Automation of the technological processes of wastewater treatment: case study of the Minsk wastewater treatment plant of UE Minskvodokanal

Summary

The experience of UE Minskvodokanal in developing and establishing of automated control systems for the technological process of wastewater treatment is presented using the example of several structures of the Minsk wastewater treatment plant. The goals and tasks performed by the automated process control systems at the plant are described. The structure and operating modes of the implemented systems are presented. The stages of the wastewater treatment process are considered in detail: screening, sand removing and processing, supplying and distributing air across sections of the aeration tanks. As part of the automation of the presented treatment stages, the general design of the automated process control system is described, the operating features, the objects used and automation modes are given. Special attention is paid to the need for simple and reliable control algorithms. The ultimate goal of upgrading the automated process control system of the Minsk wastewater treatment plant is the maximum degree of automation and supervisory control covering the entire technological chain of wastewater and sludge treatment based on the simple and reliable principles.

Key words

wastewater , screens , sand catchers , algorithm of control , SCADA-system , aeration tanks , automation of technological processes , work station

Current trends in water supply optimization
(review)

Summary

The main aspects of introducing SCADA-systems for automated control of water supply and wastewater disposal processes: synchronization of software with the installed control systems; erection of a programmable logic controller, introduction of algorithms of systemic optimization, synchronization of the telemetry system and control system at the facilities are considered. The basic technical factors (e. g. when a programmable logic controller and RTU blocks have been already connected to the centralized control system; the availability of separate algorithms at RTU-block level) that shall be taken into account when making a decision on the introduction and in the process of designing automated control systems as well as the principles of SCADA system operation by a special operating department are described. By the example of the companies that have introduced SCADA-systems for water and wastewater industry an analysis of the results in terms of absolute and relative indices is given. The capacity of some pumping stations operated by EBMUD Company was improved by more than 27%. During the first week of the system operation WSSC Company registered about 400 dollars per day cost cutting just at one of the pumping stations. For the second week this amount increased to 570 dollars per day and for the third week exceeded 1000 dollars per day. Similar effect was noted at other 17 pumping stations. Thus, SCADA-systems contribute to financial advantages by optimized and improved efficient control of water supply and wastewater disposal processes. The use of the relative international experience for the project implementation in Russia has been an effective solution.

Key words

automated control system , water and wastewater management , SCADA-system , plant management , automated accounting