Zhijia Liu

Combustion characteristics of bamboo-biochars

Combustion characteristics of biomass are very important to directly utilize as an energy resource. Bamboo was carbonized using a XD-1200N muffle furnace in the nitrogen environment and its combustion characteristics were investigated. Results showed that bamboo-biochars had better combustion characteristics compared to bamboo materials, such as a lower content of moisture and volatiles, a higher energy density, HHV and EHC, a lower H/C and O/C ratios and a shorter TTI. Characteristic peak of bamboo-biochars shifted to higher temperature in thermal decomposition process, indicating a more steady-state burning and a higher combustion efficiency. Bamboo-biochars had a low content of S and N, which was helpful to decrease pollutant emissions. A higher content of K and Na was observed in the ash of bamboo-biochars, resulting in slagging, fouling, corrosion and agglomeration. The data from this research will be very helpful to efficiently design and operate its combustion systems.

Investigating pyrolysis and combustion characteristics of torrefied bamboo, torrefied wood and their blends.

Bamboo and masson pine was torrefied with 300°C of temperature for 2.0h of residence time using GSL 1600X tube furnace in the argon atmosphere. Torrefied bamboo and masson pine particles were uniform mixed with different weight ratios. Pyrolysis and combustion characteristics were investigated through thermogravimetry (TGA). The results showed that pyrolysis and combustion process of all samples included three steps even though their characteristics were different. Torrefied biomass had a higher pyrolysis and combustion temperature, due to moisture and volatile removal and thermal decomposition of hemicelluloses, cellulose and lignin during torrefaction process. Torrefaction also increased high heating value, ash content and C/H and C/O ratio of biomass. The synergy of torrefied bamboo and torrefied mason pine was not found during pyrolysis and combustion process of blends. The results from this research will be very important and helpful to develop and utilize the wastes of masson pine and bamboo for energy products.

Investigating pyrolysis characteristics of moso bamboo through TG-FTIR and Py-GC/MS

This study was carried out to investigate pyrolysis characteristics of moso bamboo (Phyllostachys pubescens), including outer layer (OB), middle layer (MB) and inner layer (IB) and bamboo leaves (BL), through TG-FTIR and Py-GC/MS. The results showed that 70% of weight loss occurred at rapid pyrolysis stage with temperature of 200-400 °C. With increase in heating rate, pyrolysis process shifted toward higher temperature. IB, OB, MB and BL had a different activation energy at different conversion rates. BL had a higher activation energy than IB, OB and MB. The volatiles of bamboo was complicated with 2-30 of C atoms. IB, OB and MB mainly released benzofuran, hydroxyacetaldehyde and 2-Pentanone. BL released furan, acetic acid and phenol. The main pyrolysis products included H2O, CH4, CO2, CO, carboxylic acids, NO, NO2. Pyrolysis products of IB was the most and that of BL was the lowest. MB had the lowest pyrolysis temperature.

Investigating co-combustion characteristics of bamboo and wood

To investigate co-combustion characteristics of bamboo and wood, moso bamboo and masson pine were torrefied and mixed with different blend ratios. The combustion process was examined by thermogravimetric analyzer (TGA). The results showed the combustion process of samples included volatile emission and oxidation combustion as well as char combustion. The main mass loss of biomass blends occurred at volatile emission and oxidation combustion stage, while that of torrefied biomass occurred at char combustion stage. With the increase of bamboo content, characteristic temperatures decreased. Compared with untreated biomass, torrefied biomass had a higher initial and burnout temperature. With the increase of heating rates, combustion process of samples shifted to higher temperatures. Compared with non-isothermal models, activation energy obtained from isothermal model was lower. The result is helpful to promote development of co-combustion of bamboo and masson pine wastes.

Pyrolysis characteristics of cellulose derived from moso bamboo and poplar

AbstractTo compare with pyrolysis characteristics of cellulose from moso bamboo and poplar, samples were pyrolyzed with different heating rates through thermogravimetric analysis (TG). The kinetics was calculated by Kissinger–Akahira–Sunose method. The results showed that pyrolysis process of moso bamboo and poplar fiber included three stages, and the main pyrolysis occurred in the second step. Moso bamboo fiber had a higher start temperature, a lower end temperature and a more mass loss at each heating rate in the main pyrolysis stage. With increase in heating rate, the temperature corresponding to the maximum of mass loss increased and the DTG curve shifted to higher temperature. The reaction rates varied at different heating rates. The activation energy of cellulose from moso bamboo was lower than poplar cellulose, indicating cellulose of moso bamboo was easier to be pyrolyzed. The results from this research will provide guidance to thermal conversion of moso bamboo and poplar.

Combustion characteristics of moso bamboo (Phyllostachys pubescens)

This study was carried out to investigate combustion characteristics of moso bamboo, including outer layer (OB), middle layer (MB) and inner layer (IB) and bamboo leaves (BL), respectively. The results showed that combustion characteristics of moso bamboo were similar to other biomass materials. There were two separate peaks in the combustion process; the first peak corresponding to combustion of volatile matters and the second peak corresponding to combustion of biochar. Compared to OB, MB and IB, BL had a worse fuel quality with higher H/C and O/C value, N and S content, ash content and lower combustion efficiency. Furthermore, BL had a higher slagging index and MB had a higher fouling index. These combustion characteristics of bamboo should be taken into consideration to efficiently design and operate the combustion systems when directly used for fuel production.

Economic analysis of a hypothetical bamboo-biochar plant in Zhejiang province, China:

Significant quantities of bamboo waste are generated in Zhejiang province, China. Many small businesses in this area convert this waste to biochar for use as a cooking fuel (in residential barbecues). This case study was conducted to evaluate the potential economic benefits of building and operating an industrial-sized plant in this province, yielding 500 tonnes per year. The researchers developed a conceptual design for a hypothetical biochar plant and then calculated net present value (NPV), investment payback period (PBP), internal rate of return (IRR), and sensitivity analysis. Results show that the static investment PBP would be 2.58 years, the IRR would be 38.8%, and the NPV would be US

Fire Performance of Poplar and Bamboo Curtain Veneers Treated with Fire Retardants

486,700. The IRR would be higher than the forestry industry benchmark (11%), indicating that a production line of bamboo-biochar with the stated yield not only could generate higher profits, but also could achieve a better return on investment. Thus, this study indicates that there are good market prospects for the bamboo-biochar industry in this region. The influence of sales prices on the IRR was more than that of operational costs, indicating that a large-scale plant should be designed to produce a high-quality bamboo-biochar. Supply chain issues such as transportation distances between locations where bamboo wastes are generated and the biochar plant should be considered in advance when siting new bamboo-biochar plants. The results from this research provide guidance to those considering development of bamboo-biochar plants in other parts of China.

The pyrolysis characteristics of moso bamboo

Bamboo curtain and poplar veneers, which are used as decorative building materials, were impregnated using two types of fire retardants (A and B) at atmospheric pressure in order to investigate fire retardancy using a cone calorimeter. When the impregnation time was longer, the fire retardancy was enhanced in the decorative material samples. When poplar veneer was treated by fire retardant A with impregnation times of 8 h, 16 h, and 24 h, the peak of heat rate release (pk-HRR) decreased by 41%, 51%, and 50%; the total heat release (THR) values decreased by 61%, 69%, and 75%; the total suspended particulates (TSP) values decreased by 90%, 82%, and 72%; and mass residues increased by 39%, 41%, and 43%, respectively. Treated bamboo curtain veneer had a lower fire retardancy when compared to poplar veneer. When bamboo curtain impregnation times were 8 h, 16 h, and 24 h, their pk-HRR values decreased by 37%, 45%, and 51%; the THR values decreased by 32%, 39%, and 44%; the TSP values decreased by 69%, 57%, and 78%; and the mass residues increased by 26%, 28%, and 29%, respectively. The results from this research should help to develop bamboo curtain veneer as an indoor decorative material.