Concentrations Of Dissolved Solids Research Articles

Composite Geochemical Database for Coalbed Methane Produced Water Quality in the Rocky Mountain Region

Coalbed methane (CBM) or coalbed natural gas (CBNG) is an unconventional natural gas resource with large reserves in the United States (US) and worldwide. Production is limited by challenges in the management of large volumes of produced water. Due to salinity of CBM produced water, it is commonly reinjected into the subsurface for disposal. Utilization of this nontraditional water source is hindered by limited knowledge of water quality. A composite geochemical database was created with 3255 CBM wellhead entries, covering four basins in the Rocky Mountain region, and resulting in information on 64 parameters and constituents. Database water composition is dominated by sodium bicarbonate and sodium chloride type waters with total dissolved solids concentrations of 150 to 39,260 mg/L. Constituents commonly exceeding standards for drinking, livestock, and irrigation water applications were total dissolved solids (TDS), sodium adsorption ratio (SAR), temperature, iron, and fluoride. Chemical trends in the basins are linked to the type of coal deposits, the rank of the coal deposits, and the proximity of the well to fresh water recharge. These water composition trends based on basin geology, hydrogeology, and methane generation pathway are relevant to predicting water quality compositions for beneficial use applications in CBM-producing basins worldwide.

Effects of Propionic Acid and pH on Ethanol Fermentation by Saccharomyces cerevisiae in Cassava Mash

The effects of propionic acid on ethanol and glycerol production by Saccharomyces cerevisiae in cassava mash were examined along with the influence of pH (4.0, 5.0, and 6.0) and of dissolved solids content (22%, 25%, and 27%). Inhibition by propionic acid increased as solids content increased and medium pH declined. Complete inhibition of ethanol fermentation was observed in mashes at pH 4.0 (60 mM propionic acid for 22% solids and 45 mM for 25% and 27%). Glycerol production linearly decreased with increased undissociated propionic acid concentration in all mashes at all pH levels, which partly contributed to increased final ethanol production when propionic acid concentration in mashes was low (≤ 30 mM).

Assessment of desalination technologies for high saline brine applications — Discussion Paper

Treatment and/or disposal of concentrated brines, which have total dissolved solids content in the region of 70,000 ppm up to full saturation, are a common and important problem around the world. The success of any desalination technology for such an application depends on the reliability of the process, product quality, capital cost, energy consumption, complexity of the process and safe disposal. A comprehensive study of the reasons why desalination technologies have limited scope in the treatment/disposal of these brines is considered in terms of economical and technical aspects. Zero liquid discharge systems and other promising desalination technologies (such as osmotic power plants and freeze-melting processes) which could be used for treating high saline brines have also been investigated in this paper.

Groundwater chemistry near an impoundment for produced water, Powder River Basin, Wyoming, USA

Summary The Powder River Basin is one of the largest producers of coal-bed natural gas (CBNG) in the United States. An important environmental concern in the Basin is the fate of the large amounts of groundwater extracted during CBNG production. Most of this produced water is disposed of in unlined surface impoundments. A 6-year study of groundwater flow and water chemistry at one impoundment, Skewed Reservoir, has produced the most detailed data set for any impoundment in the Basin. Data were collected from a network of 21 observation wells and three suction lysimeters. A groundwater mound formed atop bedrock within initially unsaturated, unconsolidated deposits underlying the reservoir. Heterogeneity in physical and chemical properties of sediments resulted in complex groundwater flow paths and highly variable groundwater chemistry. Sulfate, bicarbonate, sodium, and magnesium were the dominant ions in all areas, but substantial variability existed in relative concentrations; pH varied from less than 3 to more than 9, and total dissolved solids concentrations ranged from less than 5000 to greater than 100,000 mg/L. Selenium was a useful tracer of reservoir water; selenium concentrations exceeded 300 μg/L in samples obtained from 18 of the 24 sampling points. Groundwater travel time from the reservoir to a nearby alluvial aquifer (a linear distance of 177 m) was calculated at 474 days on the basis of selenium concentrations. The produced water is not the primary source of solutes in the groundwater. Naturally occurring salts and minerals within the unsaturated zone, dissolved and mobilized by infiltrating impoundment water, account for most of the solute mass in groundwater. Gypsum dissolution, cation-exchange, and pyrite oxidation appear to be important reactions. The complex geochemistry and groundwater flow paths at the study site underscore the difficulty in assessing effects of surface impoundments on water resources within the Powder River Basin.

Recent and Historic Drivers of Landscape Change in the Everglades Ridge, Slough, and Tree Island Mosaic

More than half of the original Everglades extent formed a patterned peat mosaic of elevated ridges, lower and more open sloughs, and tree islands aligned parallel to the dominant flow direction. This ecologically important landscape structure remained in a dynamic equilibrium for millennia prior to rapid degradation over the past century in response to human manipulation of the hydrologic system. Restoration of the patterned landscape structure is one of the primary objectives of the Everglades restoration effort. Recent research has revealed that three main drivers regulated feedbacks that initiated and maintained landscape structure: the spatial and temporal distribution of surface water depths, surface and subsurface flow, and phosphorus supply. Causes of recent degradation include but are not limited to perturbations to these historically important controls; shifts in mineral and sulfate supply may have also contributed to degradation. Restoring predrainage hydrologic conditions will likely preserve remaining landscape pattern structure, provided a sufficient supply of surface water with low nutrient and low total dissolved solids content exists to maintain a rainfall-driven water chemistry. However, because of hysteresis in landscape evolution trajectories, restoration of areas with a fully degraded landscape could require additional human intervention.

Geochemical heterogeneity in a small, stratigraphically complex moraine aquifer system (Ontario, Canada): interpretation of flow and recharge using multiple geochemical parameters

The Waterloo Moraine is a stratigraphically complex system and is the major water supply to the cities of Kitchener and Waterloo in Ontario, Canada. Despite over 30 years of investigation, no attempt has been made to unify existing geochemical data into a single database. A composite view of the moraine geochemistry has been created using the available geochemical information, and a framework created for geochemical data synthesis of other similar flow systems. Regionally, fluid chemistry is highly heterogeneous, with large variations in both water type and total dissolved solids content. Locally, upper aquifer units are affected by nitrate and chloride from fertilizer and road salt. Typical upper-aquifer fluid chemistry is dominated by calcium, magnesium, and bicarbonate, a result of calcite and dolomite dissolution. Evidence also suggests that ion exchange and diffusion from tills and bedrock units accounts for some elevated sodium concentrations. Locally, hydraulic “windows” cross connect upper and lower aquifer units, which are typically separated by a clay till. Lower aquifer units are also affected by dedolomitization, mixing with bedrock water, and locally, upward diffusion of solutes from the bedrock aquifers. A map of areas where aquifer units are geochemically similar was constructed to highlight areas with potential hydraulic windows.

Sources and Distribution of Organic Compounds Using Passive Samplers in Lake Mead National Recreation Area, Nevada and Arizona, and Their Implications for Potential Effects on Aquatic Biota

The delineation of lateral and vertical gradients of organic contaminants in lakes is hampered by low concentrationsand nondetection of many organic compounds in water. Passive samplers (semipermeable membrane devices [SPMDs] and polar organic chemical integrative samplers [POCIS]) are well suited for assessing gradients because they can detect synthetic organic compounds (SOCs) at pg L(-1) concentrations. Semi-permeable membrane devices and POCIS were deployed in Lake Mead, at two sites in Las Vegas Wash, at four sites across Lake Mead, and in the Colorado River downstream from Hoover Dam. Concentrations of hydrophobic SOCs were highest in Las Vegas Wash downstream from waste water and urban inputs and at 8 m depth in Las Vegas Bay (LVB) where Las Vegas Wash enters Lake Mead. The distribution of hydrophobic SOCs showed a lateral distribution across 10 km of Lake Mead from LVB to Boulder Basin. To assess possible vertical gradient SOCs, SPMDs were deployed at 4-m intervals in 18 m of water in LVB. Fragrances and legacy SOCs were found at the greatest concentrations at the deepest depth. The vertical gradient of SOCs indicated that contaminants were generally confined to within 6 m of the lake bottom during the deployment interval. The high SOC concentrations, warmer water temperatures, and higher total dissolved solids concentrations at depth are indicative of a plume of Las Vegas Wash water moving along the lake bottom. The lateral and vertical distribution of SOCs is discussed in the context of other studies that have shown impaired health of fish exposed to SOCs.

The use of radial basis function networks (RBFN) to predict critical water parameters in desalination plants

The quality of seawater is very important in the design of the pre-treatment unit of any desalination plant. It is worth noting that the operational parameters (salinity and TDS) depend on the seasons (dry or hurricane) such that they are not constants along all year. Recently, new studies indicate that the RBFN is a good tool for prediction of parameters such that the aim of this paper is to apply a RBFN approach as predictive model focus in the context of the Seawater in the Caribbean. The model is obtained taking into account the behaviour of salinity and total dissolved solids content according to the season (dry or hurricane season). The methodology is based on redistributions of centres to locations where input training data possess significant effects can lead to more efficient RBFN. The proposed method herein is based on clustering of input space vectors and computing weights of Euclidian distances and histogram equalization within each cluster will determine the centre and width of each receptive field. The results of this paper indicate that the parameters can change up to 30% along year and the accurate of the prediction obtained can be around 96.7%.

Tailoring the enzymatic synthesis and nanofiltration fractionation of galacto-oligosaccharides

Continuous galacto-oligosaccharides (GOS) synthesis by bead-immobilized β-galactosidase and nanofiltration fractionation of derived sugar mixtures by cellulose acetate membranes are investigated. Upon enzyme adsorption assays (8 mL/g of solution/resin ratio, 150 mg/mL of initial enzyme concentration and 14 ± 1.4 mg protein/g resin), a Langmuir-type isotherm is observed. Enzyme concentration of 10 U/mL, selected in batch reactor experiments, is used for continuous GOS production carried out at lactose concentrations of 150 g/L and 300 g/L, and at 40 °C. Total dissolved solids concentration influences both reaction and saccharide mixtures fractionation. All observed sugar retention coefficients, mainly for monosaccharides, increase with transmembrane pressure and a gap between the retention values of synthesized disaccharides and lactose (87% versus 77%, respectively, for 2 bar/40 °C) is displayed as a function of the effective transmembrane pressure and total sugars concentration. At 150 g/L total sugars in feed, trisaccharides are totally retained. Doubling sugars concentration, trisaccharides retentions decreased for all applied pressures, reaching 90%.

FORMULAS! SELAI PISANG RAJA BULU DENGAN TEMPE DAN DAYA SIMPANNYA

Background: Jelly or jam is preserved foods, typically made from fruit by adding sugar or concentrated dektrosa with total dissolved solids content of at least 65%. Factors to consider in making butter, among others, temperature and sugar content of pectin and citric acid. Some aspects include the type of pectin, acid type and quality of fruit used and the cooking and filling procedures can also impact on the quality of butter, good physical stability and microorganisms. Methods: The addition of tempe in a jam aims to improve the nutritional value of vegetable protein. The study covers the development of formulations of jam, jelly organoleptic test to determine who was elected and also chemical analysis such as protein content, ash content and total sugar content as well as microbiological testing TPC to save power jam. Results: The results showed that the organoleptic test of banana jam and tempe is jam treatment A with the addition of citric acid: pectin = 0.5%: 1%. Results of chemical analysis of the average protein content of 6.1%, an average ash content of 1.80% and average total sugar content 35.57%. During the storage up to week-3, the jam has an average water content of 25.31%- 26.25%; pH range from 5 to 6.15; aw values ranged from 0.75 to 0.83 and the average TPC 1.6 x 102 to 2.2 x 103. From the microbiological test, jam-elect still worth consumed up to week-1 because his total number of microbes that is 4.7 x 102 is still below the maximum limit TPC jam by SNI (5 x 102 colonies / gram).

Stream geochemistry, chemical weathering and CO 2 consumption potential of andesitic terrains, Dominica, Lesser Antilles

Recent studies of chemical weathering of andesitic–dacitic material on high-standing islands (HSIs) have shown these terrains have some of the highest observed rates of chemical weathering and associated CO 2 consumption yet reported. However, the paucity of stream gauge data in many of these terrains has limited determination of chemical weathering product fluxes. In July 2006 and March 2008, stream water samples were collected and manual stream gauging was performed in watersheds throughout the volcanic island of Dominica in the Lesser Antilles. Distinct wet and dry season solute concentrations reveal the importance of seasonal variations on the weathering signal. A cluster analysis of the stream geochemical data shows the importance of parent material age on the overall delivery of solutes. Observed Ca:Na, HCO 3:Na and Mg:Na ratios suggest crystallinity of the parent material may also play an important role in determining weathering fluxes. From total dissolved solids concentrations and mean annual discharge calculations we calculate chemical weathering yields of (6–106 t km −2 a −1), which are similar to those previously determined for basalt terrains. Silicate fluxes (3.1–55.4 t km −2 a −1) and associated CO 2 consumption (190–1575 × 10 3 mol km −2 a −1) determined from our study are among the highest determined to date. The calculated chemical fluxes from our study confirm the weathering potential of andesitic–dacitic terrains and that additional studies of these terrains are warranted.

Water supply development for a new 17.5 MGD (66,200 m3/d) brackish-water RO facility for the City of Hialeah, Florida

Freshwater supply limitations in Southeast Florida have caused a change in the water supply strategy for the next 30 years. As a result of the move away from the use of fresh groundwater, a 17.5 MGD (66,200 m3/d) brackish-water desalination plant is under design for the City of Hialeah, Florida. Feedwater for this facility will be developed from the upper part of the Floridan Aquifer System at depths ranging from 1,080 to 1,480 ft (329–451 m) below surface. The initial water quality is mildly brackish with a total dissolved solids concentration (TDS) of about 2,300 mg/l. The anticipated volume of raw water required to operate the RO plant will be about 23.3 MGD (88,200 m3/d). The raw water will be obtained from 12 primary production wells and two backup capacity wells. A critical design issue for any RO plant is the maintenance of feedwater quality over the operating life-cycle of the facility. The wellfield water quality is anticipated to change in time because of the upward leakage of greater salinity w...

The potential future impact of climate warming and other human activities on the productive capacity of Canada’s lake fisheries: a meta-model

A simple meta-model was used to examine how climate warming and stresses due to other human activities might affect the productive capacity of fisheries in all of Canada’s lakes. Recent estimates of lake resource characteristics by secondary watershed and area size-class provided the basis for the model. Potential fishery productivity was estimated using a variant of the Schlesinger and Regier (1982) model which had lake mean depth, total dissolved solids concentration, and mean annual air temperature as inputs. A business-as-usual climate change scenario (SRES A2) was used to estimate worst case future temperature increases (4.5–8.3°C by the 2080s). The stress index from Chu et al. (2003) was used as a proxy for the impact on fisheries of other human activities. Projected populations for the SRES A2 scenario were used to scale future stress index levels. Potential biotic responses to warming were represented in two ways; the first as potential biotic displacement of currently dominant species when temperature rose beyond their preferred range and the second as potential biotic adaptation of other species, particularly in species rich areas, replacing displaced species. Potential productive capacity of fisheries in all Canadian lakes was 361,000 tonnes for the baseline climate norms period of 1961–1990. Climate warming increased productivity by 80.7% in the 2080s but stress reduced levels by 19.4% in the norms period and held the increase to 10.3% in the 2080s. Biotic displacement alone resulted in large decreases in productivity, by 65.2% in the 2080s and, when stress was added, by 79.5%. Biotic adaptation largely offset displacement. Applying stress and both biotic responses productivity was reduced by 31.4% in the 2080s from the unstressed norms baseline or 12% with stress added. Further investigations are needed to better establish the likely extent of stress impacts and potential biotic responses to climate warming in Canada’s lakes.

Stream Fish Community Responses to a Gradient of Specific Conductance

We assessed the impacts of a specific conductance gradient attributable to treated coal- mining discharges on the fish communities of a southwestern Pennsylvania stream. Total dissolved solids concentrations were determined from specific conductance values. A total of 10,940 fish representing seven families and 42 species/hybrids were collected from 17 stations over the entire survey. Species richness, density, and the coefficient of community loss (I) showed marked impairment at the two stations directly below the discharges and the downstream recovery was interrupted at one station by untreated discharges from a mine refuse pile. Species richness declined from 28 at the reference site to 7 at the station directly below the treated effluents. This study suggests that the threshold for in-stream conductivity impairment to fish communities in this region is in the range of 3,000-3,500 µS/cm and 2,000-2,300 mg/l of total dissolved solids, respectively.

Migration of Organic Contaminants from Landfill: Minimum Thickness of Barriers

Point sources such as landfills, can release high concentrations of contaminants into the groundwater because of migration of leachate from its bottom, which is generated primarily as a result of precipitation falling on an active land- fill surface, leaching out the potential organic and inorganic contaminants from landfilled waste and discharging the same to groundwater in underlying aquifer. Leachate from young landfills has high dissolved solids content as well as a high concentration of organic matter. Landfill leachate has the potential to contaminate the surrounding environment and im- pair groundwater use. Organic contaminants in landfill leachate originate from incoming wastes or are produced as a re- sult of biochemical reactions taking place in landfills. To protect the groundwater from contamination by landfill leachate, it is quite essential to provide the bottom barrier of suitable thickness, and to minimize the amount of water that could en- ter the landfill to create leachate. The present study was undertaken to determine the rate of movement of potential con- taminants from its bottom to the aquifer media, so as to evolve a rational method for the determination of thickness of bot- tom barrier on sound engineering practice, in place of adopting a prescriptive standard, which is very common in most of the Asian countries. The study was undertaken for non conservative contaminant Dissolved Organic Carbon (DOC). The governing equation of contaminant transport was solved using finite difference method, and finite mass boundary condi- tion to ape the finite mass of contaminants in a landfill. The solution of the model was run in MatLab 7.0 for a range of Darcy velocities and retardation factors for a representative equivalent height of leachate. Design curves were drawn which can be used for determination of suitable barrier thickness on the basis of expected maximum concentration of DOC in landfill leachate and maximum permissible concentration of the same.

Treatment of a denim producing textile industry wastewater using pilot-scale membrane bioreactor

The objective of this study was to investigate the performance of a pilot-scale membrane bioreactor (MBR) system for the treatment of a highly concentrated mixed wastewater from wet processes (dyeing, finishing, and sizing) of a denim producing textile industry. The MBR system, containing a submerged hollow fiber membrane module in the aeration tank, was operated aerobically for about 3 months on-site at a continuous flow mode. The system was operated at two different operation stages: (1) no sludge wastage with a typical permeate flux of 20 L/m 2 h and (2) a solids retention time of 25 days with the same flux. During the whole operation period, despite the high dissolved solids content in the influent, very high treatment efficiencies were achieved. The performance of the MBR system was not adversely affected by the variations in the influent characteristics, food/microorganism ratio, organic loading rate, and specific substrate utilization rate. The average values of some effluent quality parameters found in the entire operation period were color, 53 Pt Co; turbidity, 0.31 NTU; TSS, 0.6 mg/L; BOD 5, 15 mg/L; COD, 37 mg/L; NH 5N, 1.0 mg/L; NO 3N, 9.6 mg/L; and TN, 10.5 mg/L. Reduction in permeate flux due to membrane fouling was observed only once during all operation and such fouling was removed by applying chemical backwashing and chemical cleaning procedures. The results indicated that complex and highly polluted denim textile wastewaters could be treated very effectively by MBR systems. Color values from as high as 8100 Pt Co levels were significantly reduced to about 50 Pt Co levels, indicating that MBR effluent could be reused in the production processes.

High recovery of concentrated RO brines using forward osmosis and membrane distillation

Vacuum-enhanced direct contact membrane distillation (VEDCMD) and forward osmosis (FO) were investigated for water recovery enhancement in desalination of brackish water. Past studies have demonstrated that both VEDCMD and FO can be effectively utilized in the treatment of a wide range of highly concentrated feed solutions. In the current study, two reverse osmosis (RO) brine streams with total dissolved solids concentrations averaging 7500 and 17,500 mg/L were further desalinated by VEDCMD and by FO. In both processes, high water recoveries were achieved; however, recoveries were limited by precipitation of inorganic salts on the membrane surface. Various cleaning techniques were able to remove the scale layer from the membrane and restore water flux to almost initial levels. FO achieved water recoveries up to 90% from the brines and VEDCMD achieved water recoveries up to 81% from the brines. Addition of a scale inhibitor during both processes was effective at maintaining high water flux for extended time. When considering the total water recovery (the recovery from the RO processes combined with the batch recovery from the VEDCMD or FO process), greater than 96 and 98% total recoveries were achieved for the two different brine streams.

Salinity tolerance evaluation methodology for desalination plant discharge

Seawater desalination plants generate concentrate (brine) which typically has 1.5 to 2 times higher total dissolved solids concentration (salinity) than that of the ambient seawater. When returned to the ocean without dilution, this concentrate may have a negative impact on the aquatic environment in the area of the discharge. The environmental impact of the desalination plant discharge is very site-specific and depends to a great extent on the salinity tolerance of the specific marine organisms inhabiting the water column and benthic environment influenced by the discharge. This work presents methodology that allows establishing the site-specific maximum level of salinity concentration (salinity tolerance threshold) at which marine organisms not only survive, but can also grow and reproduce normally. The described method was used successfully for the permitting of the concentrate ocean discharge of two large seawater desalination projects in California — the 189,000 m3/d (50 MGD) Carlsbad and Huntington Beach desalination plants.

Impact of dyeing industrial effluents on the groundwater quality in Kancheepuram (India)

Dyeing and printing of textile being a traditional industry of Kancheepuram town, a good number of textile industries along with dyeing and printing clusters have come up in the area. The dyeing units in Kancheepuram municipality and the surrounding villages are under constant threat of ground water contamination with chemicals of dyes. The present study evaluates the groundwater quality in and around the Kancheepuram town of Tamil Nadu with reference to drinking and irrigation purposes. Twenty groundwater samples were collected from various parts of the dyeing industrial region and the samples were analysed with standard analytic methods. The concentrations of total dissolved solids (1138 to 2574 mg/L), chloride (216 to 847 mg/L), total hardness (225 to 760 mg/L), sulphate (64 to 536 mg/L), nitrate (up to 58 mg/L), iron (up to 2.3 mg/L) and lead (up to 0.281 mg/L) were found to be higher and exceeded the permissible limits of BIS and WHO standards. The user specific water quality indices (USWQI) of each groundwater sample were evaluated for both purposes. The USWQI of the groundwater samples varied from 85 to 30 for drinking purpose and 89 to 50 for irrigation purpose. The results show that, the groundwater quality in the present study area can be categorized under 'good' for irrigation purpose and 'fair' for drinking purpose. Access to safe drinking water supply is one of the basic needs of society and hence a comprehensive plan of action is sought to curb groundwater contamination in the studied region.

The natural radioactivity in water by gross alpha and beta measurements

An alternative method for evaluating gross alpha and beta radioactivity in water was developed by performing alpha counting using a surface barrier detector and gamma- ray spectrometry using a NaI(Tl) scintillation detector. Several experiments were realized under controlled conditions in the laboratory with the aim of establishing adequate calibration of the systems utilized for performing activity concentration measurements in water samples of variable salinity. Groundwater samples collected at several spas in São Paulo and Minas Gerais States in Brazil were submitted to the developed technique in order to assure its applicability in waters characterized by different Total Dissolved Solids content. The values obtained were compatible with the previous knowledge of the radioactivity of the studied water sources, thus indicating the reliability and usefulness of the method for generating information on investigations focusing environmental aspects and/or the evaluation of the drinking water quality in terms of radiological aspects.