Tecnología desarrollada para el proceso de compostaje

At METROCOMPOST we develop proprietary technology, the COMPOTÚNEL. This composting system, patented by METROCOMPOST, is characterised in that it accelerates the composting process, guaranteeing exhaustive control over the biomass to be composted at all times and thereby completely avoiding the emission of gases or liquids that could be environmentally hazardous.

It is a hermetic parallelepiped enclosure built of concrete, cast on site or prefabricated, the entrance of which has an insulating door with a watertight seal wherethrough the material is loaded and unloaded. Its size varies between 3-8 m in width and height and between 10-40 m in length. The process parameters are controlled by means of probes that provide constant information about the parameters, such as:

  • Temperature of inflowing gases
  • Temperature of outflowing gases
  • Temperature of the mass
  • Level of 02, CO2 and NH3 in both mass and gases

These measurements are transmitted to a programmable automaton, which in turn sends all the data to a programmed PC that activates the process constraint variation systems. In our technology, ventilation is carried out through a false perforated floor by depression (aspiration) and, in many cases, there is a possibility of recirculating the process air. The matrix is usually introduced very wet, optionally using for said wetting action both the accumulated leachates and any other supply source, in such a manner as to prevent liquids from flowing out of the process towards the exterior, thus ensuring a closed process.

The gases collected in the tunnel and which we do not want to reuse are impelled towards purifying biofilters and subsequently emitted into the atmosphere under optimum conditions. Gas conditioning systems or pre-wash systems can be used to ensure the proper functioning of the biofilter.


los puntos fuertes de los Compotunel©

  • High-resistance, doubly reinforced prefabricated concrete structure.
  • Modular volume and arrangement of the COMPOTÚNELs and biofilters.
  • Special, low-maintenance perforated floor which allows fast filling and emptying.
  • Aspiration or impulsion plenum free of leaks or load losses.
  • Bay gas intake.
  • Recirculation of gases which allows variation in the conditions (temperature and humidity) of tunnel inflow gas.
  • Recessed loading bay to prevent bad smells from emanating outwards.
  • Highly effective biofilters, with a proprietary design and extensively tested.
  • Short gas circuit to avoid load losses and other problems.
  • High-performance, highly flexible fans to operate with a broad range of materials and protected against corrosion.
  • Temperature and gas control with a minimum of three temperature sensors and three gas-capturing probes in the material mass.
  • Temperature measurement in the biofilter for controlling its biological activity level.
  • Measurement of temperature, oxygen, carbon dioxide and ammonia in the gases in order to control the progress of the process.
  • Ambient temperature and humidity reference for monitoring the control programme.
  • Regulation of humidity by means of an automated irrigation system.
  • Collection and re-incorporation of all the leachates to the process when it reaches thermophilic or hygenisation temperatures.
  • Purification of the leachates in accordance with the material to be treated, management model and plant operation.
  • Ventilation in accordance with temperature and oxygen to avoid anaerobiosis.
  • Highly reliable and easily extendable robust, compact and modular automaton (PLC).
  • Online digital and graphic computer display of all process variables.
  • Accumulation of quality and production batch histories.