Design And Practice Of PLC Configuration Control System For Boiler Sootblowing

Fuel combustion in the furnace is a kind of extremely complex physical and chemical process. Non-combustible minerals in the fuel in the furnace become ash after combustion.Some of them precipite in the bottom slag trough, while most of the fine particles flowing with the flue gas flow, can deposit on the radiation heating surface, or at the back of the chamber of a stove or furnace convection heating surface, and gradually thickening,becoming loose dust layer or a solid residue, and affect heating surface heat transfer. Soot being not blown off in time, dust and slag deposition will be seriously increasing, taking great effects on the boiler running efficiency. By now, there is no effective way to prevent bond formation, sootblowing is therefore the most important auxiliary system for boiler running efficiently and stably. Reasonable advanced sootblowing control system, can improve the work environment and intensity of boiler operation labor, improve the efficiency and stability of boiler, and is of great significance in increasing the production efficiency and economic benefit of boiler enterprises.Facing dust and slag accumulation problems, boiler sootblowing process, equipments and system are studied in this thesis. Based on the detail study on PLC operation principle,system selection and configuration, man-machine interface(MMI) configuration control,et al, boiler sootblowing automation control system is designed according to the boiler sootblowing demands of the practical project. The automation platform, which is made up of Quantum 140 series PLC and industrial control computer with Kingview configuration software, effectively control the large quantities of the hearth, the long/half extending/retracting, and air preheating sootblowers.Application practice and the formal running operation of the practical project show that: The application of PLC greatly reduces the size volume, the hardware connection numbers and fault rate. The visually easy operation of the MMI configuration greatly improves the boiler operation environment and intensity. The advanced PLC configuration control system can also reliably control the flue gas temperature, improve the boiler running efficiency, increases the equipments’ service life, reduces the examining and repairing cost, and so that gains great comprehensive benefits.