Environmental Clean Technologies Limited is developing a unique, low-cost method to dewater brown coal and transform this abundant, but widely unusable, resource into a Black Coal Equivalent (BCE).
Based on research initially conducted by CRA and University of Melbourne in the early 1980’s, the technology – Coldry – is a patented process that changes the naturally porous form of brown coal to produce a dry, dense pellet, via a process call ‘brown coal densification’.
The Coldry process offers benefits, including:
- A process that has been tested and proven successful on a wide range of brown coal types;
- A more energy efficient process for removing water from brown coal than firing the coal in a boiler;
- Enhanced efficiency in the process of generating electricity through use of Coldry pellets;
- Evaporative water loss reductions, and optional recovery of high purity water streams as by-products;
When applied to lignite and some sub-bituminous coals, the mechanically simple Coldry process produces a feedstock in the form of densified pellets that are stable, easily stored, can be transported and are of similar energy value to many black coals, whilst significantly reducing CO2 emissions compared to its original brown coal form.
- Coldry pellets can be used in local black coal fired power plants and transported safely over distance to black coal fired power plants
- 10-30% Coldry:Lignite mix can be used in existing lignite-fired plants for emissions reduction of 5%-15%, without modification to the plant
- 100% Coldry possible in significantly upgraded lignite-fired power stations
- New state-of-the-art black coal power stations can replace old, inefficient lignite-fired power stations, reducing emission by up to 40%
The Challenges for Brown Coal
- Low net energy values restrict available avenues to create value from brown coal assets
- High moisture drives high CO2 intensity when used in traditional brown coal fired boiler designs
- Its Pyrophoric nature restricts usage predominantly to mine-mouth applications
Balancing these disadvantages are positive traits of Brown Coal:
- High levels of high value volatile material
- Typically low ash and sulphur levels
- High chemical reactivity, which is desirable in conversion processes
What will Drive Coldry Adoption?
- Re-valuation of brown coal reserves based on enhanced energy value of upgraded lignite
- Export to thermal coal market providing a new revenue stream for existing brown coal mines currently only supplying mine-mouth power stations
- Opportunity to diversify into new product streams – Coal-to-liquids (CTL), fertiliser (Urea) etc
- Value added industry and jobs, enabled by a cost effective drying solution
- The growing global demand for high quality energy sources, and the supply-demand imbalance means that escalation of energy pricing is our future reality.
- Projected growth in coal based power generation of 1300 Gigawatts by 2030, mostly in Asia
- Uneven supply and demand driving development of previously uneconomic lignite resources
- Current focus on climate change has resulted in significant implications for brown coal fired power generators due to the high level of CO2 emissions
- Provides a least cost abatement solution for markets with a carbon price
- Coldry reduces emissions by up to 15% for existing brown coal fired power stations and up to 40% when used in modern black coal power stations