Background:
Westlake – Lake Charles, is a chemical plant operating in Lake Charles, LA, specializing in the production of caustics, chlorine, and vinyl chlorides for the manufacture of PVC plastics. Westlake operates six turbines at this site, four of which are turbines with filter houses installed throughout the 1980s.
Westlake – Lake Charles uses the electricity generated from these turbines and the steam from the steam generators attached to the exhausts. The electricity and steam are then used to conduct their chemical processes. Due to the age of the turbine inlets and the corrosive nature of the plant site environment, the site was facing safety challenges as well as a risk of one or more turbine shutdowns.
Problem:
The chemicals that the site produces, mixed with the Louisiana humidity and rain, provide all the right conditions for constant corrosion of steel structures such as the inlet filter systems, even with proper maintenance. Four of the existing inlet filter houses were now approximately 40 years old and experiencing severe corrosion. Most had received numerous previous repairs and patches that were also now failing.
Based on the damage and poor safety condition of the inlets, Westlake – Lake Charles was concerned about the risk of an unplanned shutdown of one of the turbines due to the failing inlet system. This could affect the entire plant operation. Focusing on the most corroded turbine inlet first, and based on Nederman Pneumafil’s assessment of that inlet, Westlake – Lake Charles decided it would require a full replacement. Westlake was open to alternative inlet designs to improve the overall reliability, maintenance cost and efficiency.
Expensive repairs were required as damage to the turbine compressor had occurred. The original inlet filter house, specified by the turbine OEM, was a small, simple 2-stage static filter that did not include features to handle the difficult local environment.
Solution:
The solution was to replace the filter house as soon as possible to ensure continuous, safe operation. The original inlet was a multi-level, vertical cartridge system not designed for pulse cleaning. This was a common design for GE turbine inlets back when originally supplied. Nederman Pneumafil understood the challenges of intermittent heavy dust from the nearby gravel surface access road in the hot summer, accompanied by daily moisture in the early morning hours and a corrosive atmosphere.
Nederman provided Westlake – Lake Charles with the benefits of pulse cleaning filter system vs. static filter systems, while employing an all-synthetic media E10 HEPA grade efficiency filter.
The new inlet design includes common present day cylindrical-conical filter sizes and configurations which match their other two turbine inlets. This allows Westlake to minimize inventory of replacement filters and allow maintenance flexibility to use the same filters in either the new filter house or the existing two inlet filters with the same design filters.
Nederman Pneumafil then designed a horizontal-style pulse cleaning filter house, equipped with materials and paint coatings that could withstand the corrosive, moist environment. Stainless steel was used for the filter mounting tripods, the compressed air headers and blow pipes, and compressed air supply piping. Coordinating closely with Westlake, paint coatings were selected that Westlake has found to work well on their site.
The filter house design also provided the ability to pulse clean off the dust from intermittent road traffic. Given the age of the original filter house and foundation, Nederman Pneumafil had to design around many existing items such as existing electrical cabinets, compressor lines, piping and foundations. Using the same footprint points, a new structural steel system – up to date on the latest structural codes and regulations - was designed and supplied to support the new filter house.
Results:
In August 2023, Nederman Pneumafil provided Westlake – Lake Charles with a new filter house including fully pulseable100% synthetic E10 efficiency HEPA grade filters that would fit into their other filter houses, with a custom pulsing program with specific options for sequences specific to Westlake – Lake Charles’ needs.
Since installation, the turbine has been in continuous operation with a new functional and safe inlet, producing clean air and extending the life of the turbine asset.
