Anaerobic digestion
Anaerobic digestion is a process through which micro-organisms break down organic matter, such as animal manure, wastewater biosolids, and food wastes, in the absence of oxygen. Anaerobic digestion intended for biogas production takes place in a sealed tank (called an anaerobic digester), which is designed and constructed in various shapes and sizes specific to the site and feedstock conditions. These sealed vessels contain complex microbial communities that break down the waste and produce biogas and digestate (i.e., the solid and liquid material end-products of the process).
Feedstock
Process and technologies
Process
Usually, the produced biogas must be dried and drained for condense water and biological or chemical cleaned for H2S, NH3 and trace elements. Further upgrading of the biogas to increase the CH4 content could be realized by membrane separation of CO2 and pressurising the biogas.
Product
Anaerobic digestion produces two valuable outputs, namely biogas and digestate. Biogas is composed of methane (CH4), which is the primary component of natural gas, at a relatively high percentage (50 to 75%), carbon dioxide (CO2), hydrogen sulfide (H2S), water vapor, and trace amounts of other gases. The energy in biogas can be used like natural gas to provide heat, generate electricity, and power cooling systems. Biogas can also be purified by removing the inert or low-value constituents (CO2, water, H2S, etc.) to generate renewable natural gas (RNG). This can be sold and injected into the natural gas distribution system, compressed and used as vehicle fuel, or processed further to generate alternative transportation fuel or other advanced biochemicals and bioproducts.
The digestate can be used in many beneficial applications provided that is is appropriately treated post processing. This could be in form of animal bedding, nutreint-rich fertilizer, organic-rich compost, or as soil amendment.
Technology providers
CCS
CCS Enegie-advies together with Greenmac developed the Bio-UP technology which is able to upgrade the produced biogas into green gas. CCS offers the Bio-UP technology via lease contracts or turn-key. The Bio-UP is a proven concept which already operates at "melkveeproefbedrijf De Marke".
Biogas Plus
| General information | |||
| Company: | Biogas Plus | Webpage: | https://www.biogasplus.nl |
| Location: | Venray (NL) | Business-Model: | |
| TRL: | 9 | Patent: | |
| Technology name: | Compact Plus | Technology category: | |
| Technology and process details | |||
| Reactor: | Isolated concrete tank with double-membrane isolated roof. Two agitators | Heating: | |
| Atmosphere: | Pressure: | bar | |
| Capacity: | 18.000 tons (input), 320.000 Nm3 green gas/year (output). | Temperature: | °C |
| Catalyst: | Other: | ||
| Feedstock and product details | |||
| Feedstock: | Animal manure | Product: | Green gas |
| Pre-treatments: | Post-treatments: | Biogas upgrading (integrated) | |