A environmental project unique in all respects has been launched in the Arctic, as stated by Sergey Dubovitsky, Senior Vice President of Norilsk Nickel, during the commissioning of the first stage of the Sulfur Program at the Nadezhdinsky Metallurgical Plant on October 25.
In order to implement this large environmental project, a partial reconfiguration of metallurgical production was implemented and sulfur dioxide recycling facilities with the necessary infrastructure were built.
The volume of investments exceeded 120 billion rubles, the construction lasted more than three years. Up to 4000 workers and specialists were present at the facility around the clock, more than 400 units of special equipment were used. As a result, 500 jobs were created.
"Firstly, this project is unique in terms of scale. It is unique for mining and metallurgical industry not only in Russia but also worldwide. The scale of investments in the main technological complex alone is more than 180 billion rubles, of which more than 120 billion rubles has already been invested. And this is only the main technological complex, not counting related projects," Dubovitsky said.
Secondly, according to Dubovitsky, the Sulfur Program is a unique project in terms of complexity, consisting of many elements. In particular, a new Mokulaevsky limestone quarry was commissioned specifically for the Sulfur Program. A dedicated railway line has been built, all the necessary infrastructure has been created, and railway wagons were purchased.
"And, of course, a huge technological complex has been created [to support the project]. It occupies the area of seven football fields with technological processing units, workshops, and a rather impressive hydraulic engineering structure which is the gypsum storage facility. There is a new energy and logistics infrastructure created specifically for the implementation of this project," Dubovitsky continued.
In addition, according to him, the Sulfur Program is a unique project in terms of environmental impact reduction, since it will make a decisive contribution to the implementation of the nationwide task of the Clean Air project.
The conditions in which the Sulfur Program was implemented are also unique. Dubovitsky recalled that the first construction contract was signed in February 2020 but the COVID-19 pandemic, quarantines and logistical restrictions hindered its implementation. And at the beginning of 2022, many foreign suppliers of equipment, in fact, refused to fulfill their contractual obligations and the company had to find new technical solutions and select comparable items on the go.
At the moment, more than 90% of the equipment and materials on the project are of domestic production, as well as partially produced by "friendly" nations.
"There are still many tasks ahead to be solved, to reach the design capacity, and next year to complete the second stage of the Sulfur Program in order to achieve the full effect of this project," said the senior Vice president of Norilsk Nickel.
Meanwhile Yevgeny Vaganov, scientific director of the Siberian Federal University and Academician of the Russian Academy of Sciences, noted that the introduction of environmentally friendly technologies is of great importance nowadays.
"The launch of the Sulfur Program is a historic event for the city [of Norilsk], for the region, and for Russia as a whole. Norilsk was once focused on production, and ecology lagged behind, but now we are witnessing a breakthrough associated with the implementation of a complex environmental project, which has no comparable examples in the world in terms of scale. I was impressed by the fact that the company designed and built a unique production facility, the final product of which is an environmentally neutral substance suitable for use in construction, for example. The development and implementation of so-called nature-like technologies are very important for the environment, and the Sulfur Program is one of the most successful examples of the implementation of such technology," he said.
Norilsk Nickel's largest environmental project is aimed at achieving sulfur dioxide utilization rates at the level of the world's best practices and radically reducing sulfur dioxide emissions with an improvement in the environmental situation.
The essence of the Sulfur program of Norilsk Nickel is represented by two technologies – the production and neutralization of sulfuric acid.
The first is the conversion of sulfur dioxide into sulfuric acid. Waste gases with a high content of sulfur dioxide are routed from the Nadezhdinsky Metallurgical Plant's smelting unit through large-diameter pipes to the wet cleaning department. Here they are cooled and cleaned of impurities on wet electrofilters.
Then, the gases already purified to the required level are sent to the mixing tower, where they are diluted, and sent to the sulfuric acid production unit in the drying-absorption and contact-compression compartments.
Drying towers, contact devices, heat exchangers, absorbers and other technological equipment are involved in this process.
After the drying tower, the dried gas is sent to the contact node, where sulfur dioxide is oxidized into trioxide, which then goes to the absorbers, where sulfuric acid is produced directly. It is collected and sent to a separate warehouse for subsequent neutralization.
"The second technology meets the first [at this stage]. Limestone mixed with water is used to neutralize sulfuric acid. It is obtained by crushing limestone mined at the Mokulaevsky quarry and delivered to Nadezhdinsky by rail. Here, the material passes through the conveyor belt into the crushing compartment to be mixed with water. In this unit there are mills, classifiers and mixing devices. Limestone goes through the grinding process, water is added and then the mixture is obtained," said Senior Manager of NN Development LLC Alexey Kunaev to sgnorilsk.ru.
The quarry will be able to produce up to 6.5 million tons of limestone per year (2.5 million tons of which are routed to Nadezhdinsky, the same amount in the future will be sent to the Copper plant and 1 million tons for a Cement plant and construction).
"This year we will need about 1.8 million tons of limestone for the first stage of the project. About 50,000 tons have already been mined, crushed and stored for shipment here. In total, the reserves at Mokulaevsky should be enough for 49 years of operation," said Andrey Sergeyenkov, head of the sulfur projects group at NN Development LLC.
The next step in the process utilizes the two products, Sergeyenkov adds. Sulfuric acid and limestone water mixture are combined in reactors. The gypsum pulp obtained as a result is sent through the pipes of the hydraulic transport system to the gypsum storage facility. There the gypsum settles, and the clarified water is reused in the further production of limestone and water mixture. This completes the complex process of sulfur dioxide neutralization.
The company still considers options for the further use of the resulting gypsum in various activities and in different areas. It can be used in construction or in laying mixtures in mining.
"The uniqueness of the project lies in the fact that there is an incredible gigantic scale of production and very difficult operating conditions of the equipment. It is difficult to find such a mixture of two technologies on such a scale and equipment configuration in world practice," explained Alexey Kunaev.
Norilsk Nickel's environmental project was highly praised by the Federal Service for Hydrometeorology and Environmental Monitoring.
"The Sulfur Program is part of the federal Clean Air project of the national Ecology Project and is an important element of the socio-economic development of Siberia," said Vadim Petrov, State Secretary of the Ecological Chamber of Russia and Chairman of the Public Council at Roshydromet.
He called the Sulfur Program the most unique and largest environmental project in Russia.
The full commissioning of the Sulfur Program will make it possible to reduce sulfur dioxide emissions by the company's enterprises in Norilsk by 45% from the base 2015 level towards 2025.
Alex Shishlo for Rough&Polished
