Coke Pit Wall System Improves Long-Term Durability

A coke pit in a refinery’s delayed coking unit had shown signs of deterioration on the pit walls and its integrated maze structure. In addition to corrosion due to chemicals, the walls were cracking and deteriorating due to the impact of front end loaders.

STRUCTURAL TECHNOLOGIES and STRUCTURAL (a Structural Technologies company) were selected to design and install a precast wall system and perform repairs in the maze structure. The improvements were completed in two phases using the same precast system.

For the precast wall system, the projects began with demolition of the deteriorated sections of the existing wall. A leveling curb was formed and dowelled into place, creating a place for the new precast wall sections to rest upon. The precast wall panels were custom engineered and manufactured offsite prior to the turnarounds which significantly reduced installation time. The panels were made with STRUCTURAL TECHNOLOGIES’ proprietary Tstrata concrete material, which dramatically improves the long-term durability and impact resistance of the walls.

General repairs were also made to the coke maze (fines settling pit). Various sections of the maze walls were either raised or lowered to allow a path for optimal water flow and settling of the fine coke particles. Custom designed protective steel Glancing Plates were then installed to act as a barrier from topside crane impact.

Repairs were made during scheduled turnarounds. The West wall was completed in 14 days and the East wall was completed in 21 days.