摘 要 随着国家对于企业外排烟气环保标准的不断提高，为了解决钼产业链中焙烧钼精矿所产生的低浓度冶炼烟气的达标排放问题，金钼股份硫酸厂于2007年新建了一套配气制酸生产线，同时配套建设一套装机容量为6MW的汽轮发电机组通过硫酸生产线余热回收发电。整个生产过程控制大部分通过DCS控制系统进行监控，系统自动化程度相对较高，但是由于余热锅炉DCS控制系统控制方案存在不足致使生产线正式投产后多次出现锅炉泄漏等重大设备事故，而绝大多数事故均与余热锅炉操作控制有关。不仅严重影响了公司整个钼产业链正常运转，还造成了重大经济损失和环保风险。 本课题通过对硫酸厂因余热锅炉操作控制问题导致的事故进行剖析查找出事故原因主要是锅炉汽包液位控制不当造成的，而汽包液位难于稳定有效调节的直接原因就是汽包的“虚假水位”。有鉴于此，为了有效抑制“虚假水位”实现汽包液位稳定可靠调节控制，杜绝与锅炉操作控制相关的重大设备事故再次发生，对硫酸厂余热锅炉特性进行了深入研究分析并开展运行控制参数分析计算，进而基于生产系统现状需求和锅炉现有DCS控制系统平台通过大量理论分析与推导，制定出了合理可行的串级三冲量锅炉给水自调改造解决方案并在经过Simulink仿真软件包仿真验证后予以现场实施。 新制定的锅炉汽包液位自调控制改造方案修正了原设计及施工过程中关于锅炉汽包液位DCS自调控制系统存在的不足，使得“虚假水位”得到了有效抑制，汽包液位成功实现了在工艺指标允许范围内长周期稳定可靠的自动调节控制。彻底消除频繁导致锅炉及配套汽轮发电机组事故的问题隐患，大大提升了锅炉DCS监控系统的自控水平和可靠性。不仅使得汽包液位自调控制稳定可靠，降低锅炉岗位操作人员工作强度，提高工作效率，还确保了锅炉的安全、稳定、高效经济运行。

Abstract With the continuous improvement of the National Environmental Protection standards for external exhaust flue gas of enterprises, in order to solve the problem of the emission of low-concentration smelting flue gas produced by roasting Molybdenum concentrate in the Molybdenum industrial chain, the Acid Plant established of JDC a new set of air distribution in 2007. At the same time, a turbo generator set with a capacity of 6MW was built through sulfur. Acid production line waste heat recovery power generation. The control system of the whole production process is monitored by DCS control system, and the automation degree of the system is relatively high. However, due to the lack of the control scheme of the DCS control system of the waste heat boiler, many accidents such as the leakage of the boiler and so on appear many times after the production line is formally put into operation, and most of the accidents are controlled by the operation of the waste heat boiler. Of It not only seriously affected the normal operation of the whole molybdenum industry chain, but also caused significant economic losses and environmental risks. Through the analysis of the accident caused by the operation control of waste heat boiler in sulphuric acid plant, the main cause of the accident is the improper control of the liquid level of the boiler drum, and the direct cause of the difficult and effective regulation of the drum liquid level is the "false water level" of the drum. In view of this, in order to effectively suppress the "false water level" to realize the stable and reliable control control of the drum liquid level and eliminate the major equipment accidents related to the operation control of the boiler again, the characteristics of the waste heat boiler in the sulphuric acid plant are studied and analyzed, and the operation control parameters are analyzed and calculated, based on the status of the production system. Through a large amount of theoretical analysis and deduction, the existing DCS control system platform of the boiler and the boiler has worked out a reasonable and feasible solution for the water supply self adjustment of the cascade three impulse boiler and implemented it in the field after the simulation and verification of the Simulink simulation software package. The new scheme of self adjusting control of boiler drum liquid level correction modified the shortcomings of the boiler drum liquid level DCS self adjusting control system in the original design and construction process, which made the "false water level" effectively suppressed, and the drum liquid level successfully realized the long and reliable and reliable automatic regulation and control in the range of the technical index allowable range. System. Thoroughly eliminate the hidden trouble that frequently causes accidents of boiler and matching turbogenerator unit, and greatly enhance the automatic control level and reliability of boiler DCS monitoring system. It not only makes the self adjusting control of the drum liquid level stable and reliable, reduces the working strength of the boiler operator and improves the working efficiency, but also ensures the safe, stable and efficient economic operation of the boiler.