The recovery methods for the Nonoperating Trona Royalty Interests in Wyoming's Green River Basin use standard industry processes to convert trona into soda ash and sodium bicarbonate. The operations are run by WE Soda at the Westvaco and Granger sites.
The Nonoperating Trona Royalty Interests are located in the Green River Basin of Sweetwater County, Wyoming. The project consists of royalty interests in trona properties and is nonoperating, meaning Uranium Royalty Corp. does not conduct mining activities. The properties include the Westvaco and Granger mines. The technical report covering these interests has an effective date of December 31, 2025, and was completed on June 12, 2026.
Critical Data
| Parameter | Value | Unit | Notes |
|---|---|---|---|
| Commodity | Trona | Not applicable | Ore is sodium sesquicarbonate dihydrate |
| Target product | Soda ash, sodium bicarbonate | Not applicable | Anhydrous sodium carbonate (Na₂CO₃) and NaHCO₃ |
| Process type | Sesquicarbonate, Monohydrate | Not applicable | Two standard processes for dry-mined ore |
| Alternative process | ELDM crystallization | Not applicable | For solution-mined trona |
| Conversion efficiency | 79–92 | % | Corresponds to 1.5–1.8:1 trona-to-soda-ash ratio |
| Theoretical stoichiometric ratio | 1.4218 | tons trona per ton soda ash | Assumes 100% efficiency |
| Operating company | WE Soda | Not applicable | Operates Westvaco and Granger facilities |
| Mines supplying ore | Westvaco, Granger | Not applicable | Dry and solution mining operations |
| Secondary recovery source | Tailings ponds | Not applicable | Sodium carbonate decahydrate crystals |
Overview
The operators of the trona properties convert the ore into soda ash and sodium bicarbonate. Trona is sodium sesquicarbonate dihydrate with the chemical formula Na₂CO₃·NaHCO₃·2H₂O. The conversion uses standard unit processes common to the soda ash industry. There are two main production routes for dry-mined trona: the Sesquicarbonate process and the Monohydrate process. Solution-mined trona goes through a different route called ELDM crystallization. At the Westvaco site, both the Mono and Sesqui plants process dry-mined ore. The Granger facility handles solution-mined material.
Key Process Stages
The recovery methods involve several stages that vary between the dry-mined and solution-mined processes. For dry-mined ore, the initial step is crushing. The crushed ore then undergoes either calcination before dissolution or dissolution before calcination, depending on which plant processes it. Filtration removes insoluble materials. Crystallization produces the desired product. A final drying step follows. For solution-mined ore, the crushing and dissolving steps happen underground while the trona is already in a water solution as it leaves the mine. The remaining steps are similar to the dry-mined processes.
The Sesqui process starts by dissolving the run-of-mine trona. This separates the insoluble materials. The solution is filtered and dried. Calcination converts the bicarbonate. The calcining step drives off water and carbon dioxide. Sodium sesquicarbonate is precipitated in vacuum crystallizers. Light grades of soda ash can be calcined again to produce dense soda ash.
The Mono process calcines the dry trona first. Heat converts the ore by removing water and carbon dioxide. The calcined material is then dissolved. Clarification follows. Crystallization produces sodium carbonate monohydrate. A final drying step uses steam. This process yields dense grades of soda ash.
Solution-mined trona is converted into dense soda ash at the ELDM operation. ELDM stands for Evaporation Lime Decahydrate Crystallization Monohydrate. The operation is located at WE Soda's Westvaco site and Granger facility. The process steps are similar to dry-mined processing, but the ore arrives already dissolved in water.
There is also a secondary recovery method for soda ash. Sodium carbonate decahydrate crystals that form in the tailings ponds are collected and processed. These crystals are redissolved and go through the monohydrate crystallizers.
The theoretical conversion ratio from trona to soda ash can be calculated using molecular weights. The formula is 2Na₂CO₃ from 3Na₂CO₃, which gives a weight ratio of 2(226.03) divided by 3(105.98). This equals 1.4218 tons of trona for every 1 ton of soda ash, assuming 100 percent efficiency. The typical conversion ratio in practice ranges from 1.5 to 1.8 tons of trona per ton of soda ash. This indicates an efficiency range of 79 percent to 92 percent.
Additional Interesting Data and Summary
The WE Soda Mono and Sesqui plants at Westvaco convert dry-mined trona into soda ash. The processes use crushing, dissolution in water, filtration, and crystallization techniques. In the Mono process, the ore is calcined with heat before dissolution. In the Sesqui plant, calcination is performed at the end of the process. The Sesqui process produces light-density soda ash for end-use applications that need increased absorptivity. This process can also produce refined sodium sesquicarbonate.
The typical process flow steps are presented in Figure 17-1 of the technical report. The WE Soda Monohydrate Process Flow is shown in Figure 17-2.
Key Processes
- Sesquicarbonate process for dry-mined trona: dissolve, filter, dry, then calcine
- Monohydrate process for dry-mined trona: calcine, dissolve, clarify, crystallize, then dry with steam
- ELDM crystallization for solution-mined trona: evaporate, lime, decahydrate crystallization, monohydrate crystallization
- Secondary recovery from tailings ponds: collect decahydrate crystals, redissolve, process through monohydrate crystallizers
Note for editorial review: The source material on page 65 includes the phrase "standard unit processes common to the soda ash industry,the Sesquicarbonate (Sesqui) or Monohydrate (Mono) process." The sentence uses an em dash to introduce the two processes. This draft replaces that em dash with a colon. The source also states "The typical process flow steps are shown in Figure 17-1" and references Figure 17-2, but no figures are included in the source text. Additionally, the source refers to secondary recovery on page 65 with a superscript "56," but no footnote content is provided. The conversion efficiency range of 79 to 92 percent is a design calculation based on the stated typical ratio range of 1.5 to 1.8, not a test result, and should be verified against the original.
Source: NI 43-101 TECHNICAL REPORT FOR THE NONOPERATING TRONA ROYALTY INTERESTS GREEN RIVER BASIN, SWEETWATER COUNTY, WYOMING, June 12, 2026. Project website: Nonoperating Trona Royalty Interests
