Algas-SDI Gas-Air mixers are designed and manufactured for industrial and utility applications using the highest quality materials and components. Decades of experience and a focus on continuous improvement have led to the most reliable and durable mixers available today. World-wide applications include propane-air or LPG-air mixing for natural gas replacement, coal gas and coke oven gas replacement, and digester gas augmentation or replacement. Standard packages are set up for natural gas replacement using propane or LPG. Other gas mixtures can be accommodated with configuration options. Most models are available in compliance with European directives -- PED and ATEX marked where required. All standard models are FM approved.


Algas-SDI VAPORAIRE mixers use propane or LPG to create a synthetic natural gas mixture by entraining air and gas through a venturi and diffuser set. These systems are designed for the rigors of heavy duty industrial applications and outdoor installation. Systems 21MM Btu/Hr and larger are equipped with a temperature controlled enclosure and PLC based controls. All units are manufactured with ASME "U" stamped surge tanks and have CRN's for all Canadian provinces. Discharge pressures from 5-15 PSIG with propane and 5-8 PSIG with LPG are available using atmospheric air while discharge pressures up to 40 SPIG are available with compressed air. Models requiring compressed air are supplied without surge tank.

PLC controlled mixing unit provides 100% turndown capability and mixed gas pressures up to 15 PSIG for commercial propane LPG feedstock (8 PSIG for butane rich LPG mixtures) Up to 40 PSIG is available with compressed air.

  • Explosion-Proof design -- Class I, Div 1, Gr. D -- can be placed close to storage tank and vaporizer
  • 110V/50-60Hz or 220V/50-60Hz available
  • Heated explosion-proof enclosure
  • FM Approved
  • Capacities
    • 7 - 250 MMBTU/hr
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Algas-SDI BLENDAIRE mixers accurately mix 2 gas streams at pressures up to 150 PSIG for standard units and up to 250 PSIG for high pressure units. Standard packages are set up for LPG-air mixing to replace or augment the supply of natural gas for industrial back-up or for city gas (synthetic natural gas) production as a lead in to natural gas or for augmenting the supply of natural gas such as peak shaving. At the heart of the BLENDAIRE is the FVO 3-port mixing valve that automatically and accurately balances the orifice area for each flow stream according to flow rate. The process does not rely on feedback from electronic controls that can fail or go out of calibration. Operation of these units is simple and failsafe, relying on cross linked regulators to equally govern the pressure entering each side of the mixing valve. Valve port position and flow rate position indicators are provided for direct visual indication.

This proportional mixer provides accurate LPG/Air mixtures within desired adjustable ratios and delivery pressures of up to 150 PSIG.

  • High turn-down capability does not rely on flow meters for mixing accuracy
  • Wide mixing ratio capability -- 100% port-to-port
  • Explosion-Proof design -- Class I, Div. 1, Gr. D
  • PLC based controls with temperature and pressure transmitters
  • Large 6" dial differential pressure indicator for direct read-out of regulated pressures
  • Port Ratio indicator and Flow Rate indicator
  • Optional Automatic ratio adjustment system with explosion proof servo motor and PID control enhances mixing ratio accuracy based on feedback from calorimeter or gas analyzer refines
  • Optional touch screen operator interface available standard in four languages -- English, French, Spanish and Turkish
  • 110V/50-60Hz or 220V/50-60Hz
  • FM approved
  • European PED and ATEX compliant units available
  • Capacities
    • 16 - 870 MMBTU/hr

Natural Gas Air Mixing System

  • Complete natuaral gas/air mixing system includes Consta Mix mixing valve, Eclipse blower and zero governor.
  • Available up to 5 PSIG delivery pressure.
  • Capacities range from 560,000 BTU/Hr - 7,850,000 BTU/Hr.
  • 100 to 1 turndown (with cooling loop).
  • Perfect mixer for burner pre-mix applications or digester gas replacement for generating electricity at wastewater treatment plants.
  • Special epoxy coated systems also available for mixing digester gas with natural gas.
Natural Gas Air Mixing Systemproduct brochure product flyer application report
ISO9000 Certified