Anaerobic Digestion - Biogas Storage DuoSphere™ Double Membrane Gas Holder

DuoSphere Double Membrane Gas Holder

Anaerobic Digestion – Biogas Storage
DuoSphere™ Dual Membrane Gasholder

As energy costs grow, facilities are increasingly seeking alternative fuel sources, including biogas, to help offset power costs for their plants. WesTech has many years of experience in supplying customers with anaerobic digestion equipment that adds value to plant operations.

By storing methane contained in the biogas, the DuoSphere allows a steady fuel source for a variety of functions.

  • Process heating
  • Sludge drying
  • Cogeneration
  • Facility heating
  • Vehicles and equipment

The DuoSphere offers innovative designs for digester gas storage and alternatives for conventional digester covers. DuoSphere gasholder structures are strong, lightweight, and versatile – a preferable choice in biogas storage for your municipal or industrial applications.

Whether your application requires a slab-mounted gasholder or a tank-mounted alternative to steel digester covers, our DuoSphere dual membrane structures are standout solutions for biogas storage. The superior design features high-strength fabric and utilizes a radio frequency welding process for increased strength and safety.

Slab-Mounted DuoSphere Gasholders – A Simple and Inexpensive Way to Add Gas Storage

  • Mounts to flat concrete slab or short walls
  • Gas chamber comes sealed from the factory
  • Easy access to inspect inner membrane

Tank-Mounted DuoSphere Digester Cover – An Innovative and Cost-Effective Solution for New and Replacement Covers

  • Alternative to more costly steel covers
  • Ideal for retrofits
  • Variable liquid level

DuoSphere Biogas Storage Diagram

Expert Installation

Make sure your dual membrane installation goes as quickly and smoothly as possible. Membrane structures are less costly and quicker to install than steel structures, in general. By choosing WesTech for your installation, you’ll cut down the installation time even further. Our many years of experience makes the installation experience seamless and efficient for our customers.


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  • Critical inner gas holding membrane is independent of the outer membrane
  • PVC-coated polyester fabric membranes, stainless steel anchors
  • Access is available to inspect the inner membrane at all times
  • Airflow between the membranes is accurately controlled
  • Gas detection equipment monitors the air between the membranes
  • AMCA spark-resistant and explosion-proof pressurization fans
  • Complete service from design to fabrication to installation and commissioning
  • Fast installation (1 to 3 weeks)
  • Gasholder volumes from 700 ft.3 to 317,800 ft.3 (20m3 to 9000m3)
  • Radio frequency welds form a very strong seam
  • Volume is measured ultrasonically


  • Constant pressure regulation
  • Custom flow and sizes
  • Low capital and installation cost
  • Absolute odor containment
  • No field welding, painting, or blasting
  • Often eliminates the need for complex reinforcing cables or frameworks
  • When used for retrofits, allows reuse of existing mechanical equipment