# Seawater Mixed with One Part Alkali Activated Material: An Environmental and Cost Evaluation

## TL;DR

This paper explores using seawater mixed with an alkali-activated material as a sustainable and cost-effective alternative to traditional cement.

## Contribution

The study introduces a clinker-free binder using seawater and evaluates its environmental and economic benefits compared to Portland cement.

## Key findings

- The seawater mixed mortar achieves 3-day flexural and compressive strengths of 5.3 MPa and 25.2 MPa.
- The new mortar reduces CO2 emissions by 44.8% compared to commercial cement while maintaining similar costs.

## Abstract

Concrete production is associated with extensive energy consumption and significant CO2 emissions. In addition, tremendous amounts of freshwater are used as a mixing agent. Urgency is increasing to develop sustainable cementitious materials and promote freshwater-saving strategies. An environmentally friendly alternative binder, seawater mixed with one part alkali activated material, is studied. In this work, a cradle-to-gate life cycle assessment was applied to study the equivalent CO2 emission and cost properties of the clinker-free binder. The seawater mixed mortar possesses comparable mechanical properties to Portland cement, with 3 d flexural and compressive strengths of 5.3 MPa and 25.2 MPa. In addition, the mortar developed in this work is of similar cost as commercial cement, but reduces CO2 emissions by 44.8%.