“Blue” cement production with electrified cement kilns

Stanford Energy Research Consortium (SERC)

Background

Cement production accounts for 8% of all CO₂ emissions. Most of these emissions result from calcination, which is the thermal decomposition of limestone (mostly CaCO₃) into lime (CaO) and CO₂. Additional emissions are from burning fossil fuels for heat and transportation. Current carbon capture and sequestration (CCS) approaches applied directly to a conventional cement manufacturing facility are not economically attractive due to capital and energy costs of gas separation, in which relatively pure CO₂ must be separated from a flue gas mixture of air, particulates, and CO₂.

Project Goals

We propose a new class of electrified calcination kiln in which CO₂ from the calcination process is captured at high purity without the need for separations, thereby enhancing the economics of clean cement production. Energy will be provided by green electricity and is inputted into the reactor via high frequency, high efficiency magnetic induction. With magnetic induction, heat is inputted in a manner that is volumetric in nature, does not require electrical contacts, and can be inputted to account for both heat and mass transfer considerations. We anticipate that these concepts have the potential to be extended to the entire cement manufacturing process and to other hard to decarbonize industrial processes that require high-grade heating.

Approach

We aim to perform this research through a theoretical and experimental approach that combines chemical and material science analysis with multi-physics modeling of heat and electromagnetics. First, we will focus on the multi-physics design and manufacturing of different reactor configurations. Next, we will focus on the experimental inductive heating of the reactor to perform calcination to facilitate a detailed materials characterization of the resulting lime phases. We will also conduct a theoretical and experimental analysis of the extension of our concept to clinker production.

Team Members

Jonathan Fan
Jonathan Fan is Associate Professor of the Department of Electrical Engineering at Stanford University. His research lies at the intersection of electromagnetics, materials science, the data sciences, and manufacturing, and it focuses on understanding how electromagnetic waves interact with structured media for utilization in advanced radio frequency and photonic systems applications. His group has pioneered new scientific computing algorithms, based on physics-augmented deep learning, to produce some of the best-in-class optimizers and simulators of photonic systems. His group has also engaged in a significant experimental effort to develop new photonic systems in nanoscale additive manufacturing, metrology, imaging, and ranging. More recently, he has innovated new concepts in the inductive heating of chemical reactors, which are an electrification solution to process heating that can simultaneously reduce reactor footprint and capital costs due to process intensification.

Tiziana Vanorio
Tiziana Vanorio is Associate Professor in Earth and Planetary Sciences, Stanford Doerr School of Sustainability. Her research focuses on studying the properties of rocks and geomaterials under harsh condition of stress and temperature, with emphasis on the physical and mechanical changes that result from solid-fluid chemical interaction. The applications of her research go from geological to engineered processes, including fluids in reservoirs and cementation of natural systems from pozzolanic activity and geopolymerization. Her group is pioneering the design of a geocement — a novel Nature-inspired ‘geomimetic’ cementitious binder that greatly minimizes carbon dioxide emissions and increases serviceability of cement sheath to maintain well integrity behind the casing.