Soda Production Research Articles

Study of the concordance between various concrete deformation models and experimental data for uniaxial compression cases

There are various equations describing concrete stress-strain curves, each yielding different theoretical curves. An important scientific question is achieving the best correspondence to experimental data. The Geniyev theory inherently includes equations for three components of stress and strain. In contrast, the Eurocode and the Russian Building Code equations are provided for uniaxial stress conditions. This paper presents a comparison of theoretical curves for uniaxial compression based on Eurocode equations, the Russian Building Code, and Geniyev theory with experimental results from tests on prism and cube samples. The analysis includes deviations of the maximum stress points of theoretical curves from the corresponding experimental data. Numerical analysis is provided for both stresses and strains. A distinguishing feature of this work compared to existing research on Geniyev theory equations is that they are presented in a resolute form, incorporating three parameters: concrete compressive strength, tensile strength, and the initial modulus of elasticity. The importance of using secondary resources on the basis of industrial waste is understood by both governments of developed countries and business (production of Portland cement using ground metallurgical slag as a mineral additive at Novotroitsk, Magnitogorsk, Sterlitamak, Katav-Ivanovsk and other plants in the South Urals). The use of secondary raw materials requires the creation of technological infrastructure for processing of secondary raw materials, the costs of which can be quickly recouped due to the cheapness and availability of industrial secondary raw materials and freeing the territory from environmental pollution. In order to recoup the costs of the infrastructure, it is necessary to guarantee full compliance of the quality of pavement elements with the requirements of GOST R 59120-2021. Secondary raw materials have a great variety and laboratory analysis of the quality of pavement elements is required in order to design compositions with the best quality, satisfying all regulatory requirements. In our work the authors present the results of laboratory research and evaluation of the possibility of using clinker-free lime-slag binder based on the mineral product of soda production and metallurgical slags to strengthen and stabilize soils for their use in pavement structures in the construction of roads for various purposes and climatic zones. It is experimentally shown that the addition of lime-slag binder in the amount of 8-10% of the dry weight of both cohesive (loamy soil, loamy sand) and non-cohesive (fine sand) soil allows to obtain reinforced soil with improved strength and elastic-deformative characteristics, which can be used instead of scarce natural crushed stone and gravel in the construction of underlying layers of pavements in the construction and reconstruction of highways. This technology can be used not only in the Russian Federation, but also in a number of other countries, including those with hot dry climates (e.g., the Republic of Egypt).

Analysis of the effectiveness of organic compounds from the amine group in precipitating ions from soda production wastewater

Treating wastewater from the soda industry is a complicated and lengthy process, requiring a great deal of labor and financial resources. No method has yet been developed to eliminate the environmental damage caused by the soda industry entirely. The leakage of highly contaminated soda production wastewater into soils, groundwater, and surface water can cause corrosion of water infrastructure and deterioration of water quality for both drinking and agricultural use. Soil contamination from post-production wastewater leads to erosion and adversely affects vegetation. The work focused on the removal of chloride, sulfate, calcium, and sodium from soda production wastewater by precipitation using organic solvents such as isopropylamine (IPA), diisopropylamine (DIPA), propylamine (PA) and ethylamine (EA) in various proportions. Statistical modelling through Bayesian beta regression was used to select the amine most effectively removing the tested ions in precipitate form. The effect of precipitating agent dosage on the pH and conductivity of the solution was also investigated. Samples of wastewater obtained from the soda industry were characterized by high values of pH (up to 11.9), specific electrolytic conductivity (up to 128 mS cm−1), and high concentrations of sodium (up to 13 g L−1), chloride (up to 60 g L−1) and calcium (up to 24 g L−1) ions. Solvent-based precipitation showed that organic solvents are effective in precipitating salts from wastewater from the soda industry. Sulfate and chloride removal efficiencies of 85.1 and 34 %, respectively, were observed. Statistical analysis showed that isopropylamine was the most effective amine for ion removal.

Towards a more sustainable hydrogen energy production: evaluating the use of different sources of water for chloralkaline electrolyzers

Water scarcity is becoming a serious threat for the implementation of energy storage devices based on hydrogen in the inland of dry regions, because of the difficulties in finding appropriate sources of water and the important environmental problem associated with the discharge of rejection saline streams produced during the purification of water. This becomes an opportunity for chloralkaline technology in which the quality of water used is lower than the required in other hydrogen production technologies. This work compares the performance of chloralkaline electrolyzers fed with different solutions of NaCl (from brackish water to brines) with that obtained feeding two natural water samples (seawater and porewater) and three processed waters (rejections streams of the electrodialysis, reverse osmosis of the porewater and a real rejection of the reverse osmosis of a vineyard). All tests were made with a lab-scale 3-D printed cell where, in addition, the performance of Ti/RuO2 and Pb/PbO2 anodes were compared, being always better the results obtained in the tests made with the Ti/RuO2 electrode. Results obtained indicate that efficiencies reached using these alternative sources are lower than those which can be reached using synthetic brines that, in turn, were very near to the standards reached in the chloralkaline industry. In the case of hydrogen production, the maximum values were obtained for seawater, reaching efficiencies proximate to 8.0 mg H2 (Wh)-1. Rejection streams of desalination processes were found to be less efficient, attaining values in the range 2 and 4 mg H2 (Wh)-1. Regarding the production of chlorine and caustic soda, better performances were reached again with seawater (161.7 mg Cl2 (Wh)-1 and 0.092 mg OH- (Wh)-1 ) and with the rejection of the electrodialysis, which also reached sound values of 90.4 mg Cl2 (Wh)-1 and 0.107 mg OH- (Wh)-1. Results obtained are promising and indicate a path that must be further worked for the implementation of a greener water management strategy in the hydrogen -based energy storage technology.

Evaluation of Consumers’ Behaviour on Brand Loyaltyand Switching of Competitive Soda Products

This study examines the brand loyalty principle in three (3) bottling soda drinks on the basis of consumers’ choice based on cost, product quality and availability determinant factors. The data collected from respondents through a questionnaire were analyzed on the basis of ChapmanKolmogorov transition probability matrix for Markov processes for 1st ,2nd and 3rd steps.. The results revealed varying retention and switching patterns as both the upward and downward diagonals decreases as the step increases though Pepsi has the highest retention likelihood under cost and product quality determinant factors with a differential margin of about 14% to Coke while Limca takes the least. Pepsi maintains a margin of close to 30% ahead of Coke while Limca assumes the least under consumers’ choice based on product quality. The retention is higher in Coke based on availability with a margin of approximately 8% to Pepsi which is 4% higher than Limca.It was also observed that probability of switching from Pepsi to coke is higher than switching to Limca at the various steps under all the choice determinants factors. The computation of the markets share for the brands based on the initial probabilities under choice determinants factors revealed Pepsi as the dominant brand under cost and product quality considerations while Coke dominates under availability factor while Limca constantly maintains the rare both in terms of the retention and switching as well as market shares

Investigation of the Effect of Membrane Type on Ammonia Formation and HCl Formation from Ammonium Chloride and Sodium Chloride in Two-Compartment Bipolar Membrane Electrodialysis

One of the most important environmental problems of the Solvay process, which is one of the synthetic soda production processes, is the liquid and solid wastes generated by the distillation unit. This study investigates the effect of membrane type on the formation of ammonia (NH3) and Hydrochloric acid (HCI) in a two-compartment bipolar membrane electrodialysis (BMED) system. The BMED process was evaluated as a potential replacement for the distillation unit in synthetic soda production, specifically focusing on the impact of different membranes on NH3 and HCI formation. Disposal of distillation waste directly into the environment without any treatment can cause serious ecological problems in the long term. Bipolar membranes (BM) and anion exchange membranes (AEM) were utilized in this study in which the BMED cell was designed as a two-compartment, three-repeat design. The experiments were carried out by keeping the current/voltage values (14V/4.8 A) constant in the system using direct current (DC). Two different commercial membrane types, FumaTech and PCCell, were used as parameters in the study. The initial feed concentrations were kept constant and the conversion of salt solution to ammonia and HCl acid was monitored. The findings indicated that HCl and NH4OH concentrations were higher in PCCell membranes. The results showed that acid and base production from ammonium chloride can be realized simultaneously with both membranes and distillation waste can be disposed of.

NFLUENCE OF FLOTATION WASTE LEAD ORES AND SOLID WASTE FROM SODA PRODUCTION ON THE SWELLING OF AGLOPORITE

The article examines the influence of pore-forming waste from various industries on the porosity and swelling of the resulting lightweight agloporite material. Based on the results obtained, it was determined that an increase in the amount of soda production solid waste (SPSW) from 5 % to 15 % in the charge composition increases the swelling coefficient from 1.23 to 1.48, and proportionally reduces the volumetric weight of the resulting material from 1068 to 1020 kg/m3.

Online neutralization promotes water dissociation equilibrium forward in bipolar membranes to achieve 9.2 mol/L NaOH production

The bipolar membrane electrodialysis is a promising caustic soda production technique by taking advantage of the water dissociation under a reverse voltage bias. However, dissociation equilibrium is easily reached when forward water dissociation is equivalent to the back diffusion of acid and base into the salt chamber. Here, we propose manipulating the water dissociation equilibrium by introducing an online neutralization reaction for acid or base products. The results indicate that the online neutralization of the acid product could promote water dissociation forward in bipolar membranes, leading to an increase in the base yield of 27.7 % and a saving of 43.7 % in time in parallel with conventional operation. The boosting water dissociation via online acid neutralization results in the production of 9.2 mol/L NaOH, the highest recorded base concentration produced by bipolar membrane electrodialysis. The present study provides a simple and unique approach for manipulating the water dissociation equilibrium, suggesting the increasingly crucial role of bipolar membranes in base production.

Initial carbon capture pilot study in Solvay soda ash process

Aqueous ammonia is an alternative solvent for CO2 capture that has many advantages. In recent years, researchers have investigated ammonia as a promising solvent for CO2 capture from various gases. A significant emitter of carbon dioxide from the chemical sector is the soda ash industry. Since ammonia is an auxiliary substrate in soda production, it can easily be used to capture CO2 from tail gas streams. After CO2 absorption, process liquids can be returned to the production process, helping to reduce the use of raw materials.The main source of CO2 emissions to the atmosphere in the Solvay Process is the post-carbonation gas from the carbonating tower. It has been demonstrated that this process can be intensified and the use of calcium carbonate in the form of limestone is reduced by returning the carbon dioxide to the process. Stoichiometrically, one kg of avoided CO2 saves approximately 2.27 kg of limestone. This paper presents the initial results and lessons learned from the operation of the pilot plant for CO2 capture from tail gas streams of the Solvay Process. The process has been tested and implemented in a pilot plant with a gas flow rate of up to 4000 m3n/h. The influence of various process parameters has been investigated.

Intellectual control of the electrolysis process in the production of caustic soda

This article is based on the modeling of the operating mode of the membrane electrolyzer in the production of caustic soda through a neural network. In the course of work, a neural network model of the operation of the electrolyzer element was developed. Neural network software was used to create and train neural networks. The purpose of this work is to create an accurate model of the electrolyzer element using the following tasks was to create: the process of designing optimal structures of neural networks and their training, creating an electrolyzer model by training neural networks, as well as processing the modeling results. As a result of this work, a neural network model was developed, which allows to quickly and accurately calculate the result of the operation of the electrolyzer under any initial conditions.

ОЦЕНКА СВЕРХНОРМАТИВНЫХ ПОТЕРЬ ПОЛЕЗНОГО ИСКОПАЕМОГО НА ПРИМЕРЕ РАЗРАБОТКИ ИЗВЕСТНЯКОВОГО МЕСТОРОЖДЕНИЯ

The article presents methodological provisions for the assessment of increased mineral losses during open-pit mining of deposits with difficult mining and geological conditions. As an example, the indicators of mineral losses during the development of the Kostanok site of the Chanvin deposit of limestones used for the production of caustic soda are given. The actual level of losses exce-eding 30 % of the volume of extraction of raw materials has been established. The main reasons for the increased limestone losses compared to the level justified by the project are outlined. It was found that during the detailed exploration of the limestone massif, karst zones and areas with a high clay content, lying in the form of «veins» in areas of increased fracturing, were not identified. As a result, as a result of blasting, the exploding quarried, clogged areas with pure limestone are mixed, its contamination to values exceeding those allowed by the project, which leads to the loss of balance reserves of minerals during excavation. Recommendations are given for calculating the level of losses during the development of complex faces, which are characterized by the intermittency of rocks with productive limestone strata and karst zones.

Energy efficiency analysis of caustic soda production process

The increase in the cost of fuel and energy resources motivates industrial enterprises to introduce new technical solutions for their effective use. At the same time, as a result of the production ac-tivities of industrial enterprises, a significant amount of waste is generated that negatively affect human health and the environment. Such enterprises include caustic soda production plants, the technology of which is associated with the formation of thermal and combustible secondary energy resources in the form of steam, condensate, process water, etc. Such types of resources may be useful to use for the production of thermal energy for the company's own needs, or heating of raw materials or material flows involved in the technological chain. The technology of caustic soda production is considered it this paper, the basic structure of production is discussed, the material balance is given, options for improving the efficiency of energy resources are proposed.

Study of the characteristics of pavement elements made of reinforced soil with the use of secondary resources

The importance of using secondary resources on the basis of industrial waste is understood by both governments of developed countries and business (production of Portland cement using ground metallurgical slag as a mineral additive at Novotroitsk, Magnitogorsk, Sterlitamak, KatavIvanovsk and other plants in the South Urals). The use of secondary raw materials requires the creation of technological infrastructure for processing of secondary raw materials, the costs of which can be quickly recouped due to the cheapness and availability of industrial secondary raw materials and freeing the territory from environmental pollution. In order to recoup the costs of the infrastructure, it is necessary to guarantee full compliance of the quality of pavement elements with the requirements of GOST R 59120-2021. Secondary raw materials have a great variety and laboratory analysis of the quality of pavement elements is required in order to design compositions with the best quality, satisfying all regulatory requirements. In our work the authors present the results of laboratory research and evaluation of the possibility of using clinker-free lime-slag binder based on the mineral product of soda production and metallurgical slags to strengthen and stabilize soils for their use in pavement structures in the construction of roads for various purposes and climatic zones. It is experimentally shown that the addition of lime-slag binder in the amount of 8-10% of the dry weight of both cohesive (loamy soil, loamy sand) and non-cohesive (fine sand) soil allows to obtain reinforced soil with improved strength and elastic-deformative characteristics, which can be used instead of scarce natural crushed stone and gravel in the construction of underlying layers of pavements in the construction and reconstruction of highways. This technology can be used not only in the Russian Federation, but also in a number of other countries, including those with hot dry climates (e.g., the Republic of Egypt).

Ion injection bipolar membrane electrodialysis realizes over 8 mol/L NaOH conversion from a brine stream

AbstractThe chlor‐alkali process is currently the predominant technology for caustic soda production but has several major challenges, such as enormous energy demand and supply–demand imbalance between NaOH and Cl2 in downstream industries. Herein, we propose a novel ion‐injection bipolar membrane electrodialysis (IJBMED) system that is capable of boosting water splitting in a bipolar membrane with an ultrahigh current density while omittance concentration polarization in anion‐ and cation‐exchange membranes. The results indicate that the IJBMED approach enables one‐step conversion of the NaCl‐containing brine stream into 8.12 mol/L NaOH with specific energy consumption of 0.79 kWh/kg NaOH (23 wt.% → 25 wt.%), compared to 2.15 kWh/kg NaOH (28 wt.% → 30 wt.%) for the chlor‐alkali process. The advantages of low energy consumption and omittance of chlorine emissions suggest that IJBMED might be a promising alternative to the chlor‐alkali process, revealing a new route to reshape the chemical industry for caustic soda production.

MODIFICATION OF THE SLUDGE FROM SODA PRODUCTION

The problem of disposal of sludge from soda production is relevant in the Republic of Bashkortostan. Sludge from soda production are dumped into sludge collectors, which have a negative impact on the environment. There is a threat of contamination of groundwater with a highly mineralized still waste liquid. The increase of sludge in sludge reservoirs creates additional pressure and increases infiltration into groundwater. These processes are harmful for the ecological situation in the region.
 In this paper modification of soda sludge produced by organosilicon liquid, sodium liquid glass and stearic acid. Dependencies of change of oil capacity index on gasoline with respect to time were investigated. Analysis of results was carried out and optimal formulation of sorbent based on soda sludge for utilization of liquid phase of oil sludge was revealed.
 As a result of the studies of liquid glass as a hydrophobic compound it was found that small fractions of modified soda sludge repel water, creating a greasy sediment at the bottom, and granules, in turn, allow water to be absorbed and filtered without breaking their shape. To use modified soda sludge with liquid glass as a filter media in cassettes, granulation by extrusion is recommended. The resulting sorption materials based on the modification of soda sludge with sodium liquid glass can be recommended for use in facilities for the treatment of surface and waste water from heavy metal ions.

Bipolar membrane electrodialysis: A promising paradigm for caustic soda production

AbstractCurrently, a supply‐demand imbalance between NaOH and Cl2 in the chlor‐alkali process places a great burden on the environment. Bipolar membrane electrodialysis (BMED) is a competitive technology to produce acid and base due to its water splitting characteristics. To determine the competitiveness of NaOH production between BMED and the chlor‐alkali method, BMED was evaluated at various current densities with different NaCl concentrations. Results show that NaOH energy consumption in BMED is less than that of the chlor‐alkali method at a moderate salt concentration (<9 wt.%). Interestingly, the stack voltage suddenly increases during the later stage of BMED. It is speculated that the high osmotic pressure surrounding bipolar membranes restrains water transport into the interfacial layer. In addition, economic assessment indicates that BMED has less impact on global warming than the chlor‐alkali process. Overall, the BMED technique is a promising paradigm for base production in an economical and sustainable manner.

E-Chem Education: A Crash Course in Electrochemical Engineering for Caustic Soda Plant Design

The capstone chemical engineering senior process design course at Penn State in spring 2023 tasked students with designing a caustic soda process to partially meet the global demand for commoditized sodium hydroxide. This article disseminates our experience teaching senior chemical engineering students the core tenets of electrochemical engineering in a single class period for designing an electrolytic caustic soda process. In this E-Chem Education article, we relate key concepts found in chemical engineering (such as sizing up a reactor volume), which chemical engineering seniors are adept with, to electrochemical engineering principles (e.g., current density, voltage, and membrane electrode assembly area) for sizing up and costing out a chlor-alkali electrolyzer. Furthermore, we also discuss alternative electrolyzer designs outside the traditional chlor-alkali process, such as oxygen depolarized cathode (ODC) chlor-alkali and bipolar membrane electrodialysis (BPMED), for caustic soda production and the pros and cons of the alternative process designs.

Perspective in resource recovery from reverse osmosis brines: the case for sustainable seawater refineries for small islands

AbstractReverse osmosis has become the dominant technique for desalination while at the same time there is a steady increase in reliance on desalination systems for water production globally. Resource recovery and mitigation of adverse effects from brine discharge are important factors and are increasingly being considered by researchers and industrial actors. The island nation of Aruba, with over 100 years of commercial desalination history, is used as a case study to illustrate the possibilities of shifting from centralized seawater desalination plants to seawater refineries in which freshwater is considered only one of the possible products. We identify possible economic value from desalination plants of medium scale (as is the case in Aruba) from the production of magnesium, caustic soda, chlorine‐based products and rubidium and possible energy recovery possibilities through osmotic gradients and/or hydrogen storage while at the same time highlighting the insufficient potential for lithium harvesting from seawater desalination brines. We have found that the economic value from resources recovered from brine may be even larger than the value of the freshwater produced by these plants. Furthermore, reduction of salinity and quantity of brine can reduce the overall ecological impact from current brine effluents. © 2023 Society of Chemical Industry (SCI).

Structure formation and properties of a porous aggregate based on man-made waste

The article shows the possibility of obtaining a high-quality porous material with high physical and mechanical properties based on local clay raw materials and man-made waste. The influence of chemical industry waste ― phosphogypsum and alkaline waste of soda production ― on the mechanism of mineral formation and pore formation during the synthesis of lightweight material was studied. It has been established that the used waste accelerates the swelling process during firing, reducing the swelling temperature by 30‒50 o C, while obtaining a durable porous material. Ill. 3. Ref. 20. Tab. 3.

Efficiency of acid sulphate soils reclamation in coal mining areas

During the development of coal deposits, acid mine waters flowing to the surface cause the formation of acid sulphate soils. We study the effectiveness of soil reclamation by agrochemical and geochemical methods at the site of acid mine water discharge in the Kizel Coal Basin, carried out in 2005 using alkaline waste from soda production and activated sludge. A technosol with a stable phytocenosis was detected on the reclaimed site, and soddy-podzolic soil buried under the technogenic soil layer with no vegetation on the non-reclaimed site. The buried soddy-podzolic soil retains a strong acid рН concentration Н2О = 3. A high content of organic matter (8-1.5 %) is caused by carbonaceous particles; the presence of sulphide minerals reaches a depth of 40 cm. Technosol has a slightly acid pH reaction H2O = 5.5, the content of organic matter due to the use of activated sludge is 19-65 %, the presence of sulphide minerals reaches a depth of 20-40 cm. The total iron content in the upper layers of the technosol did not change (190-200 g/kg), the excess over the background reaches 15 times. There is no contamination with heavy metals and trace elements, single elevated concentrations of Li, Se, B and V are found.

Evaluation of an Ocean Reanalysis System in the Indian and Pacific Oceans

This paper describes an ocean reanalysis system in the Indian and Pacific oceans (IPORA) and evaluates its quality in detail. The assimilation schemes based on ensemble optimal interpolation are employed in the hybrid coordinate ocean model to conduct a long-time reanalysis experiment during the period of 1993–2020. Different metrics including comparisons with satellite sea surface temperature, altimetry data, observed currents, as well as other reanalyses such as ECCO and SODA are used to validate the performance of IPORA. Compared with the control experiment without assimilation, IPORA greatly reduces the errors of temperature, salinity, sea level anomaly, and current fields, and improves the interannual variability. In contrast to ECCO and SODA products, IPORA captures the strong signals of SLA variability and reproduces the linear trend of SLA very well. Meanwhile, IPORA also shows a good consistence with observed currents, as indicated by an improved correlation and a reduced error.