Self-Draining Floating Roof Tilting Deck Drainage
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Full-contact floating roofs in large-scale liquid storage tanks face challenges with vapor control, maintenance accessibility, and weight issues due to liquid accumulation, leading to high costs and safety hazards, as conventional designs require heavy roofs to support the load and prevent liquid from entering the floating members.
Innovation Solution
A self-draining arrangement with a tilting structure and strategically positioned drains allows for a thinner, lighter roof, reducing the assumed live load from 12.5 psf to 5 psf, enabling the roof to be suspended from a fixed roof or the tank shell, and using remotely-activated landing supports to increase tank capacity and safety.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Strength
If a heavy floating roof is used to support liquid load and prevent liquid from entering floating members, then the roof can withstand the load, but the tank volume is reduced and maintenance accessibility is limited
Solution Approach 1:
The invention extracts the supporting function from the floating roof itself by introducing external support structures (fixed roof supports or tank wall supports) that bear the liquid load, allowing the floating roof to be lighter and thinner while maintaining sufficient load-bearing capacity
Solution Approach 2:
The invention introduces adjustable supports that can be remotely positioned to provide temporary load-bearing capacity when needed, and retracted when not needed, allowing the roof to be lighter while maintaining strength when required
2Ease of operation
If manual supports are used to adjust roof position, then maintenance accessibility is improved, but personnel must enter confined dangerous spaces and more weight is added to the roof
Solution Approach 1:
The invention replaces manual mechanical adjustment with remote mechanical or automated support systems that can be adjusted from outside the tank, eliminating the need for personnel to enter confined spaces while providing the same maintenance accessibility benefits
Solution Approach 2:
The invention introduces remotely-activatable supports that can be adjusted without human intervention in the confined space, allowing the system to service itself from the outside
3Loss of substance
If conventional drain openings are provided in the deck, then liquid drainage is improved, but stored product flows up through drains onto the deck causing imbalance and safety hazards
Solution Approach 1:
The invention inverts the conventional drainage approach by placing drain openings at the bottom of the deck rather than the top, allowing liquid to drain from below while preventing stored product from flowing up onto the deck surface
Solution Approach 2:
The invention introduces a sump as an intermediary chamber between the tank bottom and the deck, collecting liquid that accumulates on the deck and channeling it through controlled openings at the bottom for drainage, preventing direct contact between stored product and deck
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
The self-draining design reduces the weight and cost of the floating roof, allowing for a more practical and efficient use of tank volume, safer operations, and reduced maintenance risks by enabling lighter materials and remote adjustments, while minimizing vapor emissions and liquid accumulation.
Implementation Method 1
a buoyant structure that floats on the liquid surface
Implementation Method 2
A self-draining arrangement with a tilting structure and strategically positioned drains allows for a thinner, lighter roof
Data Source
AI summary
A storage tank with a full-contact floating roof is provided with automatic drains that have drain openings that are elevated above the top surface of the deck of the roof. Tilting mechanisms are used to tilt the deck toward the drains, causing liquid on the deck surface to pool at the drains, rising to the level of the drain openings. Cables connected to elevated portions of the tank can be used to tilt the deck from above, and landing supports can be used to tilt the deck from below.