摘要:
Method for producing pulverized coal, the method comprising the steps of heating a drying gas, preferably an inert gas, in a hot gas generator (26) to a predefined temperature; feeding the heated drying gas into a pulverizer (20); introducing raw coal into the pulverizer (20), the pulverizer (20) grinding the raw coal into pulverized coal; collecting a mixture of drying gas and pulverized coal from the pulverizer (20) and feeding the mixture to a filter (34), the filter (34) separating the dried pulverized coal from the drying gas; collecting the dried pulverized coalfor further use and feeding the drying gas from the filter (34) to a recirculation line (38) for returning at least part of the drying gas to the hot gas generator (26); and determining an oxygen level in the drying gas, preferably in the recirculation line (38), and comparing the determined oxygen level to a predetermined oxygen level threshold. According to a preferred embodiment of the invention, if the determined oxygen level is higher than a predetermined oxygen threshold, water is injected into the heated drying gas before it is fed into the pulverizer (20), the volume of water injected being calculated so as to reduce the oxygen level below the predetermined oxygen level threshold.
摘要:
A device for continuously feeding a powdery solid out of a storage bin (10) and into a pneumatic conveying line (12, 12') comprises a first and a second intermediate vessel (14 and 16) that are placed adjacent to one another. The first intermediate vessel (14) is provided in the form of a sluice vessel having an upper sluice gate (18) and a lower sluice gate (20). The second intermediate vessel (16) is provided in the form of an injection vessel. A pneumatic intermediate conveyance (50) is placed between the lower sluice gate (20) of the first intermediate vessel (14) and an upper inlet (30) of the second intermediate vessel (16). This intermediate conveyance enables the powdery solid to be conveyed out of the first intermediate vessel (14) and into the second intermediate vessel (16).
摘要:
Method for producing pulverized coal, the method comprising the steps of heating a drying gas, preferably an inert gas, in a hot gas generator (26) to a predefined temperature; feeding the heated drying gas into a pulverizer (20); introducing raw coal into the pulverizer (20), the pulverizer (20) grinding the raw coal to pulverized coal; collecting a mixture of drying gas and pulverized coal from the pulverizer (20) and feeding the mixture to a filter (34), the filter (34) separating the dried pulverized coal from the drying gas; and collecting the dried pulverized coal for further use and feeding part of the drying gas from the filter to a recirculation line (38) for returning at least part of the drying gas to the hot gas generator (26). According to an important aspect of the present invention, the method comprises the further step of controlling an exit temperature of the mixture of drying gas and pulverized coal exiting the pulverizer (20) by controlling a volume of water injected into the heated drying gas before feeding it into the pulverizer (20).
摘要:
An injection system for solid particles comprises a conveying hopper (11) located at an upstream location (1), a fluidizing device (21) for fluidizing the solid particles at the outlet of the conveying hopper (11) and forming a solid-gas flow, a pneumatic conveying line (15) for conveying the solid-gas flow from the fluidizing device (21) to a downstream location (2) and a static distribution device (17) with a plurality of injection lines (19), connected thereto. An upstream flow control system controls the mass flow rate in the pneumatic conveying line (15) at the upstream location (1) by controlling the opening of an upstream flow control valve (35) responsive to the solid material mass flow measured in the pneumatic conveying line (15) at the upstream location (1). A downstream flow control system controls the mass flow rate in the pneumatic conveying line (15) at the downstream location (2) by controlling the opening of a downstream flow control valve (51, 79i) responsive to the instantaneous mass flow rate sensed by a main downstream mass flow rate sensor (53).
摘要:
An injection system for solid particles comprises a conveying hopper (11) located at an upstream location (1), a fluidizing device (21) for fluidizing the solid particles at the outlet of the conveying hopper (11) and forming a solid-gas flow, a pneumatic conveying line (15) for conveying the solid-gas flow from the fluidizing device (21) to a downstream location (2) and a static distribution device (17) with a plurality of injection lines (19), connected thereto. An upstream flow control system controls the mass flow rate in the pneumatic conveying line (15) at the upstream location (1) by controlling the opening of an upstream flow control valve (35) responsive to the solid material mass flow measured in the pneumatic conveying line (15) at the upstream location (1). A downstream flow control system controls the mass flow rate in the pneumatic conveying line (15) at the downstream location (2) by controlling the opening of a downstream flow control valve (51, 79i) responsive to the instantaneous mass flow rate sensed by a main downstream mass flow rate sensor (53).
摘要:
A device for continuously feeding a powdery solid out of a storage bin (10) and into a pneumatic conveying line (12, 12') comprises a first and a second intermediate vessel (14 and 16) that are placed adjacent to one another. The first intermediate vessel (14) is provided in the form of a sluice vessel having an upper sluice gate (18) and a lower sluice gate (20). The second intermediate vessel (16) is provided in the form of an injection vessel. A pneumatic intermediate conveyance (50) is placed between the lower sluice gate (20) of the first intermediate vessel (14) and an upper inlet (30) of the second intermediate vessel (16). This intermediate conveyance enables the powdery solid to be conveyed out of the first intermediate vessel (14) and into the second intermediate vessel (16).