摘要:
A method for the wet treatment of combustion exhaust gases comprising SO.sub.2 and HCl, the method comprising detecting an amount of HCl in the exhaust gas and feeding, to an exhaust gas treating tower, a sodium salt in an amount corresponding to at least the detected amount of HCl so that all the HCl is able to be converted into NaCl in the exhaust gas treating tower, along with CaCO.sub.3 or Ca(OH).sub.2 used as an SO.sub.2 absorbent.
摘要:
The present invention relates to a process for wet-treating an exhaust gas which comprises simultaneously removing a nitrogen oxide (NO.sub.x) and a sulfur oxide (SO.sub.x) from an exhaust gas containing these oxides by treating exhaust gas containing oxides of nitrogen and sulfur with a lime or limestone slurry containing alkali metal or alkaline earth metal iodide.
摘要:
A gas refining method for adsorbing a reducing gas obtained by pressure gasification of coal or oil comprises introducing a reducing gas stream into an adsorbing and removing zone where it contacts an adsorbent. Sulfur-containing compounds are adsorbed onto the adsorbent and a first oxygen-containing gas stream is introduced into the adsorbing and removing zone in order to form a regeneration gas containing sulfur dioxide. The regeneration gas is contacted with a second oxygen-containing stream and a calcium-containing liquid slurry to effect absorption of sulfur dioxide by the slurry and precipitation of a gypsum compound. The temperature of the slurry is varied to cause selective precipitation of 60 -gypsum hemihydrate or gypsum dihydrate.
摘要:
A gas refining system for adsorbing a reducing gas includes a reduced gas stream, a section for adsorbing and removing sulfur-containing compounds in the reducing gas, an adsorbent which contacts the reduced gas stream, an oxygen-gas containing stream which enters the adsorbing and removing section, a calcium-compound containing stream, and a reactor which receives the above streams and allows for the adsorption of sulfur dioxide and precipitation of a gypsum compound.
摘要:
A method of producing solid molding products from a slurry which has undergone absorption in wet-limestone gypsum desulfurization of flue gas includes the steps of concentrating the gypsum-containing absorption slurry, mixing and kneading the solid concentrated slurry with flyash and quicklime or slaked lime, molding the mixture into a given shape using a mold and then curing a resulting molding product in a reaction chamber wherein a part of desulfurized gas is passed. The method also includes solidifying a molded product by drying with water-saturated hot air produced with heat recovered from the flue gas and with water added into a heat recovery process.
摘要:
This invention relates to a gas refining system wherein a high-temperature and high-pressure reducing gas is introduced into a fixed-bed desulfurizer packed with an adsorbent by which sulfur compounds contained in the high-temperature and high-pressure reducing gas are adsorbed and removed in the form of a sulfide, and the adsorbent having the sulfide adsorbed thereon is regenerated by roasting it with a regenerating gas containing oxygen, characterized in that the gas refining system is equipped with oxygen concentration control means for controlling the oxygen concentration in the regenerating gas introduced into the desulfurizer so as to keep the internal temperature of the desulfurizer during the regeneration reaction within the allowable temperature range of the adsorbent. This invention includes an embodiment in which the exhaust gas obtained after the regeneration reaction gas is brought into contact with a calcium compound-containing slurry to recover gypsum is recycled to the desulfurizer for use as the regenerating gas for the adsorbent. Thus, the adverse effect of the heat of regeneration reaction on the adsorbent used in the fixed-bed desulfurizer can be avoided positively and easily.
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:
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.
摘要:
A wet-type exhaust gas desulfurization system comprises a reservoir for trapping an absorbing solution which has absorbed SO.sub.2 from exhaust gas; an absorbing solution circulating tank disposed directly under the reservoir; a plurality of bottom pipes which are installed at the bottom of reservoir and extend downward into the absorbing solution in the circulating tank and whose lower end is open, or drop pipes which depend into the absorbing solution and whose lower ends are open; and air supply pipe at least one end of which is open to the atmosphere; a pipe for discharging the air above the surface of absorbing solution onto the surface of solution in the reservoir; and a pipe for supplying the absorbing solution in the circulating tank to a spray nozzle at the upper part of the absorbing tower.
摘要:
A flue gas desulfurization process for treating flue gases containing SO.sub.2, NO.sub.x, and halogen gases by the wet lime method, in which part of the absorbent liquid is extracted, freed from iodine, and recycled as makeup water to the absorption column.