How is “green” steel made?

Recently, Jiangsu Shagang Group Co., Ltd. was awarded the title of National Metallurgical “Clean Production Environmentally Friendly Enterprise” by China Iron and Steel Industry Association, which marked a significant achievement in Shagang's promotion of energy conservation and emission reduction and implementation of low carbon development strategy.

Continue to increase environmental protection investment in the meager profit

At present, the steel industry has entered the era of low profit, but Shagang has not reduced its investment in environmental protection.

Shagang focuses on the desulfurization of sintering flue gas, and increases the investment in technological transformation of energy conservation and emission reduction, atmospheric treatment, and comprehensive recycling of pollutants. An investment of 150 million yuan has been built into two sintering flue gas desulfurization devices. The high-efficiency and energy-saving rotary spray method is used to desulfurize the sintering flue gas, which can reduce sulfur dioxide emissions by more than 8,000 tons per year. At present, the sulfur dioxide emissions of Shagang's tons of steel have been reduced to 1 kilogram, far below the industry standard of 1.8 kilograms.

So far, Shagang has invested more than 5 billion yuan in energy-saving emission reduction and air-conditioning integrated innovation projects, and completed the development of “new technology for electric furnace hot-packing hot metal energy saving” and “new technology for iron-making one-step iron-making steelmaking”. More than 150 new energy-saving and emission-reducing technologies and technologies, such as large-scale blast furnace blast dehumidification and energy-saving renovation, save 300,000 tons of standard coal per year.

In addition, Shagang has invested tens of millions of yuan to renovate 5800m3 blast furnace ore dedusting, sinter plant car receiving tank dust removal and other projects, can reduce 260 tons of dust per year; invest 100 million yuan to build a new year to deal with steel slag 750,000 tons of heat The slag production line reduces the phenomenon of dustless unorganized emissions. In the sewage treatment project, the second phase of the water reuse project of Shagang Group's 40,000 tons sewage treatment plant is being stepped up. After completion, the water reuse rate will be increased and the chemical oxygen demand (COD) will be reduced by 180 tons.

Let steel companies become converts of clean energy

Shagang has transformed the steel manufacturing process from a one-way linear type of “resources-products-waste” to a circular cycle of “resources-products-renewable resources”. Steel companies are both manufacturers of steel products and converters of clean energy. The consumer of social waste explored and summarized a new model and mechanism for implementing cleaner production, deepening the comprehensive utilization of resources, and developing a circular economy.

Shagang has organically combined energy conservation, environmental protection, clean production and development of circular economy and low-carbon economy, insisted on starting from the source, doing a good job in comprehensive utilization of resources, and implemented 49 major clean production projects. In accordance with the circular economy 3R rule, the small cycle within the branch, the middle cycle between the plants and the large cycle between the enterprise and the society, promote energy-saving emission reduction and comprehensive utilization of resources, and reduce carbon dioxide emissions. Through the implementation of “five major recycling and recycling projects” such as gas, steam, slag, coking by-products and industrial water, environmental protection projects such as smoke (powder) dust control, sintering desulfurization, noise control and hazardous chemicals disposal, Shagang has realized economic benefits and environment. The simultaneous development of benefits.

At present, more than 96% of Shagang's resources are recycled and deeply utilized, and the comprehensive economic benefits created by the low-carbon economy account for about 20% of the total benefits of the company. Among them, Shagang has also built a large number of waste comprehensive utilization production lines such as steel slag-free brick production line and four slag micro-powder production lines with an annual production capacity of over 3.6 million tons. It not only effectively solves the problem of industrial particulate pollutants treatment, but also generates hundreds of millions of circular economic benefits every year through comprehensive utilization of waste, and finds a feasible way to reduce the operating cost of flue gas desulfurization. At the same time, it effectively reduced the emission of industrial dust, and provided an important guarantee for Jinfeng Town, Zhangjiagang City, where Shagang was located, to enter the “National Health Town”.

Shagang has established a professional heating company with recycled steam as its resource. At present, the construction of steam pipe network is 15 kilometers, and more than 20 enterprises have shared steam resources with hotels, bathrooms and Shagang. In 2012, Shagang supplied steam of more than 200,000 tons, which produced significant social and environmental benefits.

It is reported that Shagang is currently stepping up the implementation of the “Twelfth Five-Year Plan” energy conservation plan, aiming to achieve a total energy consumption of 578 kilograms of standard coal per ton of steel in 2015, a comparable energy consumption of 520 kilograms of standard coal per ton of steel, and 3.5 cubic meters of new water per ton of steel. The water reuse rate is 98%, the clean production reaches the first level, and other energy conservation and emission reduction indicators are in the leading position in the same industry. We strive to achieve the higher level of resource conservation and construction of the “Twelfth Five-Year Plan” for the energy conservation and consumption reduction of the Shagang. The mission objectives of an environmentally friendly company.