European Bio-Energy Projects

INTCON
Objectives
The objective is to develop and
demonstrate an optimising general control
system to be used in biofuel fired boilers
for the production and co-production of
industrial power and steam or district
heating. The focus in this project will be on
a system suitable for a grate-fired boiler,
but necessary alterations of the control
strategies for other boiler types will also be
evaluated and defined. The system will be
easy to adapt to existing control systems.
It will minimise the emissions and
operational problems such as
slagging/fouling, and optimise the burn out
of ashes and the heat output. A control
system like this will be a useful instrument
to improve both the economy of using
biofuel for power and heat production and
by reducing the environmental impact. It
will, therefore, support the political target
of increasing the proportion of renewable
fuels in the energy system.
INTCON – A process control
system for biomass
fired plants
Problems addressed
Biofuels, both from forest/farmland and from
recycling, are in general very inhomogeneous with
large, timely variations in moisture content, size
distribution, ash content and ash properties.
Changes in fuel properties have to be met in a
correct way in order to maintain a good
economical process.
There is a general trend to increase the emission
constrains from combustion plants. Those firing
recycled biofuels, like demolitions, would have
to comply with the waste combustion directive.
All these demands call for the development of
a qualified system for controlling the operation
of a plant. The system is very complex and
includes a multileveled structure including
combustion and emission control, minimising
mainte-nance and handling overall power and
heat demands.
Project structure
A general control system suitable for all types of
boilers is complex and extensive. As a first step,
the objective of the present project is to develop
a control system for a grate-fired boiler where the
use of inhomogeneous fuel is common, where
the aerodynamic problems are the greatest and
where the methods for control is the least
developed. Alterations for pulverised fuel (PF) and
fluidised bed (FB) boilers will be evaluated and
the final results will include defined control
strategies for these types.
To accomplish the development of a novel control
system, a consortium has been formed by TPS,
CINAR, CIRCE and Technatom. TPS coordinates
the whole project and has an extensive
experience in biofuel and waste combustion in
108
most applications. CINAR is widely experienced
in the field of numerical simulation and, with
applications both in the field of CFD and Neural
Network (NN), will support the other partners.
CIRCE will have a special focus on slagging and
fouling but has also an in-depth knowledge of
combustion with PF and in FB. Technatom has a
vast experience in the processes and their control.
To make INTCON flexible it has a modular
structure where certain modules are highly
specialised for a particular application, whereas
others are of a general nature. The overall
structure for the chosen application is presented
in the figure below.
The Management Module (MM), where a linguistic
fuzzy tool is combined with a knowledge base
containing information on the boiler system, will
advise on the specific control modules for an
optimised and cost effective operation. The
learning capability will make the module available
for future adaptation to new situations.
A Real-Time Data Base (RTDB) is used for the
storage of data, both from the process and from
that calculated in the control system. There are
several routines for data treatment in the RTDB,
and the RTDB and MM modules are general to
all INTCON systems.
There is an Overall Boiler Control Module (OBCM),
essentially a shell for control modules for the
different tasks that have to be performed in
the boiler. In this project two general control
modules have been developed; a combustion
controller (CCM) and a slagging and fouling
controller (SFM). There is also a predictive
emissions monitoring module (PEMM).