| The wine distillers' grains is auxiliary product of brewing industry. There are many studies on its application, but its resource utilization is not ideal. And the accumulation of the wine distillers' grains is easy to rotten and result in polluting the environment. As one of the coal-rich provinces in China, Guizhou has abundant anthracite coal resources. However, the anthracite coal's characteristic is low volatile, high ash, and low ignition point, which makes it difficult to use. So it is of great significance to find a way to make it used effectively and cleanly on energy conservation, environmental protection and economic. Preparing distillers' grains coal water slurry(hereinafter referred to as JZ-CWS) by blending distillers' grains with Guizhou anthracite, can make use of the coordination effect possibly exists in the distiller's grains and coal, improve the combustibility of anthracite and reduce the coal consumption. Also this work makes good use of biomass resources and solve the problem of recycling use the waste distillers' grains. This article studied and discussed the slurry ability and combustion characteristics of JZ-CWS, mainly includes the following aspects:(1) To explore the slurry ability of JZ-CWS, this paper measured the different conditions of preparing JZ-CWS, including the blending proportion of distillers' grains, the kind and amount of additives, the concentration of coal slurry and the apparent viscosity, the drainage rate, the rod drop rate at different shearing velocity. The results showed that the viscosity reduction effect of MF was better than that of NNO and LS had the worst efficiency, with the increasing of dispersant's content, the viscosity of JZ-CWS decreased, and the best viscosity reduction effect was achieved when the content of the dispersant was 0.5%; The JZ-CWS performance changed the thin condition for cutting, and it belonged to Bingham Plastic fluid; The maximum plasma concentration of the anthracite is 70%, when the dispersant was 0.5% MF, and the apparent viscosity was 1000mPa?s, but the adhesive concentration of JZ-CWS was 65.8% when the distillers' grains blending proportion was 3%, and its stability was over 3d. When the JZ-CWS concentration was 62%, the maximum blending proportion of distillers' grains was lower than 9%, but the fluidity of slurry was very poor. JZ-CWS which blended with 7% grains has better comprehensive performance in fluidity and stability. The addition of distiller's grains makes the viscosity of coal tar increase remarkably, and enhances the coal tar stability. From the IR and SEM analysis we can see that the distillers' grains contains a large number of hydrophilic oxygen-containing functional groups and the surface porosity extremely develops, which are the main factors influencing the slurry performance of JZ-CWS.(2) The distillers' grains were modified by oil immersion method and chemical method in different soaking time, solution concentration and additive conditions, and the distillers' grains' pulping and blending effects were compared before and after modification. After the oil immersion modification, the effect on viscosity is not obvious, which mainly because the vegetable oil viscosity is too big to seal off the distiller's grains' surface pore completely, and causes the pellet accumulation easily. After modified by 5% Fe2(SO4)3 and 10% NaOH, the maximum blending proportion increased from below 9% before the modification to around 11% when the JZ-CWS concentration was 62%; Unmodified distillers' grains pulping maximum concentration was 56.1%, which cannot meet the requirements of coal water slurry, however, the maximum concentration of two kinds of solution were up to 60.2% and 61.1% respectively after modified while the blending proportion was 9%. Therefore chemical method modification made the viscosity of JZ-CWS reduce obviously, and enhanced the slurry ability greatly, the reason is that the metallic ion in the solution complexed with the –OH in distiller's grains, and the solution destroyed the lignin and cellulose in distiller's grains, which weakened the distiller's grains' infiltration capacity.(3)Through the study on combustion characteristics of JZ-CWS by thermogravimetric analysis experiment, we can find that the weight loss process of the coal slurry with 3% and 7% distiller's grains blending was similar to CWS which has no distillers' grains. The process includes dehydration, volatile matters separation and the fixed carbon combustion. The ignition temperature of JZ-CWS with 0, 3%, 7% distiller's grains blending is 547?, 517? and 480? respect, the ignitable index is 7.637, 8.635, 10.556%?min-1??-2, the synthesis combustion characteristic index is 6.676?8.149?10.675%2?min-2??-3. Therefore with the increase of distiller's grains blending proportion, the ignition temperature of JZ-CWS reduces obviously, but ignitable index C and synthesis combustion characteristic index S increases, which showed that the addition of distillers' grains improved the coal slurry combustion performance; According to the dynamic analysis with the Coats- Redfern method, we can see that the combustion activation energy E of JZ-CWS with 0, 3%, 7% distiller's grains blending was 77.837, 74.003, 70.869KJ?mol-1 respectively, and it decreases with the increasing of distillers' grains proportion. From the SEM?EDS and ash components analysis we can find that the blending of distiller's grains promoted coal slurry combustion performance, which mainly because the volatiles in distillers' grains escaped to fixed carbon pore, and the volatile matter burnt ahead of time improved the condition of fixed carbon to catch fire. In addition, there are many alkali metals in distillers' grains' ash and their catalytic action can reduce the activation energy of JZ-CWS. |
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