Ratio Of Bicarbonate Research Articles

The Δ Anion Gap/Δ Bicarbonate Ratio in Lactic Acidosis: Time for a New Baseline?

The ratio of delta anion gap and delta bicarbonate (ΔAG/ΔHCO3) is used to detect co-existing acid-base disorders in patients with high anion gap metabolic acidosis. The ΔAG/ΔHCO3 ratio of 1.6-1.8:1 in lactic acidosis is derived from limited data using mean normal values for AG and serum HCO3. The objective of this study was to be the first to examine the ΔAG/ΔHCO3 using each patient's individual baseline AG and serum HCO3. This was a retrospective cohort study of adult ICU patients with sepsis. Lab data from simultaneously drawn chemistry panel, including anion gap and serum lactate on admission to the ICU was obtained. Baseline AG, HCO3 and albumin measurements were obtained 1-24 months prior to ICU admission. The ΔAG/ΔHCO3 was calculated using an albumin-corrected anion gap and each patient's individual baseline AG and serum HCO3. 344 patients were included. 128 patients had normal serum lactate levels (≤1.9 mmol/L) and 216 patients had elevated serum lactate levels (>1.9 mmol/L). ΔAG/ΔHCO3 was calculated for the 216 patients who had elevated serum lactate levels (>1.9 mmol/L). The mean ΔAG/ΔHCO3 for all patients with elevated serum lactate levels was 1.20 (SD 1.50). The mean ΔAG/ΔHCO3 calculated using an albumin-corrected anion gap and each patient's individual baseline AG and serum HCO3 was 1.20. The ΔAG/ΔHCO3 reported in prior literature which used mean normal AG and serum HCO3 was 1.6-1.8, highlighting that use of mean normal values affects the calculation of the ΔAG/ΔHCO3 and subsequent conclusions about underlying pathophysiology. The use of these mean normal values can result in misdiagnosis of complex acid-base disorders and inappropriate treatment. Our analysis indicates that the elevated ΔAG/ΔHCO3 is likely due to unmeasured anions contributing to an elevation in AG.

Multi-parametric hyperpolarized 13C/1H imaging reveals Warburg-related metabolic dysfunction and associated regional heterogeneity in high-grade human gliomas

BackgroundDynamic hyperpolarized (HP)-13C MRI has enabled real-time, non-invasive assessment of Warburg-related metabolic dysregulation in glioma using a [1-13C]pyruvate tracer that undergoes conversion to [1-13C]lactate and [13C]bicarbonate. Using a multi-parametric 1H/HP-13C imaging approach, we investigated dynamic and steady-state metabolism, together with physiological parameters, in high-grade gliomas to characterize active tumor. MethodsMulti-parametric 1H/HP-13C MRI data were acquired from fifteen patients with progressive/treatment-naïve glioblastoma [prog/TN GBM, IDH-wildtype (n = 11)], progressive astrocytoma, IDH-mutant, grade 4 (G4AIDH+, n = 2) and GBM manifesting treatment effects (n = 2). Voxel-wise regional analysis of the cohort with prog/TN GBM assessed imaging heterogeneity across contrast-enhancing/non-enhancing lesions (CEL/NEL) and normal-appearing white matter (NAWM) using a mixed effects model. To enable cross-nucleus parameter association, normalized perfusion, diffusion, and dynamic/steady-state (HP-13C/spectroscopic) metabolic data were collectively examined at the 13C resolution. Prog/TN GBM were similarly compared against progressive G4AIDH+ and treatment effects. ResultsRegional analysis of Prog/TN GBM metabolism revealed statistically significant heterogeneity in 1H choline-to-N-acetylaspartate index (CNI)max, [1-13C]lactate, modified [1-13C]lactate-to-[1-13C]pyruvate ratio (CELval > NELval > NAWMval); [1-13C]lactate-to-[13C]bicarbonate ratio (CELval > NELval/NAWMval); and 1H-lactate (CELval/NELval > NAWMundetected). Significant associations were found between normalized perfusion (cerebral blood volume, nCBV; peak height, nPH) and levels of [1-13C]pyruvate and [1-13C]lactate, as well as between CNImax and levels of [1-13C]pyruvate, [1-13C]lactate and modified ratio. GBM, by comparison to G4AIDH+, displayed lower perfusion %-recovery and modeled rate constants for [1-13C]pyruvate-to-[1-13C]lactate conversion (kPL), and higher 1H-lactate and [1-13C]pyruvate levels, while having higher nCBV, %-recovery, kPL, [1-13C]pyruvate-to-[1-13C]lactate and modified ratios relative to treatment effects. ConclusionsGBM consistently displayed aberrant, Warburg-related metabolism and regional heterogeneity detectable by novel HP-13C/1H imaging techniques.

Degree of Dissolution of Nickel(II) Hydroxide in Mixtures of Aqueous Solutions of Ammonia and Ammonium Bicarbonate

The degree of dissolution of nickel(II) hydroxide in mixtures of aqueous solutions of ammonia and ammonium bicarbonate has been studied. The equilibrium between the solid and liquid phases was reached in 11–12 h after the start of experiment. Nickel(II) hydroxide showed higher solubility in the ammonia–carbonate mixture compared with aqueous solutions of ammonia and ammonium bicarbonate. The ratio of ammonium bicarbonate and ammonia concentrations in solution at which the highest degree of dissolution of Ni(OH)2 was achieved was determined. An analytical description of the ion-molecular equilibrium in the ammonia– carbonate mixture was given, and the equilibrium concentrations of molecules and ions in the system were calculated. A stoichiometric equation describing the dissolution of nickel(II) hydroxide in an ammonia–carbonate solution was given.

Spatial variability and risk assessment of metals in groundwater of district Kamber-Shahdadkot, Sindh, Pakistan

The study examined the groundwater quality of agricultural based area Nasirabad, Warah and Miro Khan talukas of district Kamber-Shahdadkot. Representative 46 samples were collected commonly used for drinking purposes and analyzed for 25 different quality parameters by using standard analytical procedures. The GIS interpolation tools were used to exhibit the spatial variation of groundwater parameters, for drinking as well as irrigation in the study area. The values of EC and TDS varied from 569 to 17790 μS/cm and 364–11385 mg/L respectively. The results of anions varied HCO3− from 140 to 460, Cl− 21 to 4545 and SO42− 28 to 2050 mg/L and results of cations varied from Na+ 20 to 1380, K+ 03 to 143, Ca2+ 32 to 1302 and Mg2+ 15–728 mg/L. Results of heavy metals varied from Pb 0–44 μg/L, Co 3.9 to 63.8, Cu 0 to 3.9 to 63.8, Fe 10.1 to 335, Cr 0 to 134, Ni 0 to 152, Mn 0 to 140 and Cd 0–29.4 μg/L. The fluoride value of 80.44% samples were above the allowable limits for drinking. The water quality index (WQI) results showed that 70% samples were in poor to unfit water categories. The contaminated index showed 47.82% samples with higher Cd values than 3. The chronic daily intake (CDI) and hazards quotient indices (HQ) were also calculated and HQ did not indicate possible hazourds effects on human health. The samples were examined for principal component analysis, Gibb's diagrams, contour diagrams, scatter diagrams, correlation matrix, Piper diagrams and cluster analysis. The Piper plots showed Na+-Cl-, Ca2+-Mg2+-HCO3- and Ca2+-Mg2+-Cl- species and Gibbs diagrams showed rock and evaporation dominancy. The scatter plots were used to know the hydrochemistry of the area like ion exchange and weathering processes. The quality of water was examined for agriculture, based on chloride bicarbonate ratio, sodium percentage, salinity hazard, Kelly's index, chloro alkaline indices I, chloride-sulphate ratio, residual sodium carbonate, sodium adsorption ratio and permeability index. The results showed that 44–80% samples were fit for irrigation purposes depending upon the requirement of agriculture.

The development of Moringa leaves effervescent granules with effervescent agent of citric acid and sodium bicarbonate

Moringa leaves are part of Moringa Oleifera, which have a high antioxidant content, therefore, it is beneficial for overcoming free radicals in the body. Furthermore, the leaves contents have the potential to be developed into a functional drink in the form of effervescent granules. The important aspects influencing the physical characteristics, stability, and acceptability of granule is the type and ratio of the effervescent agent. In this study, citric acid and sodium bicarbonate were used as effervescent agents because they both provide acceptable texture and mouthfeel. This study aimed to develop an effervescent granule formula of Moringa leaves and to optimize the molar ratio of citric acid and sodium bicarbonate as the effervescent agent. Three molar ratios of citric acid and sodium bicarbonate were optimized, namely 1:3.11 (Formulation 1), 1:3 (Formulation 2), and 1:2.93 (Formulation 3). These formulations were developed using the wet granulation method. The results showed effervescent granules of the three formulations exhibited good flowability and uniform particle size distribution. Furthermore, formulation 3 showed better granule flow characteristics than the others. The results after reconstitution showed the granules were quickly dispersed within 207-234 secs, the pH of the preparation ranged between 5.74-5.92 (neutral pH), the viscosity was between 326-333 cps, and exhibited dilatant flow characteristics. Also, the organoleptic and sensory evaluation results showed formulation 3 was the most acceptable in terms of color, taste, aroma, and texture. Based on these findings, it was concluded that formulation 3 which used (citric acid ratio, sodium bicarbonate 1:2.93) was the optimal formulation.

Structural and antioxidant properties of guanylhydrazinium pyrazine-2-carboxylate

In general, molecules with certain functional groups such as amine (-NH2) and carboxyl (-COOH) can promote the growth of co-crystals leading to the formation of supramolecular networks. However, if the differences in the pKa values of the two molecules are large [pKa (base)—pKa (acid)], salts can result instead of ‘real’ co-crystals. Here, we report the formation of such salt by letting pyrazine-2-carboxylic acid (pKa = 2.9) crystallize together with aminoguanidine (pKa = 11.5; high Δpka = 8.6) a nitrogen-rich organic base. The title salt has been prepared by slow evaporation of an equimolar ratio of guanylhydrazine bicarbonate (i.e., aminoguanidine bicarbonate (AgunH.HCO3)) and pyrazine-2-carboxylic acid (Pymca) in aqueous medium. The salt was characterized by IR spectroscopy, powder and single-crystal X-ray diffraction techniques. This material shows enhanced antioxidant activity and this is due to the crucial role of hydrazinic moiety in the aminoguanidinium salt.

A gas-free electrodialytic pH modifier for ion chromatography

We for the first time describe a gas-free electrodialytic pH modifier deployed at the pump outlet side to manipulate carbonate eluent used for ion chromatography (IC). It is in sandwich configured, in which the central eluent channel is spatially isolated from two outer regenerant chambers by a stacked cation exchange membranes (sCEM) and a bipolar membrane (BPM) plus a stacked anion exchange membranes (sAEM) (BPM-sAEM), the cation exchange side of BPM is facing the central channel (the cathode direction). One electrode is put in each regenerant chamber and the sCEM side is cathode with respect to the anode of BPM-sAEM side. When a potassium carbonate eluent is pumped into the central channel and a DC current is applied, a controlled amount of potassium ions will be removed by migrating across sCEM into cathodic chamber. Meanwhile, hydronium ions generated from enhanced water splitting at the intermediate layer of BPM will electromigrate into central channel to form bicarbonate. By controlling the current, the potassium carbonate eluent can be manipulated to obtain a mixed eluent with different ratio of carbonate and bicarbonate. At least 10 mM K2CO3 eluent can be online changed modified into 10 mM KHCO3 with near-ideal Faradaic efficiency (∼92%). The device demonstrated good reproducibility, as indicated by retention time of relative standard deviation (RSD) < 0.43% and the peak area of RSD <0.93%.

The effect of sodium bicarbonate ratio for the mechanical properties of underarm pads rubber for crutches

Research on the effect of the ratio of sodium bicarbonate on the mechanical properties of underarm crutch pads from natural rubber SIR-20 has been carried out. The ratio of sodium bicarbonate used was 1.00 phr; 1.50 phr; 2.00 phr; and 2.50 phr. The rubber compound for underarm crutch pads was made by the compounding process using an open rubber mixing mill and vulcanization at a temperature of 120 °C for 11 minutes. The best formula for curing characteristic rheometer test results at a temperature of 150 °C was URC-04 with Smax = 4.95 kg/cm, Smin = 0.44 kg/cm, ΔS = 4.51 kg/cm, t90 = 6.57 min and ts2 = 4.13 min. The mechanical test result showed the hardness test before aging and after aging of 31 Shore A, and 32 shore A, tear strength of 8.50 kN/m, elongation at the break before aging and after aging of 300%. The results of the identification of functional groups by FTIR for infrared absorption in each sample generally showed the same pattern with one another. SEM analysis result showed the distribution of materials and the formation of pores by sodium bicarbonate was not evenly distributed with an average diameter of 5 microns.

Investigation on an electrochemical pilot equipment for water softening with an automatic descaling system: Parameter optimization and energy consumption analysis

Electrochemical water softening (EWS) technology is considered to be a very promising descaling method due to its superiorities in clean, efficient and water-saving ability, although limited by the cleaning of cathode scale. Herein, an innovative EWS device coupled with an automatic descaling module was manufactured and applied to treat the industrial recirculating cooling water (RCW). Response surface methodology (RSM) analysis based on Box–Behnken design (BBD) was applied to optimize the combination effect of four important operation parameters, including initial hardness (1150 mg/L, as Ca2+), ratio of hardness and bicarbonate (0.5), current density (30 A/m2) and circulating water flow (20 m3/h). Next, a mathematical dynamic model was employed to reveal the relationship between the hardness removal percentage and the current density (ρ, A/m2) according to the RSM analysis results. Additionally, various configurations of the device were performed and demonstrated that the integration of automatic descaling system enabled a significant improvement on the descaling capacity (19.95 g/h/m2) and energy consumptions (27.1 kW h/kg CaCO3), which exhibited evident economic and environmental advantages compared to the chemical scale inhibitor method. This work provides a facile strategy for the development and industrial applications of EWS technology.

Four-factor optimization for PET glycolysis with consideration of the effect of sodium bicarbonate catalyst using response surface methodology

In this study, Response Surface Methodology based on four-factor Box-Behnken design was applied to suggest the optimal conditions for glycolysis of polyethylene terephthalate (PET) and to analyze the individual and interaction effects of the factors on the process. Four independent factors of interest, namely reaction time (3–5 h), reaction temperature (192–200 °C), mass ratio of ethylene glycol (EG) to PET (2.5–7.5), and mass ratio of sodium bicarbonate (NaHCO3) to PET (0.6–1.0%), were under consideration for their catalyst effect on the process. A regression model as a mathematical function of the four factors was obtained to predict the yield of bis(2-hydroxyethyl) terephthalate (BHET) yield and its reliability was evaluated by analysis of variance. A remarkably high yield of 75.7% was obtained with 1.3% error from the predicted value at the optimal operating conditions for temperature, time, EG:PET mass ratio, and NaHCO3:PET mass ratio of 192 °C, 3.02 h, 6.09 and 0.82%, respectively. The experimental results and analysis of response surfaces revealed that an inappropriately large amount of catalyst might restrict monomer conversion under excess EG conditions. Moreover, PET glycolysis process could be carried out under lower temperature and shorter time due to the profound effect of excess EG at a suitable concentration level of NaHCO3. This suggested future in-depth analysis with wider parameter space to optimize PET glycolysis under conditions of large amount of EG and to gain insight into the interaction effect between EG amount and catalyst concentration.

CO2 Measurement of Synthetic Biogas by Passing It through Dilute NaOH Solution

The feasibility of measuring CO2 content in biogas was evaluated in this research. Firstly, Curtipot pH simulator was used to visualize the titration behaviors of various percentages of dissolved CO2 in a wide range of concentrations of NaOH solution. As a general output of those simulations, it was shown that when the titration curves of different CO2 content samples are separated enough, titration can provide precise information about the value of dissolved CO2. Also, when the ratio of the molar concentration of NaOH to the molar concentration of CO2 is in the range of 1 to 2(equivalent to the stoichiometric ratio of bicarbonate and carbonate), the separability of the curves is enough satisfactory to be used for precise determination of CO2; Outside this range, the accuracy of data segregation by titration diminishes. Moreover, when the ratio of the molar concentration of NaOH to CO2 is between 1 and 2, by only a one-time probing, it is possible to determine the concentration of CO2 in the standard NaOH solution. In this case, titration over a wide range of pH does not provide more reliable and accurate information. The effects of temperature CO2 measurement shows that a difference of even 10 °C can only cause less than 1% decrease in CO2 estimation. Finally, a comparison between gas chromatography and pH measurement was performed and the experimental results showed closeness the results of our proposed method with that of GC(less than 0.05% relative error). This method can be used in designing a non-expensive measuring method that would pave down the road for developing countries.

Assessment of Seawater Intrusion into Shallow Coastal Aquifer in Kanyakumari District, Tamilnadu, India

Improved use of groundwater is often causing intrusion of seawater. The intrusion of seawater also takes place in coastal areas. In this analysis, the distribution and the levels of intrusion in the research area (Kanyakumari district, Tamilnadu, India) are determined. The test was done using random samples at a period of 15 days in which 30 different samples were taken in 5 different locations with a certain distance from the seashore, then chemical analysis including pH, electrical conductivity (EC), total dissolved solids (TDS), chloride, sodium, calcium, magnesium, carbonate, and bicarbonate water quality parameters were carried out. Chloride Bicarbonate Ratio was used for the calculation of the penetration rate of the seawater, and subsequently chloride and electric conductivity were defined as type and quality of water characters. The results showed that the shallow aquifer was intruded by seawater at several sample levels, which was included in the normal to high intrusion classification. The sea water intrusion was classified as freshwater to saltwater, the concentrations in chloride ranged from 159 to 6021 mg / L. The ratio of bicarbonate chloride was 0.28 to 21.46, normally above 15.5, indicating that groundwater was disturbed. As a result, in comparison to standards or other seawater intrusion indicators, Rajakamangalam-well 1 (RM-W1) has been affected by seawater intrusion highly.

Characterization of Physical and Chemical Properties of Effervescent Tablets Temulawak (Curcuma zanthorrhiza) in the Various Proportion of Sodium Bicarbonate and Tartaric Acid

The purpose of this study was to determine the effect of comparative treatment of the proportion of Sodium bicarbonate and tartaric acid on the physical and chemical properties of effervescent tablets temulawak, as well as knowing the proportions of sodium bicarbonate and tartaric acid right to produce a good effervescent tablets temulawak. The research method uses a single completely randomized design namely the ratio of sodium bicarbonate: tartaric acid, (F1 = 2.0: 2.5; F2 = 2.5: 2.0; F3 = 3.0; 1.3; F4 = 3 , 5: 1,0, and F5 = 4.0: 0.5y). each treatment was repeated 3 (three) times. The resulted data were analyzed by ANOVA test. The results showed that the proportion of sodium bicarbonate and tartaric acid significantly affected color lightness, hardness, hygroscopicity, solubility times, water content, ash content, and not significantly affect viscosity and pH. The right proportion of sodium bicarbonate acid tartaric acid for making effervescent tablets temulawak is A1 treatment (proportion of sodium bicarbonate and tartaric acid 2.0: 2.5) with the attributes of water content of 66.72%, hardness of 2.20 kg, hygroscopicity of 25.43 g, solubility times of 35 seconds, viscosity 1.75 MPa.S, water content 1.19%, ash content 3.10%, and pH = 5.1.

Selective Leaching for Uranium and Gold from their Bearing Sedimentary Lower Carbonaceous Sandstone Rocks, Southwestern Sinai, Egypt

Uranium as a nuclear element with strategic importance and gold as one of the important economic precious metals made their selective leaching from the sedimentary lower carbonaceous sandstone rocks, Southwestern Sinai, Egypt with economic concentrations (5ppm gold and 160 ppm uranium), an important issue for facilitating either their accurate determination or highest percentage recovery. A sequential leaching of uranium followed by gold was proposed in this work after studying individually their optimized leaching conditions. From the latter; a lixiviant mixture of sample to sodium carbonate ratio 1:1, sample to sodium bicarbonate ratio 1:1 together with sodium thiosulphate, as oxidant, 0.5g was used for the selective leaching of uranium. On the other hand, a leaching reagent mixture of 5% (w/v) from each of potassium cyanide, sodium thiosulphate and 10 ml from 30% hydrogen peroxide was used for the selective leaching of gold where several factors were optimized; concentration of individual component in each lixiviant, agitation time, solid to liquid ratio, temperature and pH. A percentage leaching of 97% and 96% for uranium and gold respectively were reached. Uranium was selectively separated using Amberlite IRA 402 Cl resin ion exchange resin with 99.5 % percentage recovery. The recovery of gold needs a large bulk weight from the sample due to its relatively low concentration.

Reversed metabolic reprogramming as a measure of cancer treatment efficacy in rat C6 glioma model.

BackgroundMetabolism in tumor shifts from oxidative phosphorylation to inefficient glycolysis resulting in overproduction of lactate (Warburg effect), and cancers may be effectively treated if this imbalance were corrected. The aim of this longitudinal study of glioblastoma in a rat model was to determine whether the ratio of lactate (surrogate marker for glycolysis) to bicarbonate (for oxidative phosphorylation), as measured via in vivo magnetic resonance imaging of hyperpolarized 13C-labeled pyruvate accurately predicts survival.MethodsC6 Glioma implanted male Wistar rats (N = 26) were treated with an anti-vascular endothelial growth factor antibody B20.4.1.1 in a preliminary study to assess the efficacy of the drug. In a subsequent longitudinal survival study, magnetic resonance spectroscopic imaging (MRSI) was used to estimate [1-13C]Lactate and [1-13C]Bicarbonate in tumor and contralateral normal appearing brain of glioma implanted rats (N = 13) after injection of hyperpolarized [1-13C]Pyruvate at baseline and 48 hours post-treatment with B20.4.1.1.ResultsA survival of ~25% of B20.4.1.1 treated rats was noted in the preliminary study. In the longitudinal imaging experiment, changes in 13C Lactate, 13C Bicarbonate and tumor size measured at baseline and 48 hours post-treatment did not correlate with survival. 13C Lactate to 13C Bicarbonate ratio increased in all the 6 animals that succumbed to the tumor whereas the ratio decreased in 6 of the 7 animals that survived past the 70-day observation period.Conclusions13C Lactate to 13C Bicarbonate ratio (Lac/Bic) at 48 hours post-treatment is highly predictive of survival (p = 0.003). These results suggest a potential role for the 13C Lac/Bic ratio serving as a valuable measure of tumor metabolism and predicting therapeutic response.

Groundwater quality assessment of Shahdadkot, Qubo Saeed Khan and Sijawal Junejo Talukas of District Qambar Shahdadkot, Sindh

The study examines the water quality of Shahdadkot, Qubo Saeed Khan and Sijawal Junejo talukas of Qambar Shahdadkot District, less affected by industrial contamination. A total of 38 groundwater samples were collected and analysed for 28 parameters. The results indicated that 57.89% samples were not suitable for drinking purpose with total dissolved solids above than maximum permissible limit of World Health Organization (WHO) (1000 mg/L). The pH, total phosphate, orthophosphate and nitrite were within WHO limits. The concentration of essential metals more than half samples, fluoride in 60.52% and heavy metals 0–50% were contaminated higher than permissible limits of WHO. The statistical analysis of water quality parameters was also carried out to evaluate coefficient of determination among the parameters, cluster analysis and principal component analysis. Water quality determined for irrigation based on Kelly index (KI), sodium percentage (Na%), chloride–sulphate ratio, sodium adsorption ratio, permeability index (PI), chloroalkaline indices 1 (CAI-1), residual sodium carbonate and chloride bicarbonate ratio indicated that samples (55 to 100%) could be used for irrigation purposes. The consumption of water with high concentration of salts and fluoride above the permissible limits may be a cause of a number of diseases in the area.

The effect of citric acid and sodium bicarbonate concentration on the quality of effervescent of red ginger extract

The effervescent product of red ginger extract was made from a mixture of red ginger extract, citric acid, sodium bicarbonate, dextrose, mannitol, sucralose and polyethylene glycol. This study used a single factor randomized complete design method with the ratio of different concentrations of citric acid and sodium bicarbonate (50:50, 51:49, 52:48, 53:47, 55:45) in three replication. Analysis of Variance (ANOVA) was used to see the effect of each treatment, if there was an effect of each treatment then continued with DMRT (Duncan Multiple Range Test) to see which levels produced differences in quality. The results showed that the addition of different concentrations of citric acid and sodium bicarbonate had significant effect (sig <α=0.01) on the value of soluble and effervescent pH of red ginger extract and significantly affected the level of color preference, taste and effervescent solubility of red ginger extract. The best effervescent product of red ginger extract was selected based on the hedonic test with the ratio of citric acid and sodium bicarbonate 52:48 with the following quality test results: 0.00% ethanol residue; levels of active red ginger 0.65%; and the level of effervescent red ginger extract 0.52%.

Re-mineralization of desalinated water using a mixture of CO2 and H2SO4

The corrosive tendency of desalinated water is commonly controlled by dosing acid to water flowing through a packed bed of limestone as to make it slightly supersaturated with respect to calcium carbonate. Acidification is achieved by dosage of either carbonic acid or sulfuric acid. Design models for re-mineralization in packed bed contactors are well established. Reduction of the carbon dioxide consumption required for re-mineralization, may be achieved by partial replacement with sulfuric acid, while maintaining the regulation stipulating a ratio of 1.3 to 2.0 between the equivalent alkalinity and calcium concentrations. The objective of this work was to extend the established kinetic model based on a single acid dissolution to the case of dissolution by a mixture of carbon dioxide and sulfuric acid. The derived model predicts the molar ratio of bicarbonate to calcium, in the product water, as a function of the molar ratio between the two acids. Experimental and predicted dissolution profiles are shown to be in very good agreement.

Risk assessment of heavy metals and salts for human and irrigation consumption of groundwater in Qambar city: a case study

ABSTRACTThe study investigated the water quality of groundwater for consumption of human beings and irrigation of taluka Qamber district Qamber-Shahdadkot, Sindh, Pakistan. A total of 21 representative groundwater samples were collected mostly used for human consumption. According to the research work, 81% samples were not suitable for drinking purpose with TDS above the maximum permissible limit of WHO (1000 mg/L). The pH, total phosphate-P, orth ophosphate-P, nitrate-N, nitrite-N, and arsenic were within WHO limits. The concentrations of essential metals more than half samples were higher than WHO guideline. The concentrations of trace metals like Mn, Fe, Co, and Cu of all samples were within WHO limits, but the values of Cr and Ni 52.38%, Cd 57.14%, and Pb 28.57% were above the WHO limits. The concentrations of fluoride in 81% were higher than permissible limits of WHO. The high consumption of water with concentration of salts and fluoride above the permissible limits may be a leading factor of a number of diseases in the area.The water quality determined for irrigation based on Kelly index (KI), sodium percentage (Na%), chloride–sulfate ratio, sodium adsorption ratio (SAR), permeability index (PI), chloro alkaline indices1 (CAI-1), residual sodium carbonate (RSC), and chloride bicarbonate ratio indicated that 25–90% samples were suitable for irrigation purposes.

Determining sea water intrusion in shallow aquifer using Chloride Bicarbonate Ratio Method

Increasing usage of ground water tends to cause sea water intrusion. Sea water intrusion often happens in coastal areas. This study was conducted to determine the spread, levels of intrusion and factors that affect sea water intrusion in the research area. The sampling technique was carried out using interval random sampling, where 30 samples were taken with a distance of 2 km each, and then chemical analysis was carried out including the parameters of Cl−, HCO3−, CO3=, and electrical conductivity (EC). The method used to determine the level of seawater intrusion was the method of Chloride Bicarbonate Ratio and then the types of water were classified based on chloride content and electrical conductivity. The determination of the distribution of seawater intrusion was done by mapping analysis using the ArcGis application program. To determine the factors that affected sea water intrusion, multivariate regression analysis with the “backward elimination” method was used. The results showed that on several sample points the shallow aquifer had been intruded by sea water with a ratio of 1.02 to 102.16 which were included in the category of intrusion of slightly to high. Chloride concentrations ranged from 2 mg/L to 31,160 mg/L and were classified as fresh water to salt water. Electrical conductivity ranged from 186 μmhos/cm to 26,400 μmhos/cm and generally above 200 μmhos/cm which meant that the sea water had been disturbed. Factors that significantly affected sea water intrusion were water usage debit and aquifer permeability with an adjusted coefficient R2 of 0.797.