What are the key points of the CNIA’s interpretation of the \"Guidelines for Energy Saving, Carbon Reduction, and Modernization in the Ammonia Synthesis Industry\"? ? ?
Thread Content
The last edit to this post was made by Desert Fish on April 22, 2022, at 15:23. On April 21, the China Nitrogen Fertilizer Industry Association issued an interpretation of the \"Guidelines for Energy Conservation and Carbon Reduction Transformations in the Synthetic Ammonia Industry\", aiming to guide the industry in carrying out such transformations more effectively. Gu Zongqin, president of the China Nitrogen Fertilizer Industry Association, noted that on February 3 this year, the National Development and Reform Commission, in conjunction with relevant departments, issued a notice titled \"Notice on the Release of the ‘Guidelines for Energy Conservation and Carbon Reduction Transformations and Upgrades in Key Sectors of High-Energy-Consuming Industries (2022 Edition)’\", along with the \"Guidelines for Energy Conservation and Carbon Reduction Transformations and Upgrades in the Synthetic Ammonia Industry\". These guidelines outline the directions and technical approaches for energy conservation and carbon reduction in the production of synthetic ammonia from coal and natural gas, as well as in urea production; they are highly targeted and practical. The issuance and implementation of these documents play a crucial guiding role in effectively improving the energy efficiency of the ammonia synthesis industry, reducing carbon emission intensity, and accelerating the industry’s transition toward greener and lower-carbon development. It is said that the main downstream product of synthetic ammonia, namely \"nitrogen fertilizers\", are essential for agriculture and play a vital role in ensuring people’s livelihoods. Ammonia synthesis primarily uses energy sources such as coal and natural gas as raw materials. The production process is complex, requiring high temperatures and pressures; it involves significant consumption of fuel and power, leads to high energy usage during production, and results in a high carbon emission intensity.
Strengthen the demonstration of cutting-edge technology development to drive the low-carbon development of the industry. The Guidelines recommend enhancing the development and application of pioneering technologies and fostering benchmark enterprises. First, carry out research and demonstration on green and low-carbon energy-based ammonia synthesis technology. Encourage research and demonstration on technologies for using green and low-carbon energy sources such as wind and solar power to produce ammonia, in order to provide technical support for the reduction of carbon emissions in the raw materials used in the ammonia production industry. With advances in technological innovation, the price of green electricity will continue to fall, resulting in further reductions in the cost of green hydrogen. As a result, the proportion of green hydrogen used in the production of ammonia will also increase gradually ； Second is to demonstrate dry coal powder gasification technology at 6.5 megapascals and above. Currently, the maximum pressure for dry powder gasification is 4.0 MPa; increasing this gasification pressure can improve the efficiency of gasification and reduce the energy consumption of the facility ； Third, demonstrate and promote the waste boiler or semi-waste boiler process in a timely manner to recover steam generated from the waste heat of high-temperature gas, thereby replacing the gas cooling technology used in the full-quenching process and improving the thermal efficiency of gasification units. Some newly built domestic water-coal slurry gasification units have adopted the \"semi-waste boiler\" technology, which enables the recovery of 650–1100 kilograms of steam per ton of ammonia produced; retrofitting existing plants still requires experimental demonstrations, with this technology to be rolled out once it is perfected. It is necessary to encourage the use of waste boiler or semi-waste boiler processes with independent intellectual property rights, to recover steam generated from the waste heat of high-temperature gas, as a substitute for gas cooling technologies based on full quenching, in order to address the issues related to inefficient energy use and improve energy efficiency.
Accelerate the promotion of mature technologies to drive industry transformation and upgrading. Gu Zongqin pointed out that energy conservation and carbon reduction in the synthetic ammonia industry involve not only energy savings and carbon reduction in the production process, but also those in auxiliary and supporting production systems, such as heating boilers, power supply, and water supply. The Guidelines identify key technologies for the adoption and widespread application of mature processes, focusing on five aspects: energy savings in manufacturing processes, energy savings in major equipment, utilization of waste heat and pressure, reduction of emissions of the three types of waste, and renovation of auxiliary facilities. Energy savings in the manufacturing process. First, choose larger gasifiers to replace smaller ones ； Second, it employs large-scale air separation technology and advanced processes ； Third is the carbon monoxide shift system, which uses isothermal shift in place of adiabatic shift ； Fourth, traditional urea plants using carbon dioxide stripping processes employ high-efficiency trays and counter-current trays, and a medium-pressure system is added to reduce steam consumption ； Fifth is the fully closed-loop urea process using aqueous solutions, which employs technologies such as liquid-phase counter-current heat exchange for urea synthesis ； Sixthly, the system pressure in traditional small and medium-sized ammonia synthesis plants is reduced; the ammonia synthesis pressure is lowered from 31.4 MPa to around 20 MPa, resulting in energy savings of 60–70 kWh per ton of ammonia produced ； Seventh, use high-efficiency ammonia synthesis catalysts to increase the net ammonia yield ； Eighth, optimize the ammonia synthesis process and thermal design, enhance flue gas waste heat recovery and fuel-air preheaters, and add (pre)conversion furnaces, etc. It is also necessary to use 5G, artificial intelligence, big data, and other technologies to optimize process flows, material scheduling, and the precise control of equipment; by enabling interconnection, the intelligence of production lines can be improved, production and operation efficiency can be enhanced, and energy and material consumption can be reduced. Energy conservation for major equipment. Focusing on equipment such as pumps, motors, fans, compressors, transformers, heat exchangers, and industrial boilers, advanced and efficient products and devices are adopted to accelerate the phasing out of outdated and inefficient equipment, thereby improving energy efficiency overall ； Direct drive by steam turbines can be used, or in areas where electricity is cheap, the use of steam drive can be replaced with electric drive to avoid energy conversion losses and improve energy efficiency; applying reflective and heat-absorbing coatings can enhance the thermal efficiency of the first-stage furnace in natural gas systems. Utilization of waste heat and pressure. Optimize the energy recovery network, recover residual pressure and heat, promote the optimization and hierarchical utilization of energy systems, reduce heat losses, and improve the efficiency of energy resource utilization. Utilize turbine units to recover process hydraulic power ； ORC low-temperature hot water waste heat power generation technology and organic Rankine cycle screw expansion power generation technology are employed to recover low-grade thermal energy ； Various new, efficient heat exchangers with low pressure drops, as well as high-performance insulation and cooling materials, are used to enhance the insulation of equipment and pipelines. Reduce the emission of waste gas, waste water, and solid waste. It is highly recommended to adopt the Hebei “Dongguang Model” to transform atmospheric pressure batch fixed-bed ammonia synthesis plants. By using the gas dust removal and cooling technology of \"dry dust removal + indirect cooling,\" the open-type gas cooling system is transformed into a closed-type one, thereby ensuring that there is no waste gas emission from the cooling water system used in the gas production process, which contains air pollutants such as phenols, cyanides, and ammonia. The gas generation furnace was subjected to sealing modifications to improve the operating environment on site, by employing technologies such as fully enclosed vibration screens, bag filters for dust removal, mist systems to suppress dust, sealed discharge of gasified slag, and enclosed transportation of dusty materials; all dust-generating points were sealed or equipped with collection hoods. At the same time, it is necessary to reduce the solvent content in the flash vapor, stripping gas, and CO₂ gas, improve the recovery of decarboxylation solvents, and reduce VOC emissions. Renovation of public auxiliary facilities. Replace the small medium- and low-pressure coal-fired boilers in the enterprise and its surrounding area with large high- and sub-high-pressure coal-fired boilers ； Replace small medium-low pressure blowout gas waste heat recovery units with large high-pressure and sub-high-pressure waste heat boilers ； Efficiently utilize the hierarchical energy use of high-pressure and sub-high-pressure steam generated by coal-fired steam boilers and waste heat (excess heat) steam boilers, first generating electricity using backpressure before supplying the steam for industrial use, and arrange cogeneration in a rational manner.
Impose strict industrial policy constraints to phase out outdated and inefficient production capacity. According to the \"Guidelines for Industrial Structure Adjustment (2019 Edition)\", the processes and equipment that are subject to elimination include: the semi-water gas-ammonia aqueous phase desulfurization method, the atmospheric pressure batch conversion process for producing synthetic ammonia from natural gas, the atmospheric pressure carbon monoxide conversion process as well as the full medium-temperature conversion (high-temperature conversion) processes, the wet desulfurization process without an accompanying sulfur recovery system, fixed-bed batch gasification units that lack facilities for recovering the waste heat from the purge gas, and urea production facilities that do not have systems for hydrolyzing and decomposing the process condensates. Objectives for energy-saving and carbon-reduction upgrades In accordance with the requirements set out in the **National Development and Reform Commission’s ‘Benchmark and Base Levels of Energy Efficiency for Key Sectors in High-Energy-Consuming Industries (2022 Edition)’, the benchmark level for the comprehensive energy consumption per unit of synthetic ammonia produced from high-quality anthracite is 1100 (kilograms of standard coal per ton), while the base level is 1350 (kilograms of standard coal per ton) ； For low-quality smokeless lump coal and briquetted coal, the benchmark level for the comprehensive energy consumption per unit of product is 1200 (kilograms of standard coal per ton), while the baseline level is 1520 (kilograms of standard coal per ton) ； The benchmark level for the comprehensive energy consumption per unit of coal dust (including anthracite and bituminous coal) is 1350 (kilograms of standard coal per ton), while the baseline level is 1550 (kilograms of standard coal per ton) ； The benchmark level for the comprehensive energy consumption per unit of natural gas is 1000 (kilograms of standard coal per ton), while the baseline level is 1200 (kilograms of standard coal per ton).
【Major Chemical Equipment in a Major Country】108 – The First Multi-Nozzle Opposed Semi-Waste-Boiler Gasification Furnace https://bbs.hcbbs.com/thread-3324337-1-1.html (Source: Huahai Chuanliu – Haichuan Chemical Forum Website)
Apply counter-radiation and heat-absorbing coatings to improve the thermal efficiency of the first-stage furnace in natural gas plants