150kW Pulverised Fuel and Fluidised Bed Combustor System

Overview

Pulverized fuel (PF) firing is the standard method for over 90% of thermal power production worldwide. This is available both in subcritical and supercritical forms, and appears likely to be the standard thermal energy technology for the next several decades.  R&D is also being directed to further improving its efficiency and exploring co-firing biomass and other wastes using PF technology as well as liquid biofuels.

Applications

Current plans for thermal power using coal in the UK anticipate that approximately 20% of British thermal power will continue to come from coal-fired units. This unit will permit support of these power plants to ensure that they perform at the highest possible levels with minimal environmental impact.  The unit can also be used for ash deposition and fouling studies under controlled temperature conditions.

System Description

The Cranfield facility comes with an integrated combined heat and power (CHP) module as well as a dedicated flue gas recycle facility which permits operation in the oxy-fuel mode, and enables research into carbon capture technologies for fossil fuels, co-firing or indeed gasification options.  A remarkable feature of this unit is that it can also operate at significantly higher solids loadings and can function as a 150 kWth CFB unit as well as in the PF mode.

Integrated components

The system also has a dedicated EGR system including a humid air turbine (HAT), which will enable research into carbon capture technologies from natural gas. Cranfield’s facilities are also able to run for extended periods as Cranfield has extensive infrastructure, such as bulk storage of oxygen, and appropriate manifolding design to allow tests of durations of hundreds to thousands of hours where necessary to simulate a complete range of gas and temperature conditions. This unit is also equipped with an advanced gas mixing system, and complete safety detection system. Also, this unit includes fuel pre-treatment (shredding, milling and drying) and a pelletiser prior to the thermal energy conversion process.

Analytical Capability

This unit is equipped with temperature probes and sampling ports permitting optical sampling.  The unit also has an extensive range of gas sampling probes, and measurement facilities including Fourier Transform Infra-red spectroscopy (FTIR) and is capable of measuring emissions ranging from gas phase to fine particulates. Specifically this facility is equipped with a sensitive monitoring technique (electrochemical noise/probes) to evolve the SO3 chemistry, to evaluate the dew point importance and to control the operating temperature conditions for EGR options.