Technology

Our modular process permits partners to tailor the technology best-suited to their market needs. Our modules are designed around three types of feed, each forming a unique set of products.

Types of Feedstock

  • ● Pulverized Coal (PC) Ashes – These ashes result from plants that pulverize the coal and burn it with heated air to produce energy. PC ashes typically contain little or no sulfur. PC ashes can be used as feedstock in Module 2 without requiring sulfur separation.
  • ● Fluidized Bed Combustion (FBC) Ashes – These ashes results from plants that burn waste coal and inject limestone to capture sulfur that is released during the combustion of the coal.
  • ● Flue Gas Desulfurization (FGD) materials are produced by scrubbers that are used to capture sulfur from flue gas. FGD gypsum is one of the more common FGD materials.
 
All Modules in Flowchart form

For PC ashes, where ash and gypsum (FGD) are separate, the gypsum may be processed separately in Module 1 while the ash proceeds to Module 2. For FBC ashes, the combined ash and gypsum may be processed through Module 1 to remove and convert the gypsum and the remaining ash may proceed through Module 2 and Module 3.

Module 1

Module 1: Gypsum Separation and Up Conversion

Process: A rapid-gas exchange process that converts FGD gypsum into ammonium sulfate crystals and powdered calcium carbonate.
Current Stage: Process simulation models have been validated at bench-scale.
Pilot-Scale Goals:
● Validate design in continuous operation
● Produce product samples for market testing
● Improve product quality
● Process optimization and troubleshooting

Ammonium Sulfate crystals Calcium Carbonate Powder

The above pictures are products resulting from bench-testing by Hawk Mountain Labs in 2017.

Early conceptual model of Module 1

Early conceptual model of Module 1 with two processing options that may run concurrently.

Module 2

Module 2: Ash Leaching, Concentration, Cementation, Precipitation

Process: A leach process for separating silica and metals from coal combustion products.
Current Stage: Simulation models developed for chloride and caustic leaches. Bench-scale validation began in 2017 to validate the leach processes and the gypsum/ash separation process for mixed and FBC feedstocks. Validation tests are anticipated to be completed in Q3-2018.
Pilot-Scale Goals:
● Validate design in continuous operation
● Integrate Modules 1 and 2 and validate in continuous operation
● Produce product samples for market testing
● Improve product quality
● Process optimization and troubleshooting

Module 3

Module 3: Rare Earth Extraction

Process: Separates and forms technology metal compounds and rare earth oxides from metallurgical-grade mischmetal concentrate. Mischmetal concentrate is a mixture of metals primarily comprising rare earth elements. Quantities of target metals and the costs to extract them will vary with coal source and type as well as burn method.

Demand for rare earth metals has been increasing rapidly as technology advances, especially over the last decade. Rare earth elements are used in many different applications including electronics, batteries, specialty alloys, fertilizers, and magnets, amongst many others.

Development

The following chart depicts our anticipated development schedule.

Business Development Timeline
 

Sankey Diagram

The Sankey diagram, below, shows relative material mass flow for an example continuous flow processing system incorporating all three modules for processing average bituminous FBC ash. FBC ash contains large amounts of gypsum which needs to be separated from the ash prior to processing. The separated gypsum may be processed in Module 1 while the ash proceeds to Modules 2 and 3.

Sankey Diagram of Material Flow