TG Analysis on Burning Characteristic of Food Waste Ethanol Fermentation Residue Mixed with Coal

Abstract:

In order to reduce and re-utilize the ethanol fermentation residue from food waste, this study utilized residues to produce solid biomass fuel and carried out burning test by thermal gravity (TG) analysis. The results demonstrated that the residue from food waste shared the characteristic of high volatile content, high heat potential, low fixed carbon and low ash content. The burnable content was about 86.99% based on dry mass, while the heat potential was 23.06 MJ•kg^-1. Lignitous coal or blind coal was adopted as the additive to improve the burning characteristic of the fermentation residue. The result for a mixture of lignitous coal and residue was better than those of blind coal with the increase of complex burning index S from 2.38E-07°C^-3•min^-2 to 7.99E-08°C^-3•min^-2, decrease of ignition point, enhancement of average burning ratio and amelioration of burning characteristic. All these provided theoretical guidance for fermentation residue utilization as the solid fuel.

• Periodical: Applied Mechanics and Materials (Volumes 71-78)
• Pages: 3147-3150
• DOI: https://doi.org/10.4028/www.scientific.net/AMM.71-78.3147
• Online since: July 2011
• Authors: Wei Su, Hong Zhi Ma, Ming Gao, Jin Li, Qun Hui Wang
• Keywords: Co-Combustion, Ethanol, Fermentation Residue, Food Waste, Thermal Analysis

References

[1] Where Rmax was the maximum combustion rate, % / min; Rmean was the average burning rate,% / min. Complex combustion index fully reflected the ignition and burning properties of the sample, the more the S, the better the burning performance [[7] Zhou Yang,San Andres L,Childs D.W., Dynamic force performance of annular gas seal at off-center conditions, Tribology Transactions, 37 (1994) 33-42. ,[8] Nie Q H,Sun S Z,LI Z Q,Zhang X J,Wu S H,Qiu Y K, Thermo gravimetric Analysis on the Combustion Characteristics of Brown Coal Blends, Journal of Combustion Science and Technology, 7 (2001) 72-76. ]. The complex combustion index and burning properties for fermentation residue were shown in table 3 below. Table 3 Characteristic parameters obtained from TG, DTG, DSC and Tr curves corresponding to the combustion of fermentation residue Sample Ti [oC] Tmax1 [oC] Tmax2 [oC] Th [oC] Rmean [%·min-1] S[oC-3·min-2] Fermentation Residue 224.48 308.93 470.50 697.90 1.30 1.75E-07 Table 3 showed that the ignition point for the fermentation residue was as low as 223.48 oC, easy to be burned. The burnout temperature reached 697.90oC. This was same with the result for industrial analysis and DSC/DTG-Ts analysis in table 1. The high-volatile compounds in the fermentation residue were released quickly during burning process, thus a low ignition point. The low fixed carbon made it difficult to be burned out in the latter, thus it was unsuitable to use directly as a fuel for combustion. Additives should be used to improve its burning characteristic. Combustion characteristics for mixture with fermentation residue and coal. Residue was mixed with lignite or anthracite at the rate of 1:1. Specimens were used for thermal analysis. Corresponding results were showed in Figure 2 and 3.  Fig.2 Combustion TG, DTG curves for Fig.3 Combustion TG, DTG curves for residue mixed with lignitous coal residue mixed with anthracite coal Figure 2 and 3 compared the lignite and anthracite combustion respectively. The mixture had a higher volatile component, weight loss in TG was significantly putting ahead with a lower ignition point and the ration for ash at the final burning of the reaction decreased. That meant the burnable components increased. DTG curves had more peaks and were more complex, the trend was more flat. The mixture and the single components were demonstrated in table 4. Table 4 Characteristic parameters obtained from TG, DTG curves corresponding to the combustion of fermentation residue, Anthracite and their blends Sample Ti