The process of steel production and manufacturing?

Iron and steel enterprises are the pillar industries to create human wealth. On the other hand, they consume a lot of resources, produce waste and pollute the environment. Facing the overall goal of green manufacturing, it is necessary to optimize the iron and steel production process, so that the iron and steel industry can really improve product quality, improve labor productivity, greatly reduce production costs and embark on the road of sustainable development while maintaining rapid and steady growth of output.

During the Ninth Five-Year Plan period, China's iron and steel industry achieved rapid development, with an average annual increase of more than 6 million tons of steel output. In 2007, the total output of crude steel in China is expected to reach about 480 million tons, an increase of 14% over the previous year, making it a big steel country in the world. However, China is not a strong steel producer, and the gap is mainly manifested in three aspects:

(1) Low level of technical equipment: ① backward technical equipment still accounts for a considerable proportion; ② High energy consumption and serious environmental pollution; ③ The localization rate of major metallurgical technologies and equipment is low, and the advanced production software technology is less mastered.

(2) The product structure is unreasonable and the quality level is low: (1) The ratio of plate to tube in China's steel market demand is 50%, and that in advanced steel producing countries has exceeded 60%; ② Some high value-added steel products can't meet the demand; ③ The product quality is low. The cleanliness of molten steel is low, and the content of harmful gases and inclusions in steel is high.

(3) In terms of production technology, with the changes of composition, oxygen potential and temperature in the production process, the traditional production technology is lengthened, which makes the process investment more and the production cost higher.

The goal of green manufacturing is to minimize the impact on the environment and make the best use of resources in the whole product life cycle from design, manufacturing, packaging, transportation, use to scrapping. The steel industry in 2 1 century can be understood as a collaborative optimization production system-green steel life cycle system, which takes into account the overall energy saving of society and reduces the social environmental load, as shown in figure 1.

Therefore, the green steel production process should have the following three functions:

(1) Manufacturing function of steel products. This is the basic function of steel production, that is, transforming raw materials and energy into steel with good quality, low cost and low environmental load, which can meet the requirements of users.

(2) Efficient energy conversion function. The energy flow input in the process of iron and steel production is not fully utilized by the iron flow, and it needs to be recycled through various conversion technologies, which is equivalent to reducing the social environmental load accordingly.

(3) The disposal and consumption function of mass social garbage. Iron and steel production process can absorb and treat a large number of social wastes, such as: ① treating scrap steel from different sources. Scrap steel is an important renewable resource, which is of great significance for saving natural resources, reducing energy and raw material consumption, reducing environmental pollution, reducing costs and increasing employment. (2) Treating a large amount of waste plastics, including blowing or hot pressing through the tuyere of blast furnace, and loading into coke oven. Injecting 1t waste plastics into blast furnace tuyere is equivalent to injecting 1t hot oil (Germany 1 blast furnace can handle 90,000 tons of waste plastics every year); (3) Disposal of waste tires, that is, cryogenic treatment, crushing, separation treatment or combustion treatment are carried out in an electric furnace by using liquid nitrogen generated by an oxygen generator in an iron and steel plant; (4) To treat social garbage, a large amount of social garbage can be treated in a special incinerator by using the familiar incineration principle and combustible gas of steel mills; ⑤ To treat wastewater and sewage in residential areas, the huge water treatment system of iron and steel works can be used to treat sewage in nearby residential areas. (Source: Manufacturing Information Management)