34 results about "Rectisol" patented technology

The invention relates to a process for removing an acid gas with a low-temperature methanol solution, solving the problem that a low-temperature rectisol plant enriches ammonia and has lower recovery rate of CO2, lower concentration of H2S in acid gases and large solution circulating volume in the traditional process. The process comprises feed gas preprocessing, desulfuration and decarbonization by an absorption tower, CO2 analysis and gas stripping and hydrogen sulfide concentration by a desorber, regeneration by a heat regenerator and deficient methanol separation by a methanol/water separation tower, wherein the feed gas is conveyed into an ammonia scrubber for deamination and preprocessing. The process can reduce the ammonia enrichment in the low-temperature rectisol plant, increase the recovery rate of CO2, improve the concentration of H2S in acid gases, reduce the circulating volume of the solution and ensure the quality of purified gas products.

An energy-saving one-step rectisol method belongs to the technical field of gas purification. The method is characterized in that two or three desulfuration segments of an absorption tower employ a sulfur-free semi-lean solution for absorption; intersegment coolers are adopted; the desulfuration segments can remove sulfide and approximately 50-60% of CO2 from virgin gas simultaneously; only one decarbonization segment of the absorption tower is adopted; a lean solution is used at the top of the tower, and the sulfur-free semi-lean solution is added; flash steam is absorbed by a sulfur-containing semi-lean solution in the medium-pressure flash evaporation process; after most of CO2 in the flash steam is absorbed, the solution is delivered to a lower tower of an H2S concentrating tower for gas stripping; a sulfur-free methanol solution gas stripping tower is additionally adopted and divided into one or two segments; solutions at the segments are heated appropriately before entering the tower; and the sulfur-free semi-lean solution is delivered to the absorption tower after the gas stripping. The energy-saving one-step rectisol method has the effects and benefits that the number of plates of the absorption tower is reduced by about 20%, the tower diameter is shortened, the circulation volume of a methanol lean solution is reduced, the regeneration load of a rich solution is also reduced, the energy consumption of a device is saved by about 30%, and the device investment is saved.

The invention provides a process for preparing substitute natural gas through sulphur-tolerant methanation of coal synthesis gas. The process is characterized in that the synthesis gas enters sulphur-tolerant methanation reactors I and II in sequence, and the mixed gas of the synthesis gas and water vapor enters a rectisol system so as to remove the impurities such as CO2, H2S and the like in the gas after undergoing sulphur-tolerant shift and sulphur-tolerant methanation reaction on a molybdenum-based bifunctional catalyst and then undergoes methanation reaction in methanation reactors I and II in sequence under the action of Ni-based methanation catalysts, thus obtaining the natural gas product. The process has the advantages of simple process flow, small equipment investment, low comprehensive energy consumption and excellent natural gas products.

According to a method disclosed in the invention for increasing yield of rectisol and/or liquid oxygen wash greatly and saving energy through pressure swing adsorption technique, the desulfurized gas or transformed gas is divided into two branches. One branch enters a pressure swing adsorption decarburization device for decarburization, and the other branch enters a low-temperature methanol carbon washing device for decarburization. The decarburized gas after decarburization of the voltage swing adsorption decarburization device enters a voltage swing adsorption hydrogen purification device for obtaining hydrogen product, and a hydrogen-nitrogen synthesis gas is obtained after allocating the nitrogen. The decarburized gas after decarburization of the voltage swing adsorption decarburization device enters a liquid hydrogen washing device, and the hydrogen-nitrogen synthesis gas is obtained after purification. After mixing the two branches of hydrogen-nitrogen synthesis gas and compressing the mixture in a synthesis gas compressor, the compressed gas enters an ammonia synthesis period. The invention also discloses a device for realizing the method. A yield increase amplitude which is higher than 50% can be realized according to the invention.

The invention discloses a low-temperature spiral wound heat exchanger for a non-converted gas cooler, and is mainly applied to the coal chemical industry fields of coal based syngas, coal-to-methanol, and the like, and the technical fields of the rectisol process comprising low-temperature gas purification and low-temperature liquefaction separation, and the like. The low-temperature spiral wound heat exchanger is tower spiral wound heat exchange equipment with the combination of single-fluid and double-fluid, achieving the purpose of precooling non-converted feed gas by process cold gas by mainly utilizing rectisol process off-gas and low-temperature syngas to precool the non-converted feed gas. According to the low-temperature spiral wound heat exchanger for the non-converted gas cooler, disclosed by the invention, the basic structure and the heat exchange process calculation method of a compound spiral wound heat exchanger combining a single-tube-bundle spiral wound heat exchanger and a double-tube-bundle spiral wound heat exchanger for the non-converted gas cooler are systematically researched, the method of introducing the moderate temperature cold source at the middle section and combining the single-fluid and double-fluid spiral wound heat exchangers up and down is adopted, and the entry points of multi-fluid heat exchange at different potential temperatures are improved, so that the heat exchange efficiency is enhanced, the heat exchange area is saved, and the size of the heat exchanger is reduced.

The invention discloses a measurement method for hydrogen sulfide content of a methanol solution and application of the measurement method. The measurement method comprises the following steps of constructing an absorbancy-hydrogen sulfide content standard curve; preparing a methanol solution to be measured into a sample to be measured; testing the sample to be measured through a spectrophotometer to obtain an absorbancy value of the sample to be measured; and obtaining a hydrogen sulfide content of the sample to be measured from the absorbancy-hydrogen sulfide content standard curve according to the measured absorbancy value. The hydrogen sulfide content of the methanol solution can be obtained by constructing the absorbancy-hydrogen sulfide content standard curve, preparing the methanol solution to be measured into the sample to be measured, measuring the absorbancy value of the sample to be measured and obtaining the result. The method is applied to liquid in actual production, so that the hydrogen sulfide content of a 'rectisol' solution can be measured accurately and conveniently, and therefore, the deficiency of the methanol solution can be determined, and the absorption capacity of the methanol solution in a purification process is guaranteed.

The invention discloses a Rectisol tail gas recovery system and method and their application and solves the problem that Rectisol tail gas treatment is high in cost. The technical process is simple, the main parameter is fan outlet pressure, and process parameters to be controlled are few and easy to adjust; Rectisol vented tail gas replaces seal nitrogen in a coal mill, the waste is utilized, resources are saved, and the investment in Rectisol tail gas treatment is lowered. According to the technical scheme, the Rectisol tail gas recovery system comprises a tail gas source, a separator, a fan and a coal mill, drops are removed from the tail gas source via the separator, the tail gas source is pressurized via a fan and is delivered to a sealed air passage in the coal mill so as to arrive at sealing, and the tail gas source is a Rectisol tail gas source.

The invention relates to a method for preparing liquefied natural gas from semi-coke tail gas. The method includes: firstly, after decoking and benzene and naphthalene removal of semi-coke tail gas, and sending to a rectisol unit for purification and desulfurization; then, mixing the desulfurized semi-coke tail gas with high-methane gas, jointly sending into a methanation unit for methanation to obtain a crude methane gas product, sending into the rectisol unit for purification and decarbonization; finally, performing cryogenic separation to remove nitrogen to obtain liquefied natural gas. Compared with the prior art, the method has advantages that by semi-coke tail gas treatment through the rectisol unit and the methanation unit, circulation absorbing agent consumption is sharply reduced,and energy consumption and system CH4 loss in a decarbonization process are reduced; in addition, by adoption of recovered CH4-rich gas and injection of water and/or system self-produced water vaporinto the methanation unit, methanation reaction temperature rise can be controlled so as to guarantee a methanation process against temperature runaway; moreover, heat balance of a whole system can beeffectively realized in the whole process, and economy in preparation of LNG (liquefied natural gas) from the semi-coke tail gas is improved.

The invention provides a low-temperature rectisol process, comprising the following steps: a) injecting methyl alcohol solution into untreated gases; b) cooling the untreated gases in which methyl alcohol solution is injected; and c) injecting the methyl alcohol solution into the cooled untreated gases again. The invention also provides a low-temperature rectisol device, comprising a second jet bubbler, a first heat exchanger and a first jet bubbler, wherein the second jet bubbler injects the methyl alcohol solution into the untreated gases, the first heat exchanger cools the untreated gases in which the methyl alcohol solution is injected, and the first jet bubbler injects the methyl alcohol solution into the cooled untreated gases again. The low-temperature rectisol process provided by the invention injects the methyl alcohol solution into the untreated gases before cooling to ensure that methyl alcohol is atomized and blended into gaseous phase, and the freezing point of the untreated gases is lowered; when cooling, moisture in the untreated gases has small possibility of condensing, so that the phenomenon that tube bundles are blocked in the heat exchanger can not appear, and gas output does not decrease.

Provided are an improved low-temperature rectisol method and an improved low-temperature rectisol device. Hydrogen sulfide and carbon dioxide in process gas are removed respectively in two absorbing towers, and the process gas is cooled between two towers so that part of carbon dioxide is liquefied and separated. The two towers absorb hydrogen sulfide and carbon dioxide respectively. Part of carbon dioxide is liquefied and separated by cooling the process gas after hydrogen sulfide is removed through the hydrogen sulfide absorbing tower so that content of carbon dioxide in the process gas is reduced, and content of carbon dioxide in the process gas entering the carbon dioxide absorbing tower is correspondingly reduced. The method can effectively reduce dimensions of a low-temperature rectisol pipeline and equipment, reduces methanol circulating quantity, equipment investment and production running costs are reduced, air-lift nitrogen dosage is reduced, and more pure-state carbon dioxide facilitating application and treatment is obtained.

The invention discloses a burner for a rectisol incinerator, and belongs to the field of burners. The technical problem to be solved is to provide the burner for the rectisol incinerator that the structure is simple, the control of fuel gas and other gas gases is independent, mixing is carried out after the gas enters the burner, potential safety hazards can be eliminated, gas does not cross, andthe safety coefficient is high. According to the technical scheme adopted for solving the technical problem, the burner for the rectisol incinerator comprises a furnace barrel, wherein a secondary fuel gas inlet pipe is arranged at the front part of the furnace barrel, a primary nozzle is arranged at the rear part of the furnace barrel, other gas inlet pipes are arranged between the primary nozzleand the secondary fuel gas inlet pipe, the outlet of the secondary fuel gas inlet pipe is divided into a plurality of nozzles which are annularly arranged, an annular wind shield is arranged at the outlet of each nozzle, and each annular wind shield is a conical wind shield. The burner for the rectisol incinerator can be widely applied to the field of burners.