Design Of Thermal Power Plant Circulating Water On-Line Monitor And Water-Saving Management

Industrial water is largely used in the thermal power plant.In the operation of thermal power plant,circulating cooling water system accounted for 70%~80% in the whole water consumption of the thermal power plant.For the purpose of increasing the recycle rate of circulating cooling water in the thermal power plant,the designed system of circulating water on-line monitor and water-saving management in this paper can keep circulating cooling water from depositing and prevent pipelines from eroding in order to heighten the concentration ratio of circulating cooling-water system and obtain the water-saving target.First of all,the scaling mechanism of circulating cooling water is analyzed in this paper.Through the analysis,core parameters affected circulating cooling water of fouling are obtained.They are alkalinity and concentrate rate.However,alkalinity and concentrate rate can't be measured online directly based on the level of present technology.For the reason,this paper takes use of the soft measurement technology,demonstrates p H value characterization of the feasibility of alkalinity,concentration rate characterization of the feasibility of water-saving management,conductivity characterization of the feasibility of the concentrate rate.Then,in order to realize the on-line monitoring of the thermal power plant of circulating cooling water,software Protel 99 SE is used to design monitoring-node module of the slave.Monitoring-node module has two functions: the first is,to collect the data of sensors such as the tower level sensor for the circulating water,the conductivity senor for suppling water,the temperature senor for suppling water,the conductivity senor for circulating water,the temperature senor for circulating water,the p H senor for circulating water and so on,at the same time,send the data to the PC monitoring software by the serial interface communication protocol,and display them on the PC monitoring software;the second is,to receive the opening of PC monitoring software set for the supply water actuator and the domestic sewage actuator to manipulate the supply water actuator and the domestic sewage actuator.In order to realize the power of circulating cooling water of water-saving management,the Visual Basic 6.0 software and Microsoft Office Access 2003 software are used to design PC monitoring software in this article.PC monitoring software has two functions: the first is,to show up data collected by data acquisition module on time so that draw up the curve to reflect the trends of circulating cooling water;the second is,to analyze the data collected by data acquisition module,with the aid of the soft measurement technology and PID algorithm to calculate the control quantity of the supply water actuator and the domestic sewage actuator,send the data to the monitoring-node module by the serial interface communication protocol,manipulate the supply water actuator and the domestic sewage actuator to realize the automatic control of circulating cooling water.Finally,the future is discussed in this paper.Considering the power plant site environment is bad,and cable connection line is vulnerable to environmental impact,causing signal transmission distortion.With the development of science and technology,wireless network can be used in the future to transmit data,it can avoid the line corrosion due to bad environment,so as to ensure the effective transmission of the signal.