally benign. Thus, it is expected that under optimum conditions (SW solution and SAS), the novel SWAF process can be a potentially successful hybrid EOR method for carbonate reservoirs, having both economic and environmental benefits.

Achieving Electrochemical-Sustainable-Based Solutions for Monitoring and Treating Hydroxychloroquine in Real Water Matrix

Hydroxychloroquine (HCQ) has been extensively consumed due to the Coronavirus (COVID-19) pandemic. Therefore, it is increasingly found in different water matrices. For this reason, the concentration of HCQ in water should be monitored and the treatment of contaminated water matrices with HCQ is a key issue to overcome immediately. Thus, in this study, the development of technologies and smart water solutions to reach the Sustainable Development Goal 6 (SDG6) is the main objective. To do that, the integration of electrochemical technologies for their environmental application on HCQ detection, quantification and degradation was performed. Firstly, an electrochemical cork-graphite sensor was prepared to identify/quantify HCQ in river water matrices by differential pulse voltammetric (DPV) method. Subsequently, an HCQ-polluted river water sample was electrochemically treated with BDD electrode by applying 15, 30 and 45 mA cm−2. The HCQ decay and organic matter removal was monitored by DPV with composite sensor and chemical oxygen demand (COD) measurements, respectively. Results clearly confirmed that, on the one hand, the cork-graphite sensor exhibited good current response to quantify of HCQ in the river water matrix, with limit of detection and quantification of 1.46 mg L−1 (≈3.36 µM) and 4.42 mg L−1 (≈10.19 µM), respectively. On the other hand, the electrochemical oxidation (EO) efficiently removed HCQ from real river water sample using BDD electrodes. Complete HCQ removal was achieved at all applied current densities; whereas in terms of COD, significant removals (68%, 71% and 84% at 15, 30 and 45 mA cm−2, respectively) were achieved. Based on the achieved results, the offline integration of electrochemical SDG6 technologies in order to monitor and remove HCQ is an efficient and effective strategy.

An experimental study of the combination of smart water and silica nanoparticles to improve the recovery of asphaltenic oil from carbonate reservoirs

Within recent decades, smart water (SW) injection has become an attractive approach to improve oil recovery from conventional oil reservoirs. However, less attention has been devoted to the application of this method to asphaltenic oil reservoirs. This study aims to evaluate the performance of the injection of SW + silica nanoparticles (SNPs) in improving oil recovery from such reservoirs. To this end, an extended series of measurements were conducted, including of oil-water interfacial tension (IFT), wettability, emulsion formation/stability, and core flooding tests. After the introduction of SNPs to formation brine (FB) and SW solutions, oil-water IFT was reduced by 17.5% and 52.5% respectively compared to their corresponding initial values. In addition, the SW + SNP solution could improve the wettability of the rock surface compared to FB + SNPs. Interestingly, we found that, due to its high asphaltene content, the crude oil used forms sludge in contact with FB, which will impose serious operational problems and production costs associated with the system. However, we observe that the presence of SNPs restrains sludge formation by breaking down asphaltene molecules as well as destabilizing oil-water emulsions. This is demonstrated by several centrifuge tests conducted to evaluate emulsion stability in the presence of FB + SNP and SW + SNP solutions. SARA analyses were also performed on the oil produced from core plugs after the injection of SW and SW + SNPs to better understand the role of SNPs in the deposition of complex structures like asphaltenes and resins groups in crude oil. • The performance of smart water + silica nanoparticles in IFT reduction and wettability alteration. • Crude oil-water emulsion stability in the presence of silica nanoparticles. • Application of SARA analyses to study asphaltene precipitation during core flooding tests. • Micrograph studies for emulsion stability in the presence of various aqueous solutions.

Taking water efficiency to the next level: digital tools to reduce non-revenue water

Abstract Efficiency optimization of urban water systems is a growing concern for water utilities worldwide. This case study aimed at evaluating the impact of using cloud-based tools on the reduction of both real (real-time network monitoring) and apparent water losses (integrated customer meters management) in two water utilities. The incorporation of smart water solutions with a methodology for the management and operation of the systems allowed us to diagnose, prioritize areas and define actions to improve efficiency. Using a real-time monitoring tool allowed us to categorize bursts and to evaluate their impact on water loss volumes and to identify operational inefficiencies regarding detection and repair times, particularly in small and medium bursts. Additionally, the implementation of an integrated customer meters management tool allowed for an optimized meter management reducing apparent losses by estimating metering errors more accurately, enabling the water utilities to replace meters based on specific lifespan. Digitalization, through the implementation of optimized algorithms and early warning systems, allowed the analysis of data in a methodical and prompt manner resulting in non-revenue water reduction up to 8% in 3 years while improving the digital organization of data and its quality (reliability and accuracy), interdepartmental organization and communication, capacity building and utilities’ image among stakeholders.

Emerging applications of TiO2/SiO2/poly(acrylamide) nanocomposites within the engineered water EOR in carbonate reservoirs

In this study, TiO2/SiO2/poly(acrylamide) nanocomposites (NCs) as a newly-developed-nano enhanced oil recovery (EOR) agent is proposed using a simple, green and economic method from the extract of pomegranate seeds. The ultraviolet–visible spectroscopy (UV–Vis), X-ray diffraction (XRD), Fourier-transform infrared spectroscopy (FT-IR), scanning electron microscopy (FE-SEM), transmission electron microscopy (TEM) and energy-dispersive X-ray spectroscopy (EDS) are applied to analyze the characterization of NCs. Nano-smart solutions are prepared from the dispersion of NCs within the smart water at three different concentrations (500, 1000 and 1500 ppm). The used smart water solutions are formulated from mixing the single and binary systems of the monovalent and divalent salts (NaCl, KCl, MgCl2, CaCl2, Na2SO4, MgSO4, K2SO4 and CaSO4) at different concentrations of 2500, 5000 and 10,000 ppm within the distilled water. In order to identify the effect of the prepared NCs in smart EOR applications, the interfacial tension (IFT) of crude-oil/smart-water and crude-oil/smart-nanofluid systems is measured using the pendant drop technique, the wettability behavior of carbonate rock is studied using the contact angle (CA) measurement, and recovery efficiency is determined by preforming the coreflooding test for eight core plugs. According to the obtained experimental results of IFT and CA, KCl-5000, K2SO4-5000, CaSO4 + CaCl2 (5000 + 5000) and K2SO4+ CaCL2 (2500 + 2500) are selected as the optimal smart solutions. Furthermore, the performance of the selected smart water solutions is influenced by 65% in IFT reduction, 32% in wettability alteration and 10.5% in oil recovery when the prepared NCs is added to the solutions. Nano-OSS3-5000 smart-nanofluid developed from mixing 1500 ppm of TiO2/SiO2/poly(acrylamide) NCs with 5000 ppm of CaSO4 and CaCl2 ions demonstrated the highest performance in increasing oil recovery from 36.0 to 46.53% original oil in place (OOIP).

Mechanistic study to investigate the injection of surfactant assisted smart water in carbonate rocks for enhanced oil recovery: An experimental approach

More than half of the world's discovered oil is held in carbonate reservoirs, most of which are naturally oil-wet fractured reservoirs. Oil Recovery efficiency can be improved noticeably if the rock wettability is changed from an oil-wet to a water-wet state. However, what factors control the wettability alteration are not clearly specified. In this study, a comprehensive mechanistic study is performed using different experimental tools to investigate the effects of active ions, non-active ions, CTAB, and different combinations of ions and CTAB on the sample rock's wettability. The results indicate that using CTAB and a smart water solution, in which the sodium and chloride ions are eliminated and the concentration of sulfate ions is increased, (SW-0NaCl-4SO42− + 1CTAB) reduced the contact angle to 43.58°. The zeta potential value of the oil-wet calcite powder increased from −61.12 to −7.6 mV after treatment with SW-0NaCl-4SO42− + 1CTAB. Moreover, the mean roughness value of oil-wet calcite powder increased from 5.02 to 25.89 nm after treatment with SW-0NaCl-4SO42− + 1CTAB. In fact, sulfate ions are capable of removing the strongly adsorbed carboxylic groups from the surface and changing the wettability of the calcite surface to a more water-wet state. Also, the cationic surfactant monomers tend to ionically react with carboxylic groups and separate them from the calcite surface. Moreover, the removal of sodium and chloride ions also leads to significant changes in the wettability. The imbibition results showed that the change of wettability from an oil-wet to a more water-wet state results in a critical increase in oil recovery efficiency during imbibition of distilled water into the calcite rock slice. High oil recovery efficiency can be obtained by optimizing the smart water solution composition and using a proper concentration of surfactant.

Smart Water Solution for Monitoring of Water Usage Based on Weather Condition

Smart Water Solution for Monitoring of Water Usage Based on Weather Condition

Direct insights into the micro and macro scale mechanisms of symbiotic effect of SO42−, Mg2+, and Ca2+ ions concentration for smart waterflooding in the carbonated coated micromodel system

Up to now, a large number of studies revealed that smart waterflooding is a cost-effective method by considering the effect of potential determining ions (PDI) on enhanced oil recovery (EOR) in the carbonated reservoir. Current research studied the symbiotic effect of different ions concentration (SO42−, Mg2+, and Ca2+) template in smart water with a constant salinity (40,572 ppm) to justify effective mechanisms at macro and micro scale in a coated carbonated micromodel system. A set of experimental tests such as X-ray diffraction (XRD), compatibility, zeta potential, interfacial tension (IFT), and contact angle (CA) were conducted to determine the type of rock and examine the effect of ions on oil/brines/rock interaction, combined with carbonated coated micromodel flooding tests to determine the optimum smart water solution. Zeta potential tests revealed that the excess amount of SO42− and Mg2+ changed the surface charge into highly negative and positive ones, respectively. Two times excess amount of SO42− (SW2S) had a key role to alter the wettability by measuring CA from 40° to 147°, however, no considerable relation among oil/brines interaction was observed for the IFT reduction. Findings corroborated that Ca2+ and SO42− were the major components for desorbing the carboxylic group from the calcite surface at room temperature. The carbonated coated micromodel flooding results showed that SW2S led to higher ultimate oil recovery (~38%), reconfirmed that wettability alteration was the main mechanism and resulted in better pore-scale performance by less amount of residual oils and discontinuities around the carbonated coated grains.

Sustaining sulfate ions throughout smart water flooding by nanoparticle based scale inhibitors

Smart water flooding (SWF) has been successfully implanted in many fields around the world for the past decades. In this approach, smart water is injected into the reservoir to change the surface characteristics of rocks and improve the oil recovery. However, the presence of sulfate ions in the smart water and their interactions with the cations dissolved in the formation water (FW) may generate what is called scale. There have been several approaches proposed so far to inhibit the scale formations under different conditions but limited success has been reported to the application of these methods once tested under the reservoir conditions. In this paper, a nanomaterial based approach is proposed to inhibit the scale formation during SWF. Nano Glass Flakes (NGFs) and nano silica were considered as two effective nanomaterials in this study and a series of measurements were made to ensure that the scale formation can be inhibited under different temperature and salinity conditions. The results obtained indicates that if the nanoparticles can be properly dispersed in the smart water solution, the likelihood of the scale formation can be significantly decreased and the conductivity can be increased to 0.69 and 0.65 mS/cm for NGFs and nano silica solutions at 50 °C. It appears that NGFs provide a far better performance as temperature rises while nano silica loses its performance. It is also found that the nanoparticles perform better in a high saline water and can be an effective choice for SWF in the concentration of 0.05 wt%. It is also noted that the conductivity improvement made by NGFs in a high salinity water is 0.9 mS/cm while that for water with a low salinity conductivity is 0.23 mS/cm. Given the fact that the nanoparticles used has huge negative surface charge, reduction of the scale formation might be linked to the cations adsorption in the solution but may need further studies.

Transformation of the water system of the Education City in Doha into a smart water system

This paper presents the transformation of the water system of the Education City in Doha (Qatar) into a smart water system. This city covers an area of 14 km2 and includes 80 buildings. The water system provides drinking, irrigation and fire protection services. It suffers from the use of fragmented management systems and from a lack of real-time monitoring, which result in a deterioration of efficiency of the water system and users’ information The paper describes the water system and then the architecture of the smart water solution and its use for leak detection, water quality control and operation safety.

Integrating building and urban semantics to empower smart water solutions

Current urban water research involves intelligent sensing, systems integration, proactive users and data-driven management through advanced analytics. The convergence of building information modeling with the smart water field provides an opportunity to transcend existing operational barriers. Such research would pave the way for demand-side management, active consumers, and demand-optimized networks, through interoperability and a system of systems approach. This paper presents a semantic knowledge management service and domain ontology which support a novel cloud-edge solution, by unifying domestic socio-technical water systems with clean and waste networks at an urban scale, to deliver value-added services for consumers and network operators. The web service integrates state of the art sensing, data analytics and middleware components. We propose an ontology for the domain which describes smart homes, smart metering, telemetry, and geographic information systems, alongside social concepts. This integrates previously isolated systems as well as supply and demand-side interventions, to improve system performance. A use case of demand-optimized management is introduced, and smart home application interoperability is demonstrated, before the performance of the semantic web service is presented and compared to alternatives. Our findings suggest that semantic web technologies and IoT can merge to bring together large data models with dynamic data streams, to support powerful applications in the operational phase of built environment systems.

Effects of water soluble ions on interfacial tension (IFT) between oil and brine in smart and carbonated smart water injection process in oil reservoirs

Water injection is one of the most popular oil recovery methods in oil industry. Investigations have been carried out to find a more effective oil recovery fluid since the first practices of water injection and the idea of low-salinity water or ‘smart water’ was subsequently introduced. The active ions in a smart water solution can significantly decrease the interfacial tension between oil and water in the reservoir; it also has the ability to change the reservoir rock wettability that in return can increase the recovery factor. Also, the carbonated brine injection causes the trapped oil to lose viscosity and increase its mobility.The current study is about smart water and carbonated smart water injection and sets out to investigate the effects of soluble ions on reducing the interfacial tension (IFT) between oil and water and then increasing the oil recovery factor. To achieve this purpose, eleven slats were dissolved in both formation and distilled water. The IFT was then measured by pendant drop method and the results are discussed. Furthermore, the effects of temperature and pressure on IFT are also investigated.We have obtained the optimum salt and concentration of salt for reducing the IFT and, on the other hand, we have investigated the effects of dissolved CO2 in ionic solution on IFT at different conditions. Finally, we have characterized the optimum conditions for the effects of water soluble ions on IFT between oil and brine in smart and carbonated smart water injection in a typical oil reservoir.