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 the University of Melbourne in the early 1980s, 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 called ‘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 the 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 higher-value conversion processes

What will Drive Coldry Adoption?

Economic Security

  • Re-valuation of brown coal reserves based on the 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

Energy Security

  • 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

Climate Security

  • 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

Features & Benefits

The Coldry Process offers some unique features, with the end product, in turn, having some unique attributes. In summary, these are:

The Process

  • Uses low-grade waste heat, lowering energy costs and reducing the CO2 footprint
  • Is simple & mechanical, providing high reliability and easier maintenance
  • Is low temperature and low pressure, reducing energy consumption and extending equipment life
  • Is modular, immediately deployable, and consists of prefabricated components for easier construction in remote installations
  • Provides enhanced power station efficiencies through reduced evaporation losses
  • Provides ‘Class A’ quality water as a by-product

The Product

  • Exponentially enhanced net energy content increased up to 285% for 60% moisture Victorian La Trobe Valley Lignite
  • The self-ignition tendencies of typical Lignite is greatly reduced to that of normal Black Coals
  • Accumulation of up to 90% less Ash than typical black coal, increasing operational efficiencies and reducing removal costs
  • Immediately deployable in existing brown coal boilers (10% to 20% of total energy mix), decreasing coal requirements (7% to 14%), reducing emissions (6% to 11%) and reducing ash accumulation (2% to 4%)


ECT’s Coldry technology is a scalable, cost-effective lignite drying solution that produces a storable, transportable, energy-rich solid fuel pellet ideal for the lucrative thermal coal market, as well as providing an ideal feedstock for higher coal conversion applications such as coal to liquids, gas and fertiliser.

Additional Benefits

CO2 Emission Reduction

Existing brown coal power stations that consume Coldry pellets immediately gain benefits without the need for significant modifications to plant infrastructure including:

  • Emissions savings – 5% to 15% CO2 reduction
  • Reduced ash costs
  • Decreased cooling water consumption

These factors also drive the business case for inefficient brown coal-fired power stations to install high-efficiency, low-emission (HELE) coal-fired technologies with their ensuing efficiency and financial benefits, while achieving CO2 reductions of more than 30%.

High Gains

  • The Coldry Process represents high gains in coal drying and is extremely well suited to taking high moisture feedstocks of around 45-65% moisture to a product of around 12%
  • Our patented method of dewatering has now been proven and independently validated on coals from many global sites, including China, India, Indonesia, Germany, Poland, Greece and Australia


  • Coldry is a relatively simple and efficient mechanical process that alters the physical properties of the feedstock
  • It is not a process that requires costly chemicals to dry coal or has any associated water clean up costs

Low Temperature

  • Our process requires waste heat of around 40°C
  • This low heat is sourced via heat exchange from a co-located power station or other suitable industrial processes

Low Pressure

Coldry extrudes product under low pressure. Low pressure requires less energy.

Water Recovery

  • Coldry liberates large volumes of water, enabling optional water recovery
  • The water recovered from the coal is ready for immediate industrial use without expensive treatment and becomes potable with minor filtering

Sensitive to the Environment

Coldry is sensitive to the environment as combustion of this energy-rich, low moisture fuel enhances efficiency, and reduces CO2 emissions and other environmental damage.


Our Coldry plant is flexible and well suited for domestic markets (rapid-dry product) and export markets (high-quality product).

  • The Coldry plant is modular and, hence scalable
  • All sections of the plant are pre-fabricated off-site, then transported in shipping containers and assembled
  • Ideal for deployment at remote mine-mouth locations, where transporting oversized equipment is a challenge


Our plant creates a solid fuel that is cost-effective and greatly increases the value of the lignite feedstock in the face of rising black coal demand and pricing.

Power Station Integration Synergies

  • Our design integrates with power stations and delivers synergies
  • Coldry integration with the host power station acts as a heat-sink, reducing the need to take water from local rivers and other sources

Coldry is a patented process that changes the naturally porous form of brown coal to produce a dry, dense pellet, via a process known as ‘brown coal densification’.

The following process is applied:

Commercial Scale Design

The Coldry Pilot Plant has informed the design of the commercial-scale Coldry modules that will underpin commercial plants.

These modules have been designed to produce:

  • 340,000 TPA of Coldry from 60% moisture coals,
  • 440,000 TPA of Coldry from 50% moisture coals, or
  • 600,000 TPA of Coldry from 40% moisture coals.

ECT’s Coldry technology is expected to be a scalable, cost-effective low-rank coal drying solution that produces a storable, transportable, energy-rich fuel pellet ideal for the lucrative thermal coal market, as well as providing an ideal feedstock for higher value coal conversion applications.

The Coldry Product

Coldry BCE

Coldry is a solid fuel with a net energy value similar in range to that of many black coals.

Key Features

  • Exponentially enhanced net energy content increased up to 285% for 60% moisture Victorian Latrobe Valley Lignite
  • The spontaneous combustion risk of typical lignite is greatly reduced to that of normal black coals
  • Deployable in existing brown coal boilers (10% to 20% of total energy mix), decreasing coal requirements (7% to 14%), reducing CO2 emissions (6% to 11%) and reducing ash accumulation (2% to 4%)
  • Provides business case drivers for the introduction of modernised ultra-supercritical (USC) boilers, decreasing coal requirement (up to 48%) and reducing CO2 emissions (up to 40%) compared to existing brown coal power stations
  • Ideal feedstock for downstream processes such as gasification, coal to liquids and other coal-derived chemicals


Testing by the University of Queensland places Coldry in the same ‘spontaneous combustion’ risk range as thermal (black) coals currently exported from Queensland and NSW. The Coldry process changes the physical structure to the point it no longer has the same ‘high-risk’ of spontaneously combusting as raw brown coal.


As a black coal equivalent, the product is valuable and will enjoy the higher prices paid for black coal under certain market conditions. Also, the product attracts lower transportation costs in terms of energy per unit of mass, due to the removal of unwanted water.


The product is versatile and can serve as a valuable feedstock for power generation including subcritical, supercritical and ultra-supercritical black coal boilers, and gasification based chemical and fertiliser production processes.

Coldry pellets can be used in local black coal power plants co-located on brown coal mines or transported over distance to black coal power plants.

Product Test Results

The following indicative results show the analysis before and after processing.

Intellectual Property Strategy

Our core asset is our Intellectual Property and as such must inform and leverage our Business Strategy.

Key aspects of IP protection include:

  • Patents – The Coldry Process is covered by patents in all major markets with significant lignite deposits and a mature legal framework
  • Confidentiality Agreements – Engagement with potential partners and customers is covered by comprehensive agreements
  • Licence Agreements – Technology Transfer is protected by detailed agreements to minimise risk and maximise compliance

Patents – Coldry

CountryPatent No / Patent Application NoStatus
China (incl. Hong Kong)ZL200480031850.2Granted
IndiaPCT/AU2004/001319 or 1576/DELNP/2006Granted
New Zealand546098Granted

Note: The Company had originally applied for coverage in Brazil, but has elected to abandon that coverage due to the incompatible quality of the lignite (extremely high inorganic contamination levels).