Ecofriendly Mortar with Paint Sludge Ash

Area of Science:

• Materials Science
• Environmental Engineering
• Civil Engineering

Background:

• Conventional concrete production is environmentally taxing and costly due to cement's high energy intensity and pollution.
• Industrial paint sludge ash (PSA) is a hazardous waste typically destined for landfills, posing environmental and logistical challenges.

Purpose of the Study:

• To investigate the feasibility of using industrial paint sludge ash (PSA) as a partial cement replacement in mortar.
• To evaluate the impact of PSA incorporation on fresh, mechanical, durability, and microstructural properties of mortar.
• To assess the potential of PSA as a sustainable and cost-effective construction material.

Main Methods:

• Mortar mixtures were prepared with PSA replacing cement at levels of 0% to 20% (5% increments).
• Evaluated fresh properties (workability, setting time), mechanical properties (compressive strength, density, ultrasonic pulse velocity), and durability (water absorption, sulfate resistance, porosity).
• Conducted microstructural analyses (SEM, XRD, TGA/DTA, FTIR) to understand property changes.

Main Results:

• Increased PSA content negatively affected workability and setting time but improved water demand for normal consistency.
• Compressive strength, bulk density, and ultrasonic pulse velocity increased with PSA up to 15% replacement.
• Durability properties like sulfate resistance and porosity were enhanced up to 15% PSA, with optimal performance observed at 10% PSA.
• Microstructural analysis confirmed increased mortar densification and improved composition with PSA inclusion.

Conclusions:

• Industrial paint sludge ash (PSA) is a viable supplementary cementitious material.
• Partial replacement of cement with PSA up to 15% enhances mortar mechanical and durability properties.
• Utilizing PSA in construction offers environmental benefits by reducing cement consumption and waste landfilling, while also lowering costs.