世界上规模最大的400万t/a煤基费托合成装置，于2016年11月首次试车运行,该装置采用中科合成油的中温费托合成技术建设，核心单元由8个年产50万t费托合成中间产物的浆态床反应器组成，具有设备系列多、规模大、配置复杂的特点。装置运行过程中暴露出高温油气分离效果差、产物汽提塔设计不合理、费托合成反应器与脱碳单元难匹配等突出问题。通过近2 a的技术攻关和优化改造，解决了大部分问题，实现了装置安全稳定运行。通过增加旋风分离器数量，减小其尺寸，提高入口油气气速，显著降低了高温油气中夹带的催化剂颗粒量，避免了换热分离器的堵塞，实现了重油、轻油和和合成水的有效分离;从控制换热分离器中重油温度和提高汽提塔重油进料温度两个方面进行优化操作。将换热分离器中水的平衡分压控制在0.26~0.32 MPa时，确保合成水不凝结，且轻质油中不含重油。同时将换热分离器底部重油温度控制在128~135 ℃。另一方面，确保重油进入汽提塔的温度不小于170 ℃，实现了汽提塔热量再平衡，塔底釜温维持在200 ℃以上，确保了汽提塔运行的安全性;将各费托合成反应器出口压力控制在2.3 MPa，并控制各循环气压缩机一段进气量，和提高压缩机二段进气量实现操作调控送入脱碳装置的合成尾气量，提高了费托合成反应器与脱碳单元匹配性，提高了系统运行的稳定性。装置运行标定结果为:CH₄选择性为2.90%，C⁺₃选择性平均值为96.1%，C⁺₅选择性达到92.8%，吨油消耗合成气5 686 m³(标准状态)，吨产物副产4.5 t中压蒸汽和1.1 t合成水，基本达到设计指标。

The world’ s largest coal-based Fischer-Tropsch synthesis plant with a capacity of 4 million tons per year was industrially applied by Ningxia Coal Industry,China Energy Group in 2016. The medium temperature Fischer-Tro- psch synthesis technology from Synfuels China Technology Co. ,Ltd. was first in a large-scale application. The Fischer- Tropsch synthesis unit consists of eight slurry bed reactors with an annual output of 500 thousand tons of intermediate products,and is characterized by many series of synthesis reactors,a large scale and complex configuration. Many problems were exposed during the test run of the plant,such as a low separation efficiency of high temperature oil gas and an unreasonable design of intermediate product stripper. Most of the problems have been solved,and the safe and sta- ble operation of the plant has been realized through technical improvement and optimization in the past two years. The amount of catalyst particles in high-temperature oil-gas is significantly reduced by increasing the number of cyclones, reducing their size,and increasing the inlet oil-gas velocity. The blockage of heat-exchange separator is avoided,and the effective separation of heavy oil,light oil and synthetic water is realized. The optimization operation is carried out from two aspects. One is to keep control on the temperature of heavy oil in the heat exchanger separator. The other is to increase the temperature of heavy oil feed in the stripper. When the balanced partial pressure of water in the heat-ex- change separator is controlled at 0. 26-0. 32 MPa,the synthetic water will not condense and the light oil will not con- tain heavy oil. At the same time,the temperature of heavy oil at the bottom of heat-exchange separator is controlled at 128-135 ℃ . On the other hand,the temperature of heavy oil entering the stripper is not less than 170 ℃ ,and the heat rebalance of stripper has been realized. The temperature of bottom of the stripper keeps at above 200 ℃ ,and the safety of the stripper operation can be ensured. The outlet pressure of each Fischer-Tropsch synthesis reactor is controlled at 2. 3 MPa,and the intake volume of the first section of each cycle gas compressor is controlled. The intake volume of the second section of the compressor is increased to realize the operation regulation of the synthetic tail gas volume to the de-carbonization device. These means improve the matching between the Fischer-Tropsch synthesis reactors and the de-carbonization unit,and the operation stability of the system. The operation results of the plant show that the average selectivities to CH4 ,C+ and C+ are 2. 90% ,96. 15% and 92. 8% ,respectively,and the average syngas consumption per ton oil is 5686 standard m3. The by-product steam with 2. 8 MPa is 4. 53 tons per ton of the Fischer-Tropsch inter- mediate products,and the synthetic water is 1. 12 tons per ton of the Fischer-Tropsch intermediate. These results show that the design target has been achieved.