摘要:
For the stabilization of the reaction, especially, for maintaining reaction temperature, the feedback control by the feedback unit is performed for to the supply of air (, oxygen, or oxidizing agent), whereas other materials are supplied by the open-loop control according to the instruction of the flow selection unit which indicates a preset value depending on the required hydrogen production volume. In addition, the continuous flow setting unit capable of changing the flow continuously is employed for the supply system of the air, whereas the flow control of the other materials is performed by use of the discrete flow setting units each of which provides the discretized flow by use of the on-off combination of two or more on-off valves.
摘要:
In an exhaust gas treatment device provided with: an exhaust gas treatment unit in which an oxygen combustion boiler 1 using coal as fuel, a denitration device 3, an air preheater 4, a dust-collection device 5, a desulfurization device 6, and a carbon dioxide recovery device 8 are sequentially arranged from the upstream side to the downstream side of an exhaust gas duct; and an exhaust gas circulation unit which branches off from the exhaust gas duct at an outlet of the dust-collection device 5 or an outlet of the desulfurization device 6 and through which the exhaust gas is preheated by the air preheater 4 and returned to the oxygen combustion boiler 1, a heat-recovery heat exchanger 13 that adjusts a gas temperature at an inlet of the dust-collection device 5 to be not greater than an acid dew point of SO3 and not lower than a water dew point is provided between the air preheater 4 and the dust-collection device 5, a reheating heat exchanger 13 that adjusts a gas temperature to be not lower than the acid dew point of SO3 is provided in the vicinity of a branch of the exhaust gas circulation unit, adjusting the gas temperature at the inlet of the dust-collection device 4 to be not greater than the acid dew point of SO3 makes it possible to prevent corrosion of pipes in the exhaust gas circulation unit and to avoid a decrease in fluidity or combustibility of the pulverized coal in the pipes in the mill.
摘要:
A desulfurization device releases exhaust gas into the atmosphere without reduction in CO2 recovery rate and without mercury components. Because the absorbent of the desulfurization device is drawn from an absorbent reservoir by a circulating pump and sprayed through spray nozzles into a desulfurization-absorption unit and is mainly circulated outside the wall of a water seal tube by a stirrer in the absorbent reservoir, the flow of the absorbent that falls from the desulfurization-absorption unit into the water seal tube flows in a single direction from top to bottom and hinders the ascension of gas bubbles. Intermixing of the gas for oxidizing the sulfur dioxide with the desulfurization device exhaust gas is thereby prevented, efficient CO2 recovery is possible without reduction in the CO2 concentration recovered from the exhaust gas after desulfurization and mercury in the combustion exhaust gas is absorbed in the absorbent of the desulfurization device.
摘要:
In an exhaust gas treatment device provided with: an exhaust gas treatment unit in which an oxygen combustion boiler 1 using coal as fuel, a denitration device 3, an air preheater 4, a dust-collection device 5, a desulfurization device 6, and a carbon dioxide recovery device 8 are sequentially arranged from the upstream side to the downstream side of an exhaust gas duct; and an exhaust gas circulation unit which branches off from the exhaust gas duct at an outlet of the dust-collection device 5 or an outlet of the desulfurization device 6 and through which the exhaust gas is preheated by the air preheater 4 and returned to the oxygen combustion boiler 1, a heat-recovery heat exchanger 13 that adjusts a gas temperature at an inlet of the dust-collection device 5 to be not greater than an acid dew point of SO3 and not lower than a water dew point is provided between the air preheater 4 and the dust-collection device 5, a reheating heat exchanger 13 that adjusts a gas temperature to be not lower than the acid dew point of SO3 is provided in the vicinity of a branch of the exhaust gas circulation unit, adjusting the gas temperature at the inlet of the dust-collection device 4 to be not greater than the acid dew point of SO3 makes it possible to prevent corrosion of pipes in the exhaust gas circulation unit and to avoid a decrease in fluidity or combustibility of the pulverized coal in the pipes in the mill.