Steam Vapor Research Articles

Extract of Scutellaria baicalensis inhibits dengue virus replication.

BackgroundScutellaria baicalensis (S. baicalensis) is one of the traditional Chinese medicinal herbs that have been shown to possess many health benefits. In the present study, we evaluated the in vitro antiviral activity of aqueous extract of the roots of S. baicalensis against all the four dengue virus (DENV) serotypes.MethodsAqueous extract of S. baicalensis was prepared by microwave energy steam evaporation method (MEGHE™), and the anti-dengue virus replication activity was evaluated using the foci forming unit reduction assay (FFURA) in Vero cells. Quantitative real-time polymerase chain reaction (qRT-PCR) assay was used to determine the actual dengue virus RNA copy number. The presence of baicalein, a flavonoid known to inhibit dengue virus replication was determined by mass spectrometry.ResultsThe IC50 values for the S. baicalensis extract on Vero cells following DENV adsorption ranged from 86.59 to 95.19 μg/mL for the different DENV serotypes. The IC50 values decreased to 56.02 to 77.41 μg/mL when cells were treated with the extract at the time of virus adsorption for the different DENV serotypes. The extract showed potent direct virucidal activity against extracellular infectious virus particles with IC50 that ranged from 74.33 to 95.83 μg/mL for all DENV serotypes. Weak prophylactic effects with IC50 values that ranged from 269.9 to 369.8 μg/mL were noticed when the cells were pre-treated 2 hours prior to virus inoculation. The concentration of baicalein in the S. baicalensis extract was ~1% (1.03 μg/gm dried extract).ConclusionsOur study demonstrates the in vitro anti-dengue virus replication property of S. baicalensis against all the four DENV serotypes investigated. The extract reduced DENV infectivity and replication in Vero cells. The extract was rich in baicalein, and could be considered for potential development of anti-DENV therapeutics.

The Research on Atmospheric Pressure Water Vapour Plasma Generation and Application for the Destruction of Wastes

In the Lithuanian Energy Institute an experimental atmospheric pressure Ar/water vapour plasma torch has been designed and tested. The power of plasma torch was estimated 40 ÷ 69 kW, the mean temperature of plasma jet at the exhaust nozzle was 2300÷2900K. The chemical compositionof water vapour plasma was established from the emission spectrum lines at 300 ÷ 800nm range. The main species observed in Ar/water vapour plasma were: Ar, OH, H, O, Cu. The experiments on water vapour steam reforming were performed. The results confirmed that water vapour plasma has the unique properties – high enthalpy and environmentally friendly conditions. It could be employed for environmental purposes such as destruction of wastes into simple molecules or conversion to synthetic gas.

G081023 温風空気による褐炭の乾燥特性に関する研究([G081-02]動力エネルギーシステム技術の最前線(2))

Half of coal reserves are low grade coal which has low calorific value. The low grade coal must be used effectively to utilize the coal resource over a long period of time. Brown coal has a lot of moisture in inside and about 2/3 of mass is moisture. When the brown coal burns for fuel of power generation, latent heat of steam evaporation causes thermal loss. For this reason, decrease of thermal efficiency occurs for brown coal utilization. Since the brown coal has low degree of carbonization, spontaneous ignition and explosion easily occur during drying process. Although we want to establish a drying technique of brown coal, the details of drying property of brown coal are not clarified and drying time of brown coal cannot be predicted exactly. In the present study, numerical model of single particle of brown coal in hot air flow was constructed and the drying property of brown coal was investigated.

Microstructure Devices for efficient Evaporation of Liquids

Different microstructure devices used for evaporation and generation of steam are described in this publication. Starting with simple liquid-heated devices, electrically powered devices containing micro channels as well as non-channel microstructures are shown. An electrically powered device for optical inspection of the microstructures and the processes inside has been designed and manufactured. Exchangeable metallic micro channel array foils as well as an optical inspection of the evaporation process by high-speed videography have been integrated into this test system. Fundamental research onto the influences of the inlet flow distribution system geometry and the geometry and dimensions of the micro channels have been performed. A pre-calculation sheet for micro evaporators with micro channel arrays based on the measurement of inlet parameters for the liquid only was generated. While evaporation of liquids in micro channel devices of more or less conventional design is possible, it is, in many cases, not feasible to generate superheated steam due to certain boundary conditions. Therefore a new design was proposed to obtain complete evaporation and steam superheating, consisting of an arrangement of numerous circular blanks with connecting nozzles. A maximum power density of 1400 kW · m−2 has been transferred while water could be completely evaporated and the generated steam superheated.

Time lag between carbon dioxide influx to and efflux from bare saline-alkali soil detected by the explicit partitioning and reconciling of soil CO2 flux

A recent publication demonstrated a non-biological CO2 absorption by saline-alkali soils (Aa) at desert ecosystems. Still little is known about the mechanisms of Aa and it might be a hidden loop in the carbon cycle. Although it was separated after sterilization treatment on bare saline-alkali soils by high-temperature vapor steam method, its contributions to soil CO2 influx and efflux remain undiscussed. Even the separation of biological and non-biological components from measured Fa remains unresolved. Therefore the evaluation on the time lag between carbon dioxide influx to and efflux from bare saline-alkali soils is rather complicated and hence admits more uncertainty. This manuscript was designed to detect the time lag between carbon dioxide influx to and efflux from saline-alkali soils. We focus on bare saline-alkali soils to cut down uncertainty. Some data of this study are collected from the Tarim River Basin [87°56′E, 44°17′N; elevation: 461 m].Considering potential influence of Aa to CO2 influx and efflux, we partition Fa into three components, Rm, Aa and their interaction ima. It is demonstrated that diurnal time lag between Aa and Rm is about 2 h. The contributions of Aa definitely prolongs the period of Rm to maximum. To our surprise, there exists a significant time lag between Fa and Rm, about 1 h, which can be merged after reconciling Fa as a direct sum of total CO2 influx and efflux. Further between-ecosystem comparisons suggest that the surprised time lag between Fa and Rm should be attributed to the contributions of Aa and Rm in ima.

Downhole Steam Generation Pushes Recovery Beyond Conventional Limits

This article, written by Editorial Manager Adam Wilson, contains highlights of paper SPE 150515, ’Advancing Thermal and Carbon Dioxide Recovery Methods Beyond Their Conventional Limits: Downhole Innovation,’ by Laura Capper, SPE, CAP Resources; Myron Kuhlman, SPE, MK Tech Solutions; George Vassilellis, SPE, Gaffney Cline & Associates; M.J. Schneider, Global Marine Drilling Company; and Nick Fitzpatrick, World Energy Systems, prepared for the 2011 SPE Heavy Oil Conference and Exhibition, Kuwait City, Kuwait, 12-14 December. The paper has not been peer reviewed. Enhanced oil recovery (EOR) is a general term used for processes that seek to improve recovery of hydrocarbons from a reservoir after the primary production phase. EOR is designed to increase the mobility of the oil, with an objective of improving oil sweep efficiency or enabling lower residual-oil saturation. Downhole steam generation (DHSG), which combines thermal and nitrogen or CO2 EOR, offers several benefits to accelerate the production of oil. Moreover, the CO2 that is generated in situ can be used elsewhere. Conventional-EOR Limitations Surface-Steam-Injection Limitations. Steam that has 100% quality consists entirely of vapor, whereas 0% steam quality is liquid water. Higher-quality steam, therefore, contains much more energy than lower-quality steam, and higher steam quality (generally greater than 60%) results in more-effective oil recovery. The steam vapor transfers heat to the oil, lowering its viscosity, and, when it condenses, the resulting water drives the oil toward the producer well. A simulation and field economic model for a 2,000-ft-deep reservoir in California showed that steam quality drops to 50% or below at approximately 700 m (approximately 2,300 ft). There-fore, surface steam injection is generally limited to reservoirs no deeper than 800 m and, more typically, is applied in reservoirs less than 500 m deep. CO2 Limitations. CO2 use is largely dependent on the reservoir’s proximity to large natural sources or large refineries, chemical plants, or gas plants that produce nearly pure CO2. Because oil fields are not necessarily near these sources, pipelines have been the main source of CO2, and their availability and cost limit applications of CO2 EOR. When reservoir pressure is too low or oil gravity is too high, much of the CO2 does not dissolve in the oil. However, at high pressure, enough CO2 (40–60 mol%) dissolves in the oil to improve heavy-oil recovery by causing the oil to swell, reducing the oil’s density and improving mobility. Conventional In-Situ-Combustion Limitations. In both light- and heavy-oil reservoirs, burning some of the oil in situ creates a combustion zone that moves through the formation. In deep light-oil reservoirs, in-situ combustion (ISC) (or high-pressure air injection) is a method of generating an inert gas from spontaneous combustion of the oil at temperatures above 75°C. This provides pressure maintenance to the reservoir. In heavy-oil reservoirs, combustion creates a steam drive (whose size depends on connate water or the amount of injected water) and an inert-gas drive for the recovery of oil.

Numerical analysis of contaminant removal from fractured rock during boiling

A multiphase heat transfer numerical model is used to simulate a laboratory experiment of contaminant removal at boiling temperatures from a rock core representing the matrix adjacent to a fracture. The simulated temperature, condensate production, contaminant and bromide concentrations are similar to experimental data. A key observation from the experiment and simulation is that boiling out approximately 1/2 pore volume (50mL) of water results in the removal of essentially 100% of the dissolved volatile contaminant (1,2-DCA). A field-scale simulation using the multiple interacting continua (MINC) discretization approach is conducted to illustrate possible applications of thermal remediation of fractured geologic media, assuming uniform heating. The results show that after 28% of the pore water (including both steam vapor and liquid water) was extracted, and essentially all the 1,2-DCA mass (more than 99%) was removed.

Biofilms on environmental surfaces: Evaluation of the disinfection efficacy of a novel steam vapor system

Environmental surfaces in health care settings are often contaminated by microorganisms, and biofilms can develop on the surfaces in these settings. Steam vapor technology is of potential use for disinfection of biofilms on the environmental surfaces. We tested the disinfection efficacy of a thermal-accelerated nanocrystal sanitation (TANCS)-equipped steam vapor technology against biofilms through disinfecting biofilms developed by 4 bacterial strains-Escherichia coli, Acinetobacter baumannii, Pseudomonas aeruginosa, and Staphylococcus aureus-on an identical test surface (ie, polycarbonate) and biofilms developed by E coli on 4 different test surfaces: polycarbonate, rubber, stainless steel, and ceramics. Our data show that a 3-second steam treatment rapidly killed each biofilm tested (>99.95 % killing efficiency). For biofilms developed on different surfaces, 3-second steam treatment achieved 99.95% killing of E coli biofilms developed on different surfaces. Compared with chemical disinfection, steam treatment for <1 second a similar level of biofilm disinfection as provided by incubation with 10-ppm sodium hypochlorite (bleach) for 10-20 minutes of contact time. Our data suggest that the TANCS-equipped steam vapor disinfection is an emerging and potentially useful technology for disinfecting biofilms on environmental surfaces.

Comparison of different solar plants based on parabolic trough technology

Solar thermal plants are among the most promising technologies to replace fossil fuel stationary applications, and within solar thermal technologies, parabolic troughs are considered the most mature application in the market. This paper compares different solar field technologies, in terms of both performance at design conditions and annual energy production; an in-house code, PATTO, was used to perform energy balances. We considered a reference case reflecting state-of-the-art Nevada Solar One, which showed a design efficiency and annual average efficiency of 22.4% and 15.3%, respectively, in agreement with actual performance. If solar salts are used as heat-transfer fluid instead of synthetic oil (e.g. ARCHIMEDE plant), the efficiency improved within the range of 6% due to the higher maximum temperature. Further thermodynamic advantages can be achieved with a direct steam generation plant; the main drawback is the more complex transient control and no commercially available storage systems. We propose the innovative Milan configuration, which combines advantages of direct steam evaporation and the use of a heat-transfer fluid, to investigate both synthetic oil and solar salts for steam superheating and reheating. Results for this configuration are very promising, with a sun-to-electric annual average efficiency of 17.8%, which is 16% higher than the reference case. Detailed daily simulations showed that advantages are more significant at low radiation. However, the plant should be optimized on an economic basis and we will discuss this in a future paper.

KARAKTERISITIK FLOW PATERN PADA ALIRAN DUA FASE GAS-CAIRAN MELEWATI PIPA VERTIKAL

Multi-phase flows are widely encountered in several engineering and industrial facilities, such as conventional steam power plants, evaporators and condensers, pressurized-water nuclear reactors, a wide variety of petroleum industries, chemicals and food processing industries. Surely, in the complex pipeline installation of these systems, vertical pipe will be commonly used for pipe connection. The purpose of this work is to investigate the flow pattern of gas-liquid two phase in the vertical pipe. Experiments will be performed in a 36 mm ID acrylic pipe vertical. Superifical liquid velocities and volumetric gas quality will be varied 0.3~1,1 m/s and 0.05~0.2 respectively. Digital camera will be used for flow pattern visualization in the vertical pipe. It was observed that effect of vertical pipe on flow pattern formed cluster bubbly flow for low volumetric gas quality with high superifical liquid velocities. For superifical liquid velocities with medium volumetric gas quality formed homogeneous bubbly flow and high volumetric gas quality is dense bubbly flow.

Selected abiotic factors that influence raw cow milk freezing point depression

Freezing point depression (FPD) is an important property of milk that is influenced primarily by milk components connected to osmotic pressure. Under certain conditions it is possible to detect the addition of water to milk. It is necessary to have the right FPD limit in legislation for milk quality control. The aim of this study was to improve the estimation procedure of this limit. Apart from factors related to dairy cow nutrition, cattle breed and milk yield, it is important to take into account CO2 (6%), water steam evaporation and pasteurization under technological conditions. Bulk milk samples (1, 30, 6, 6, 10, 1 according to experiment) from Holstein and Czech Fleckvieh breed (1:1) were used in the experiments and technologically treated. The effects of water addition (water saturated and unsaturated by CO2), carbon dioxide evaporation and pasteurization (80 °C for 22 min) were quantified. Pasteurization aggravation of FPD was -0.00394 ± 0.00171 ºC (P &lt; 0.001). Aggravation due to carbon dioxide evaporation could be -0.00383 ± 0.00095 ºC (P &lt; 0.001) depending on practice. Increase in FPD is recorded after milking during technological procedures of milk storage, mixing, pumping, transport shaking and warming. During FPD shift, the acuteness of FPD data sets increases. This fact should be considered in the process of deriving standard raw cow milk FPD limits. Similar experimental analysis of milk FPD technological shifts has not been performed in this way until now.

Exergoeconomic optimization of a trigeneration system for heating, cooling and power production purpose based on TRR method and using evolutionary algorithm

Abstract In the present study, exergoeconomic optimization of a trigeneration system for cooling, heating and power purposes has been carried out. The system is made up of air compressor, combustion chamber, gas turbine, dual pressure heat recovery steam generator and absorption chiller in order to produce cooling, heating and power. The design parameters of this study are selected as: air compressor pressure ratio, gas turbine inlet temperature, pinch point temperatures in dual pressure heat recovery steam generator, pressure of steam that enters the generator of absorption chiller, process steam pressure and evaporator of the absorption chiller chilled water outlet temperature. The economic model used in this research is according to the total revenue requirement (TRR) and the cost of the total system product was defined as our objective function and optimized using a Genetic Algorithm technique. Results of exergoeconomic optimization are compared with corresponding features of the base case system. It has seen that objective function was modified about 15 percent after optimization. Furthermore, a sensitivity analysis has been presented in order to investigate the effects of decision variables on the different objective functions. Decision makers may find the methodology explained in this paper, very useful for optimal comparison and selection of trigeneration systems.

Assessment of Standby Evaporator as an Energy Conservation Measure: Case of Sudanese Sugar Industry

This work presents analysis of historical data of four Sudanese sugar factories namely Assalaya, Sennar, Gunned and New Halfa. The historical data covers more than 40 years (1966–2010). In about 38 years (1966–2004) of this period the sugar industry operates with one set of evaporator. In 2005 a standby set of evaporator is installed in each factory. The installed set of evaporator is similar in configuration (Robert type) to existing set however, with a relatively large heat transfer area and made of stainless steel rather than brass. The result of the analysis revealed that before 2004 the total downtime is 26.6% (53 days) of the operation period on average; 10.4 days (19.6%) of which is for evaporator scale removal. The provision of standby evaporator has completely eliminated the evaporator downtime. The improvement in total downtime has made significant saving on bagasse. The bagasse saved in 10 days is 14379 ton ($215691 based on bagasse price $15/ton). The shortening of crop season made by standby evaporator has saved the sugar cane from over maturation and improved sugar recovery by 0.2% (from 9.3 to 9.5%). The savings due to bagasse and sugar recovery only made the evaporator payback period of 2.8 years. The standby evaporator has also improved the overall steam economy and evaporation coefficient. The steam economy of the standby and existing sets of evaporators is about 3.1 and 2.6 respectively.

Reduction in the microbial load on high-touch surfaces in hospital rooms by treatment with a portable saturated steam vapor disinfection system

Recent scientific literature suggests that portable steam vapor systems are capable of rapid, chemical-free surface disinfection in controlled laboratory studies. This study evaluated the efficacy of a portable steam vapor system in a hospital setting. The study was carried out in 8 occupied rooms of a long-term care wing of a hospital. Six surfaces per room were swabbed before and after steam treatment and analyzed for heterotrophic plate count (HPC), total coliforms, methicillin-intermediate and -resistant Staphylococcus aureus (MISA and MRSA), and Clostridium difficile. The steam vapor device consistently reduced total microbial and pathogen loads on hospital surfaces, to below detection in most instances. Treatment reduced the presence of total coliforms on surfaces from 83% (40/48) to 13% (6/48). Treatment reduced presumptive MISA (12/48) and MRSA (3/48) to below detection after cleaning, except for 1 posttreatment isolation of MISA (1/48). A single C difficile colony was isolated from a door push panel before treatment, but no C difficile was detected after treatment. The steam vapor system reduced bacterial levels by >90% and reduced pathogen levels on most surfaces to below the detection limit. The steam vapor system provides a means to reduce levels of microorganisms on hospital surfaces without the drawbacks associated with chemicals, and may decrease the risk of cross-contamination.

Gas Release Behavior of Alloyed Steel Powder by Gas Chromatography

In recent years, with increasing of a demand of alloyed steel powder, knowledge of gas release behavior has been required to improve the quality of the produced material. In this paper, the gas release behavior from Fe powder, Fe-Cr powder, Fe-Ni powder, and Fe-Cr-Ni powder during heating in pure He gas were investigated by a gas chromatography analyzer. CO2, H2O, and C3H8 gases were detected from the powders. Especially, in Fe powder and Fe-Ni powder, CO2 gas was remarkably released over 600°C. H2O gas generation was detected from Fe-Ni powder and Fe-Cr-Ni powder in temperature range of 200-600°C. The amount of CO2 gas in Fe powder and Fe-Ni powder was clearly higher than that in Fe-Cr powder and Fe-Cr-Ni powder. Additionally, the amount of H2O gas in Fe-Ni powder and Fe-Cr-Ni powder was also higher than that in Fe powder and Fe-Cr powder. Precisely, it was guessed that CO2 gas release behavior depended on the Cr component in the alloyed steel powder, and that H2O gas release behavior rerated with Ni component. As comparative experiments, the gas release behavior of pure Cr powder, pure Ni powder, and NiO powder were studied. Furthermore, for the alloyed steel powder mixed with carbon powder, and for the alloyed steel powder treated in steam vapor, the amount of gas release were measured. From these investigations, the effects of Cr and Ni components against the gas release behavior of the alloyed steel powder were discussed in this paper.

Pore-Level Investigation of Heavy Oil and Bitumen Recovery Using Solvent −Aided Steam Assisted Gravity Drainage (SA-SAGD) Process

Attempts have been made to reduce the energy requirements of steam assisted gravity drainage (SAGD) projects through coupled thermal and solvent processes (i.e., hybrid SAGD). The augmented process brings superior features to the SAGD process in terms of reduced energy requirement, enhanced produced oil quality, and also improved oil recoveries. The pore-level recovery mechanisms of the hybrid SAGD process have not been investigated yet. The main objective of this paper is to visually investigate and to document the pore-scale events during the hybrid SAGD process using glass micromodel type of porous media. Different additives (n-pentane and n-hexane) were added to steam prior to injecting into the models. Experiments were conducted in an inverted-bell vacuum chamber to reduce the excessive heat loss to the surroundings. The results indicate that the gravity drainage process takes place through a layer of pores composed of 1−5 pores in thickness, in the direction perpendicular to the nominal oil−gaseous mixture interface, in the mobilized region. The interplay between gravity and capillary forces results in the drainage of the mobilized oil. The visualization results demonstrated the coexistence of water-in-oil and solvent-in-water emulsification at the interface because of the local condensation of both steam and the vaporized solvent. The extent of emulsification depends directly on the temperature gradient between the gaseous mixture and the mobile oil phase. Asphaltene precipitation was also observed when the condensed solvent reached the bitumen interface. As the nature of the process involves partially miscible displacements, the extent of film-flow drainage of the mobilized oil was also significant. Other pore-scale phenomena include localized entrapment of steam and vaporized solvent followed by condensation, snap-off of liquid films, steam and solvent vapor condensation at the interface because of the temperature gradient and capillary instabilities.

Gas flow behavior in industrial FCC disengager vessels with different coupling configurations between two-stage separators

The gas flow behaviors and gas residence time distribution in industrial FCC disengager space are numerically studied with the combined consideration of the product gas, stripping gas and anti-coking steam. Although purge steam is used in the top dome in order to alleviate the coke formation in the refinery plants, its effectiveness is still obscure. In this study, the Reynolds stress model is applied to calculate the gas flow field and the scalar transport equations are used to obtain the gas residence time distribution. The species transport equations are used to get the local mass fractions of steam and oil vapors and further to verify the effectiveness of the anti-coking steam. In view of the wide use of “open” configuration, the optimizing position of the primary cyclone outlet is proposed for an industrial case in Qianguo refinery. Based on the results, suggestions are made for improved operation of the industrial units.

Radon in Drinking Water

Firstly, we wish to express to the authors our appreciation of and thanks for their article. They showed the risk for lung cancer while focusing in their discussion mainly on inhaled radon, which penetrates into buildings and residential spaces from underground. We wish to point out a further source of cancer risk, which we think has not received enough attention in the public discussion—namely, the release of radon that is dissolved in drinking water. In Germany, the mean radon activity in drinking water is about 6 Bq/L, although regionally it may exceed 100 Bq/L and even 1000 Bq/L. What happens if the gas is released from the water into the shower cubicle during a warm shower and then inhaled? For a concentration of 100 Bq/L, activity in the shower cubicle will rise by 100 Bq per liter of water used if the radon is fully released (activity describes the number of radioactive breakdowns per second [1 Bq=1 breakdown/second]. For the purposes of describing exposures, using Bq/L or Bq/m3 as the unit of measurement seems appropriate [2]). A few years ago, an American brochure caused shockwaves by reporting values of several kBq/m3 that had been measured in shower cubicles after 15 minutes—a value that is entirely plausible according to the calculation in our example. Is the risk posed by radon inhaled during a shower really negligible, as is often claimed, especially as ventilating the cubicle or cabin during the shower is usually difficult? In the kitchen, the evaporation of steam and the radon concentrated in natural gas constitute an additional radon exposure. Opening the windows is a useful counter-measure in this context. In modern residences with tightly sealed windows, however, thorough ventilation is more problematic. We would welcome a short comment from the authors, outlining their views on the problems of “radon in shower cubicles” and “lacking ventilation in modern residential buildings.” As a result of insufficient ventilation, several other causes of health risks have made the newspaper headlines, including pathogenic indoor climates, concentration of allergens, or fungal (mould) overgrowth.

Numerical analysis of the performance of a thermal ejector in a steam evaporator

Ejectors have been widely used in many applications such as water desalination, steam turbine, refrigeration systems, and chemical plants. The advantage of an ejector system lies in its extremely reliable operation due to the complete absence of moving parts. However, the performance depends on a number of factors, among which the flow channel configuration/arrangement is critical. To improve the performance of an existing thermal compressor in a steam evaporator, a comprehensive study was conducted in this paper with a main focus on the sensitivity of performance to the geometric arrangement. Numerical simulation was employed to investigate the thermal-flow behavior. The performance is measured by the entrainment ratio, i.e., the secondary (suction) flow rate from a vapor plenum over the primary steam jet flow. It is observed that any downstream resistance will seriously impede the suction flow rate. In addition, the entrainment ratio is sensitive to the location of the jet exit, and there is an optimum location where the primary flow should be issued. A well-contoured diffuser can increase the entrainment ratio significantly. However, the size of suction opening to the plenum is less important, and a contoured annular passage to guide the entrained flow shows little effect on the overall performance. Based on the numerical results the steam entrainment rate of the best case in the confinement of the current study is approximately 430% of the jet flow rate, while some cases with mediocre design can only produce an entrainment of 24% of the primary jet flow.

Experimental Demonstration of Contaminant Removal from Fractured Rock by Boiling

This study was conducted to experimentally demonstrate removal of a chlorinated volatile organic compound from fractured rock by boiling. A Berea sandstone core was contaminated by injecting water containing dissolved 1,2-DCA (253 mg/L) and sodium bromide (144 mg/L). During heating, the core was sealed except for one end, which was open to the atmosphere to simulate an open fracture. A temperature gradient toward the outlet was observed when boiling occurred in the core. This indicates that steam was generated and a pressure gradient developed toward the outlet, pushing steam vapor and liquid water toward the outlet. As boiling occurred, the concentration of 1,2-DCA in the condensed effluent peaked up to 6.1 times higher than the injected concentration. When 38% of the pore volume of condensate was produced, essentially 100% of the 1,2-DCA was recovered. Nonvolatile bromide concentration in the condensate was used as an indicator of the produced steam quality (vapor mass fraction) because it can only be removed as a solute, and not as a vapor. A higher produced steam quality corresponds to more concentrated 1,2-DCA removal from the core, demonstrating that the chlorinated volatile compound is primarily removed by partitioning into vapor phase flow. This study has experimentally demonstrated that boiling is an effective mechanism for CVOC removal from the rock matrix.