DRANCO process

The DRANCO (DRy ANaerobic COmposting) process is an advanced biotechnological process for an environmentally friendly and cost-effective treatment of organics derived from municipal solid waste. With its long experience and its extended reference list, the DRANCO process is a well-known and reliable anaerobic digestion technology. The DRANCO technology is marketed throughout the world by DRANCO nv or by means of its exclusive license partners.

Technology

The patented DRANCO process is an unique process because of the vertical design, high-solids concentration and the absence of mixing inside the digester.  These three principles combined with more than 30 years of experience, make the DRANCO process the most efficient way to digest solid and semisolid feedstocks.

Due to its origin, the DRANCO digestion technology has often been applied for the treatment of mixed or residual household waste, which were commonly landfilled. These plants operate at a dry matter content in the digester of up to 40 %. However, DRANCO is a widely applicable technology that can treat different kinds of waste streams.  In other DRANCO plants, source separated organics and yard / food waste is being treated at a dry matter content of 20 to 35%.

The biogas can be used for the production of electricity and/or heat or, after upgrading, as biomethane.

DRANCO process characteristics

• vertical fermenter: feeding at the top and extraction through a conical outlet at the bottom
• single-phase digestion with intensive recycling of the digestate
• thermophilic or mesophilic operation
• compact, well-insulated digesters with minimal heating requirements
• high-rate dry digestion (very high loading rates and biogas productivities can be achieved)

Advantages

The DRANCO process has some significant advantages compared to other conventional digestion technologies:

• “dry” anaerobic digestion
  • high solids digestion
  • high loading rate and biogas productivity
  • small digester volumes
  • crust formation or sedimentation is avoided
• vertical digester with conical outlet
  • extraction at the lowest point
  • no accumulation in the digester
  • minimal surface requirement
• one-phase digestion
  • reduced complexity
• no mixing, stirring or gas injection in the digester
  • no maintenance or failures inside the digester
• intensive recirculation
  • well controlled external inoculation
  • optimum mixing of fresh feedstock with digestate
• thermophilic temperature (48-55°C) possible with a minimum of heat
  • higher biogas yield
  • more efficient process
  • kill-off of pathogens and seeds
• automated process control
  • high operational safety
• robust and industrial system
  • high reliability
• single digesters with a capacity of up to 60.000 tons per year of household waste organics

DRANCO: the best way to digest household waste organics!