Promote new technologies for flue gas governance and help advance the green low-carbon production of hot blast stove

      As a leading company in the environmental protection industry, Shandong Metallurgical Engineering Co., Ltd. (hereinafter referred to as SDM) has a number of advanced technologies for flue gas governance. In view of the problems of narrow site, complex pipeline and cross operation with blast furnace production that are commonly faced by the flue gas treatment of blast furnace hot blast furnace, the design of Shandong Metallurgical Group Co., Ltd. has innovated on the existing environmental protection plan. In view of the problems of compact site, complex pipelines and cross operation with blast furnace production that are commonly faced by the flue gas governance of HBS, SDM has innovated new ideas on the existing environmental protection plan, making use of SDM sodium based (calcium based) desulfurization technology, SCR denitration technology, high-temperature ceramic fiber tube denitration and dust removal integration technology, etc.
      SDS sodium based (calcium based) desulfurization is a kind of technology that uses desulfurization pipeline reactor and bag type dust remover to jointly desulfurization and dust removal. The sodium based (calcium based) desulfurizer is thermally activated in the flue through efficient dry spraying and bag homogenizing device, and its specific surface area increases rapidly. After full contact with the flue gas, it reacts to purify SO2 and other acidic substances in the flue gas. The sulfur dioxide concentration at the outlet of flue gas after passing through the system can be reduced less than around 30mg/Nm3. This process has the advantages of low investment and operation cost, simple system, stable and reliable operation, convenient operation and maintenance, flexible layout, land saving, flue gas temperature reduction, no waste water discharge, etc. It is the optimal process for hot air furnace flue gas purification project.

      SCR denitration technology is the most widely used flue gas denitration technology at present. NO2 in flue gas and injected ammonia will undergo reduction reaction under the action of catalyst to convert into ammonia and water, so as to remove NOx in flue gas. 
      The HBS flue gas governance adopts the scientific coupling technology of SDS desulfurization and SCR denitration. Desulfurization is first followed by denitration. On the basis of ensuring that the flue gas basically has no temperature drop, it can satisfy the temperature requirements of denitration to the greatest extent, which can ensure the ultra-low emission of flue gas at the outlet.

      High temperature ceramic fiber tube dust removal and denitration integrated technology is a filter element with dust removal and denitration integrated function prepared by loading denitration catalyst with ceramic fiber composite membrane material as the support. First, the dust in the flue gas is effectively removed, and then the catalyst and denitration agent loaded in the multi-dimensional channels inside the ceramic fiber filter membrane support are used to decompose the NOx in the flue gas to achieve the goal of simultaneous dust removal and denitration.

      High temperature ceramic fiber tube dust removal and denitration integration technology can simultaneously achieve efficient dust removal and desulfurization, denitration, deacidification, etc., with stable operation, smaller floor area, longer wear resistance of fiber filter tubes, and more suitable for reconstruction projects with more smaller projects.

      SDM has not only excelled in the technical field, but also has an experienced construction and operation team. They have a clear plan and abilities fight hard. In the complex, tense and urgent HBS flue gas desulfurization transformation project, they are ready and skilled to ensure that they can finish the project construction and operation within the time schedule given by the customer.

      Since the start of the blue sky defense campaign in the steel and iron industry, the design of new flue gas governance technology of SDM has helped the green low-carbon production of HBS. Rizhao Steel complex under Shandong Iron and Steel Group. Ironmaking Plant 2 × The 5100m3 blast furnace hot blast furnace flue gas desulfurization project was successfully commissioned with linkage loads on November 19, 2021, and the commissioning index is far lower than the requirements of the owner's technical agreement for SO2 emission of 30mg/m3 and particulate matter emission of 10mg/m3; The EPC project of flue gas desulfurization transformation of 1 # 3800m3 blast furnace HBS of Laiwu iron and steel group’s replacing the old projects with new one are under construction; The flue gas desulfurization project for the HBS of Hebei Taihang Iron and Steel Group Co., Ltd. 3 # blast furnace close to initiate and eager to finish with due course…

      The power of the army has risen, and the situation is overwhelming. The excellent effect of the SDM supporting HBS flue gas governance project has become a beautiful business card for the owners to promote green development. Adhering to the enterprise philosophy of "learning", "innovation, promotion and leadership", SDM environment conservation designers breaks through the old pattern of technology, dares to innovate, and dares to pursue new technical goals. With the firm belief of perfection as the premise, it helps the green low-carbon production of iron making. We have been dedicated ourselves to green development of iron and steel industry.

SDM’s HICS system helps upgrade the functional manufacturing industry of steel enterprises

      Under the national strategy of carbon peaking and carbon neutralization in advance, intelligent manufacturing has entered a new mode of green, low-carbon and intelligent. On the basis of stable and reliable detection, transmission and control, SDM boasts with a series of advanced and practical intelligent optimization control and intelligent management systems to improve the control level and intelligent decision-making ability in production, quality, safety, management, etc., improve the comprehensive labor productivity and resource utilization, reduce the defective rate of products, operation and maintenance costs, and reduce carbon emissions and pollutant emissions.

      SDM aims to build a green and intelligent metallurgy, energy conservation and reduce emissions, and implement the cost reduction and efficiency increase of enterprises. Since 2012, SDM has independently researched and developed the combustion optimization system of hot blast stove. After several software iterations, 'SDM hot blast stove intelligent combustion system software (HICS)' has been successfully introduced to the market. The software copyright was obtained in 2020, and the system has the advantages of green, low-carbon, intelligent, etc. At present, it has been put into operation on more than 20 blast furnaces at home and abroad. SDM’s HICS system has a variety of functional modules, which can provide customized services for the Clients, mainly including the following functional modules: heat storage prediction module, intelligent combustion module, intelligent furnace exchange module, emergency response module, data statistics and analysis module, etc.

SDM’s HICS system can not only improve the air supply temperature of the HBS, but also effectively reduce the gas consumption, reduce greenhouse gas emissions, realize the unmanned operation of the combustion process, and make the overall operation of the HBS system more stable.

       The heat storage prediction module is helpful to guide the combustion process and ensure the air supply quality. There are many design elements for heat storage of HBS, which are difficult to calculate by real-time data alone which will increase with the service time. The structure of hot blast furnace body will change slowly, which adds more difficulty to theoretical calculation. The prediction module of heat storage capacity is based on the neural network model with self-learning function, collects the change curve of the temperature, pressure, conditions of HBS, gas flow and other data of the HBS, builds a set of initial stave parameters, and calculates the historical data of each point on the stave according to this parameter. Real time heat storage model in HBS is obtained. The module can also continuously optimize furnace parameters. The model is close to the actual HBS condition.

       The intelligent combustion module trains the temperature neural network model by analyzing a large number of previous data. In actual production, the model can combine real-time data to generate the optimal solution of the expected arch temperature, expected arch temperature change rate, expected flue temperature, and expected flue temperature change rate from the heat storage model. With the optimal solution as the input, the ideal gas flow setting and combustion air flow setting are obtained through the indistinct adaptive PID algorithm and the indistinct self-tuning algorithm to ensure the smooth and efficient heating process.

       The emergency response module can solve the complex and changeable problem of HBS operation conditions. In the course of HBS production, the calorific value and pipe network pressure of blast furnace gas fluctuate greatly from time to time. How to give early warning and respond quickly to special working conditions has always been a difficult problem that must be solved in the automatic control process. The intelligent combustion system of hot blast stove integrates a powerful emergency response module.

       When a special working condition occurs, it closely cooperates with the temperature control module to make a variety of reasonable and efficient control measures.

       The HICS system of HBS of 1 # blast furnace in Fangchenggang Iron and Steel Base of Guangxi Iron and Steel Group has been running steadily for one year, improving the control accuracy and reliability of HBS, increasing the air supply temperature by more than 10 ℃, saving energy of gas consumption by 6.8%, and reducing the emission of room temperature gas. At the same time, the automatic control rate of the hot blast stove during combustion is more than 98%, which greatly reduces the labor intensity of personnel, makes the overall operation of the hot blast stove system more stable, and the customized report system meets the user's needs. After the HICS system is put into use, the cost of the Guangxi steel and iron group has been reduced by about 17.4 million yuan every year. By doing so, 105 million cubic meters of gas can be saved, and the annual cost can be reduced by about 8.4 million yuan; if the air supply temperature is increased by 10 ℃, about 3000 tons of coke can be saved every year. About 9 million yuan can be saved accordingly annually; it can reduce 10 tons of carbon emissions.