Biogas Cover Equipment

Engineered protection, access, and pressure management for digester covers.

What It Is & How It Works

Biogas cover equipment encompasses the mechanical and monitoring devices installed at the interface of fixed and floating anaerobic digester covers, including egg-shaped digesters and low-pressure gas holders. These instruments manage operating pressure and vacuum, prevent flame flashback, provide safe personnel access, and protect cover structures during normal operation and upset conditions.

Conservation vents and emergency vents set the pressure and vacuum thresholds that protect membrane and rigid covers from structural overload. Flame arresters, in plate element, end-of-line, and inline deflagration configurations, interrupt flame propagation at cover openings and connected piping. Safety selector valves route or isolate gas flow paths. Manway covers, gauge hatches, and viewport covers provide gas-tight access for maintenance without releasing biogas to atmosphere.

The MCG 2000MAX level transmitter provides continuous cover position monitoring, while the MCG 5200 wireless system relays pressure, alarm, and position data to remote displays without new cabling through the cover structure. All devices are built for wet, corrosive, and sulfide-containing biogas environments with metallic construction and biogas-compatible seals. The Expanda-Seal™ design on manway covers minimizes fugitive emissions at the cover interface.

Cover Protection vs. Safety vs. Access Devices

Biogas cover equipment is organized by device role rather than a single product family, because each digester cover requires multiple coordinated functions working in parallel. Cover protection devices manage normal operating conditions and provide continuous measurement. Safety and isolation devices enable controlled gas routing and remote alarm notification. Cover access and inspection devices provide physical access and last-resort overpressure protection. Flame protection devices provide flame front interruption at every opening in the cover gas space. All device types are selected and specified together as a coordinated cover-level solution, because a gap in any function creates an unacceptable risk in continuous biogas service.

When to Specify Biogas Cover Equipment

Biogas cover equipment is specified when a digester or gas holder cover requires integrated protection, access, and monitoring as a complete engineered system:

Municipal Wastewater Treatment Plants Anaerobic digesters processing primary and secondary sludge, where digester cover integrity is a continuous safety requirement and pressure excursions must be managed within defined setpoints.
Industrial and Agricultural Biogas Facilities On-farm, food processing, and industrial anaerobic digesters operating under low-pressure biogas service, where cover protection and flame prevention must meet local safety codes.
Biogas Storage and Gas Holder Applications Membrane or rigid gas holder roofs requiring coordinated pressure management and cover position monitoring to protect storage structures during filling, drawdown, and upset conditions.
Covers Requiring Safe Maintenance Access Any digester cover where routine inspection and maintenance must be performed without releasing biogas to atmosphere, requiring gas-tight manway and gauge hatch designs.
Facilities with Remote Monitoring Requirements Operations where real-time alarm notification and pressure data must reach a control room or mobile device without new instrumentation cabling through the cover structure.

Why Shand & Jurs Biogas Cover Equipment Excels

Digester Covers Requiring Coordinated Multi-Device Protection

A single cover may require conservation vents, flame arresters, emergency vents, manways, and monitoring in a coordinated package. Shand & Jurs provides the complete device set from one source, simplifying specification, procurement, and installation.

Continuous Biogas and Digester Gas Service

All devices are engineered for wet, corrosive, and sulfide-containing gas environments that degrade standard hardware. Metallic construction and biogas-compatible sealing materials are standard, not optional.

Facilities Requiring Maintenance Without System Shutdown

Gas-tight manway covers, including the Expanda-Seal™ design, allow personnel access and inspection without venting the cover gas space to atmosphere, protecting both emissions performance and operator safety.

Remote and Wireless Alarm Notification

The MCG 5200 wireless monitoring and alarm system and WirelessHART adapter eliminate the need for new cable runs to cover-mounted instruments, reducing installation cost and complexity on existing and new digester structures.

Applications Requiring Both Mechanical Protection and Continuous Level Data

The MCG 2000MAX level transmitter integrates cover or liquid level measurement alongside mechanical protection devices, providing a single cover-level data stream for SCADA and control system integration.

Flame Protection at Multiple Cover Openings

Three flame arrester configurations, plate element at cover openings, end-of-line for external sources, and inline deflagration for connected piping, address every ignition pathway at a single digester cover.