This case study illustrates the use of chilled water on a joint steel mill and petrochemical plant.
Anshan Steel Company
Anshan, Liaoning Province
The Liaoning province has been home to a large industrial revolution over the last century. There are numerous coal mines, oil refineries, petrochemical plants and steel mills operating on a large scale in this area.
Anshan steel is the largest steel producer in China, with over 100,000 employees on site. The factory produces many basic steel products as well as incorporating a petrochemical plant for coking production and others. The petrochemical plant employs 3,000 people.
Poor heat exchange in the coking plant and other areas leads to inefficient production of processed materials and excess gases plus large volumes of water utilisation.
To ensure heat exchange within the petrochemical division is optimized cold water is needed. For most of the year the ambient temperature of the circulation water is too high. Therefore an additional process is needed to control the temperature of water.
Prior to Wap-Flaro absorption chilling was commissioned to achieve these results. After installation running costs proved too high because of chemical additives needed (lithium bromide) and volumes of water required.
A New Approach
It was decided that WF would be the most economical solution to this problem. In October 2001 WF was commissioned on site.
In this case the steel works have fed 2 process water lines to the WF plant. One line cools down general process water for the petrochemical facilities and the other line is used for cooling liquefied ammonia also within the petrochemical works.
The benefits of operating WF over other methods include:
- Use of very low-pressure waste steam
- Very little additional water usage
- Very low power consumption, as there are no moving parts, only small integral pumps required
- No chemical additives needed only steam and water