Studies On The Optimization Method And Model Prediction And Improving Slurrying Mechanism Of Shenhua Coal Water Slurry's Slurrying Characteristics

CWS(Coal Water Slurry) which makes use of coal instead of oil is a new kind of clean fuel which is development from the 1970s oil crisis.This technology's application not only gives the fuel oil enterprise to bring the obvious economic efficiency, but also play a very important role in saves oil resource and optimizing and improving energy structure.CWS is a complicated multistep dispersive suspension system, so there are many complx factors influencing the slurrying and rheological characteristics of CWS.The CWS's preparation is the key to the CWS technology.So the research on CWS's preparation has important practical significance.Firstly, factors and mechanics which influence the slurrying characteristics of CWS are studied in this article. There are many factors, such as the nature of coal, preparation technology, the size distribution the type and quantity of addition agent, and so on. At the same time, the methods to improve the slurryability were discussed, such as low temperature pyrolysis treatment, mixture of different coals, particle size grading technology, ultrasound technology, microwave technology, electromagnetic field magnetic technology and high-pressure hot water treatment technologies.Secondly, the slurrying characteristics of six typical gasification coals are studied.A suitable type of additives, the best amount of additives and the largest concentration of CWS were found.The particle pore structure and coal quality ingredients influent to the concentration of CWS is analyzed.As the high-concentration CWS of shen hua is very difficult to parpation, the article using SAS software to the linear regression analysis after orthogonal test, get the regression equation, and then through a computer program optimization, get a better paticl size distribution and amount of additives. Through optimization the characteristic of CWS have greatly improved, the highest concentrations enhance from 59.51 percent to 62.76 percent, and the stability and liquidity are better. On this basis, using multiple linear regression and non-linear regression optimization, get a better correlation coefficient and a better particle size distribution and the concentration increase 0.29 percent than the orthogonal test optimization.Using R-R and Alfred model to prepare CWS, and compared with two kind of gradation hydromass's performance, and find out the model which adapts with each kind of coal.The results showed that: concentration increased 3～5%, the slurryability of R-R model is better than Alfred model, and the former more easily applied. in project The R-R model isn't suitable for Baodian and Shenhua coal, but suitable for Yangzhuang, Xinglong and Huainan coal.Finally, use high-pressure hot water reactor to improve the slurrying characteristics of Shenhua: internal moisture and oxygen-containing functional groups reduce; H-containing increase; O/C has a certain degree of decline, and volatile precipitated.The BET surface area, the total pore volume and the average diameter holes of coal have been reduced, and the particles fractal dimension has increased. The modification has the most obvious changes in 10 minutes, and the concentration enhance from 59.51 percent to 63.72 percent, and with the modification time increase, the concentration has a downward trend.