Advances in bio-cement production technologies: A systematic review and comparative analysis of MICP, EICP and MAICP processes

The construction sector is under considerable pressure to accept sustainable alternatives to conventional cement. Cement production causes high energy consumption, the depletion of natural resources, and significant greenhouse gas emissions. Bio-cement is developing as a promising building material derived from biotechnology. It capable of improving the performance of soil and concrete while reducing its environmental impact. However, comprehensive comparative assessments of the main bio-cement production technologies remain limited. This study presents a systematic critical analysis of these technologies, focusing on Microbially-induced calcite precipitation (MICP), Enzyme-induced calcite precipitation (EICP), and Microalgae-induced calcite precipitation (MAICP). A review was conducted using the Scopus and Google Scholar databases, based on predefined inclusion and exclusion criteria. This review synthesizes the fundamental mechanisms, production processes, engineering applications, sustainability aspects, and technical limitations of three technologies. It also provides a comprehensive comparison of their environmental, economic, and operational performance. The analysis indicates that MICP is the most studied technology. EICP offers greater uniformity of treatment and increased ease of functionality. While MAICP presents superior long-term sustainability through carbon dioxide sequestration, reduced environmental risks and lower operating costs. The study also identifies the use of waste-derived calcium and urea sources, scaling-up strategies, and field implementation as priority research areas. This study provides an integrated comparative framework that facilitates the selection of the most suitable bio-cement technologies. It finally offers practical guidance for the development of sustainable construction biotechnology and its future industrial applications.