Zhejiang Petrochemical Cuts Oil Removal Filter Costs by 35% After a One-Year Field Qualification

Customer Background

Zhejiang Petrochemical Co., Ltd. (ZPC) operates one of China’s largest integrated refining and petrochemical complexes in Zhoushan, Zhejiang Province. With large-scale refining and petrochemical production units operating continuously, equipment reliability and process stability are critical to daily operations.

At this scale, filtration is not a minor maintenance item. Large quantities of filter cartridges are installed across process equipment, and recurring cartridge replacement represents a significant part of long-term maintenance expenditure. Any attempt to reduce filtration costs therefore has to meet two requirements at the same time: meaningful cost savings and proven operating reliability.

For one of ZPC’s oil removal filtration applications, each complete replacement required approximately 1,050 filter cartridges per equipment unit, with a full replacement cycle approximately every three years.

The cartridges had historically been purchased from the original manufacturer. While their performance was proven, the high unit price multiplied across more than one thousand cartridges created substantial recurring procurement costs.

ZPC therefore began evaluating an alternative supplier.

The objective was not simply to find a lower-priced cartridge. The replacement had to provide equivalent filtration performance, dimensional compatibility, mechanical reliability and service life under actual petrochemical operating conditions.

For a critical process application, an unverified replacement was not an acceptable option.

More Than a Standard Replacement Project

Pullner approached the project as a complete product development and reverse-engineering program rather than simply reproducing the dimensions of the existing cartridge.

Original cartridges were obtained for detailed analysis, and the development process continued for more than one year.

Our engineering team evaluated the original product in several areas, including:

• filter media composition and fiber characteristics

• filtration layer construction

• cartridge dimensions and internal structure

• end-cap configuration and sealing

• mechanical strength

• flow resistance and differential pressure behavior

• contaminant retention and filtration performance

The purpose was not merely to manufacture a cartridge that looked identical to the original product.

The real engineering question was whether the new cartridge could maintain comparable filtration performance and operating stability throughout its service life under ZPC’s actual process conditions.

Based on the analysis, Pullner developed a customized cartridge construction and carried out multiple rounds of prototype production, laboratory testing and design adjustment before proceeding to field qualification.

Two Complete Sets Supplied Free for Field Testing

Laboratory results alone were not sufficient to qualify a replacement for an operating petrochemical facility.

To minimize the customer’s risk, Pullner proposed a full-scale field qualification program.

Instead of asking ZPC to place a commercial bulk order based only on laboratory data, we supplied enough cartridges for two complete equipment units free of charge for installation and extended field testing.

The cartridges were installed directly into the customer’s operating system and remained in service under actual process conditions for one full year.

Throughout the trial period, the customer monitored the key operating parameters, including differential pressure development, filtration performance, cartridge integrity and service life.

This extended trial was particularly important. A short-term test can confirm whether a cartridge fits and functions initially, but it cannot demonstrate how the filtration media and cartridge structure will perform over an entire operating cycle.

After one year of continuous field operation, the Pullner cartridges remained stable and met the customer’s process requirements without abnormal pressure development, structural failure or premature replacement.

The field trial provided ZPC with the performance data needed to qualify the cartridge as a reliable alternative to the original product.

35% Lower Procurement Cost After Qualification

Following successful completion of the one-year field qualification, ZPC approved the customized Pullner cartridge for regular procurement.

The final purchase price was approximately 35% lower than the original manufacturer’s product.

With approximately 1,050 cartridges required for each complete replacement, the saving was significant even for a single maintenance cycle. Across repeated replacement cycles and multiple equipment units, the cost advantage becomes a substantial long-term reduction in filtration expenditure.

The customer also gained an additional qualified supply source, reducing dependence on the original manufacturer and providing greater flexibility in lead time, technical communication and future product support.

Project Results

The project demonstrates that replacing an OEM filtration product in a critical petrochemical application should not be based on price alone.

A successful alternative requires understanding the original product, developing the correct filtration structure, validating performance through laboratory testing and, most importantly, proving reliability under actual operating conditions.

For Zhejiang Petrochemical, the result was not simply a lower-cost filter cartridge. It was a technically qualified alternative that delivered proven operating performance together with a 35% reduction in procurement cost and a more flexible long-term supply solution.