Durr delivered a complex of RTO treatment plants to the Chinese chemical concern Yisheng Petrochemical

2022: Supply of seven units of Oxi.X R systems

Since 2010, Yisheng Petrochemical Co., Ltd. relies on Durr air purification technologies. The company recently invested in a set of seven regenerative thermal air pollution control systems for a facility in Ningbo, Zhenhai Province, East China. It will provide reliable and cost-effective treatment of large amounts of contaminated exhaust air and will reduce ^CO2 levels. in purified air. The total capacity of the RTO complex with a cleaning capacity of 2.31 million Nm3/h has become one of the largest in the world. For Dürr, this project became the largest in the history of the company, which it announced on February 10, 2022.

Dürr Air Pollution Control Systems for Sustainable CTC Production in China

The Ningbo plant produces mainly purified terephthalic acid (TFA), a starting material in the production of polymer raw materials from which plastic bottles, textiles and food packaging are made. Yisheng Petrochemical is one of the world's manufacturers of TFC. The two most powerful of the seven new production lines of the Ningbo plant produce 3 million tons of TFC per year each. The main problem of TFA production is the partial pollution of exhaust air flows. Dürr again instructed the concern to solve it by ordering the installation of Oxi.X R systems, which operate on the basis of regenerative thermal oxidation (RTO) and effectively remove harmful components from the exhaust air. This will help Yisheng Petrochemical to stop the release of harmful gases into the atmosphere.

In each unit, spent contaminated air passes through a ceramic heat exchanger of a regenerative type, is heated to a temperature close to the reaction temperature and is discharged to the RTO combustion chamber. Here, all dirty substances are converted into harmless components at appropriate combustion temperatures. The purified gases then pass through the ceramic heat exchanger again and give their heat to the ceramic filler. This completes the regeneration cycle.

Dürr put Yisheng Petrochemical "turnkey" seven identical Oxi.X RE regenerative thermal oxidation systems and the corresponding amount of Sorpt.X SW wet scrubbers. Each system consists of a nine-tower Oxy.X RE oxidizer, a downflow scrubber and a cleaned gas exhaust pipe. The capacity of such a system is about 330,000 Nm3/h. The total capacity of seven units is 2.31 million Nm3/h.

One of the world's largest RTO plants with a capacity of 2.31 million Nm ³ /h

After complete oxidation of volatile organic compounds (VOCs) in the PTO units, the gas enters the acid scrubber, where bromine and other halogen-containing compounds are removed from it. Clean air is released into the atmosphere at a height of 60 meters through a pipe on the roof of the scrubber.

In just a few months, Dürr delivered four RTO systems to the Yisheng Petrochemical plant, installed them and put them into operation in July 2021. Three additional units were launched in January 2022. 1340 tons of stainless and carbon steel were used for RTO units and piping systems, more than 200 poppet valves, more than 220,000 units of ceramic blocks and over 150 kilometers of cable.

All Dürr systems of regenerative thermal oxidizers have a rate of destruction and removal of harmful emissions into the atmosphere (UHF) of close to 100%, which meets increasingly stringent environmental standards adopted in China and around the world. In addition, economical and environmentally friendly Dürr RTO systems require minimal maintenance thanks to sealed horizontally located poppet valves and easy access to equipment during inspection.

Energy-optimized Dürr oxidizers can work without additional fuel, and they only need hydrocarbon fuel in the warm-up mode. As RTO systems operating in autothermal mode on spent air energy, will help consumers reduce the carbon footprint.