Showing papers on "Brine published in 2006"

Accelerated mass transfer of CO2 in reservoir brine due to density-driven natural convection at high pressures and elevated temperatures

Abstract: In this paper, the mass transfer of CO2 into a reservoir brine sample is studied experimentally at high pressures and elevated temperatures. The equilibrium concentration of CO2 in the reservoir brine and the density of CO2-saturated brine are measured by saturating the brine with CO2. The mass-transfer rate of CO2 into the brine is determined by monitoring the pressure decay inside a closed, visual, high-pressure PVT cell. It is found that the density of the brine with dissolved CO2 increases linearly with CO2 concentration. As CO2 gradually dissolves into the brine by molecular diffusion, a concentration-induced density gradient is generated near the CO2−brine interface. Under the influence of gravity, this concentration-induced density gradient causes natural convection, which accelerates the mass-transfer rate of CO2 into the brine. The modified diffusion equation with an effective diffusivity is applied to model the mass-transfer process. It is found that the determined effective diffusivities of CO2...

The effect of sea‐ice growth on air–sea CO2 flux in a tank experiment

Abstract: In order to clarify the CO 2 exchange between the seawater and the overlying air during the sea-ice formation, we have carried out tank experiments in a low-temperature room. CO 2 concentration above the sea-ice began to increase since the beginning of the sea-ice formation, and increased at larger rates with time and the decrease in air temperature. This increase of CO 2 concentration in air was mainly caused by the increase in dissolved inorganic carbon concentration in the brine of the upper part of sea-ice, changes in CO 2 solubility and dissociation constants of carbonic acid. The CO 2 flux increased logarithmically with time, and reached a level of 2 × 10 −4 to 5 × 10 −4 g-C m −2 hr −1 at 50 mm ice thickness. We found that the CO 2 flux was correlated well with the salinity and negatively with the volume of the brine in the upper part of the sea-ice. These suggested the larger role of the difference in partial pressure of CO 2 between brine and air as compared to that of competitive change in the brine volume. Present results suggest the necessity to examine the CO 2 exchange between the seawater and air in seasonal sea-ice areas. DOI: 10.1111/j.1600-0889.2006.00204.x

Treatment of brines for deep well injection

Abstract: A process for conditioning of wastewater treatment brines for deep well injection during recovery of heavy hydrocarbon oils in situ. High pressure steam is used to mobilize oil, which is recovered in a mixture of oil and produced water. The produced water is pre-treated by removing residual oil. The remaining water is acidified and steam stripped to remove non-hydroxide alkalinity and non-condensable gases, and is then fed to a crystallizing evaporator, where it is evaporated from a circulating brine slurry to produce (1) a distillate stream having a trace amount of residual solutes, and (2) evaporator blowdown stream containing, as dissolved or suspended solids, substantially all of the solutes from the produced water feed. The distillate stream is used as boiler feedwater, either directly or after polishing. The evaporator blowdown is conditioned to remove substantially all suspended solids and to produce a clear brine solution for deep well injection.

Dynamics and storage of brine in mid‐ocean ridge hydrothermal systems

Abstract: [1] Mid-ocean ridge hydrothermal systems are known to vent fluids with salinities substantially different from seawater as a result of phase separation and segregation of the resulting vapor and brine phases. Time series of vent temperature and salinity (chlorinity) show that some black-smoker vent fields such as the Main Endeavour Field on the Juan de Fuca Ridge have vented fluids with salinities well below seawater for over a decade, which raises important questions concerning the fate of brines in these systems. One widely accepted model is that high-density brines formed by supercritical phase separation sink to the base of hydrothermal systems, leading to the development of a two-layer system in which a recirculating brine layer underlies a single-pass seawater cell. We first present theoretical arguments to constrain the dynamics of such a deep brine layer in a system still undergoing phase separation, and we conclude that if brines are stored in a basal layer, they are unlikely to convect because they will be stably stratified. One consequence of this result is that the brine layer beneath black smoker systems has to be thin (<10 m) to match the high heat fluxes. However, estimates of the rate at which brines are accumulating in the crust below the main field on the Endeavour segment of the Juan de Fuca Ridge suggest that the brine layer is likely at least 100 m thick. To resolve this apparent paradox, we propose an alternative model. We argue that interfacial tensions between fluid and solid phases will likely favor the segregation of vapor into the main fractures and brine into the smaller fissures and backwaters. This allows the vapor to flow efficiently through the system and transport large heat fluxes while most of the porosity in the lower part of the system fills with brines. It is generally believed that the pressure gradients in mid-ocean ridge hydrothermal systems are close to cold hydrostatic. At the high temperatures and pressures characteristic of the deeper parts of these systems, brines with salinities as high as 20 wt % NaCl have densities around 800–900 kg m−3 and will be buoyant in a cold-hydrostatic system. Rather than sinking to the base of the system, it is possible that brines produced by supercritical phase separation rise slowly until they reach a level of neutral buoyancy as they cool or enter high-permeability regions in which the pressure gradients decrease.

Air Conditioning System for Communication Equipment and Controlling Method Thereof

Abstract: An air conditioning system for communication equipment includes an indoor module placed inside a base station and an outdoor module placed outside the base station. The indoor module has a first indoor heat exchanger installed on a brine pipe and having a heat exchange tube, an expansion valve installed on a refrigerant pipe, a second indoor heat exchanger having a heat exchange tube to which the refrigerant pipe is connected, a compressor for compressing refrigerant, and an indoor blower. The outdoor module has a brine pump installed on the brine pipe, a first outdoor heat exchanger having a heat exchange tube to which the brine pipe extending from the brine pump and the first indoor heat exchanger is connected, a second outdoor heat exchanger having a heat exchange tube to which the refrigerant pipe, extending from the compressor and the expansion valve, is connected, and an outdoor blower.

Three-phase equilibrium and partitioning calculations for CO2 sequestration in saline aquifers

Abstract: [1] We show how the use of appropriate variables results in a flash calculation that uses only equilibrium constraints; it is thus not necessary to solve the mass balance equations self-consistently with the equilibrium equations. We use this implicit material balance in flash calculation. We show its advantages over the current approach that uses an explicit material balance. For the flash calculation for CO2 storage in brine aquifers, use of appropriate variables also allows us to find the dew, bubble, and precipitation points where the liquid, vapor, and solid salt phases, respectively, emerge. Our calculation includes the water content of the vapor phase, which arises from evaporation of the brine. Evaporation leads to increased brine salinity, which results in a large reduction in CO2 solubility in the salting-out effect, and eventually in precipitation of solid salt and ultimately the disappearance of the liquid phase. The flash calculation also relies on our derivation of fugacities for H2O and CO2 in both the brine and the vapor phase.

Statistical Associating Fluid Theory Coupled with Restrictive Primitive Model Extended to Bivalent Ions. SAFT2: 2. Brine/Seawater Properties Predicted

Abstract: Statistical associating fluid theory coupled with restricted primitive model (SAFT2) represents the properties of aqueous multiple-salt solutions, such as brine/seawater. The osmotic coefficients, densities, and vapor pressures are predicted without any additional parameters using the salt hydrated diameters obtained for single-salt solutions. For a given ion composition of brine, the predicted vapor pressure, osmotic coefficient, activity of water, and density are found to agree with the experimental data.

Investigation of Carbon Sequestration via Induced Calcite Formation in Natural Gas Well Brine

Abstract: The permanent storage of carbon in mineral form using natural brines found in geologic formations is at the forefront of carbon sequestration research. A complex chemistry describes the ultimate fixation of carbon in stable minerals, such as calcite. However, the parameters that govern carbonate formation are not well understood. Accordingly, the purpose of this study is to induce and characterize calcite formation by reacting natural gas brine with CO2. Brine pH has a significant effect on this conversion and can thus be adjusted to induce calcite precipitation using a laboratory scale reactor operated at temperatures of 75 and 150 °C and pressures of 600 and 1500 psi. Initial pH conditions of at least 9.0 are optimal for carbonate precipitation in reactions of 18 h. Although the reaction duration is not long enough to successfully correlate brine compositional changes with precipitation and pH evolution, X-ray diffraction analysis clearly confirms the presence of calcite. Scanning electron microscopy/en...

Thermodynamic evaluation of hot brine stimulation for natural gas hydrate dissociation

Abstract: In order to evaluate the efficiency of producing gas from natural gas hydrate (NGH), NGH dissociation under thermal stimulation is treated as a moving-boundary problemBased on a mathematical model assuming that dissociation of hydrate in the porous media takes place in constant temperature boundary condition,the analytical temperature distributions in dissociated and undissociated zones were solved, and thermal efficiency and energy efficiency were derivedA comparison of hot water injection case and brine injection case for the same heat injection rate showed higher thermal and energy efficiency for the brine case than the hot water caseThermal efficiency was commonly 40%—70% During dissociation of hydrate by injecting 300—450 K, 0—15%(mass) hot brine,energy efficiency varied between 74% and 113% From this point of view, hot brine injection is a feasible and economical way of NGH production

Feasibility Study of Using Brine for Carbon Dioxide Capture and Storage from Fixed Sources

Abstract: A laboratory-scale reactor was developed to evaluate the capture of carbon dioxide (CO2) from a gas into a liquid as an approach to control greenhouse gases emitted from fixed sources. CO2 at 5-50% concentrations was passed through a gas-exchange membrane and transferred into liquid media--tap water or simulated brine. When using water, capture efficiencies exceeded 50% and could be enhanced by adding base (e.g., sodium hydroxide) or the combination of base and carbonic anhydrase, a catalyst that speeds the conversion of CO2 to carbonic acid. The transferred CO2 formed ions, such as bicarbonate or carbonate, depending on the amount of base present. Adding precipitating cations, like Ca++, produced insoluble carbonate salts. Simulated brine proved nearly as efficient as water in absorbing CO2, with less than a 6% reduction in CO2 transferred. The CO2 either dissolved into the brine or formed a mixture of gas and ions. If the chemistry was favorable, carbonate precipitate spontaneously formed. Energy expenditure of pumping brine up and down from subterranean depths was modeled. We conclude that using brine in a gas-exchange membrane system for capturing CO2 from a gas stream to liquid is technically feasible and can be accomplished at a reasonable expenditure of energy.

Synthesis of a red iron oxide/montmorillonite pigment in a CO2-rich brine solution.

Abstract: The homoionic calcium-montmorillonite was used to synthesize a red iron oxide/clay pigment in a CO2-rich brine solution (0.5 M of NaCl) by using an agitated batch-reactor (engineer autoclave). The operating conditions were 15 days of reaction, 200 bars of pressure and 150 °C of temperature. SEM/EDS, STEM/EDS, XRD and Infrared Spectrometry were performed to characterize before and after reaction the solid phase. The results showed the precipitation of spherical nanoparticles (50–500 nm) of iron oxide (Fe2O3) dispersed and/or coagulated in the clay-matrix. Evidently, this oxide produced red coloration in the final product. For this case, the Fe3+ cation was provided to the aqueous solution by the dissolution of Ca-montmorillonite, particularly, the dissolution of most fine particles contained in the starting clay material. The cation exchange process and precipitation of polymorph silica were also observed.

Composition and method for thickening heavy aqueous brines

Abstract: A process of preparing a well servicing fluid comprising viscosifying a heavy brine by contacting with a cationic polysaccharide and a composition thereof.

Use of urea-formaldehyde resin in potash ore flotation

Abstract: A potash ore processing method for the recovery of potassium minerals from potash ore can comprises conditioning a pulped potash ore, wherein the potash ore comprises a potassium chloride component and a clay component, in a saturated brine solution with an effective amount of brine dispersible urea-formaldehyde resin or modified brine dispersible urea-formaldehyde resin. In some embodiments, the processing method requires little or no frother and/or reduced amounts of flocculent while achieving potassium mineral recovery at least as good as the equivalent process without the urea-formaldehyde resin. In addition, the separation of clay waste from saturated brine for the reuse of the brine can be made more efficient through the use of urea-formaldehyde resin.

Thermal desalination plant integrated upgrading process and apparatus

Abstract: The invention relates to improvements in the thermal desalination processes involving multistage flash distillation (MSF), multi-effect distillation (MED) and vapour compression (VC) generally and in particular in an application to seawater desalination to produce potable water. The invention discloses a process of integrated plant modifications and apparatus to enable significant upgrading in the capacity of the thermal desalination plants, based on the increase of brine recirculation flow and increase of the top brine temperature. Modifications include the provision of increased pumping to up rate pressure and flow rate, removing non-condensables using venting, provision of a barometric condenser, increasing demister area, increasing make up flow and blow down rate, adjustment of brine flash orifices, injecting acid into the brine recirculation flow, using hybrid combinations including nanofiltration or reverse osmosis, introducing scale inhibitors, scale control chemicals, and sequestering agents, sponge ball cleaners and water softening.

Installation for producing a disinfectant by electrolysis

Abstract: An assembly produces a disinfectant agent to purify water and/or aqueous solutions. The assembly has a brine tank (4), an electrolysis module (EM) to generate split water that is effective as a disinfectant. The brine tank (4) and electrolysis module (EM) are linked to the demineralised water treatment assembly by a pipe (3). The demineralised water treatment assembly has an ion exchanger, or a distillation assembly, or a reverse osmosis unit. The brine tank has a low concentration (less than 0.9%) of ultra-pure sodium chloride that is fed to the electrolysis module for generation of the disinfectant. Operation of the electrolysis module is determined by a measuring device (7) that determines the conductivity, pH and/or redox potential of the disinfectant, together with the central control unit (ZM).

Interactions between chloride and sulfate or silica removals using an advanced lime-aluminum softening process.

Abstract: An advanced softening process called the ultra-high lime with aluminum process (UHLA) was initiated in this research. The UHLA process has the ability to remove sulfate, silica, and chloride from waters such as recycled cooling water and desalination brines. Furthermore, it can remove other scale-forming materials, such as calcium, magnesium, carbonate, and phosphate. The purpose of this paper is to study the interactions among chloride, sulfate, and silica in the UHLA process. Results of equilibrium experiments indicated that sulfate is preferentially removed over chloride. Final chloride concentration increased with increasing initial sulfate concentration. However, initial chloride concentration was found to have negligible effect on final sulfate concentration. Silica was found to have only a small effect on chloride removal.

Organocatalytic Direct Michael Reaction of Ketones and Aldehydes with β-Nitrostyrene in Brine.

Abstract: We have developed a direct, asymmetric Michael reaction that can be performed in brine or seawater without addition of organic solvents. A bifunctional catalyst with long hydrophobic alkyl chains efficiently catalyzed Michael reactions and afforded the desired products in excellent yield with high enantiomeric excess, even when only an equal molar ratio of the donor to acceptor was used.

Fluid loss pills

Abstract: A fluid loss pill that includes a crosslinked polymer gel, a brine, and solid salt particles disposed in said gel is described. Further, a method for reducing fluid loss that includes pumping a selected amount of a fluid loss pill into a wellbore leading to an oil-, condensate-, or gas-producing formation, the fluid loss pill including a crosslinked polymer gel, a brine, and solid salt particles disposed in said gel is described.

Calculation of the thermal loads of an ice rink using a zonal model and building energy simulation software

Abstract: A municipal ice rink in Montreal was modeled and its transient thermal behavior was evaluated for a typical year using a zonal model coupled to building energy simulation software. The calculated temperatures of the air above the ice and that of the southern wall are close to the corresponding measured values. The results show the seasonal effects as well as those of the occupation and the resurfacing on the temperature of the ice, the temperature of the air, and the average and maximum monthly load transmitted toward the brine. They also show the effect of the airflow in the interior ofthe building on the temperatures and loads. Parametric studies were carried out to determine the effects of the ventilation air temperature and the average brine temperature on the refrigeration load, the ice temperature, and the air temperature above the stands.

Corrosion and Galvanic Behavior of Copper and Copper-Brazed Joints in Heavy Brine Lithium Bromide Solutions

Abstract: The objective of the present work was to study systematically the corrosion resistance of copper-brazed joints in 400, 700, and 850 g/L, and commercial lithium bromide (LiBr) heavy brine s...