DOI: 10.5281/zenodo.17815098
title: Functional sample - Microwave unit for controlled pyrolysis of biomass and waste materials equipped with a switching microwave source for precise temperature control in the reactor

description: Dataset description:

Original CSV, PDF and TIF data from original research within the project INOVO!!! and supported by the ENREGAT project. Precisely, there are 12 number of Figures, 10 number of schematics of devices, 1 PDF and 6 Datasets:

PDF:
funkcni_vzorek - complete text of the functional sample.
evidencni_formular - confirmation of receipt of functional sample 

The result is a functional microwave unit with a pulsed microwave source, temperature control and regulation, designed for direct pyrolysis of biomass and waste materials in a controlled microwave field. The microwave unit operates with precise temperature control in the reactor using a pulsed microwave source and online thermocouples, ensuring a stable pyrolysis process at a constant temperature and thus good reproducibility of results (i.e., mass balance of pyrolysis products, physical and chemical properties of pyrolysis products – e.g., charcoal).
During pyrolysis, thermochemical decomposition of materials (e.g., organic, polymeric, etc.) occurs through convection at high temperatures (500-800°C) without oxygen access (i.e., in an inert atmosphere), with the simultaneous formation of technologically and energetically usable pyrolysis products, i.e., pyrolysis gas, liquid condensate (pyrolysis oil), and solid porous carbonaceous residue (charcoal). The pyrolysis products obtained have various applications, e.g., the solid carbonaceous residue (charcoal) can be used as a sorbent, catalyst carrier, active ingredient for water treatment, gas purification, the cosmetics or chemical industry, soil remediation, while pyrolysis gas and liquid condensate can be used for energy or chemical processing.
The microwave unit enables unique thermochemical decomposition and valorization of biological and other waste materials in an inert atmosphere into pyrolysis products, where a magnetron (microwave source) in switching mode generates microwave radiation conducted through a waveguide.

This functional sample is intended for direct use by a research organization for further activities, in particular for research and development, teaching, internal testing, demonstration purposes, and implementation within the scope of its scientific, educational, or operational activities.

Obrazek_1 - Schematic diagram of microwave equipment for pyrolysis of biomass and waste
Obrazek_2 - Connection/interconnection of individual system
Obrazek_3 - The LOXONE (a) and FileZilla (b) software environments.
Obrazek_4 - Thermocouple with Faraday cage-based enclosure schematic representation (a) and real application without biomass (b)
Obrazek_5 - Precise placement of the thermocouple with Faraday cage-based shielding outside the direct collision path of microwave radiation
Obrazek_6 - Magnetron safety shutdown: gentle shutdown using LOXONE software (a), gentle shutdown using a power controller (b), and rapid (non-gentle) magnetron shutdown (c)
Obrazek_7 - Safety measures after switching off the magnetron (a), detail of individual controls (b)
Obrazek_8 - Stability of SiC microwave heating at different powers for temperatures of 500°C (a), 600°C (b), and 700°C (c) 
Obrazek_9 - Reactor before (a) and after (b) pyrolysis, where the thermocouple is fitted with textile fabric and forms a Faraday cage. Biomass RMS + 10 wt% biochar from RMS (a)
Obrazek_10 - Stability of microwave heating of biomass at parameters of 500 °C/600 W; 600 °C/700 W and 700 °C/800 W for corn biomass (CC-RED) (a) and red mombin (RMS) (b)
Obrazek_11 - Change in the content of volatile combustible components and fixed carbon during CC-RED and RMS pyrolysis (a) Mass balance of CC-RED and RMS biomass pyrolysis products for pyrolysis temperatures of 500, 600, and 700°C (b)
Obrazek_11 - Reality photo of a microwave unit for controlled pyrolysis of biomass and waste materials equipped with a switching microwave source for precise temperature control in the reactor
Obrazek_12 - Photo of a microwave unit for controlled pyrolysis of biomass and waste materials

The schematics of individual stainless steel parts are listed in the following order:
Schema_1: Main reactor vessel – elevation
Schema_2: Main reactor vessel – floor plan
Schema_3: Main reactor lid – elevation  
Schema_4: Waveguide – elevation and side view  
Schema_5: Elbow – elevation  
Schema_6: Absorber – elevation  
Schema_7: Absorber cover – elevation and floor plan  
Schema_8: NZ 29/32 steel-glass transition piece – elevation 
Schema_9: Cooler – front view
Schema_10: Transition piece between elbow and cooler – front and side views

Proximate analysis was done for CC-RED and RMS according to the ASTM D7582 standard (LECO, TGA 701) consisted of the moisture (wt.%), volatile matter (wt.%), fixed carbon (wt.%), and ash content (wt.%) determination. Ultimate analysis was measured according to the Standard ASTM D3172-13 and D5373-16 (LECO CHNS 628, LECO AC 350) were done for CC-RED-RM and RMS-RM as well. 

Proximativni_Proximate_analysis_was_done_for_CC-RED_and_RMS_according_to_the_ASTM_D7582_standard_LECO_TGA_701_consisted_of_the_moisture_wt.%_volatile_matter_wt.%_fixed_carbon_wt.%_and_ash_content_wt.%_determination 
CHNO_Ultimate_analysis_was_measured_according_to_the_Standard_ ASTM_ D3172_13_and_D5373_16_LECO_CHNS_628_LECO_AC_350

Nitrogen physisorptions on all samples at 77 K were performed on a 3Flex instrument (Micromeritics, USA). The measurements were preceded by drying and degassing the samples (~0.05-0.08 g) at 350 °C under vacuum (< 1 Pa) for 24 h. Specific surface area, SBET, was determined based on the Brunauer-Emmett-Teller (BET) theory [1] for a range of relative pressures p/p0 = 0.05-0.25. The micropore volume, Vmicro, and mesopore surface area, Smeso, were evaluated by the t-plot method using the standard Carbon Black STSA isotherm. Total pore volume, Vnet, was determined from the N2 adsorption isotherm for a maximum relative pressure of p/p0 = 0.99. Mesopore and macropore size distributions were evaluated using the Barret-Joyner-Halenda (BJH) method [2], using Roberts algorithm [3] and the standard Carbon Black STSA isotherm with Faas correction. The micropore size distribution was evaluated from the low-pressure part (10-8 < p/p0 < 0.05) of the N2 adsorption isotherm using the Hovarth-Kawazoe method [4]. 

CC-RED-600_nitrogen_physisorptions
CC-RED-700_nitrogen_physisorptions
RMS-600_nitrogen_physisorptions
RMS-700_nitrogen_physisorptions

1.	Brunauer, S., P.H. Emmett, and E. Teller, Adsorption of Gases in Multimolecular Layers. Journal of the American Chemical Society, 1938. 60(2): p. 309-319.
2.	Barrett, E.P., L.G. Joyner, and P.P. Halenda, The Determination of Pore Volume and Area Distributions in Porous Substances. I. Computations from Nitrogen Isotherms. Journal of the American Chemical Society, 1951. 73(1): p. 373-380.
3.	Roberts, B.F., A procedure for estimating pore volume and area distributions from sorption isotherms. Journal of Colloid and Interface Science, 1967. 23(2): p. 266-273.
4.	Horv, et al., Method For the Calculation of Effective Pore Size Distribution in Molecular Sieve Carbon. Journal of Chemical Engineering of Japan, 1983. 16(6): p. 470-475.