ENERGY
Dual stage system image
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Dual stage: unique technology

The “double-stage” technology or system was developed exclusively by our partner SnowLeopard after exhaustive studies of the different processes of anaerobic digestion within the 6th Framework Program of the European Union. It represented a great qualitative leap in the production of this renewable gas, as recognized by important innovation awards in Germany, a reference country in the biogas sector. This technology not only optimizes the anaerobic digestion process, but also gives its plants great flexibility in using the different substrates available. This results in smaller plants with better yields. Its efficiency and reliability has been proven by more than 20 years of experience and more than 50 plants in operation in Europe, South America, Asia and Africa.

DUAL STAGE SYSTEMS

Dual stage systems

Separation of the anaerobic digestion process into two “phases” or “stages”. Learn more about anaerobic digestion.

Biogas Origin

Single-stage plants

They have one or more digesters in which all the phases of the biogas production process take place:.

  • Hydrolytic
  • Acidogenic
  • Acetogenic
  • Methanogenic

Dual stage systems

They include two hydrolysis tanks in addition to the digesters. Separating and optimizing the anaerobic digestion phases:

  • Hydrolysis tanks: hydrolysis and acidogenesis.
  • Digesters: acetogenesis and methanogenesis.
Comparison of single-stage and two-stage system

SINGLE-STAGE STORAGE SYSTEM:

Feeding tank

Feeding tank

Digester

Digester

Storage tank

Storage tank

TWO-STAGE SYSTEM:

Feeding tank

Feeding tank

Hydrolysis Tank I and II

Hydrolysis Tank I and II

Digester

Digester

Storage Warehouse

Storage Warehouse

DOUBLE STAGE

Proven advantages of the dual stage

They have their scientific-biological explanation in that:

  • The different microorganisms involved in the anaerobic digestion process require specific conditions and ecosystems (pH, temperature, nutrients…etc.) and
  • With the separation of stages, environments adapted to them are created, thus enhancing their characteristics.
Benefits of the double cover

These microorganisms include:

  • Hydrolytic bacteria: resistant and tolerant to oscillations in the environment and type of substrate.
  • Methanogenic bacteria: very sensitive to any disturbance.
Microorganisms section
THIS EMPIRICAL EVIDENCE GENERATES IMPORTANT BENEFITS:

Esta evidencia empírica genera importantes beneficios:

Menor CAPEX y espacio en tanques

  • Tanques más reducidos
  • Reducción y eliminación de sistemas no necesarios:
    • Post digestor
    • Compostaje del sólido
  • Posibilidad de instalación en parcelas reducidas (< 2,5Ha)

Mayor rendimiento y menor OPEX

  • Capacidad de producción de biometano, en función del sustrato, de hasta un 35% superior.
  • Menores costes de mantenimiento gracias al empleo de equipos de alta calidad.
  • Higienización en el propio digestor gracias a las condiciones del proceso de doble etapa.

Ambientales

  • Ausencia de olores
  • Menores emisiones de CO2

Flexibilidad

  • Flexibilidad en el cambio de sustratos y en el nivel de producción (incluso diaria) gracias a:
    • La mayor frecuencia de alimentación del tanque
    • Los menores tiempos de retención
  • Con la acidificación biológica, mayor capacidad para tratar un amplio número de sustratos:
    • Muy energéticos
    • Fibrosos

Calidad

  • El ahorro en gastos superfluos (ej. menor tamaño de los tanques) se destina a equipar la planta con equipos de alta calidad.
  • Proveedores con cientos de referencias en depósitos, gasómetros, bombas y agitadores.
  • Laboratorio propio para determinar el potencial metanogénico, la selección del inóculo y el diseño de la dieta.