Abstract: Provided is a ground flare in which a low-frequency vibration generated from a ground flare tower, such as a chimney, is properly adjusted to suppress it below a fixture-vibration generation limit, thereby preventing surrounding objects from resonating and vibrating. In a ground flare that burns a flammable exhaust gas with a burner at the lower end of a chimney, in which the lower end of the chimney and the periphery of the burner are surrounded by a windbreak, the low-frequency-noise sound pressure level of a ground flare tower composed of the chimney and the windbreak is reduced by selecting at least one of changing a natural frequency generated from the ground flare tower, using multiple ground flare towers, and installing a low-frequency-vibration absorber in the ground flare tower.

Abstract: The present invention provides a mercury removal system and method for effectively removing a mercury component, which is present in a gas stream in an extremely small amount in wet gas cleaning. The mercury removal system in wet gas cleaning includes a water washing tower for introducing therein a target gas containing a mercury component and transferring the mercury component into an absorbing solution, a flash drum (10) for flashing the absorbing solution discharged from the water washing tower to separate the absorbing solution into a gas component and waste water, an oxidation treatment means (1) for adding an oxidizing agent to the absorbing solution at the preceding stage of the flash drum, and a waste water treatment means for subjecting to coagulation sedimentation treatment the separated waste water containing the mercury component at the following stage of the flash drum to dispose of the mercury component as sludge.

Abstract: An object is to provide a gate valve capable of preventing operational deficiencies caused by particulate materials accumulating in a valve box, thus providing superior sealing properties and high durability, having a simple structure, and allowing inspection and maintenance to be performed easily.

Abstract: The present invention provides a mercury removal system and method for effectively removing a mercury component, which is present in a gas stream in an extremely small amount in wet gas cleaning used for coal or heavy oil gasification, petroleum refining and the like. The mercury removal system in wet gas cleaning comprises a water washing tower for introducing therein a target gas containing a mercury component and transferring the mercury component into an absorbing solution, a flush drum (10) for flushing the absorbing solution discharged from the water washing tower to separate the absorbing solution into a gas component and waste water, an oxidation treatment means (1) for adding an oxidizing agent to the absorbing solution at the preceding stage of the flush drum, and a waste water treatment means for subjecting to coagulation sedimentation treatment the separated waste water containing the mercury component at the following stage of the flush drum to dispose of the mercury component as sludge.

Abstract: An object is to provide a gate valve capable of preventing operational deficiencies caused by particulate materials accumulating in a valve box, thus providing superior sealing properties and high durability, having a simple structure, and allowing inspection and maintenance to be performed easily.

Abstract: It is an object to solve a bypass line corrosion problem effectively, enable prompt supply of a fuel gas into a bypass line in the event of an emergency, and provide an inexpensive coal gasification plant. An integrated coal gasification combined cycle power generation plant includes a coal gasification furnace, a dust remover, a gas refiner, a gas turbine and the like, a main system line connecting therebetween, and a bypass line connecting between the outlet side of the coal gasification furnace in the main system line and a flare stack, wherein a dust remover bypass valve which is disposed in an upstream portion of the bypass line and which opens and closes the bypass line, a treatment gas control valve which is disposed in a downstream portion of the bypass line and which controls the flow rate, and a first inert gas input line which is disposed downstream from the dust remover bypass valve and which supplies the inert gas to the bypass line are provided.