Study objective

Operating condition

Feedstock type



To determine the influence of production conditions on the yield and environmental stability of biochar

pyrolysis temperatures:

350˚C - 550˚C;

heating rate:

8˚C min−1;

holding time: 60 min

pine, mixed larch and spruce chips, softwood pellets

・ biochar stability increases with increasing pyrolysis temperature;

・ the yield of biochar decreases with the peak pyrolysis temperature


To investigate the effect of pyrolysis temperature and heating rate on biochar from pyrolysis of safflower seed press cake

temperatures:400˚C, 450˚C, 500˚C, 550˚C and 600˚C

heating rates: 10˚C, 30˚C and 50˚C min−1

20 g of biomass

samples (SPC)

safflower seed press cake

・ at 600˚C biochar has highest fixed carbon content, FC (80.7%), carbon (73.8%), higher heating value, HHV (30.3 MJ∙kg−1) and lowest volatile matter content, VM (9.80%);

・ biochars had low BET surface areas (1.89 - 4.23 m2/g) containing predominantly aromatic compounds;

・ biochar yield decreased linearly with increasing temperature;

・ increase in heating rate reduced VM, FC and BET surface area but had no clear effect on HHV, elemental composition and pH


To determine the physical and thermochemical characterization of rice husk char as a potential biomass energy source


200˚C - 650˚C

heating rate: 50˚C

holding time: 60 min

rice husk

・ 400˚C the optimum temperature with char having moderate HHV;

・ order of reaction in combustion zone was ~1, the activation energy 73.4 kJ/mol with pre-exponential factor 4.97 × 104 min−1


Characterization of char from rapid pyrolysis of rice husk

・ temperature: 1200˚C

・ rice husk particles injected into the centre of the reactor at extremely high heating rates (≈1 × 104˚C/s), short residence times under a N2 environment at atmospheric pressure

rice husk

・ based on SEM, pore surface of char particle became increasingly rough in the middle of pyrolysis;

・ the surface area of char increased with pyrolysis process to a maximum value of 56.95 m2/g at pyrolysis reaction ratio (Rp = 0.90);

・ the H/C, O/C and N/C ratios of the char changed with different trends when the pyrolysis reaction ratio increased;

・ FTIR studies indicated a gradual decrease in the intensities of OH, C-H and C-O stretches with pyrolysis process


Characterization of biochars to evaluate recalcitrance and agronomic performance

・ pyrolyzing the feedstocks in 50˚C increments from 300˚C to 600˚C

・ holding at the target temperature: 15 - 20 min

・ about 3 kg of feedstock manually placed into main chamber purged with N2 while running the mixer

Bull manure, corn, dairy manure, hazelnut, oak, pine and poultry manure

・ biochar ash contents varied from 0.4% to 88.2%, VM from 13.2% to 70.0%, and fixed carbon from 0% to 77.4% (w/w);

・ pyrolysis temperature and FC increase proportionally for low-ash biochars, but decrease for biochars with >20% ash;

・ nitrogen recovery varied depending on feedstock used at a pyrolysis temperature of 600˚C;

・ at 600˚C, fixed carbon production ranged from no enrichment in poultry biochar to a 10-fold increase in corn biochar;

・ woody feedstock demonstrated the greatest versatility with pH values ranging from 4 to 9