Ultra-Large Benchmarking 60,000Nm³/h VPSA-O2 Plant Project

The VPSA oxygen unit (62,500Nm³/h, 80%) designed and constructed by PKU Pioneer for Valin Lianyuan Steel was officially put into production at the end of March 2021. The project is divided into two phases (the first phase with an oxygen production capacity of 25,000Nm³/h and the second phase of 37,500Nm³/h), which is the largest VPSA oxygen generation unit in China. It would greatly support the “10 million tons of superior special steel” capacity optimization project of Lianyuan Steel.

Before the commissioning, Lianyuan Steel could only rely on purchasing liquid oxygen to meet its production needs. During peak production periods, the daily amount reached 450 tons with the price as high as ¥1300/ton, which almost accounts for all the liquid oxygen output of Hunan Province. And when the supply was insufficient, the liquid oxygen even had to be dispatched from Guangxi, Guangdong and Fujian Province. Under the huge supplying pressure of liquid oxygen for the user, PKU Pioneer actively responded to the customer’s demand. Prioritizing the customer’s benefits, PKU Pioneer made every effort to promote the construction and the project was finally delivered 10 days in advance. With the oxygen unit fully reaching the designed capacity, the local liquid oxygen price once dropped to ¥800/ton and Lianyuan Steel successfully achieved the low-cost oxygen supply balance for 10 million tons of steel production capacity, thus completely resolving the long-pending oxygen supply and demand contradiction. In addition，a part of the cryogenic air separation capacity was successfully transferred to the converter, thus enabling a favorable timing for the air separation shut-down for maintenance.

As the initiating unit of the EPC project, leading the designing units and the construction & installation companies, PKU Pioneer is fully responsible for the overall designing, supply of the complete set of equipment, installation and debugging, construction management, instrument control software programming, systematic commissioning for oxygen production as well as operation optimization, etc. On the premise of ensuring the oxygen equipment meets the design indicators, PKU Pioneer got down to solve the problem of tight construction work from various aspects and worked as carefully as possible.

According to the comprehensive power consumption since the VPSA oxygen plant went into operation, the operating cost is less than ¥0.2/m3 (100% pure oxygen), saving more than 30% of the oxygen usage cost. In addition, by increasing the oxygen enrichment rate of the blast furnace, the output was increased by 500,000 tons, the coke ratio was drastically reduced during the same period, and the coal gas power generation was increased. In sum, the annual comprehensive profits were remarkable.

The successful completion of Lianyuan Steel’s 60,000Nm3/h VPSA oxygen generation project will positively promote the application of ultra-large-capacity VPSA oxygen production technology in steel industry in the world. In the future, VPSA oxygen generation technology, serving as an effective means for the blast furnace oxygen enrichment, will attract more and more 10-million-ton steel mills to make it an important component of their energy system, and strongly supplement the steel mill’s oxygen supply with significant advantages such as short construction period, low cost, and fast effects.