FGD scrubber support grid

Introduction

To improve FGD system performance, a simple yet effective method is to install column tray to increase contact of gas and liquid. Flue gas absorber grid is to support tray inside absorber. Steel grid not only support and protect internals of FGD scrubber, but also is key factor to influence FGD performance and service life.

Grid material

Popular materials for support grid fabrication are 304, 316L, 2205, 2507, 904L, 1.4529, 254SMO, etc. These materials are different in chemical composition, corrosion resistance, mechanical strength. Selection of material must be made reasonably in consideration of working environment and technical requirement.

• SS304 is good corrosion resistance, it is for common FGD requirement.
• 316L has better resistance to corrosion, it is for harsh situation.
• 904L, also known as N08904 or 1.4539 is excellent for corrosion resistance and mechanical strength.
• 2205, also known as S31803，F51，1.4462, is good in corrosion resistance and mechanical strength.
• 2507, also known as S32750，F55，1.4410, has excellent resistance to pitting corrosion, crevice corrosion and uniform corrosion
• 1.4529 or N08962 has very high resistance to pitting and crevice corrosion in chloridion or sulfur-containing acidic environment. It also performs well in oxidizing and reducing environment. Slightly better than 904L in mechanical properties.
• 254SMO, also known as S31254 or 1.4547, is rich in Mo element, and highly resistant to pitting and crevice corrosion. It is for usage such as seawater application.

Advantages

• Support grid of stainless steel has following features:
• Good resistance to acid and alkali.
• High strength and reliability. Good carrying capacity and deformation resistance.
• Easy cleaning, low maintenance cost.
• Long service life to reduce replacement frequency and economic loss caused by shutdown.