TO PRODUCE BIOMETHANE, USE WATER_

There is a large enough difference in water solubility between the CO₂ and CH₄ molecules to allow their separation by absorption under specific pressure, temperature and flow conditions. Only water is used. To reduce consumption, it is regenerated and used in a closed loop. The separation medium is water, which is free and independent of any supplier of separation media, such as membranes, adsorbents or amine solutions.

Biomethane plants that process waste gas must work within a range, not at a single point, because the biogas produced varies in flow and composition. Every separation process entails losses of the target gas, but to control them a flash distillation is carried out, which recovers the CH₄ absorbed in the water.

Absorption and desorption processes are markedly non-linear, which is why AGF's operation is essential to ensure the production of a valid gas within the design range. In turn, for the plant to run most of the time, a preventive maintenance plan and a supply of critical spare parts are also needed. The plant's main consumable is water, in quantities below 1 m³ a day. The main operating cost is electricity consumption.

The stability and automation of the plant require a complex control engineering design that allows it to run autonomously. Integration reaches its optimal application when the biogas plant communicates with the biomethane plant, which adapts to process whatever gas the biogas plant is producing. The biogas plant, in turn, produces biogas depending on conditions. The result is that the biogas plant can work at a constant dome pressure.