STRATEGIC TYPOLOGY OF ABOVEGROUND TANKS:TECHNICAL CLASSIFICATION, PERFORMANCE, AND OPTIMIZATION OF SELECTION ACCORDING TO THE PRODUCTS STORED.

Core Purpose and Challenges Addressed: The primary goal of this strategic typology is to facilitate the technical classification, performance evaluation, and optimal selection of tanks based on the specific nature of the products they store, ranging from hydrocarbons and biofuels to syngas and water. It addresses the growing demand for energy efficiency, safety, and regulatory compliance in industrial storage. The study aims to fill a critical gap by providing a structured, prescriptive, and performance-driven classification framework for harmonizing reservoir selection criteria. It tackles key challenges such as misclassification, material incompatibility, and underestimation of pressure regimes in tank design. Previous classification efforts often lacked a systemic approach that integrated tank shape, construction material, storage principle (pressure vs. atmospheric), and compatibility with specific energy carriers. The work's objective is to rigorously classify above-ground tanks and propose a method for optimizing selection considering technical and economic constraints, as well as the products stored.

Methodology and Classification: The methodology employs a functional taxonomy that organizes tanks by group, category, class, type, and mode. These classifications are then correlated with crucial performance factors such as strength, capacity, cost-effectiveness, and inspection frequency. The study proposes a standardized typology for Types I to V tanks, with Type V being an expanded category to include emerging composite material solutions.

Above-ground tanks are fundamentally classified according to several criteria:

• Shape: Cylindrical, spherical, rectangular, or liner.

• Storage Principle: Pressure or atmospheric.

• Materials: Steel, aluminum, concrete, composites, plastics.

• Construction Methods: Fixed roof, or external/internal floating roof.

• Standardized Types: Types I to IV, depending on their uses, performance, and applicable standards.

Performance and Optimization Criteria for Selection: Essential criteria when choosing a tank include:

• Leaktightness to prevent leaks and contamination.

• Mechanical resistance to external stresses like wind and seismic activity.

• Emission control to limit losses and environmental impacts.

• Optimal service life and maintenance costs tailored to the stored product.

• Product-tank compatibility, considering chemical resistance, permeability, temperature, volatility, and corrosiveness.

• Pressure/physical state of the stored product.

• Climatic and environmental conditions.

• Ease of inspection and maintenance.

• Projected service life

Tank Types and Standards Compliance: The study provides insights into Types I to V tanks and their corresponding ASME Stamps, which indicate compliance with specific standards for storage tanks, pressure vessels, boilers, and piping. Each stamp corresponds to different ASME sections and standards, signifying adherence to safety and quality regulations relevant to its category.

• Type I Tanks (Cylindrical, very large – fossil fuels, LPG, industrial gases) correspond to U Stamp, S Stamp.

• Type II Tanks (Large, reinforced – water, biofuels, natural gas) correspond to U Stamp, H Stamp.

• Type III Tanks (Cylindrical/spherical – hydrogen, biogas, cryogenic gases) correspond to U Stamp, UM Stamp, PP Stamp.

• Type IV Tanks (Spherical, special gases – hydrogen, ethanol) correspond to U Stamp, UM Stamp, B Stamp.

• Type V Tanks (Small, mobile – samples, light chemicals) correspond to UM Stamp, T Stamp.

Compliance with standards such as API 650, API 653, API 620, EN ISO 16961, EN 14015, ASME BPVC, and NFPA is crucial and guides optimization. Other considerations include local climate, the nature of the product, duration of use, and level of on-site maintenance. The study also notes that typography (clear and concise labeling) is important for improving safety, efficiency, and compliance in tank management, by identifying contents, filling dates, and hazards.

Presentation of the Study: This study will be presented by Hervé YIMGNA MENGOUO at the 1st Annual Aboveground Storage Tank Conference & Trade Show, organized by the National Institute for Storage Tank Management (NISTM). The event will take place on September 24, 2025, at The Westin Long Beach, California.