Microwave Pyrolysis Plant mf200B – Single Unit
The mf200B is a continuous microwave pyrolysis plant converting wood pellets into biochar and fractionated condensates (bio-oil / aromatics / acid / water fractions). The design is engineered for process stability, reproducible product quality, and operational safety: inertized solids handling, controlled pressure/vacuum operation, staged condensation, defined liquid-phase separation, and controlled utilization of non-condensable gases (NCG) via a low-NOx burner.
At a glance
Feedstock
- Wood pellets (moisture typically accounted for in the feed)
- Optional additives in small ratios (e.g., zeolite/starch depending on target operation and products)
Main products
- Biochar (solid product, typically filled into big-bags)
- Fractionated condensates (e.g., heavy phenolic fractions, phenol/cresols, BTX / light-oil cuts)
- Acid / water fractions (e.g., acetic-acid / methanol containing, process water)
- NCG (non-condensable gases) for controlled energy utilization
Typical operating ranges
- Reactor temperature: 275–450 °C (common operating point e.g. around 330 °C)
- Microwaves: 2.45 GHz, typically 200 kW average / 300 kW pulse
- Design throughput (single unit): 1,000 kg/h biomass (reference per line)
Process chain in 10 steps
- Reception, storage, conveying
Wood pellets are stored in silos/containers and fed to the process line via enclosed conveying equipment. A dedicated de-dusting stage reduces fines. - Preheating & conditioning (input silo)
The material is conditioned in a heated buffer silo, typically to 60–65 °C, supporting stable feeding and reproducible reaction conditions. - Inertization & gas-tight feeding
Critical sections are operated with an N₂ blanket. Feeding uses screws/feeders and isolation elements to minimize air ingress into the hot/inert process area. - Microwave reactor (core conversion)
Biomass is pyrolyzed in a rotary reactor within the selected temperature window. Temperature, residence time, and pressure level are controllable and determine product distribution and quality. Microwaves deliver energy directly into the material (2.45 GHz). - Biochar discharge – gas-tight and safe
Biochar discharge is vacuum-/gas-tight and uses an N₂ barrier. A cooled discharge section reduces temperature and glowing/ignition risk. - Biochar cooling, monitoring, packaging
Biochar is conveyed via cooled screws. Hot-spot / glowing particle detection and a defined intervention logic (e.g., water injection) increase operational safety. Packaging typically via big-bags. - Hot gas de-dusting (cyclone stage)
The reactor vapor/gas stream is relieved of particulates via cyclone(s), protecting the condensation train and downstream equipment from fouling. - Fractionated condensation (quench + condenser cascade)
A staged cooling concept condenses product classes within defined temperature windows (heavy fractions → mid fractions → light oils / acid/water fractions). This enables better separation than a single mixed condensate. - Aerosol removal (WESP)
A wet electrostatic precipitator (WESP) removes remaining aerosols and fine droplets from the gas stream, stabilizing product quality and gas handling. - Vacuum / gas handling & NCG energy utilization
A liquid-ring vacuum system stabilizes pressure operation and conditions the gas stream (condensation/drying/coalescing). Non-condensable gases are routed to a low-NOx gas burner for controlled energy utilization.
Component overview (single unit)
| Module group | Typical components | Function / benefit |
|---|---|---|
| Feedstock handling | Storage/silos, conveyors, dosing screws, de-dusting | Stable mass flow, reduced dust load |
| Preheating & inertization | Heated input silo, N₂ blanket, pressure/vacuum interface | Reproducible conditions, oxygen exclusion |
| Feeding & dosing | Gas-tight feeder/lock section, isolation elements | Minimized air ingress, stable feeding |
| Reactor module | Microwave rotary reactor, waveguides, temperature/pressure instrumentation | Core conversion: biomass → vapors/gas + biochar |
| Biochar handling | Gas-tight discharge, N₂ barrier, cooling, hot-spot detection, screening/de-dusting, big-bag filling | Safe solids chain, defined product quality |
| Hot gas de-dusting | Cyclone(s), optional fine separation stage | Protects condensation, reduces fouling/maintenance |
| Condensation | Quench + multi-stage condensers, temperature stabilization, product drains | Fractionated condensates instead of a mixed product |
| Aerosol cleaning | WESP with media handling | Removal of fine droplets/aerosols |
| Liquid-phase separation | Decanter(s), coalescer/boot, tank farm (partly heated), N₂ blanket | Phase separation, storage-ready products |
| Acid / water | Acid recovery (e.g., acetic acid concentrate), neutralization (NaOH), pH control | Utilization of side streams, controlled water pathway |
| Vacuum & gas conditioning | Liquid-ring vacuum, gas condenser/dryer/coalescer, control valves | Process stability, protection of downstream systems |
| Energy utilization | Low-NOx gas burner, flame arrestor/backflash protection, pressure control | Safe utilization of NCG energy potential |
| Utilities | Thermal oil, cooling water (redundant pumps), N₂ system (generator + backup), compressed air | Availability and stable media supply |
| Automation / analytics | DCS, online gas analytics (O₂/CO/CO₂/CxHx/N₂), optional GC-MS | Quality assurance, traceability, optimization |
Safety by design
The mf200B applies a multi-layer protection philosophy across process operation, mechanical design, and automation logic. The objective is robust, controllable behavior even under deviations (e.g., feed variability, condensation load changes, pressure fluctuations).
- Inertization (N₂): Minimizes oxygen ingress in hot sections (reactor, discharge, tanks).
- Gas-tight solids handling: Locks/feeders separate ambient conditions from process atmosphere.
- Biochar safety chain: Cooling, hot-spot/glowing detection, and defined intervention logic.
- Pressure/vacuum operation: Controlled flow direction and stable process conditions.
- NCG handling: Control valves and flame arrestors for safe energy utilization.
Instrumentation, control & analytics
For reproducible product quality and safe operating modes, the plant is designed for continuous monitoring and closed-loop control. A central automation system coordinates feed, reactor, condensation, separation, and utilities. Online gas analytics (e.g., O₂/CO/CO₂/CxHx/N₂) supports monitoring, quality tracking, and safety interlocks.
Operational transparency
- Trend and event recording (setpoints, alarms, states)
- Product/operating condition traceability for audits and reporting
Typical control loops
- Temperature control (reactor and condenser stages)
- Pressure/vacuum control
- Media supply control (thermal oil, cooling water, N₂, compressed air)
Products & interfaces
- Biochar: Big-bag packaging; screening/de-dusting can be integrated.
- Condensates: fractionated streams routed to dedicated tanks; organic and aqueous phases separated.
- Acid / water pathway: optional acid concentrate; water pathway with neutralization and pH control.
- NCG: utilized via low-NOx burner; heat integration depends on project layout.
Technical data (short format)
| Design throughput | 1,000 kg/h wood pellets (reference) |
|---|---|
| Reactor temperature range | 275–450 °C (common operating point e.g. 330 °C) |
| Microwaves | 2.45 GHz, typically 200 kW average / 300 kW pulse |
| Condensation | Quench + multi-stage condenser cascade + WESP |
| Separation | Decanter/coalescer; tank farm (partly heated, N₂ blanket) |
| Gas handling | Liquid-ring vacuum + gas conditioning; low-NOx burner for NCG |
FAQ
Which biomass types can be processed?
The primary design feed is wood pellets. Other pelletized biomasses are generally feasible, but require alignment of moisture, ash content, bulk density, as well as adaptation of temperature profile and condensation strategy.
Why fractionated condensation instead of a “mixed oil”?
Different compound classes condense in different temperature windows. Staged condensation improves separability, storage stability, and downstream marketing options compared to a single mixed condensate.
How is biochar handled safely?
Through a gas-tight discharge with an N₂ barrier, controlled cooling, and hot-spot/glowing detection with a defined intervention logic. This reduces the risk of air ingress and smoldering in the solids pathway.
What happens to non-condensable gases (NCG)?
The gas stream is conditioned and routed to a low-NOx burner for controlled utilization. Pressure control and flame arrestors support robust, safe operation.
How is product quality ensured?
By stable operating modes (DCS), online analytics, reproducible temperature/pressure control, and defined separation (decanter/coalescer, tank concept). This enables traceable documentation of settings and product batches.
Contact / Next steps
For project-specific engineering (feedstock data, target products, utilities concept, layout), we can provide a technical short description, an interface list, and a project-specific mass/energy balance package upon request.
Optional documents: factsheet (PDF), single-unit layout, utility specification, safety/interlock overview.