Modern control of mineral wool production process

Abstract

In this paper, the control of the plant for mineral wool production consisting of a number of the technological units of different sizes and complexity is considered. The application of modern equipment based on PLC (Programmable Logic Controller) and SCADA (Supervisory Control And Data Acquisition) configuration provides optimal control of technological process. Described supervisory and control system is consisting of a number of units doing decentralized distributed control of technological entities where all possible situation are considered during work of machines and devices, which are installed in electric drive and are protected from technological and electrical accident. Transformer station and diesel engine, raw materials transport and dosage, processes in dome oven, centrifuges, polycondensation (PC) chamber, burners, compressor station, binder preparation and dosage, wool cutting, completed panel packing and their transport to storehouse are controlled. Process variables and parameters like as level, flow, velocity, temperature, pressure, etc. are controlled. Control system is doing identification of process states changes, diagnostic and prediction of errors and provides prediction of behavior of control objects when input flows of materials and generates optimal values of control variables due to decreasing downtime and technic - economical requires connected to wool quality to be achieved. Supervisory and control system either eliminates unwanted changes in the production line or restricts them within the allowable limits according to the technology. In this way, the optimization of energy and raw materials consumption and appropriate products quality is achieved, where requirements are satisfied in accordance with process safety and environmental standards. SCADA provides a visual representation of controlled and uncontrolled parts of the technological process, processing alarms and events, monitoring of the changes of relevant variables, data archiving, choice of either automatic or manual control. Supervison of the production process by intuitive screens on monitors, and display terminal is allowed to the operator. Certain objects of plant are represented by the appropriate symbols whose color is changed depending on status (working, inactive status, stand by, failure, etc.). Symbols are associated with characteristic parameters and the variables whose current values are monitored by graphics and/or tables. Special attention is paid to alarm conditions occurring in the case of failure or exceeding the set limits of certain values. Alarm signal is manifested by sound and signal light, with a corresponding text message on the screen, with the date and time of occurrence and the request to the operator to confirm the alarm in some way. Alarms and other important data are stored in the database, including information about the time of removing the causes of the alarm emergence. Beside data acqusition and processing data of process variables and installed equipment state, the system also provides data archiving and generating and printing of daily, weekly and monthly reports. Based on these reports, analysis and appropriate corrections are being done to increase productivity. Specific data of drive functionality, raw materials and amounts of final products are available to management at any moment via Internet. Information about status of embedded equipment, devices and protective elements provide planning periodical reviews and remont some lines or whole plant. Then replacement of certain parts significantly contributes to efficienty of current, preventive and investment maintenance. In this way, reliability and safety of production plant are increased. With complete automatization of production process that is complex and multidisciplinary, demages and energy consumption are considerably decreasing, workforce is optimized, good quality of final product is achieved and plant work with full capacity is provided. Some technical solutions (diesel engine and transformer station supervisory, compressor station supervisory, electric drive regulation, dedusting system control, HVAC (heating, ventilation, and air conditioning) system control, transport and dosage system control) applied at realization of supervisory and control system for mineral wool production process, can be also applied to regulation large number of industrial processes.