Hairui Yang
Tsinghua University
Publications 118
Abstract The thermal effects of five coal types' pyrolysis processes at heating rates of 5, 10, 15, 20, and 30 °C/min in the temperature range of 30–1000 °C were systemically investigated by thermogravimetric - differential scanning calorimetry. The experimental results show that coal pyrolysis process can be roughly divided into four stages, namely the drying and dehydration stage S1, the degassing stage S2, the pyrolysis stage S3, and the polycondensation stage S4. S1, S2, and S3 are endotherm...
Abstract The world first 550-MWe ultra-supercritical circulating fluidized bed (CFB) boiler is designed with integrated recycle heat exchangers (INTREX) and internal solid circulation. In this research, in order to investigate the heat transfer behavior and the significance of the internal circulation, the operation characteristics of the four INTREXes as final superheaters including heat transfer coefficients and ash flow rates under different load conditions are experimentally studied. The cal...
Abstract The classification performance of model coal mill classifiers with different bottom incoming flow inlets were experimentally and numerically studied. The flow field adjacent to two neighboring impeller blades were measured using the particle image velocimetry technique. The results showed that the flow field adjacent to two neighboring blades with the swirling inlet was significantly different from that with the non-swirling inlet. With the swirling inlet, there was a vortex located bet...
#1Yiqun Huang (THU: Tsinghua University)H-Index: 1
#2Man Zhang (THU: Tsinghua University)H-Index: 9
Last.Yan Jin
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Abstract Due to high ash content and anisotropy of bedding structure, the effects of ash thickness and bedding structure anisotropy on combustion of oil shale semicoke were crucial. A two-dimensional mathematical model of oil shale semicoke particle combustion was developed and validated by combustion experiments of cylindrical Huadian oil shale semicoke particles on the self-designed Macro thermal gravimetric analyzer (TGA), with a weighting capacity over 100 g. There was obvious anisotropy dur...
#1Shahong Zhu (THU: Tsinghua University)H-Index: 1
#2Man Zhang (THU: Tsinghua University)H-Index: 9
Last.Hairui Yang (THU: Tsinghua University)H-Index: 19
view all 5 authors...
Abstract As one of the most important auxiliary systems of a circulating fluidized bed boiler, the limestone pneumatic conveying system is of great significance to its operation. Maldistribution of powder in the different injecting ports seriously limits inner-furnace desulfurization performance owing to inefficient mixing of limestone powder and SO2. The gas–solid flow characteristics of an industrial-scale multiple-branching limestone-conveying pipeline system of a 200 MW circulating fluidized...
#1Dongfang Li (PNU: Pusan National University)H-Index: 1
#2Xiwei Ke (THU: Tsinghua University)H-Index: 1
Last.Man Zhang (THU: Tsinghua University)H-Index: 9
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Abstract The Samcheok CFBC (circulating fluidized bed combustion) power generation plant, the world largest, consists of 4 units of 550 MWe USC (ultra-supercritical) CFB boilers, started operation since the end of 2016. The years’ operation proves that there lacks circulating material and low solid hold-up in the upper furnace when burning Indonesia coal with low ash content of 4.5%. To solve this problem, the present study studied the mass balance of the Samcheok CFB boiler by investigating the...
#1Runxia CaiH-Index: 4
#2Yiqun HuangH-Index: 1
Last.Junfu LyuH-Index: 4
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Limestone particle size has a crucial influence on SO2 capture efficiency, however there are few studies on the sulfation reactivity, which covers a broad range of particle sizes at low SO2 concentrations. In this paper, a large-capacity thermogravimetric analyzer (LC-TGA) was developed to obtain the sulfur removal reaction rate under a wide range of particle sizes (3 μm–600 μm) and SO2 concentrations (250 ppm–2000 ppm), and then compared with the results of a traditional fixed bed reactor and a...
#1Yuge Yao (THU: Tsinghua University)
#2Runxia Cai (THU: Tsinghua University)H-Index: 4
Last.Junfu Lyu (THU: Tsinghua University)H-Index: 4
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Abstract It is very important to accurately measure the tube-wall temperature of the high-temperature heating surface in the boilers with high steam parameters such as supercritical circulating fluidized bed (CFB) boilers. However, the severe abrasion problem caused by high solid concentration in CFB boilers hinders a direct tube-wall temperature measurement in CFB boilers. In this paper, a new method which embeds thermocouples in deposited metal on the heating surface was proposed to solve this...