摘要:
A solution or slurry containing a carbonate or sulfite, or both is continuously supplied into a tightly closed vessel, while any excess of the liquid is allowed to overflow the vessel. Sulfuric acid is supplied into the vessel to maintain the pH level of the liquid in the vessel at a value not exceeding 3. Air is supplied into the vessel as a carrier gas for CO.sub.2 or SO.sub.2 or both formed by the reaction of the carbonate or sulfite or both in the liquid with the sulfuric acid. The carrier gas is collected from the vessel, and the concentration of CO.sub.2 or SO.sub.2 or both in the carrier gas is determined. The concentration of the carbonate or sulfite or both in the liquid is obtained by calculations from the concentration of CO.sub.2 or SO.sub.2 or both, the flow rate of the liquid and the flow rate of the carrier gas.
摘要:
A process for desulfurizing an exhaust gas which comprises desulfurizing an exhaust gas containing SO.sub.2 by bringing it into contact with a slurry containing calcium compounds and aluminum compounds, characterized in that the concentration of the dissolved aluminum ion in said slurry is detected and a manganese compound is supplied into said slurry in such a manner that the ratio of the concentration of manganese (including both solid and liquid) to said concentration of the dissolved aluminum ion may be maintained in a molar ratio of less than 1 in said slurry.
摘要:
Five combustion exhaust gas treatment systems capable of removing dust and selenium (Se) in combustion exhaust gas and making harmless are proposed: (1) combustion exhaust gas is cooled to 350° C. or less, dust is separated, Se is transformed into insoluble compound, and Se is separated; (2) combustion exhaust gas is cooled to 350° C. or less, dust is separated, Se elution preventive agent is added, and dust is formed into scale; (3) dust in combustion exhaust gas is collected by dust collector, dust is formed into slurry by making use of part of circulation liquid in desulfurization apparatus, and tetravalent Se in dust slurry is transformed into insoluble compound, which is separated into solid and liquid; (4) dust is separated from combustion exhaust gas by dust collector, and it is heated to gasify Se, and is led into desulfurization apparatus, etc., and formed into slurry, and Se is made into insoluble compound; and (5) a treating agent for making tetravalent Se insoluble is added to part of circulation liquid in desulfurization apparatus, and it is sprayed into combustion exhaust gas to make Se insoluble.
摘要:
The present invention provides a mercury removal method which can effectively remove very small amounts of mercury components present in a gas during wet gas purification such as coal or heavy oil gasification gas purification and petroleum refining. A mercury removal method for the removal of mercury present in a gas, the method comprising the steps of bringing a gas containing at least mercury and not less than 10 ppm of hydrogen sulfide into gas-liquid contact with an absorbing fluid under pressurized conditions so as to cause mercury to pass into the absorbing fluid; flashing the mercury-containing absorbing fluid under lower-pressure conditions to separate it into gaseous components and liquid components; and removing the mercury contained in the separated gaseous components by adsorption to an adsorbent.
摘要:
A liquid extracting apparatus in accordance with the present invention is configured so that a connection pipe 22a (suction-side pipe) of a pump 22 for extracting slurry liquid content is connected to the upper end side of a liquid content introduction path to which slurry in a tank 8 can be introduced to attain the precipitation and separation of solid content, and a number of tubes 26 are packed at the lower end portion of the liquid content introduction path 21. The present invention can provide a simple liquid extracting apparatus that can effectively extract only liquid content in the slurry (suspension) moving in the tank.
摘要:
This invention is related to a wet gas process which would not require a spray pump, and which would allow the absorption liquid to be recovered smoothly even if the flow velocity of the gases entrained to the liquid should decrease. A wet gas processing apparatus in which the absorption liquid collected in the first liquid storage tank is sprayed in a specified direction (which may be upward, horizontal or downward) by a discharge unit consisting of spray nozzles (14) or the like in the absorption tower. The sprayed liquid is brought into contact with the exhaust gases which are conducted into the tower, and the targeted components of the gases are absorbed and removed. This processing apparatus is distinguished by the following. The first liquid storage tank for the absorption liquid comprises a pressure tank (11) which generates a pressurized gas in the space above the surface of the collected liquid (11a). The increased pressure of the pressurized gas is employed to spray the liquid collected in the pressurized tank from the spray nozzle unit in the absorption tower. This apparatus is further distinguished as the following. This invention has overflow ports which generate a virtually horizontal overflow or source flow. The absorption liquid propelled by the overflow ports makes orthogonal contact with the flow of exhaust gases, which results in both atomization of the liquid and liquid-vapor contact.
摘要:
This invention relates to a gasification power generation process wherein a product gas A1 obtained by the gasification of coal or petroleum is used as the fuel of a gas turbine 4 for electric power generation, the process comprising the steps of dedusting product gas A1, introducing product gas A1 directly into gas turbine 4 as the fuel thereof to effect electric power generation, and subjecting the exhaust gas A2 discharged from gas turbine 4 to a gas purification treatment including at least desulfurization. This invention can provide a gasification power generation process which is more suitable for practical use from an economic point of view in that a high degree of exhaust gas purification and a marked improvement in thermal efficiency can be achieved and, moreover, the construction of the equipment for carrying out a gas purification treatment including desulfurization can be highly simplified.
摘要:
This invention relates to a wet flue gas desulfurization apparatus including: an absorption tower having defined in the lower part thereof a tank for holding a calcium compound-containing slurry fed thereto; a circulating pump for delivering the slurry within the tank to the upper part of the absorption tower in order to bring it into contact with flue gas; air supply member for supplying air to the tank for purposes of oxidation; a withdrawal pump for withdrawing the slurry within the tank in order to recover gypsum formed as a by-product or discharge waste water; falling slurry withdrawal member for withdrawing part of the slurry delivered to the upper part of the absorption tower by the circulating pump and falling through the absorption tower at a position above the liquid surface of the tank; and mixing member for the slurry withdrawn by the falling slurry withdrawal member with the slurry withdrawn from the tank by the withdrawal pump, whereby oxidizing substances produced in the tank of the absorption tower can be decreased by reduction.
摘要:
In a flue gas desulfurization process wherein, when sulfur oxide-containing exhaust gas is treated with an absorbing solution containing a calcium compound, an oxygen-containing gas is passed through the absorbing solution and the flow rate of the oxygen-containing gas is controlled by detecting the oxidation-reduction potential of the absorbing solution continuously, an oxidation controlling method which comprises detecting a first deviation signal between the oxidation-reduction potential of the absorbing solution and the oxidation-reduction potential of the absorbing solution in a completely oxidized state and controlling the flow rate of the oxygen-containing gas in response to a second deviation signal between the first deviation signal and a preset oxidation-reduction potential deviation value.
摘要:
A method for desulfurizing an exhaust gas containing SO.sub.2 and NO.sub.x in accordance with a wet lime process, the aforesaid desulfurizing method being characterized by comprising the steps of drawing a part of an absorbing slurry, subjecting a filtrate obtained by the solid-liquid separation of the drawn absorbing slurry to an electrolysis treatment in the presence of chlorine ions, or after adjusting the filtrate to pH 3-4, mixing a hydrochlorite with the filtrate, and then refeeding the filtrate as a make-up water to an absorbing tower.