An coordinated control strategy has been proposed and successfully applied to 300MW circulating fluidized bed (CFB) units in China. The paper describes the new coordinated control (NCC) system to overcome the long settling time, strong coupling, nonlinearity and inconstancy encountered in CFB combustion. NCC is based on both fuzzy Feedforward (fuzzy-FF) control and the fuzzy-PID feedback contro...

in this paper, combustion of char in the riser of circulating fluidized bed was modeled using aspen plus. since physical and chemical phenomena are involved in the process, the model integrates the two-phase hydrodynamic sub-model with the reaction sub-model derived from the literature. in the proposed model, the fluidized bed is divided into several sections and the behavior of each section wa...

Abstract The paper presents the results of operational measurements suspension density distribution in 966 MW th supercritical Circulating Fluidized Bed boiler. tests were carried out for four different unit thermal loads, i.e. 40, 60, 80, and 100% MCR. conducted showed that particulate material combustion chamber CFB boiler has form an exponential curve with maximum values occurring bottom par...

The paper describes the ongoing work on modeling and simulation of energy conversion processes. The models have been implemented in Modelica language and simulated in Dymola environment. The studied processes are a biomass fired Circulating Fluidized Bed (CFB) boiler and an anaerobic digester for biogas production. The models were validated towards real process data. The models have been runnin...

Circulating fluidized bed (CFB)-based coal burning technology is a type of clean combustion technology. Owing to its characteristics low temperature and desulfurization in furnace, the CFB fly ash quite different from ordinary ash. Based on comprehensive understanding physical chemical ash, this review summarizes research progress application Portland cement, magnesium oxysulfate (MOS) solid-wa...

Fast pyrolysis of hydrolysis lignin was studied in fluidized bed units. Hydrolysis lignin, a bioproduct from the lignocellulosic ethanol production process (St1 Cellunolix), processed bench scale bubbling (BFB) and pilot circulating (CFB) Utilization steam as hydrogen sources tested BFB unit. Major technical challenges identified were related to slow reaction rates degradation rapid secondary r...

The underlying objective of the present study is to increase gas-solids contact in a circulating fluidized bed by the introduction of obstacles in the riser portion. The presence of such obstacles leads to suppression of radial inhomogeneities in the solids mass flux and concentration, and break-up of solids clusters. At ambient conditions, gas-solids mass transfer was investigated for cocurren...

To monitor the gas and solid streams in a downcomer of a J-valve in a CFB, the simultaneous measurement technique using the oxygen gas tracer, the hot particle tracer and the pressure drop was developed. By using this novel measurement technique, the dependence of the solid flow on the gas flow in the moving bed in the downcomer of J-valve was investigated. The pressure profile and the pressure...