# Microbially-induced carbonate precipitation in coal-associated environments: opportunities and challenges

## TL;DR

This paper reviews how bacteria can help reduce coal dust pollution by forming calcium carbonate, but challenges like cost and scalability remain.

## Contribution

The paper provides a comprehensive review of MICP mechanisms and strategies for coal dust suppression, emphasizing recent advancements in microbial strain selection and delivery methods.

## Key findings

- Urease-producing bacteria catalyze carbonate formation to bind coal dust particles.
- MICP offers low toxicity and ecological compatibility but faces high costs and environmental sensitivity.
- Recent advancements focus on optimizing microbial survival and mineralization efficiency in mining conditions.

## Abstract

Microbial-induced calcium carbonate precipitation (MICP) has emerged as a promising biotechnological approach for addressing coal dust pollution in mining and industrial environments. Among the various biological agents, urease-producing bacteria play a central role in catalyzing urea hydrolysis, leading to the generation of carbonate ions that react with calcium to form calcium carbonate (CaCO3). This biologically formed mineral binds dust particles, enhances surface stability, and reduces airborne pollutant dispersion. While MICP presents clear environmental and structural advantages, including low toxicity, long-term ecological compatibility, and compatibility with natural ecosystems, the underlying mechanisms, particularly the microbial adhesion to coal particles and subsequent mineralization dynamics, remain poorly understood. High production costs, sensitivity to environmental conditions, and lack of large-scale validation have also limited the practical implementation of microbial dust suppressants. This review provides a comprehensive look at the current research on the biological processes and application strategies of MICP in coal dust suppression, emphasizing the role of ureolytic bacteria, carrier systems, and calcium sources. Furthermore, it explores recent advancements in microbial strain selection, additive incorporation, and delivery methods that aim to optimize microbial survival and mineralization efficiency in real-world mining conditions. Future perspectives are discussed to support the development of cost-effective and scalable microbial formulations, paving the way for green and durable solutions in mine dust management.

Diagram illustrating coal dust consolidation using urease-producing bacteria. Initial coal dust consists of loose particles. Microbial treatment introduces bacteria, leading to bacterial adhesion and calcium carbonate formation on cells. Cementation occurs as calcium carbonate binds particles, resulting in a solid, water-impermeable crust.