Novolex

PREVIOUS SITUATION

The existing chiller yard consisted of 5 Trane Air cooled chillers; 2 – 100-ton RTAA’s, 1 – 125-ton RTAA, 1 – 200-ton RTAC and 1 – 225-ton RTAC. These chillers had outlived their useful lives with repairs, reliability and efficiency being the main issues.

  • The 2 - 100-ton chillers were not functioning and need to be replaced.
  • The two RTAC were running on one circuit and the 125-ton chiller kept losing compressors. 
  • Repair costs exceeded operating budgets and repair parts were not available in a timely manner.
  • Production cycles were down due to lack of process cooling and $’s was being wasted. 
  •  The efficiency of existing chillers and reduced production was making it impossible to meet current operating budgets.
  • Envelope temperature on the process floor made it difficult to maintain production due to high levels of humidity and the stagnant air made the work environment impossible to retain employees.

Desired Situation

The owner wanted, above all else, a chiller system that would be reliable and ensure continuous production with minimal downtime. The plant design had to functional, reliable, efficient and be used to provide envelope control for process improvement.

The requirements and advantages of the redesigned chiller yard:

  • Built in redundancy.
  • Reliability with minimal downtime using reliable vertical screw chillers and MCS controls.
  • High efficiency.
  • Expansion for OSA control and process back up
  • Better utilization of space 
  • Reduced maintenance cost

Recommendations and Final Solution

Applied Climate Solutions provided a design/build replacement to replace the existing 5 chillers with two with 2–470-ton Dunham Bush hi-efficient air-cooled chillers. The system ties into two process loops and provides additional cooling for the OSA system. The chillers are the AVX-B variable speed vertical compressors with low sound option. The chillers are sized for 100% redundancy utilizing the redundant chiller to pretreat the OSA. Since reliability is a key factor, the owner opted for the variable speed vertical twin compressor configuration in each chiller.

With the desire to eliminate down time and improve serviceability the coils are spine fin and the heat exchangers are shell and tube with removable heads for easy serviceability. The recommendation included efficiency upgrades to variable speed compressors, EC motor condenser fans, EEV’s and built in economizer for increased capacity and efficiency.