Value-added performance of processed cardboard and farm breeding compost by pyrolysis.

This study aims to underline the huge potential in Canada of adding value to cardboard and compost as a renewable fuel with a low ecological footprint. The slow pyrolysis process of lined cardboard and compost blend was investigated. Thermal behavior was investigated by thermogravimetric analysis coupled with mass spectrometry (TGA-MS). The thermal profiles are presented in the form of TGA/DTG curves. With a constant heating rate of 10 °C/min, two parameters, temperature and time were varied. Cardboard decomposition occurred mostly between 203 °C and 436 °C, where 77% of the sample weight was decomposed. Compost blend decomposition occurred mostly between 209 °C and 373 °C, with 23% of weight. The principal gaseous products that evolved during the pyrolysis were H2O, CO and CO2. As a result, slow pyrolysis led to the formation of biochar. High yield of biochar from cardboard was found at 250 °C for a duration of 60 min (87.5%) while the biochar yield from the compost blend was maintained constant at about 31%. Finally, kinetic parameters and a statistical analysis for the pyrolysis process of the cardboard and compost samples have been investigated. Both materials showed a favorable thermochemical behavior. However, unlike cardboard, compost pyrolysis does not seem a promising process because of the low superior calorific and biochar values.

Efficient and simple method for determination of suspendibility of bio-inoculant suspensions.

This study assessed the utilization of viscosity and zeta potential as a novel method to evaluate suspendibility of formulation of Sinorhizobium meliloti grown in starch industry wastewater for use as bio-inoculants. For this objective, sorbitol was used as a suspending agent at concentrations of 0 to 10% w/v. Model, based on multiple linear regression (with pH as dependant variable, and zeta potential, average particle size and sorbitol concentration as independent variables) demonstrated an important relation which was significant (p<0.001, R2=0.98). Sigmoid regression revealed a significant relation between zeta potential and suspendibility with p value=0.007 and R-squared=0.86, and between viscosity and suspendibility (p value<0.0001 and R squared=0.9823). Thus, these direct correlations established the lowering of measurement time from 12 h to 5 min.