Shiwen Fang

Effects of additives on the co-pyrolysis of municipal solid waste and paper sludge by using thermogravimetric analysis.

By using thermogravimetric analysis (TGA), the effects of different additives (MgO, Al2O3 and ZnO) on the pyrolysis characteristics and activation energy of municipal solid waste (MSW), paper sludge (PS) and their blends in N2 atmosphere had been investigated in this study. The experiments resulted that these additives were effective in reducing the initial temperature and activation energy. However, not all the additives were beneficial to reduce the residue mass and enhance the index D. For the different ratios of MSW and PS, the same additive even had the different influences. The catalytic effects of additives were not obvious and the pyrolysis became difficult with the increase of the proportion of PS. Based on all the contrast of the pyrolysis characteristics, MgO was the best additive and 70M30P was the best ratio, respectively.

A study on microwave-assisted fast co-pyrolysis of chlorella and tire in the N 2 and CO 2 atmospheres

The microwave-assisted fast co-pyrolysis of chlorella and tire with additive under N2 and CO2 atmospheres were investigated. The pyrolysis profiles, yields of three-phase, the chemical composition of liquid and the ultimate analyses of solid residues were gained. With the tire ratio increasing, all the characters had the changes. The finial temperature had a wave change. The yield of liquid decreased and the chemical composition obtained in liquid of oxygenates compounds decreased, while hydrocarbon compounds increased, among which aromatic hydrocarbons had the highest content. The yield of solid increased, the HHV had a wave change and the values of H/C decreased. Under CO2 atmosphere, the final temperatures were lower with 70% and 100% chlorella ratios, the yield difference of liquid reached the minimal with 70% and 30% chlorella ratios. According to the quantity and quality of liquid and solid, and the former results, 50% percentage of tire was the suitable ratio.

Co-pyrolysis kinetics of sewage sludge and bagasse using multiple normal distributed activation energy model (M-DAEM)

In this study, the kinetic models of bagasse, sewage sludge and their mixture were established by the multiple normal distributed activation energy model. Blending with sewage sludge, the initial temperature declined from 437 K to 418 K. The pyrolytic species could be divided into five categories, including analogous hemicelluloses I, hemicelluloses II, cellulose, lignin and bio-char. In these species, the average activation energies and the deviations situated at reasonable ranges of 166.4673-323.7261 kJ/mol and 0.1063-35.2973 kJ/mol, respectively, which were conformed to the references. The kinetic models were well matched to experimental data, and the R2 were greater than 99.999%y. In the local sensitivity analysis, the distributed average activation energy had stronger effect on the robustness than other kinetic parameters. And the content of pyrolytic species determined which series of kinetic parameters were more important.

Ultrasonic pretreatment effects on the co-pyrolysis of municipal solid waste and paper sludge through orthogonal test

In this study, the influences of ultrasonic pretreatment factors (frequency, power, treatment time) on blends of municipal solid waste (MSW) and paper sludge (PS) with additive (MgO) was explored, through orthogonal experiments design. The optimum operating condition wanted to be acquired. However, for the ultimate (H/C) and ash analysis after pretreatment, solid residue mass and oxygenates compounds contents in products, the influences of factors were in different results. With adding PS unceasingly, the contents of hydrocarbon compounds decreased. And the ultrasonic pretreatment had the obvious influence with high PS percentage. Longer treatment time resulted to the lower content of oxygenates compounds. After adding MgO, the residue mass reduced, which meant MgO had the catalytic action, and the oxygenates compounds content reduced only with 100 kHz, which had the sonochemical effect.