Trona Ore Research Articles

Determination of Carbonate and Bicarbonate in Specific Samples of Trona Deposit

Trona is one of the natural forms of sodium carbonate minerals, it is well known as (sesquicarbonate) or (trona) and is known in Arabic as (natron) or (atrun). The possibility of determining some constituents of trona ore was studied, using the methods of purification, separation, titration gravimetric analysis and calcination. The aim of this study is to determine the major chemical Constitutes of three types of trona from different locations in Sudan, A chemical analysis has been carried out on these samples to determine their major constituents, and their quantities, using different analytical techniques. From the results obtained, it was found that the percentage of carbonate and bicarbonate for Northen, Westen, and Southern Darfour, were (35.52%: 18.19%), (25.87%: 12.20%) and (16.82%: 6.24%) respectively. These results suggest that the use of trona deposits for soda ash production is promising and important. We can recommend the use of trona as a source for the production of sodium carbonate.

Coarse Beneficiation of Trona Ore by Sensor-Based Sorting

Coarse Beneficiation of Trona Ore by Sensor-Based Sorting

Preparation and Characterisation of Activated Carbon from Palm Mixed Waste Treated with Trona Ore.

This study explores the use of a novel activating agent and demonstrates the production and characterisation of activated carbon (AC) from a combine palm waste (CPW) in 3:2:1 proportion by weight of empty fruit bunch, mesocarp fibre and palm kernel shell. The resulting biomass was processed by a microwave-assisted method using trona and compared with material produced by conventional routes. These results demonstrate the potential of trona ore as an activating agent and the effectiveness of using a combined palm waste for a single stream activation process. It also assesses the effectiveness of trona ore in the elimination of alcohol, acids and aldehydes; with a focus on increasing the hydrophilicity of the resultant AC. The optimum results for the conventional production technique at 800 °C yielded a material with SBET 920 m2/g, Vtotal 0.840 cm3/g, a mean pore diameter of 2.2 nm and an AC yield 40%. The optimum outcome of the microwave assisted technique for CPW was achieved at 600 W, SBET is 980 m2/g; Vtotal 0.865 cm3/g; a mean pore diameter 2.2 nm and an AC yield of 42%. Fourier transform infrared spectrometry analyses showed that palm waste can be combined to produce AC and that trona ore has the capacity to significantly enhance biomass activation.

A novel low-cost method of silica aerogel fabrication using fly ash and trona ore with ambient pressure drying technique

Highly porous and hydrophobic silica aerogel is fabricated using fly ash and trona ore as the starting materials and the cost-effective ambient pressure drying technique. The optimal calcination parameters are determined as temperature of 850°C, holding time of 2h, and the trona ore/fly ash mass ratio of 1.4. The CO2 release mechanism during calcination is proposed and has been verified by the Thermogravimetric and Differential Scanning Calorimetry analysis (TG/DSC) and X-ray fluorescence (XRF) technique. The hydrogel is derived from reacting the calcination mixture with sulphuric acid solution, followed by filtration. The impurities can be effectively removed through water washing and solvent exchange processes. No ion exchange resin is used in this preparation method, and thus it is a safe, inexpensive and much more straightforward process. In order to minimize drying shrinkage, the hydrogel is first transformed into an alcogel by soaking in ethanol, after which the alcogel is surface modified with the hexane/ethanol/trimethylchlorosilane (hexane/ethanol/TMCS) mixture solution. It has been observed that the specific surface area, BJH desorption pore volume, and BJH desorption average pore diameter all first increase and then decrease so that reach to the maximum values once the heat treatment temperature approaches 500°C due to the oxidation of CH3 groups on the silica skeleton surface. The final product presents special characteristics including: (1) high thermal stability for maintaining hydrophobicity up to 476°C, (2) contact angle of the as-dried silica aerogel as high as 151°, (3) silica particle size of ca. 3–6nm, agreeing well with the model as reported, (4) and the 500°C heat treated sample possessing a large specific surface area of 856.2m2/g, a large pore volume of 2.92cm3/g, and a BJH desorption average pore diameter of 17.1nm. The proposed inexpensive approach produces silica aerogel with superior properties and is a scalable-manufacturing method for large-scale industrial production.

Assessment of soda ash calcination treatment of Turkish trona ore

Trona is relatively rare, non-metallic mineral, Na2 CO3 · NaHCO3 · 2H2 O. The pure material contains 70.3% sodium carbonate and by calcination the excess CO2 and water can be driven off, yielding natural soda ash. The terms soda ash and sodium carbonate are used interchangeably. Trona calcining is a key process step in production of soda ash (sodium carbonate anhydrate) from the relatively cheap trona ore. The calcination reaction may proceeds in a sequence of steps. Depending on the conditions, it may result in formation of either sodium carbonate monohydrate (Na2 CO3 · H2 O), sodium sesquicarbonate or weigschederite (Na2 CO3 · 3NaHCO3 ). The Beypazari Turkish trona deposit is the second largest deposit in the world with the content of 84% trona. The decomposition of trona appeared to be a single stage process across the temperature range studied (150-200 °C) with the representative samples of different size fractions in the draught up metallurgical furnace. The optimum particle size and calcination time were −6.35 mm and 30 minutes, respectively, at calcination temperature of 175 °C in a metallurgical furnace. Microwave-induced dry calcination of trona was possible and 5 minutes of calcination time at a power level of 900 was sufficient for complete calcination of −6.35 mm feed. This includes short time calcinations with the goal of improving economics and simplifying the thermal process.

TREATMENT OF OILFIELD PRODUCED WATER: A CLEANER PROCESS FOR PRODUCING SODIUM CARBONATE (SODA ASH)

The objective of this research was to obtain soda ash from oilfield produced water. The association between produced water and the conditions to produce soda ash, its processes and reactions, inspired the development of this innovative research. With the goal of transforming this wastewater in a high value product, this research performed and compared different treatment processes. An anionic surfactant was used in the flotation process of the dispersed oil phase, and sodium carbonate was employed to promote calcium and magnesium precipitations. The relationship between the liquid effluents and solid wastes with the quality of the soda ash produced was established. The quality parameters for treated water were determined, and the different streams derived from these treatments were used in the production of soda ash. The soda ash obtained in this research presented physicochemical composition similar to the one of a carbonate mineral (trona ore). The yields were as high as 80%. This process allowed to treat and to transform produced water, an effluent that is harmful to the environment, into soda ash which is largely used in the industry.

Environmental isotopes and noble gases in the deep aquifer system of Kazan Trona Ore Field, Ankara, central Turkey and links to paleoclimate

Environmental isotopes and noble gases in groundwater samples from the Kazan Trona Ore Field are studied to establish the temperature change between the Holocene and the late Pleistocene. Noble gas temperatures (NGTs) presented in this study add an important facet to the global paleotemperature map in the region between Europe and North Africa. The groundwater system under investigation consists of three different aquifers named shallow, middle and deep in which δ18O and δ2H vary from −8.10‰ to −12.80‰ and from −60.89‰ to −92.60‰ VSMOW, respectively. The average isotopic depletion between unconfined and confined parts of the system is −2.5‰ in δ18O and −20‰ in δ2H. It is not possible to explain this depletion solely with the elevation effect. Recharge temperatures derived from dissolved atmospheric noble gases reflect the current average yearly ground temperatures (13°C) for samples collected near the recharge area but are 3 to 8°C lower than today's temperatures in the deep aquifer system. Low 14C activities and high He excesses in the confined parts of the aquifer system suggest that the water in the deep aquifer was recharged during the last Pleistocene under considerably cooler climatic conditions.

Environmental Isotopic Evaluation of the Springs Located in Kazan Trona Basin in Central Turkey

Abstract Kazan Trona ore field, the second discovered deposit in Central Turkey, is planned to be extracted by solution mining technology. Understanding the hydrogeology of the springs in such an area is vital since they can be affected during mining operations. The aim of this study is to provide an isotopic approach by utilizing environmental isotope techniques to the springs in the study area, thereby, to enhance the understanding of their occurrence by complementing the previous geochemical studies. Here, the isotopic signatures and the recharge elevations of the springs are demonstrated together with their field parameters. The relationship between δD and δ18O suggest strong evaporation in some of the samples after recharge. For those springs, the unmodified signatures were determined and the recharge elevations were calculated to be between 1100 and 1248 m. These elevations correspond to Incirlik and Asmalidere Members and upper Neogene units. The relationship between Tritium and Electrical Conductivity suggested that SP-6, SP-3 and SP-4 have shallow circulation when compared to SP-7 having both the lowest tritium and highest EC value. This finding is in accordance with the geochemical data, which suggests SP-7 emerges from the deeper, older groundwater present above the trona deposit.

Production of trona concentrates using high-intensity dry magnetic separation followed by flotation

Soda ash, an essential raw material for major industries, such as the glass, chemicals, soap and detergents, pulp and paper, mining and water treatment industries, is traditionally produced by chemical and thermal treatment of trona ore. The treatment processes for trona ore are not only chemically expensive but also energy intensive. Hence, the production of a high-purity trona concentrate at a lower energy and operating cost is of considerable interest to the trona industry. In this study, we describe a possible two-stage process for concentrating trona ore, involving dry magnetic separation followed by flotation, to remove insoluble impurities from the trona ore. The results showed that a trona concentrate of 91.7% purity with a recovery 91.1% can be obtained by two-stage magnetic separation, which could be further improved to 98.1% purity at a recovery of 83.8% by subsequent flotation of the non-magnetic trona product. The purity of trona concentrate is limited by the particle size and impurity content of the trona ore. The operating parameters for magnetic separation and flotation have been identified to obtain an acceptable quality concentrate.

Evaluation of flotation technology for the trona industry

Trona ore consists mainly of trona, sodium sesquicarbonate dihydrate (Na 2CO 3·NaHCO 3·2H 2O), including minor undesirable insoluble materials. With the present industrial practice, there is no particle separation process to remove these insoluble minerals prior to thermochemical processing. In this current research appropriate conditions for trona flotation technology were established from exploratory bench-scale experiments, and the conditions obtained from the bench-scale experiments were also applied to pilot scale flotation tests. In this regard various process variables such as amine dosage, flotation percent solids, amine to oil ratio, pH of amine solution, collector structure, brine composition, feed particle size, etc. were studied to establish the preferred conditions and operating variables for pilot-plant testing. Additional information regarding the mineralogy of the system and collector characteristics is also reported to provide further analysis and explanation.

Contact angle and bubble attachment studies in the flotation of trona and other soluble carbonate salts

Trona, Na 2CO 3 · NaHCO 3 · 2H 2O, is mined as the primary source for sodium carbonate production in the United States. Recent studies have shown that the flotation method can be used for pre-processing of trona ore to remove insoluble mineral contaminants for the production of soda ash (sodium carbonate). Studies with carbonate salts suggest that certain important factors can affect their flotation response, including viscosity of the brine and interfacial water structure. Flotation studies showed that contrary to the strong flotation of NaHCO 3 with both anionic and cationic collectors, Na 2CO 3 does not float at all. Based on the analysis of interfacial water structure in saturated brines, Na 2CO 3 was found to act as a strong water structure maker, whereas NaHCO 3 acts as a weak water structure maker. Bubble attachment time measurements suggest that collector adsorption at the surface of NaHCO 3 induces flotation; this is not the case for Na 2CO 3. Contact angle measurements indicated that the surface of Na 2CO 3 is hydrated to a great extent, whereas the NaHCO 3 salt surface is less hydrated. These results reveal that there is a strong relationship between the interfacial water structure and the contact angle of these salts. The less stable NaHCO 3 surface is ascribed to the interfacial water structure which allows for NaHCO 3 flotation with both anionic and cationic collectors.

Effects of solution mining on groundwater quality in the Kazan trona field, Ankara-Turkey: model predictions

Three aquifer systems as deep, middle, and shallow were identified in the Kazan trona ore deposit area. The flow conditions and the interaction between various layers were conceptualized into a site hydrogeological model. Each aquifer system was hydraulically and chemically characterized and represented in a numerical groundwater model. The resulting model has been calibrated under steady-state and transient conditions using available data. The flow model was used in conjunction with a three-dimensional solute transport model to assess the impacts of the pilot well solution mining of the trona deposit on groundwater resources during operation and post-operation periods. The results of operation period indicate that, even under the worse conditions (50 times increase in vertical hydraulic conductivity due to subsidence), ion contribution from the mine area with 118,000 mg/l maximum concentration would be about 58 mg/l into the deep aquifer system. This contribution is about 1.45% of the existing concentration (4,000 mg/l) in the deep aquifer. After 1,000 years of post-operation period, ion contribution from the mine area with maximum 119,000 mg/l concentration would be about 205 mg/l into the deep aquifer under extremely worse conditions. This contribution is about 5–20% of present concentrations in the deep aquifer. Retardation factors, which were not considered during model simulations would decrease the predicted concentrations. It is concluded that pilot well solution mining of the trona deposit would not have significant impact on the quality of groundwater resources in the overlying aquifers.

Determining the stress and convergence at Beypazari trona field by three-dimensional elastic–plastic finite element analysis: A case study

In this paper, deformation and failure characteristics of the main drift, T-2000, and a roadway, T-3000 excavated for Beypazari trona (natural soda) underground mine, which is located in Ankara, Turkey, were investigated by in situ measurements and numerical analysis. T-2000 was planed as a main drift with a length of 965 m, 14° inclined and excavated with an area of 18 m 2. The T-3000 roadway was driven in the trona ore body for the first stope. Load and convergence measurements were carried out at seven stations installed in main drift (T2000) and roadway (T3000). Measurement results indicate that the total convergences at all the stations were below 1% of the total gallery height and deformation rates were reduced significantly. Three-dimensional numerical modeling was performed to analyze the deformation and failure behavior of the drift for three different models using an elasto-plastic finite element method (FEM) approach considering Drucker–Prager failure criterion. The results of the numerical analyses were found to be comparable with in situ measurements.

Impact of the mechanical characteristics of weak rocks and trona ore beds on the main drift deformation at the beypazari mine, Turkey

Abstract In northern Turkey, the Main Drift, T-2000, and a roadway, T-3000, were excavated for Beypazari trona (natural soda) underground mine project between the years 1999 and 2001. This work was one of the most important mining projects in Turkey in the last decade. T-2000 was designed as a main drift with a length of 965 m, 14° inclined and excavated with a cross-sectional area of 18 m 2 . The T-3000 roadway was driven in the trona beds for the first production panel. In this study, in situ and laboratory studies have been made to define the formations through which the drift has been driven. In situ engineering geology measurements were carried out consisting of field observation, mapping, boreholes and laboratory tests on samples collected from the trona field and the boreholes. After drift excavation and support installation, the deformations and the loads on the supports were measured. As a result of this study, the deformational characteristics of the trona ore beds and weak rocks and their effect on the main drift (T-2000) deformation have been determined. The importance of this study lies in the fact that most natural soda mines in the world apply room and pillar mining methods. This study is probably the first investigation on underground openings with steel-set support systems and rock deformations in natural soda beds.

Wet calcining of trona (sodium sesquicarbonate) and bicarbonate in a mixed solvent

Trona ore is used in large amounts for the production of soda ash. A key step in this process is the conversion of trona (sodium sesquicarbonate: Na 2CO 3·NaHCO 3·2H 2O) into soda (sodium carbonate anhydrate: Na 2CO 3). Currently, this conversion is done industrially by calcining of the raw ore in rotary calciners at ca. 120°C or higher (Natural Soda Ash—Occurrences, Processing, and Use, Van Nostrand Reinhold, New York, 1991, p. 267). Trona can however be converted at lower temperatures by using a “wet calcining” technique. In this technique, trona is contacted with an organic or mixed organic-aqueous solvent at a conversion temperature that depends on the water activity of the used solvent. In pure ethylene glycol this temperature can be as low as 55°C. The conversion by “wet calcining” occurs very similar to that in the regular dry calcining process via a solid phase conversion. The anhydrate crystals form directly from the solid trona. This produces pseudomorphs (J. Chem. Eng. Data 8(3) (1963) 301), i.e. agglomerates of fine anhydrate crystals (1–10 μm). At high temperatures, dense, finely pored agglomerates are formed, while the outer shape of the agglomerate retains the prism shape of the trona crystal. At low conversion temperatures, loosely packed or even unstable agglomerates are found.

Production of sodium carbonate from soda ash via flash calcination in a drop tube furnace

This paper described the production of sodium carbonate via flash calcination of Turkish trona ore in a drop tube furnace. It has been observed that the loss of weight also increases with the increasing temperature of calcination. The production of sodium carbonate from the saturated solution of raw soda has been realized by a crystallization process in vacuum at 360 K. As a result, dense soda ash of 99.8% purity has been produced.

Control Schemes for an Industrial Rotary Calciner with a Heat Shield around the Combustion Zone

Soda ash (sodium carbonate) is produced by calcining natural trona ore (sodium sesquicarbonate) in rotary calciners. Shell overheating, the consequent deformation of the calciner shell, and heat loss are frequently encountered problems during this operation. Installation of a concentric, metallic heat shield around the calciner's combustion zone can help to reduce the shell temperature and recover some of the energy that would otherwise be lost. Another problem often encountered is the deterioration of product quality when the system inputs deviate from their design rates. A mathematical model of the calciner with a heat shield is used to design different control schemes in order to maintain the product quality. Performance of the designed control schemes is demonstrated via computer simulation.

Sodium Hydroxide Demand Is Booming And Supplies Are Dwindling

Compared with 1994, this year likely will be a tame one for the sodium hydroxide market. Spot prices for the widely used industrial chemical—in industry referred to as caustic soda—skyrocketed beyond $300 per ton from an extraordinary low of about $30 per ton last February. A huge upturn in demand last year, coupled with possible future constraints on production of caustic soda as environmental concerns place limits on its coproduct, chlorine, is forcing chloralkali producers to look for ways to break, or at least reduce, the tie between caustic soda and chlorine. One way is to produce caustic soda from trona ore. The wild ride for caustic soda started with large inventories and a recovery in demand for chlorine as the U.S. pulled out of recession. Caustic inventories were building, says Helmut Metzler, Occidental Chemical's business director for caustic soda. Formosa Plastics' 620,000-ton-per-year Point Comfort, Texas, plant was coming online, he says. Everyone was scared ...

Trona resources in southwest Wyoming

Bedded trona (Na2CO3·NaHCO3·2H2O) in the lacustrine Green River Formation of Eocene age in the Green River Basin, southwest Wyoming, constitutes the largest known resource of natural sodium carbonate in the world. In this study, 116 gigatons (Gt) of trona ore are estimated to be present in 22 beds, ranging from 1.2 to 11 meters (m) in thickness. Of this total, 69 Gt of trona ore are estimated to be in beds containing less than 2 percent halite and 47 Gt in beds containing 2 or more percent halite. These 22 beds underlie areas of about 130 to more than 2,000 km2 at depths ranging from about 200 m to more than 900 m below the surface. The total resource of trona ore in the basin for which drilling information is available is estimated to be about 135 Gt.

FMC introduces lower cost soda ash process

The board of directors of FMC, the largest U.S. producer of soda ash, has approved the first phase of a major project that the company says will significantly lower soda ash production costs at its Green River, Wyo., facility through use of a new proprietary manufacturing technology. A second phase of the project will increase production capacity at the facility. The key to the new system lies primarily in the mining of trona ore, which is processed to make soda ash, and in disposal of the tailings, or waste ore. Under the process, which is a modification of FMC's solution mining technique, spent ore is injected back into the trona mine and deposited in mined-out areas by the same water stream used to solution mine the virgin ore being brought up for processing. By redepositing inert tailings in the mine, above-ground tailings storage is not needed. Five patents cover key aspects of the new process: ...