Overview
ISO/TR 27922:2021 is a technical report from ISO that provides an authoritative overview of carbon dioxide (CO2) capture technologies relevant to the cement industry. The document surveys technologies under development, describes their characteristics and maturity, and clarifies the practical boundaries of each approach. It is an informative guide for organizations evaluating options for reducing direct CO2 emissions from cement manufacture.
Scope notes: the report focuses on CO2 capture only - it does not cover CO2 transport, geological storage or utilization.
Key topics
- Sources of CO2 in cement production: process emissions from calcination (about 60–70% of direct CO2 emissions) and combustion emissions from kiln fuels (about 30–40%). Typical flue-gas CO2 contents are in the range of 20%–30%. The report cites process emission ranges (e.g., ~500–540 kg CO2/tonne clinker; ~250–500 kg CO2/tonne cement depending on cement type).
- Capture technology survey: concise descriptions and status updates for technologies including:
- Absorption with amines
- Absorption with chilled ammonia
- Sorbent-based adsorption
- Oxy-fuel combustion
- Pressure swing adsorption (PSA)
- Membrane separation
- Direct separation approaches
- Calcium looping
- Technical boundaries and maturity: technology readiness levels, typical integration challenges, and where technologies are most applicable (e.g., retrofit vs new-build).
- Operational impacts: how capture integration affects energy demand, need for CO2 purification/drying/compression, and implications for plant energy intensity.
- Assessment and comparison: criteria and factors for evaluating capture options, a case-study style evaluation and considerations for retrofitting existing plants.
Applications
ISO/TR 27922:2021 is designed to support practical decision-making and planning in contexts such as:
- Feasibility studies for CO2 capture implementation at cement plants
- Technology selection and comparative assessment of capture options
- Policy development and regulatory planning related to cement decarbonization
- Research, development and demonstration (RD&D) program planning
- Investor and stakeholder due diligence on low-carbon cement projects
Who should use this standard
- Cement producers and plant engineers evaluating CO2 capture solutions
- Energy and process engineers working on kiln systems and emissions control
- Policy makers, regulators and infrastructure planners assessing sector decarbonization pathways
- Technology providers, researchers and investors engaged in CCS/CCU for cement
Related standards
- ISO 27917 - vocabulary for CO2 capture, transportation and geological storage (normative reference)
- ISO/TR 27912:2016 - earlier guidance referenced for capture from cement processes
Keywords: CO2 capture, cement industry, carbon dioxide capture technologies, carbon capture, CCS, calcination emissions, oxy-fuel, amine absorption, calcium looping, membrane separation.