Overview

The Fluidised-Bed Reactor system (FBR) utilises low grade coal or other solid waste (such as Biomass, Agricultural Green/Wood Waste, MSW and Effluent Sludge) to produce environmentally clean hot gas for generating process steam and/or power steam, or for product drying applications. The FBR process includes low-temperature gasification followed by high-temperature combustion in one reactor, which has been commercially verified by independent experts as meeting the world's best practice for power generation. It has also been tested and proven as being suitable for a low-emission coal liquefaction.

The key innovations in the FBR system, initiated and invented by James Kwok, have been widely adopted and commercialized in the designs of Fluidised-Bed Combustion systems around the world. More than a decade after their initial implementation in the proprietary Fludised-Bed Reactor, the technology continues to be considered cutting-edge.

Typical arrangement of a Fluidised-Bed Reactor

A fluidised bed is a bed of hot inert particles suspended in thin air. The bed is maintained at a temperature between 750 and 950 degrees Celsius, at which temperature fuels will ignite rapidly and burn. The fluidising air is the air in which the particles are suspended and is also the combustion air for fuel. Combustion occurs in two stages: in the bed and above in the freeboard of the furnace.

In 1998 James Kwok initiated and co-developed with Prof Dr Udo Hellwig of ERK Germany the unique integrated 'shell-tubes', rated at 35t/h superheated steam generator at T400degC and P40barg, to power a 7MWt steam-turbine which was incorporated in the 25m high proprietary and patented Energy Equipment Fluidised-Bed Reactor (FBR).

Installations

There are currently many FBR units around Australia that have been built and are in commercial operation, with two also having been built in PRChina. A large-scale (5MWe) renewable power generating plant using 70,000 t/yr of garden waste (biomass) as fuel, was built using the latest Energy Equipment FBR technology and commissioned at Stapylton, Queensland. This plant was amongst Australia’s first using a multi-stage air condenser system for cooling (instead of water). The plant was constructed as an embedded generator for an Industrial complex in South East Queensland, Australia.

In 2002 this plant was granted with Australia’s first renewable energy generation and transmission license and renewable energy certification from the Australian Greenhouse Office (AGO) in Canberra. In 2003 this plant was successfully commissioned with independent expert verification from Burns Roe Worley (Melbourne, Australia). Other verifications were also conducted by Sinclair Knight Mertz (SKM, Sydney Australia); GHD Black & Veatch (Sydney, Australia and USA); and the Queensland State and Environmental Protection Authority; to confirm meeting designed performance, operational and emissions abatements.

FBR installed on green waste to energy site in Stapylton, Queensland

FBR of 25m in height installed in Stapylton, Queensland

James Kwok on site in Stapylton, Queensland

James Kwok on site in Stapylton, Queensland

Standard 10-30MW thermal FBR Steam Generator, pressure up to 40 barg

Coal Gasification under construction in PRChina

FBR Effluent Sludge to Energy installation - processing 100t per day

Also in 2002 James Kwok and Dr Rajinder Malik (previously with The University of Sydney, Chemical Engineering Faculty) developed, designed and documented the process for ethanol production using 85kT/yr of cellulose as feed stock from agriculture waste, in a proposed project in Trangie District, Dubbo City, Central New South Wales of Australia. This project was planned to feature a 10MW capacity FBR as a co-generation system for the 30ML/yr ethanol plant. With a dedicated bio-farm to be located adjacent to the plant, the proposed project was granted with Australia’s first EPA approvals. The Australian Federal Government’s anticipated ethanol legislation was not passed at that time and the project was shelved. However in the latter part of 2010, mandatory 10% ethanol-mix legislation has since been passed and E10 fuel has now been introduced to replace the fuel previously known as unleaded. Click the schematic below for a larger image.