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A Record of the Efforts to Reduce Energy Consumption in the Fertilizer Production Unit of Ningxia Petrochemical Company / Author/Source: Sinochem News Network / Date: 2022-11-16 / Clicks: 23. “Since the start of mutual supply of fuel gas between refining and chemical production units, in just October alone, the natural gas consumption per ton of ammonia produced decreased by 11.44 standard cubic meters, while the overall energy consumption dropped by 0.39 gigajoules. This contributed to ensuring stable operations of the plant during winter.” ”Recently, Xu Chengbao, a technician from the First Fertilizer Department of Ningxia Petrochemical Company, did some calculations while comparing production targets. Ningxia Petrochemical Company’s 45/80 domestic large-scale fertilizer production plant is a facility for manufacturing fertilizers using natural gas as raw material. To ensure the plant can continue operating during the winter months, the Fertilizer Department of Ningxia Petrochemical Company took comprehensive measures and planned in advance, employing a range of strategies such as technical innovations, process optimization, and creative solutions to reduce natural gas consumption and achieve energy savings in the use of raw gas. Technological innovation reduces energy consumption. The first fertilizer production department of this company uses technological innovation as a driving force for improving quality and efficiency; in collaboration with the Science and Technology Department, it carried out innovative efforts to implement technical upgrades that enabled the use of domestic separation membranes in the hydrogen recovery unit of the ammonia synthesis plant, thereby increasing the hydrogen content at the output of the membrane system. Through actual operation and optimization adjustments, the purity of high-pressure hydrogen recovered increased to around 87%, while the purity of low-pressure hydrogen rose to about 75%. The natural gas consumption per ton of ammonia was significantly reduced. Furthermore, by implementing an advanced process control system (APC), the department has reduced the variation margins of key parameters such as the outlet temperature of the first-stage furnace, the water-to-carbon ratio, the temperature of the catalyst bed in the synthesis tower, and the urea ammonia-to-carbon ratio by over 50%. To date, the operational stability rate of the fertilizer production plant has reached 99.75%, achieving a target of zero frequent alarms, which lays a foundation for energy conservation and stable supply of the plant during winter. Joint efforts boost efficiency: This year, fertilizer and refining facilities have carried out joint initiatives to introduce the fuel gas from refining processes into the fuel gas system of the first-stage conversion furnace, thereby replacing some of the natural gas used as fuel and reducing the natural gas consumption per ton of ammonia produced. Starting from May, as the supply of refining fuel gas increased, the amount of fuel gas used in the furnace also increased; as a result, the natural gas consumption per ton of ammonia continued to decline and remained below 1,065 standard cubic meters. By achieving integrated management of refining and chemical processing, the goal of reducing natural gas consumption and ensuring a stable supply during winter was met. To date, the fertilizer plant has utilized a total of 16.81 million cubic meters of refinery fuel gas, which has helped alleviate the shortage of natural gas available for use in the plant during winter. Optimizing operation to reduce consumption: The company’s Fertilizer Department 1 focused on optimizing the operation of the equipment, carrying out initiatives to address challenges through targeted efforts; task forces were established to reduce the oxygen content in the furnace chamber to 1.5%–2.0% and adjust the water-to-carbon ratio to 3:0, thereby achieving the goal of saving 1,500 standard cubic meters of natural gas per day. By resolving the sticking issue with the high-pressure steam pressure relief valve PIC8023B and adjusting the balanced steam network, they reduced the discharge valve on the medium-pressure steam network from 15% to around 5%, which allowed them to save about 10 tons of steam per hour and thus reduced their natural gas consumption. In addition, with a focus on reducing energy consumption in the facilities during winter, the Fertilizer Department has defined detailed metrics related to natural gas consumption per ton of ammonia produced, ammonia output, urea output, operational stability, alarm frequency, and water consumption per ton of urea. It has launched efficiency-improvement competition initiatives to continuously enhance the operational capabilities of these facilities, resulting in record-low levels of energy consumption such as natural gas usage per ton of ammonia and water usage per ton of urea. This has laid a solid foundation for the facilities to carry out production activities throughout the winter.