Biomass Cogeneration Energy Plants
Downer Energy Systems (DES) has the capability and experience to deliver "turnkey" Biomass to Energy Plants. In addition to such complete "design and construct" power generating and/or process steam plants, DES can also engineer system packages of plant tailored to complement larger systems supplied by others.
The purpose of the Plant is to provide reliable steam and power supplies to the neighbouring host (eg Sugar Mill), and power to the electricity distribution network. Excess biomass from the host plant process and/or other fuel such as woodwastes is used to fuel the boiler throughout the host industry's annual season.
The boiler supplies steam to an extraction, condensing steam turbine-generator unit which would have a nominal output typically in the range of 25 to 60MW.
The steam turbine has several extractions to supply steam for the host plant process and for low pressure boiler feedwater heating.
Exhaust steam from the turbine is condensed in a surface condenser which is cooled, in turn, by an induced draft mechanical type cooling tower. Condensate from the condenser is heated by a low or high pressure feedwater heater, being deaerated either via a deaerating condenser or feedwater storage tank, and is finally returned to the boiler.
Required steam flows, pressure and temperature conditions are determined by the process system requirements and demand. Given basic issues of economic viability of the host & cogeneration processes, it is extremely important that the Cogeneration Plant is designed to maintain high reliability of equipment and high availability of steam supply.
The following is a brief list of major equipment typically included:
- Biomass fired boiler
- Biomass reception including fuel handling system and storage facilities
- Flue gas cleaning system
- Ash and dust handling system
- Steam turbine generator Unit
- Surface condenser and condensate system
- Induced draft mechanical type cooling tower and circulating water system
- Low or high pressure feedwater heater
- Deaerator & feedwater storage tank and feedwater pumping system
- Water treatment plant including storage tanks
- Compressed air plant
- ICMS (Integrated Control and Monitoring System)
- Plant electrical system
- Transformers, switchgear etc
- Civil & other building works
Key objectives for biomass projects include:
- quality to meet objectives of stakeholders - performance, efficiency & operating cost
- low Capital cost and optimised performance
- environmental performance
- meet safe working conditions
- minimal disruption to host process operations
- operation on a wide range of fuels
- plant life
- high availability of steam and power production