Overview
ISO 7967-12:2022 is an essential international standard that provides a comprehensive vocabulary for exhaust emission control systems of reciprocating internal combustion engines. Published by ISO, this document classifies and defines key terms related to exhaust emission matter, emission control systems and devices, as well as critical parameters used in emission control processes. The standard serves as a foundation for clear communication and uniform understanding across industries involved in engine design, emission regulation, and environmental compliance.
This second edition updates and expands the terminology to reflect technological advancements and regulatory needs in emission control. It is vital for manufacturers, engineers, environmental agencies, and researchers focused on reducing the environmental impact of combustion engines.
Key Topics
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Exhaust Emission Matter
Definitions of pollutants such as particulate matter (PM), total suspended particulates (TSP), soot, nitrogen oxides (NOx), sulfur oxides (SOx), carbon monoxide (CO), carbon dioxide (CO2), volatile organic compounds (VOC), and others. The standard details their origin, characteristics, and environmental impact.
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Emission Control Systems and Devices
Key components and systems that help reduce harmful exhaust emissions, including:
- Reactive Manifold: Large-volume exhaust manifolds designed to oxidize exhaust gases.
- Thermal Reactors and Catalytic Converters: Equipment using thermal or catalytic oxidation to reduce hydrocarbons and CO.
- Selective Catalytic Reduction (SCR): A system that converts NOx into nitrogen and water using catalysts, often with ammonia or urea as reducing agents.
- Diesel Particulate Filters (DPF) and Gasoline Particulate Filters (GPF): Filters that trap particulate matter to reduce soot emissions.
- Exhaust Gas Recirculation (EGR) and Internal EGR: Techniques that recirculate exhaust gas to lower NOx formation.
- Exhaust Scrubbers: Systems that remove emissions through washing with water or sorbents, commonly used in marine applications.
- Oxygen Sensors (Lambda Sensors): Devices measuring oxygen content to optimize combustion and reduce emissions.
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Parameters for Emission Control Systems
Critical metrics and indicators defined include:
- Space Velocity (SV): The ratio of exhaust gas flow rate to catalyst volume, affecting catalyst performance.
- EGR Ratio (r_EGR): The proportion of recirculated exhaust gas in the inlet air, connected to NOx reduction efficiency.
- Emission Index (EI) and Emission Coefficient: Normalized values representing the emission levels per fuel quantity or unit power output.
- Specific Emission: Pollutant mass flow per power output, useful for engine performance assessment.
- Conversion Efficiency: The percentage of pollutant converted to harmless substances by catalytic converters.
Applications
ISO 7967-12:2022 is crucial for industries and sectors where internal combustion engines are used, particularly those aiming to meet strict environmental regulations. Key applications include:
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Engine Manufacturing and Design
Facilitates consistent terminology for designing advanced emission control systems integrating catalysts, filters, and EGR technology.
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Regulatory Compliance and Testing
Supports authorities and testing organizations in conducting standardized emission measurements and enforcing limits.
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Automotive and Marine Engines
Provides vocabulary essential for developing low-emission engines, including diesel and gasoline engines, marine propulsion, and stationary power plants.
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Environmental Monitoring and Research
Enables scientists and environmental engineers to communicate pollutant characteristics and control methods effectively.
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Aftermarket and Maintenance Services
Assists in identifying and describing emission control devices for repair, replacement, or system upgrades.
Related Standards
To ensure a holistic understanding and implementation, ISO 7967-12:2022 should be referenced alongside related standards such as:
- ISO 8178 Series: Covers measurement methods for exhaust emissions, providing test procedures and emission factors.
- ISO 2710-1: Vocabulary for reciprocating internal combustion engine design and operation terms.
- ISO 8178-3:2019: Test procedures for exhaust gas smoke emissions from compression ignition engines.
- ISO 8178-4:2020: Defines steady-state and transient test cycles for engine applications.
- Global Technical Regulations (GTR) No.11: Establishes harmonized engine emissions standards for non-road mobile machinery.
Adhering to these complementary standards ensures a comprehensive approach to engine emission control and environmental protection.
Keywords: ISO 7967-12:2022, exhaust emission control systems, reciprocating internal combustion engines, emission vocabulary, particulate matter, NOx reduction, catalytic converter, selective catalytic reduction, diesel particulate filter, exhaust gas recirculation, emission parameters, environmental compliance, engine emissions standards