摘要:
Gaseous effluents containing oxygen and no greater than 2% by volume of sulfur dioxide, SO.sub.2, for example those emanating from facilities for the industrial-scale production of sulfuric acid, are converted into useful solutions of ammonium or of alkali or alkaline earth metal bisulfites, by first absorbing such gaseous effluent in a solution of ammonium or of an alkali or alkaline earth metal sulfite and bisulfite, at a pH ranging from 5 to 7, and, secondly, contacting the solution thus produced with an acidic reagent, advantageously a gaseous feedstream containing oxygen and greater than 2% by volume of sulfur dioxide, the O.sub.2 / SO.sub.2 ratio by volume thereof being less than 5.
摘要翻译:含有氧气和不超过2体积%的二氧化硫的SO 2气体,例如从工业规模生产硫酸的设备中排出的SO 2,被转化为铵或碱金属或碱土金属的亚硫酸氢盐的有用溶液, 通过首先在pH为5至7的范围内吸收这种气态流出物在铵或碱土金属亚硫酸盐和亚硫酸氢盐的溶液中,其次,使由此产生的溶液与酸性试剂接触,有利地是气态进料流 含氧量大于2体积%的二氧化硫,其O 2 / SO 2的体积比小于5。
摘要:
A process of regeneration of scrubber bleed liquor discharged from SO.sub.2 gas scrubber in which there are provided two serially connected sludge blankets containing 15-40% finely divided solids in liquor overlain by a relatively clear supernatant liquor. The bleed liquor is introduced into the first blanket along with an aqueous slurry of ground limestone, liquor and limestone partially react in the first blanket then they are transferred to the second blanket for further reaction, after which the liquor is recycled to the scrubber and a proportional amount of reacted limestone is wasted. The liquor has a relatively short residence time in the system on the order of 30-180 minutes while solids residence in the system is on the order of 6 to 24 hours. A special embodiment is provided for use when the first sludge blanket is in a relatively small tank in which only a portion of the bleed liquor is supplied to the first sludge blanket and the balance is injected directly into the second sludge blanket.
摘要:
A flue gas dry scrubbing system achieves higher sulfur dioxide removal efficiency with a better utilization of alkali reagent chemicals as well as increased dry product recovery performance using a combination of spray drying with an alkali reagent slurry and with a recycled stream comprising a mixture of unreacted alkali, sulfite and sulfate reaction products and flyash which directly contacts the sulfur dioxide-containing flue gas. Preferably the recycled mixture contacts the flue gas in the spray dryer. The invention utilizes a splitting method and a splitter apparatus wherein the particle product powder is separated into two fractions for recycling and for product disposal. The rate of splitting is fully adjustable over a wide range.
摘要:
Fenton and Fenton-like system enhancing agent and the usage thereof are provided. It relates to a water treatment enhancer (enhancing agent) and the usage thereof. It widens water pH range of Fenton and Fenton-like system reaction. It reduces amount of Fe2+ required for Fenton reaction. It increases rate of Fenton-like reaction. The enhancing agent is selected from sodium sulfite, lithium sulfite, potassium sulfite, magnesium sulfite, calcium sulfite, hydroxylamine hydrochloride, hydroxylamine perchlorate, hydroxylamine sulfate, hydrazine, N,N-diethylhydroxylamine, amino ethanolamine, hydroxylamine solution or N,N,N′,N′-tetrasubstituted p-phenylenediamine. The method of use of enhancing agent comprises the steps of: adding Fenton or Fenton-like system enhancing agent, an agent for enhancement and hydrogen peroxide into water subject to treatment; and mixing and allowing reaction. The enhancing agent can increase the rate of reaction for the water treatment and reduce the dosage of the agent for enhancement.
摘要:
Processes for producing sodium bisulfite from sodium sulfite purge streams are disclosed which enable recovery of additional resource material including sodium bisulfite.
摘要:
A process for the simultaneous removal of sulfur dioxide and nitrogen oxides from a gaseous stream uses a sorbent containing magnesium ions and sulfite ions for sulfur dioxide removal and a metal chelating agent for nitrogen oxides removal, with the production of an amine disulfonate salt, such as potassium amine disulfonate, as a purified saleable by product.
摘要:
Geothermal steam is condensed with a sulfite solution to abate hydrogen sulfide. A portion of the hydrogen sulfide is converted in the condensation in the presence of soluble cationic polymeric catalysts to soluble sulfur compounds while avoiding elemental sulfur and carbonate formation. The remainder of the hydrogen sulfide is incinerated and the sulfur dioxide in the incinerator effluent is absorbed in an alkaline solution to form the sulfites for the geothermal steam condensation. By maintaining stoichiometric ratios, the hydrogen sulfide is substantially converted to soluble thiosulfate without the use of chelates, peroxides or makeup sulfites.
摘要:
Gas feed streams containing sulfur dioxide such as flue gas streams are first contacted with an aqueous solution of inorganic sulfites and bisulfites having a pH range from about 2 to about 6.5 to remove a minor amount of sulfur dioxide. The same gas stream is then contact with a second aqueous solution of sulfites and bisulfites having a pH range from about 7.0 to about 12.5. Alkali metal hydroxide or ammonium hydroxide solution is added to the liquid inlet of the second contactor and the solution of the second contactor is pumped to the liquid inlet of the first contactor.
摘要:
A process for the recovery of gypsum as a product of a dual alkali system for regeneration of a sodium base alkaline scrubber liquor in which the liquor reacts with ground limestone in two serially connected sludge blankets containing from 15%-40% solids in a liquor matrix and overlain by a relatively clear supernatant pool. Upon completion of regeneration the liquor is discharged from the second blanket to the scrubber cycle while a proportionate amount of the slurry is further treated to reduce its pH and/or increase its density and/or to displace regenerated scrubber from the matrix after which the slurry is transferred to a separate tank and there oxidized to gypsum then it is filtered. The filtrate is returned to the liquor regeneration cycle and the gypsum recovered as product.