Bangladesh's Energy Backbone:
Hydrocarbon Infrastructure

External corrosion is one of the leading causes of gas pipeline failure globally. Bangladesh's soil conditions — waterlogged alluvial soils, saline coastal soils, high organic content in delta areas, and stray electrical currents from DC railway systems near Dhaka and Chittagong — create a highly aggressive corrosion environment for buried steel pipelines. Cathodic protection (CP) provides a controlled electrical current to the pipeline surface that counteracts the electrochemical corrosion process. There are two main approaches: Impressed current cathodic protection (ICCP) — uses a rectifier to supply DC current through groundbeds; suitable for long-distance transmission pipelines. Sacrificial anode cathodic protection — uses magnesium or zinc anodes that corrode preferentially, protecting the pipe; lower maintenance, suitable for distribution pipelines and storage tanks. Both require proper pipeline coating (FBE or three-layer PE) to achieve economical CP current requirements. Titas Gas and RPGCL specifications require CP systems on all new transmission and high-pressure distribution pipelines. Periodic CP surveys (CIPS, DCVG) are required to confirm ongoing protection.

A Hazard and Operability (HAZOP) study is a structured and systematic technique for identifying potential hazards and operability problems in a process system — examining each part of the process to determine how deviations from the design intent could cause hazardous situations. HAZOP studies are required for: all new gas processing plant designs; LNG terminal detailed designs; petroleum storage terminals above threshold thresholds under OISD-118; and any process modification at existing facilities that alters process conditions, inventory, or protection systems. HAZOP is typically conducted at 30–40% detailed design completion ("PFD/P&ID HAZOP") to allow findings to be incorporated into the design before detailed drawings are frozen. A second HAZOP ("P&ID HAZOP") at 80% design completion reviews the final process and instrumentation design. Urban Engineering can facilitate HAZOP studies, provide the scribe function, and issue HAZOP action-tracking reports that are submitted to regulators as part of the design approval package. HAZOP is now increasingly expected by DoE, BFSCD, and Petrobangla as part of the regulatory approval process for new or modified hydrocarbon facilities in Bangladesh.

Petroleum storage tank design for Bangladesh's delta environment requires specific modifications to standard API 650/IP design practice: (1) Tank foundation design — high groundwater tables and soft soils mean that soil bearing capacity for heavy loaded tanks must be confirmed by geotechnical investigation, with pile foundations (bored cast-in-situ piles) specified where soil conditions cannot support ring wall foundations. Settlement analysis for large tank farms is critical. (2) Flood level and site elevation — tank farms must be raised to a level above the 1-in-100 year flood level plus freeboard. For coastal locations, Bangladesh's official design high flood level maps must be referenced, plus an allowance for sea level rise. (3) Bund design for flood conditions — the secondary containment bund must be designed to retain the product volume while also resisting flood water pressure from outside. The bund drainage system must be designed to handle monsoon rainfall within the bunded area while preventing product escape through drainage outlets. (4) Anchor bolts for tank buoyancy — empty tanks at flood-inundated sites can experience upward buoyancy forces. Anchor bolt design to resist buoyancy is required for tanks below flood level or in areas subject to inundation. Urban Engineering's tank farm designs explicitly address each of these flood-specific requirements, which are often omitted by engineers without Bangladesh-specific experience.