CSA ANSI/CSA B149.6-15

Preface

This is the first edition of bi-national ANSI/CSA B149.6, Code for digester gas, landfill gas, and biogas generation and utilization.

This Code replaces the CSA B149.6-11, Code for Digester Gas and Landfill Gas Installations.

Below are a few of the major changes:

• Part III was created to address "Digester Gas System for Renewable Energy (agricultural type biogas systems)"


• Several Definitions were added; a few were changed.


• The requirements for the controls for Boilers, Waste Gas Burners, Engines, and Incinerators were taken out of the main text of the code and relocated to an Annex.


• A requirement was modified to ensure that a waste gas burner has a pilot fuel (Natural Gas or Propane only, and not Biogas) that is reliable and is not just sparking the raw main gas.


• A requirement was added indicating that Manometers must always reliably indicate the system pressures, especially during power outages, for plant personnel accessing gas rooms and for trouble shooting purposes etc.


• A requirement was expanded to ensure that a liquid filled manometer, which does not require external power, is only used.


• Incinerator Controls have been removed from the body of the code and put into Annexes, which can be adopted by the Authority Having Jurisdiction (AHJ), if they so wish.


• Controls for Ventilation and Combustion Air have been removed from the body of the code and put into Annexes, which can be adopted by the AHJ, if they so wish.


• Requirements for compliance with piping design codes have been updated to include Canadian and American standards.


• Requirements for compliance underground piping have been updated to include Canadian and American standards.


• The previous edition required instruments to measure the composition of the landfill gas for an explosive mixture but did not specify what to do when it occurred. The system is now required to shutdown when the methane in the landfill gas is between 2.5% and 25% by volume.


• Hazardous areas requirements have been updated to include Canadian and American standards.

This Code was prepared by the Technical Committee on Biogas Generation and Utilization (B149.6), under the jurisdiction of the Strategic Steering Committee on Fuel- Burning Equipment, and has been formally approved by the Technical Committee. This Code has also been formally approved by the Interprovincial Gas Advisory Council and the American National Standards Institute.

In this 2015 edition, major changes and/or additions have been made to the 2011 edition being replaced.

The CSA B149.6 Code Committee, which is responsible for preparing this Code, consists of members of the provincial gas inspection authorities, biogas and waste management entities, certification organizations, and representatives from the Canadian and US federal government . This Code has been formally approved by the CSA B149.6 Technical Committee on Biogas Generation and Utilization Code, by the Interprovincial Gas Advisory Council, and American National Standards Institute.

Scope

1.1 General

1.1.1
This Code applies to the installation of systems for the production, handling, storage, and utilization of digester gas in newly constructed wastewater treatment plants, as well as additions to, and the upgrading of, existing systems.

1.1.2
This Code applies to the installation of systems for the production, handling, and utilization of landfill gas in newly constructed landfill gas systems, as well as additions to, and the upgrading of, existing systems and temporary systems.

1.1.3
This Code applies to the installation of systems for the production, handling, storage, and utilization of biogas in newly constructed biogas systems.

1.1.4
This Code applies to piping systems in which the maximum operating pressures for piping used in digester systems, landfill gas systems, or biogas systems do not exceed 860 kPa for piping installed outdoors or 450 kPa for piping installed indoors.

1.1.5
This Code applies to the safety aspects of the operation and maintenance for handling, storage, and utilization of digester gas in wastewater treatment plants and landfill gas at landfill sites or biogas in biogas systems.

Note: This Code does not apply to substrate storage, long-term digestate storage, or pilot scale and research digesters in biogas systems.

1.1.6
This Code applies to existing digester gas and landfill gas systems where, in the opinion of the authority having jurisdiction, a hazard or potential hazard exists.

1.1.7
Within the scope of Clauses 1.1.1 to 1.1.5, there may be provisions not covered in this Code, in which case the applicable provisions of the authority having jurisdiction are to apply.

1.1.8
Renewable natural gas is excluded from this code.

1.2 Scope of each Clause of this Code

1.2.1 General

Each Clause of this Code shall be used with other applicable Clauses.

1.2.2 Clause 1 - Scope

Clause 1 contains the scope of this Code.

1.2.3 Clause 2 - Reference publications

Clause 2 contains the reference publications used in this Code.

1.2.4 Clause 3 - Definitions and abbreviations

Throughout this Code certain words appear in bold italic type. These are the words which for the purpose of this Code have been defined to ensure understanding of their intended meaning.

1.2.5 Clause 4 - General requirements for digester gas systems

Clause 4 contains general requirements for appliances, accessories, components, and equipment, quality of work, personnel qualifications, control of sources of ignition, compliance with other codes, and prohibited practices.

1.2.6 Clause 5 - Installation requirements for appliances and equipment on digester gas systems

Clause 5 contains basic requirements pertaining to the installation of appliances and equipment with respect to their suitability for use, connections, clearances, accessibility, etc.

1.2.7 Clause 6 - Installation requirements for specific types of appliances and equipment on digester gas systems

Clause 6 contains minimum requirements for compressors, boilers, waste gas burners, stationary gas engines, and incinerators.

1.2.8 Clause 7 - Air for combustion, venting, and ventilation in digester gas systems

Clause 7 contains minimum requirements for the air to be used for combustion, venting, and ventilation of appliances and equipment.

1.2.9 Clause 8 - Piping and tubing systems and fittings in digester gas systems

Clause 8 contains minimum requirements for the material, size, pressure, location, practices, protection, purging, and identification of piping and tubing systems and fittings.

1.2.10 Clause 9 - Digesters and gas storage tanks Clause 9 contains requirements for the tanks used in the generation and storage of digester gas.

1.2.11 Clause 10 - Building and building services for digester gas systems

Clause 10 contains requirements for compressor rooms, boiler rooms, hazardous areas, and combustible gas detection equipment.

1.2.12 Clause 11 - Testing hazardous areas and digester gas systems

Clause 11 contains requirements for testing digester tank roofs and piping systems.

1.2.13 Clause 12 - Electrical requirements for digester gas systems

Clause 12 con