Biochar & Microwave Technology – µSoil, µFuel & More
µSoil and µSoil+: Organic Biofertilisers from the NRU Two-Stage Process
Two product routes – one two-stage process
µSoil and µSoil+ are produced by the same two-stage process: anaerobic digestion under the NRU protocol with Bionic µChar (Stage 1) followed by controlled aerobic composting (Stage 2). The difference lies in the intensity of nitrogen enrichment and co-substrate composition.
| Property | µSoil Standard | µSoil+ |
|---|---|---|
| Nitrogen content | Defined NPK specification; CE-eligible under EU FPR PFC 1 | Higher nutrient value; full NRU system with stronger nitrogen binding |
| Carbon matrix | Controlled µChar fraction; high Humus-C content | Same µChar base; higher overall nutrient value |
| Nitrogen form | Char-adsorbed and humus-complexed; controlled slow-release | Enhanced slow-release profile through full NRU system |
| Regulatory pathway | CE-eligible in principle under EU FPR CMC 14 (revision pending) + PFC 1 | CE-eligible in principle under EU FPR CMC 14 (revision pending) + PFC 1(C)(II) (slow-release fertiliser) |
Stage 1: NRU Protocol – Nitrogen Retention in Digestion
Bionic µChar is added to the biogas reactor. The high adsorption capacity of µChar (documented in BLG GmbH process analytics) produces three simultaneous effects: ammonium nitrogen is directly adsorbed onto the surface and carried through the process as a slow-release carrier; pH buffering keeps the NH₄⁺/NH₃ equilibrium in the non-inhibitory range and retains the large majority of total nitrogen through the digestion stage; and methane yield is increased in parallel.
The digestate leaving Stage 1 is not a fertiliser for direct field application. It is a concentrated, hygienised intermediate with a known nitrogen content — the optimal feedstock for Stage 2.
Stage 2: µSoil Composting – Nitrogen Concentration in the Solid Product
The nitrogen-loaded digestate is combined with co-substrates and a fresh µChar top-up, adjusted to a C:N ratio optimal for thermophilic composting, and composted aerobically. The cation exchange capacity of µChar prevents ammonia volatilisation during the hot composting phase and accelerates humification. Nitrogen retention through the two-stage process substantially exceeds conventional digestate or composting routes according to NRU White Paper v11 and BLG GmbH process modelling (literature comparison; project-specific field validation pending).
µSoil Product Properties
| Property | Description |
|---|---|
| Physical form | Solid; baggable or bulk delivery — no liquid logistics |
| NPK specification | Defined N, P and K contents; CE-eligible under EU FPR PFC 1 |
| µChar content | Controlled fraction; CE-eligible in principle under CMC 14 (EU FPR 2019/1009, revision pending) |
| Nitrogen form | Char-adsorbed and humus-complexed; controlled slow-release |
| Hygienisation | PFPR-compliant through the AD stage (≥55°C, ≥10 days); EU FPR pathogen standard met at Stage 1 |
| Stable carbon | High fixed carbon content in µChar; certifiable long-term carbon storage |
| Carbon balance | Net carbon-negative; CRCF crediting pathway applicable |
Agricultural Benefits
- Slow-release nitrogen: demand-driven release through root exudates and microbial activity — no uncontrolled ammonia loss on application
- Higher nitrogen use efficiency compared to liquid digestate application, which loses a substantial fraction of nitrogen through volatilisation
- No liquid logistics: solid, storable, transportable and applicable year-round
- Stable soil carbon: high fixed carbon content in µChar; contribution to long-term humus formation and CO₂ sequestration
- CE-marking under EU FPR: single conformity pathway for the entire EU market
- Pathogen-free: hygienisation standard met through the AD stage at Stage 1
Further Technical Documentation
The complete technical and scientific basis of the NRU–µSoil process — including process parameters, nitrogen balances, comparison with conventional digestate routes, economic model and regulatory roadmap — is documented in the NRU–µSoil Policy White Paper. The document is available in the Downloads section.
Bionic Technologies
Bionic has been developing and operating microwave conversion facilities for industrial use for many years. The central question is how biogenic residues, waste, and difficult material streams can be converted into usable energy, high-quality products, and stable CO2 sinks. The following technologies form a modular building block system from which the appropriate solution is configured for each project.
µFuel – micro-fuel
Bionic µFuel is the core technology of the Bionic platform. In a specially developed microwave reactor, organic materials – for example, wood, agricultural residues, or biogenic waste – are thermally converted in a low-oxygen environment.
µSoil – micro-soil
Bionic µSoil begins exactly where μFuel ends: with the use of the biochar generated in the process.
µWaste – micro-waste
µWaste describes the application of the μFuel technology to plastic and municipal waste streams.
µTyre – micro-tyre
µTyre is the Bionic technology tailored specifically for scrap tires and rubber-containing residues.
µPower – micro-power
Under µPower, Bionic summarizes the coupling of microwave conversion with classic power plant and CHP technology.
µSorb – micro-sorb
µSorb denotes the Bionic product line for filter and adsorbent materials based on biochar.
AI-supported Process Control
With the increasing complexity of the facilities, the digital level gains importance. Bionic therefore relies on AI-supported process control.
µCTL – micro-char-to-liquid
µCTL forms the conclusion of the technological chain: the refinement of biochar into synthetic liquid fuels.