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A low rank coal was first used to investigate the synergistic effect of inherent and loaded potassium and calcium ions on the pyrolysis behaviors. The non-isothermal thermal analysis with higher heating rate to medium pyrolysis temperature was carried out by thermogravimetric analyzer for the selected raw and treated coal samples. Preliminary experiments conducted show that the particle size smaller than 160 mm can eliminate heat and mass transfer effect, and the most of volatile matter was released by heating the raw coal (R-coal) to 750?C. Moreover, the effect of heating rate, inherent and loaded potassium and calcium on moisture evaporation and devolatilization is systematically investigated, and the devolatilization index is introduced to estimate the activity of pyrolysis pr?cess. A comparison among the acid pickling coal (H-coal), acid pickling coal loaded with calcium (H-coal-C), and potassium (H-coal-P) shows that potassium and calcium have improved the inner water holding capacity. Finally, the influence of inherent and loaded potassium and calcium on the kinetic characteristics of volatile matter release stage was studied with Coats-Redfern integral method.

The CO2 gasification of South Open-pit Mines coal from Zhundong Field of China using Ca(OH)2 or K2CO3 as catalyst with different loading methods and contents were conducted in thermogravimetric analysis. Comparison of the gasification reactivity and rate of coal loaded various concentration of Ca(OH)2 concluded that the increase of Ca(OH)2 loading pronouncedly improved the reactivity and rate for grinding method; nevertheless, for impregnation and high pressure method the increase of Ca(OH)2 loading observed a similar catalytic effect on char gasification. However, the catalytic effect of K2CO3 revealed that the catalytic activity increased with the increase of K2CO3 loading for three loading method. For the same catalyst loading, the highest catalytic gasification reactivity achieved for Ca(OH)2 and K2CO3 were the loading methods of high pressure and grinding, respectively. In addition, the gasification of raw char, K2CO3 loaded char and Ca(OH)2 loaded char were quantitatively evaluated by kinetic analysis using shrinking core, random pore and modified random pore models.

Biomass gasification in a dual fluidized bed has been regarded as one of the most promising technologies. The hydrodynamics play a vital role in determining the performance of a dual fluidized bed (DFB) system. In this study, based upon the solid-gas two phase theory, and pressure and mass balances, a hydrodynamic model for the DFB system was developed. The model parameters of mixed particles (rice husk and quartz sand) were fitted using the homogeneous and phase-separated particles model in order to improve the accuracy of predicted results. It was found that the predicted results were in reasonable agreement with the experimental results for the pressure drop, pressure distribution and circulation flow rate of the cold model of the DFB system. Which provides guidance for the operation and design of DFB gasifier equipment.

A novel solid-oxide-fuel-cell-based cooling, heating, and power (CCHP) system integrated chemical looping hydrogen generation is proposed, in which the chemical looping hydrogen generation realizes the high-efficiency CO2 capture and provides hydrogen to fuel cell, avoiding carbon deposition caused by the direct reaction of methane. The high-temperature solar heat collector is integrated to assist the fuel cell subsystem in achieving high-efficiency power generation and energy cascade utilization. The thermodynamic models of components are constructed, and the energy and exergy performances under the design conditions with or without solar energy are compared and analyzed. Through validating the thermodynamic models, the simulation results indicate that the energy and exergy efficiencies in cooling mode are 78.02% and 45.92%, respectively. The energy efficiency in heating mode reduces by 5.08%, while the exergy efficiency increases by 0.67%. The CO2 capture rate of the proposed system reaches 99.96% and the CO2 purity is about 99.59%. The energy consumption of CO2 capture in the proposed system reduces by 69.37% compared to the conventional system. The sensitivity analysis of key parameters such as fuel cell operating temperature and direct normal irradiance on system performances are performed. The results show the total energy and exergy efficiencies can be improved by properly increasing the SOFC operating temperature. Although the energy and exergy efficiencies slowly drop with the increasing direct normal irradiation, the energy output increases by 6.10% and 4.95% in cooling and heating mode from 500 W/m2 to 1000 W/m2, respectively.

The synergetic effects of firing gases/coal blends and simultaneously adopting deep air staging on combustion characteristic parameters, such as furnace temperature, burnout of coal and NOx emissions, were firstly experimentally studied and numerically simulated in a 300 MWe unit boiler. The improved multiple surface reaction model, which included pore diffusion resistance of gas phase in ash, was proposed in this paper to simulate actual char combustion. The simulated results quantitatively showed that the proposed model solved the problem of seriously inaccurate calculation of unburned carbon in fly ash for the numerical simulation of multifuel combustion. Under the conditions of firing coal/gases blends and adopting air staging, the models of pulverized coal pyrolysis, coke gasification and gas combustion were established because the reduction atmosphere is formed in the primary combustion zone of the furnace. The reduction of NOx by reductive gases produced from co-firing gases, pulverized coal pyrolysis and coke gasification was considered in numerical simulation. All the numerical models adopted in this study were reasonably validated on the basis of comparing the simulation and experimental results. The temperature field, velocity field, flue gas components, coke burnout, NOx formation and reduction characteristics of three conditions (coal-fired condition, adopting deep air staging condition and firing coal/gases blend and simultaneously adopting deep air staging condition) were studied numerically. After firing coal/gases blend and adopting deep air staging, the furnace temperature field was fairly well-distributed; the average velocity of flue gas decreased lower; the reducing atmosphere zone was found to be lengthened by comparing the concentration of oxygen and carbon monoxide; and it could be concluded that there was more time for the combustible matter burning-out and NOx reduction. The temperature field and reducing gases distribution profile along the furnace height are disadvantageous for generating NOx and beneficial to reducing NOx. The results clarified the complex synergistic effect of firing coal/gases blend and adopting deep air staging on combustion characteristics, which could be applied to increase the boiler performance and optimize the co-firing technology.

Effects of secondary air and separated overfire air on boiler performance were experimentally investigated in a 300 MWe utility boiler co-firing coal with blast furnace gas and coke oven gas. Moreover, an objective function aiming at simultaneously calculating NOx emissions and boiler efficiency from thirty-seven operating parameters was represented by a back propagation neural network model which was optimized by genetic algorithm, and the nineteen levels damper openings of secondary air and separated overfire air were optimized by adopting genetic algorithm so as to simultaneously achieve low NOx emissions and high boiler efficiency. Damper openings of secondary air located at blast furnace gas nozzles zone (GAA/GA/GBB) and coal combustion zone (AS/BS/CS and AA/AB/BC/CC) were adjusted from 10 to 100% in specially designed burner, and the better damper openings were experimentally obtained. The damper openings of separated overfire air were also changed from 10 to 100%, but it hard to evaluate the better damper openings due to the boiler efficiency and NOx emissions simultaneously decrease with the increase of separated overfire air. Finally, the optimal operation of secondary air and separated overfire air were achieved by using optimization model, which could provide references for the adjustment of secondary air and separated overfire air.

In the LIN(Local Interconnect Network) bus communication transmission, there is a problem of data transmission delay in the process of sending messages by the master-slave node ECU(Electronic Control Unit).Aiming at this kind of delay problem, this paper analyzes the characteristics of static scheduling and dynamic scheduling algorithm of LIN bus, optimizes the scheduling strategy of LIN bus message, and proposes a hybrid scheduling algorithm based on time slice scheduling. At the same time, the simulation model of LIN bus master-slave node message transmission is established, and the simulation experiment verification platform of LIN bus hardware-in-the-loop is built. It is verified that the algorithm reduces the delay by about 30%.

In order to more accurately simulate the flow characteristics of biomass particles in biomass gasification process, an experimental study was conducted on the circulating flow rate of rice husk-quartz sand mixture on a self-built dual circulating fluidized bed cold experimental system. The circulation flow rate increased with the increase of the gasification chamber wind speed (Ua), but the growth trend gradually slowed down. With the increase of the mass fraction of rice husk (Xr) in the mixed material, the circulating flow rate showed a decreasing trend under various operating conditions. The Xr in the circulating material basically showed a decreasing trend, and increased with the increase of the wind speed of riser (Ur).The trend of increase in the lower wind speed interval was larger. After a certain wind speed value was reached, the increase trend of particles gradually became slower, and the circulating material mass fraction Xr showed a decreasing trend, and the decreasing trend gradually increased; with the increase of the initial material mass (mint),the flow rate of material circulation increased to a certain extent. The Xr in the mixed material gradually increased. Under the conditions of the respective mass fraction of mixed material, the particle size of quartz sand(dp) in the mixed material increased, the circulating flow rate of the particles gradually decreased, and the mass fraction of biomass in the riser decreased gradually.

The method Hankel Total Least Squares (HTLS)-PK, which successfully incorporates prior knowledge of known signal poles into the method HTLS, has been proven to greatly improve the performance for parameter estimation of overlapping peaks of magnetic resonance spectroscopy (MRS) signal. In addition, decimation is also proposed as a way to increase the performance of subspace-based parameter estimation methods in the case of oversampling. Taking advantage of decimation in combination with prior knowledge to estimate the MRS signal parameters, two novel subspace-based parameter estimation methods, HTLSDSumPK and HTLSDStackPK, are presented in this paper. The experimental results and relevant analysis show that the methods HTLSDSumPK, HTLSDStackPK and HTLS-PK are slightly better than the method HTLS at low noise levels; however, the three prior-knowledge-incorporating methods, especially the method HTLSDSumPK, have much better performance than the method HTLS at high noise levels in the terms of robustness, estimated accuracy and computational complexity. Even if some inaccuracy of prior knowledge is considered, the method HTLSDSumPK also shows some advantages.