摘要:
The metal surface protected against metal-dusting corrosion has an insulating layer of a gas-permeable, thermally insulating material. The side of the thermal insulating layer that is colder during operation is in direct vicinity of the metal surface, and the side of the insulating layer that is hotter during operation is heated by a gas stream containing carbon monoxide, which in addition contains hydrogen and/or steam and has a temperature in the range from 300 to 1700.degree. C. In the region between the metal surface to be protected and the hot side of the insulating layer a catalyst is provided for reacting carbon monoxide with hydrogen and/or steam.
摘要:
The process for dry desulfuration of a combustion gas includes providing an electrostatic precipitator (12) or an inertia force separator for dedusting; dedusting the combustion gas at temperatures of 100.degree. C. to 180.degree. C. in the electrostatic precipitator or at temperatures of 100.degree. C. to 700.degree. C. in the inertia force separator to form a partially dedusted combustion gas with a solids content of 5 to 40 g/Nm.sup.3 ; mixing the partially dedusted combustion gas with CaO and/or Ca(OH).sub.2 and optionally CaCO.sub.3 to form a gaseous mixture; providing a circulating fluidized bed device including a fluidized-bed reactor (8) and a downstream solids separator (7) with a return line (17) to the fluidized-bed reactor (8), the solids separator (7) being either another electrostatic precipitator or a bag filter; feeding the gaseous mixture and water into the fluidized-bed reactor (8); cooling the gaseous mixture in the fluidized-bed reactor (8) to a temperature of 50.degree. C. to 90.degree. C.; withdrawing a solids-containing gas from an upper portion of the fluidized-bed reactor (8); feeding the solids-containing gas into the solids separator (7) to form separated solids and a cleaned gas; recycling one portion of the separated solids into the fluidized-bed reactor (8) and mixing another portion of the separated solids with the combustion gas.
摘要:
A water-based adhesive is disclosed which contains an aqueous dispersion of one or more phenol resins stabilized by one or more polyacrylates, one or more latexes with one or more halogenated polyolefins and one or more cross-linking agents. The invention also includes a method of priming a substrate in which the substrate is coated with the adhesive as a primer and then with a cover cement and finally bonded to rubber under vulcanization.
摘要:
Methanol is catalytically produced from a synthesis gas containing hydrogen and carbon oxides on copper-containing catalysts at pressures in the range from 20 to 120 bar and temperatures in the range from 130.degree. to 350.degree. C. The synthesis gas is first of all passed through a first synthesis reactor, in which the catalyst is provided in tubes surrounded by water as a coolant which is boiling at an elevated pressure. From the first reactor a first mixture containing gases and methanol vapor is withdrawn and passed through a second synthesis reactor. In the second reactor the catalyst is cooled with synthesis gas.
摘要:
The ore which contains gold and at least one of the metals silver, copper, nickel, zinc or iron is calcined at temperatures in the range from 500.degree. to 900.degree. C. with the addition of oxygen-containing gas, thereby producing a metal-oxide-containing solids mixture and a SO.sub.2 -containing exhaust gas. The SO.sub.2 containing exhaust gas is brought in contact with aqueous solution, thereby producing a sulfite-containing solution. The solids mixture from the calcination is cooled to temperatures in the range from 50.degree. to 300.degree. C. and is stirred up with the sulfite-containing solution. Metal oxides are dissolved, and a sulfate-containing solution os formed. In a first separating zone, the sulfate-containing solution is separated from the solids, and either the solids are supplied to a gold leaching or the sulfate-containing solution is subjected to a further treatment for the separation of nonferrous metals.
摘要:
The process forms a phosphate coating on a steel strip or sheet having a galvanized or alloy galvanized side and a steel side so that the phosphate coating is only present on the galvanized or alloy galvanized side. This process includes contacting the galvanized or alloy galvanized side of the steel strip or sheet with a phosphatizing solution for 4 to 20 seconds at a temperature of from 45.degree. C. to 80.degree. C. The phosphatizing solution has an S value of from 0.08 to 0.30 and contains 0.5 to 5 g/l zinc, 3 to 20 g/l P.sub.2 O.sub.5, 0.020 to 0.2 g/l nitrite, 3 to 30 g/l nitrate and 0.2 to 2.5 g/l complexing agent for iron. Chelate forming substances, such as tartaric acid, citric acid, ethylenediamine-tetraacetic acid, nitrilotriacetic acid and/or oxalic acid, may be used as the complexing agent for iron. The phosphatizing solutions may also contain other bivalent cations, particularly manganese and/or nickel cations.
摘要:
The process for separating toxic organic substances from a dust-containing exhaust gas from a sintering process, particularly a process of sintering iron ore, includes bringing the entire exhaust gas from a sintering conveyor into contact with clays, layer silicate, and diatomaceous earth or mixtures thereof within a gas-solids suspension for a reaction time of from 0.5 to 10 seconds above the dew point at a temperature from 90.degree. to 180.degree. C. and at a velocity from 6 to 200 meters per second. The median particle diameter, d.sub.50, of the solid adsorption agent in the gas-solids suspension is from 5 to 100 micrometers and the mean suspension density of the gas-solids suspension is from 5 to 500 g solids per sm.sup.3 exhaust gas. The dust and other solids are subsequently jointly separated from the gas-solids suspension, and part of the separated solids is again contacted with the exhaust gas from the sintering conveyor. An apparatus for carrying out the process is also described.
摘要:
The biomass, particularly lump wood, is supplied to a shaft reactor at its top and is initially preheated to temperatures of about 150.degree. to 280.degree. C. and dried by a counterflowing hot gas. This is followed by a treatment in an underlying carbonizing zone, the upper portion of which is supplied with hot purging gas at a temperature of 250.degree. to 600.degree. C. The hot purging gas flows downwardly through the carbonizing zone co-currently with the wood. A gas mixture which contains purging gas and gas produced by carbonization is withdrawn from the lower portion of the carbonizing zone and is at least in part combusted outside the shaft reactor to produce a combustion gas, which is used at least in part as hot purging gas.
摘要:
The process purifies exhaust gas produced by combustion of waste materials including garbage, industrial wastes and/or sewage sludge. The exhaust gas is contaminated particularly with dust, SO.sub.2, HCl, HF, Hg, mercury compounds, and dioxins and furans and can be expected to have an oxygen content. In the process, the exhaust gas is treated in a spray absorber with a suspension of Ca(OH).sub.2 ; the exhaust gas is subsequently filtered in two successive filteration stages; the exhaust gas leaving the first filtering stage still has an SO.sub.2 content of from 20 to 500 mg/sm.sup.3 ; activated carbon, preferably hearth furnace coke, is introduced into the exhaust gas stream before the second filtering stage; and the exhaust gas is finally scrubbed with a mixture which contains water and NaOH, Na.sub.2 CO.sub.3, Ca(OH).sub.2 and CaCO.sub.3 in a dissolved or suspended state.
摘要翻译:该过程净化了废物(包括垃圾,工业废物和/或污水污泥)燃烧产生的废气。 废气特别被粉尘,SO2,HCl,HF,Hg,汞化合物,二恶英和呋喃污染,并且可以预期具有氧含量。 在该过程中,废气在具有Ca(OH)2的悬浮液的喷雾吸收器中处理; 废气随后在两个连续的过滤阶段中过滤; 离开第一过滤阶段的废气仍然具有20至500mg / sm 3的SO 2含量; 在第二过滤阶段之前将活性炭,优选炉床焦炭引入废气流中; 并且最终用含有水和NaOH,Na 2 CO 3,Ca(OH)2和CaCO 3的溶解或悬浮状态的混合物洗涤废气。
摘要:
The tubular heater comprises numerous tubes, which are disposed in a combustion chamber and contain catalyst. A synthesis gas, which mainly comprises hydrogen, carbon monoxide, and carbon dioxide, is prepared in the tubes. There is a risk of a formation of carbides (metal dusting corrosion) on the outside surface of the outlet ends of the tubes. To prevent such corrosion, a gaseous or vaporous protecting fluid, which is substantially free of CO, is supplied to the region surrounding the outlet ends of the tubes.