Numerical and experimental investigations of converter gas improvement inside a flue using its waste heat and CO₂ by pulverized coal injection

Abstract

To explore how to use the waste heat and reduce the CO2 emissions of converter flue gas, a new process is proposed in this paper, performed by injecting pulverized coal into the hot gas using its waste heat to generate CO and further to achieve a secondary recovery of flue gas. Numerical simulations and industrial investigations are conducted. By comparing the injecting rate, the particle size, and the injecting velocity of the pulverized coal, an optimized scheme was obtained. The testing results show that, with increasing the injecting rate, the O2 and CO2 contents in the flue gas are reduced, while the CO and H2 contents are increased. When the injecting rate is 20 kg min−1, the O2 and CO2 contents are decreased by 72.16% and 50%, respectively, yet the CO and H2 contents are raised by 21.08% and 171.8%, respectively. The gas recovery time is extended by 10.12% and the carbon conversion is increased as much as 55%. Thus, the new process will be of great benefit to reduce CO2 emissions and increase the energy of converter gas. © 2017 American Institute of Chemical Engineers Environ Prog, 37: 1503–1512, 2018

Energy Recovery Maximisation Modelling Subject to Constrained Cooling

“…These processes also produce an energy stream as a secondary product in the form of high-temperature flue gas [2]. The carbon-oxygen reaction within a BOF converter produces flue gas at temperatures between 1200 and 1500 • C [3].…”

An efficient and continuous filter operation for dust‐laden flue gas based on a self‐cleaning stainless steel weaved filter

“…High‐temperature dust‐laden flue gas discharged from industrial processes is a major source of fine particulates in the atmosphere, leading to serious air pollution 1–3 . Additionally, a large amount of waste heat is also emitted along with the flue gas 4–6 . High concentrations of dust particles cause dust deposition seriously on the surface of the heat exchanger tube bundle during the waste heat recovery process 7 .…”

“…[1][2][3] Additionally, a large amount of waste heat is also emitted along with the flue gas. [4][5][6] High concentrations of dust particles cause dust deposition seriously on the surface of the heat exchanger tube bundle during the waste heat recovery process. 7 It not only reduces the heat transfer performance of the heat exchanger, 8 but also causes uneven distribution of the internal temperature field of the heat exchanger, leading to the phenomenon of tube leakage, which seriously affects the stability, economy, and safety of the heat exchanger.…”

“…In filtration unit, replaceable SSWBs are wrapped around the tube with a support body. The flow rate of flue gas is measured by a float flowmeter (FF25 Kewill, Germany), and pressure drop is calculated by measuring the upstream and downstream pressures of the filter through manometers (P6 Kewill, Germany).The filtration superficial velocity u is defined as Equation(6).Based on the optimization results, the diameter and length of SSWB are constructed of 130 mm and 2000 mm, the diameter of filter shell of 165 mm, and the filtration area of 0.82 m 2 . The flow rate of flue gas is 0 $ 300 m 3 /h.…”