Study On Energy Conservation Optimization And Steam Quality Prediction Model For Steam-Injection Boiler

Steam-injection boiler, which consumes energy mostly in thermal driving, is the key equipment of heavy oil recovery. High energy consumption and low efficiency are ubiquitous at present. Steam quality is the important factor in thermal driving. Improving steam qulity not only can enhance recovery ratio, but also has good protection for oil layer. With the purpose of improving running efficiency of steam-injection boiler and decreasing energy consumption, a set of energy conservation optimization system, which includes steam quality on-line prediction, thermal efficiency and energy efficiency on-line calculation and running condition monitor, was conducted in this paper.The main running parameters of the 3rd steam-injection boiler which belongs to Xianhe oil producing factory in Shengli oil field were investegated, and the data, such as pressure, temperature and flowrate, were collected. Setting up related parameters database and physical property database. Basing on principle of conservation of energy, the inherent relationship and changed regular between presure, temperature, enthalpy and steam quality were analyzed.According to neural network theory, the collected data were taking as prediction sample. A BP neural network model, which makes steam pressure and steam temperature as input layer and makes steam quality as output layer, was developed. As a result, the purpose of predicting steam quality real-time for steam-injection boiler was achieved. The comparison between the predictive result and the measured value showed that this model was of high precision and predictive error below 5%.The energy flow for steam-injection boiler was analyzed by using of heat balance and energy balance analysis method respectively. Analysis models of heat balance and energy balance were built and the charts of thermal loss, thermal efficiency and energy efficiency were described. The weak point of steam-injecting system was discussed and the energy conservation optimization scheme for steam-injection boiler was presented.A set of energy conservation optimization system for steam-injection boiler, which mainly consists of work state monitoring module, steam quality prediction module, efficiency on-line counting module, database management module, system safe warming module and knowledge base management module, was conducted by using of Visual Basic 6.0 and SQL Server 2000. The simulation running results showed that the system can keep steam-injection boiler running with safety and steady, predict steam quality and calculate system efficiency real-time.