Plastic-Lined Concrete Sewer Pipes for Sulfuric Acid Corrosion
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Concrete sewer systems are prone to premature degradation due to sulfuric acid corrosion caused by H2S gas in wastewater, leading to reduced service life and high costs for chemical-resistant lining solutions, which are often expensive and difficult to implement in complex underground environments.
Innovation Solution
A prefabricated composite concrete element with a premolded corrosion-resistant inner plastic liner, allowing for controlled manufacturing and assembly into a corrosion-resistant sewer system with minimized field labor and expense, featuring a hollow reinforced cast concrete portion and a continuous inner plastic liner that lines the interior and connection details to seal joints against corrosive materials.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Strength
If concrete sewer systems are used, then durability and structural strength are improved, but chemical resistance to sulfuric acid is worsened
Solution Approach 1:
The patent applies composite materials by combining concrete with a plastic liner to create a composite sewer system that leverages the structural strength of concrete while protecting it from chemical corrosion through the plastic lining layer
2Object-affected harmful factors
If polymer concrete is used to replace cement and water, then chemical resistance is improved, but manufacturing cost is worsened
Solution Approach 1:
The patent applies local quality by using conventional concrete for the structural portion where high strength is needed and adding a plastic liner only in the areas exposed to corrosive wastewater, avoiding the need to manufacture the entire structure from expensive polymer concrete
3Object-affected harmful factors
If chemical resistant liner is installed in field after system is built, then corrosion protection is improved, but installation complexity and cost are worsened
Solution Approach 1:
The patent applies preliminary action by pre-attaching the plastic liner to the concrete elements during manufacturing before field installation, so that the liner is already in place and properly positioned when the sewer system is assembled on-site, eliminating the need for complex field installation procedures
4Duration of action of stationary object
If sewer system service life is extended, then durability is improved, but initial manufacturing and installation cost is worsened
Solution Approach 1:
The patent applies parameter changes by modifying the chemical environment around the concrete through the plastic liner, changing the interface between concrete and wastewater from direct contact to lined contact, thereby extending service life without requiring expensive polymer concrete
Data Source
AI summary
A prefabricated composite concrete element for use in a corrosive sewer environment. The concrete element has a hollow reinforced cast concrete portion with at least one end having connection details, a premolded corrosion resistant inner plastic liner. The plastic liner lines an interior of the hollow concrete element and the connection details to provide abutting liner faces in an assembled joint to limit exposure through said joint of said concrete portion to corrosive materials arising in said sewer environment. At least two prefabricated composite concrete elements may be assembled end to end at a joint to form a concrete sewer system. Also disclosed are a method of prefabricating such a composite concrete element.