ABSTRACT
Water supply is an important industry for the people's livelihood. Not only to meet
the needs of the pipeline network pressure and to ensure adequate water supply, but also
called for the improvement of water quality. As to conventional water treatment plant,
filter is the last structures of water purification processes, filter run a direct impact on
water quality. The process of filter backwash is complexity, if still used in manually,
labor-intensive, low productivity, so it is difficult to ensure the safety of this system and it
must be transformed to automatic systems.
In this paper, as a view of the
automatic control system for the water plant filter
requirements and process characteristics, the automatic control system for the
water plant
design
of a set of hardware and software based on the ControlLogix
system has been accomplished. When in the normal filtrate period,
in order to keep the constant level, designed the PID filter level control system
which is based on the water flow parameters. When receives backwashing
signals, the control system on how to enhance coordination between master PLC
and on-site PLC, has been compared and optimized.
According to requirements of the designed control system, the selection of
hardware devices, hardware configuration, I/O module wiring diagram,
procedures for the realization of control algorithm have been accomplished.
Keywords: water plant filter, constant water level on PID control, automatic
backwashing, coordinated control