When it comes to waste water treatment, the challenge for the operator and for the local authorities is a particularly significant one, since they key contributors to environmental protection and are required to comply with regulatory provisions.
Domestic and industrial wastewater routed by the collectors is treated at the factories or treatment plants. Regardless of their size, the goal remains the same: the elimination of micropollutants by biological or physico-chemical treatment in order to discharge quality water into the natural environment.
To carry out this task successfully, telemetry and SCADA is a valuable aid for contract operators, enabling them, among other things, to:
The treatments implemented vary according to the size of the station, the surrounding environment, the nature of the effluents, the surface area of the site, the discharge constraints, etc.
A SOFREL S500 or AS50 remote terminal unit is sufficient for performing the purification process in small treatment plants. Typically, in an extended aeration activated sludge purification plant with around fifteen engines, the telemetry device, thanks to its process control suite, will be capable of managing the following elements: lift station, travelling screen, sand/oil separator, ventilation, clarification, recirculation, sludge extraction and sewage units.
Beyond a population equivalent of 3,000, wastewater plants become more substantial and integrate additional treatments (deodorisation, dephosphatation, sludge treatment, stormwater basin, etc.). The purification process in these large treatment plants is often entrusted to Programmable Logic Controllers. The remote terminal units communicate with these PLCs and monitor correct functioning of the facilities, save all data required for operational purposes, generate operating reports, enable on-site or remote display of information, and supply self-monitoring data to the operator.
They also issue alerts in the event of malfunction, control and manage access to facilities, detect intrusions, and monitor levels of treatment products.
A strongly growing trend in small rural localities in particular, lagooning involves relatively extensive basins receiving waste water. This water is treated in a biological and natural way. These sites rarely have an electrical power supply. For measuring input and output flows, the installation of a SOFREL LT or LT-US data logger combined with a Venturi flume is an excellent solution for discharged water tracking and self-monitoring requirements.
The data logger can be connected to a rain gauge to record local rainfall levels, in parallel to the flowrate. Lastly, for these applications, the data logger can also control an autonomous sampler.