39results about How to "Reduce recirculation air volume" patented technology

The invention discloses a technology for preparing liquefied natural gas and liquid ammonia by using coke oven gas. The coke oven gas is subjected to the steps of compression, purification, methanation, cryogenic separation and liquefaction of synthetic natural gas, variable pressure adsorptive separation and liquid ammonia preparation with hydrogen rich gas, so that the liquefied natural gas (LNG) of which methane purity is more than 99 percent and the liquid ammonia reaching national first level standard are obtained. By the technology, the hydrogen byproduct of the coke oven gas for preparing the LNG is fully utilized; effective ingredients of the coke oven gas such as H2, N2, CH4, CO and CO2 are furthest utilized; the CO and the CO2 are methanated, so that the yield of the CH4 is improved by about 1/3; the liquefied CH4 is used as the LNG and sold; and the rest nitrogen-containing hydrogen-rich gas is used as a raw material for synthesizing ammonia, so that the additional value of the coke oven gas is improved, and reliable raw material guarantee is provided for developing downstream products with high additional values and prolonging the product chain.

The invention belongs to the technical field of coke oven gas application, and particularly relates to a new process for synthesizing natural gas by methanation of coke oven gas. After the coke oven gas diluted by recycle gas passes through a methanation reactor bed, the coke oven gas and the recycle gas in a certain ratio enter a methanation reactor, the gas at the inlet of the methanation reactor of each stage consists of CO and CO2 which are less than 7 percent, the temperature of the inlet of the methanation reactor of each stage is controlled to be between 220 and 400 DEG C, and heat exchange is performed in the reactor of the last stage through a heat exchanger. The process can protect the environment and save energy; on technology, the methanation reaction process can sharply reduce the number of the heat exchangers and make full use of heat generated in the reaction; the process can well control the composition of the raw material gases entering the methanation reactor of each stage; and meanwhile, the process effectively controls the temperature of the gas at the outlet of the methanation reactor. The process is favorable for selection of reactor materials, reduces the quantity of the recycle gas, and reduces energy consumption so as to reduce the cost.

The invention discloses a circulating method for producing a natural gas by multi-stage methanation of semi-coke tail gas, and belongs to the field of preparation methods of natural gas. The preparation method comprises the following steps that: the purified semi-coke tail gas the hydrogen to carbon ratio of which is adjusted is used as a raw material, and the multi-stage methanation reaction is adopted to obtain a methane-rich gas; a front-end methanation part and a back-section methanation part are comprised, wherein the front-end methanation part is formed by connecting at least two methanation furnaces in series, and the back-section methanation part is formed by connecting more than one methanation furnace in series; and the obtained methane-rich gas is separated to obtain a product natural gas. The methanation process has strong controllability, the temperature of the methanation reaction can be controlled by adjusting the recycle gas, the raw material inlet temperature and the steam addition amount and other ways, and the temperature of the methanation reaction is controlled below 500 DEG C. The lower methanation operating temperature is not only favorable for performing the methanation reaction, reduces the requirements of the process on a material of a reactor and heat resistance of a catalyst, but also is favorable for prolonging the service life of the methanation reactor and the catalyst.

The invention belongs to the field of energy chemical industry, and discloses a methanation technique for preparing synthetic natural gas from coal-base synthetic gas, which comprises the following steps: synthetic gas, which is obtained by carrying out fine desulfurization on methane synthetic gas from a gas purification section, is divided into three fresh gas streams A, B and C; first-section inlet gas formed by mixing the fresh gas A and circulation gas enters a first section of a methane synthesis reactor, second-section inlet gas formed by mixing first-section outlet gas and fresh gas B enters a second section of the first methane synthesis reactor, and second-section outlet gas of the first methane synthesis reactor and fresh gas C are mixed and enter a second methane synthesis reactor; after outlet gas of the second methane synthesis reactor is cooled, part of gas enters a circulating compressor to be pressurized and returns to the inlet of the first section of the first methane synthesis reactor as circulating gas, and the rest of gas sequentially enters a third methane synthesis reactor and a fourth methane synthesis reactor to be subjected to methane synthetic reaction; and outlet gas of the fourth methane synthesis reactor, in which the methane content is higher than 94% on dry basis, is cooled and dehydrated to obtain satisfactory synthetic natural gas SNG.

The invention relates to a method of producing substitute natural gas by methanation of synthesis gas, mainly solving problems, namely large using amount of recycle gas, high energy consumption of compressors, and excess of the H2 component or the CO2 component in substitute natural gas products, of high-temperature methanation reactions in the prior art. According to the technical scheme adopted by the method, the method comprises: a) a step of providing a high-temperature methanation reaction zone including n-stage series-connected reactors; b) a step of dividing the synthesis gas raw materials into n sections and respectively feeding the n sections of the synthesis gas raw materials into inlets of the reactors at all stages in the high-temperature methanation reaction zone, wherein the stream Vn flowing out from the reactor at the final stage is divided into Vn' and Vn'' and the stream Vn' is condensed and circulated to the inlet of the reactor at the first stage; c) a step of providing a low-temperature methanation reaction zone including m-stage series-connected reactors; and d) a step of supplementing a stream I containing CO2 to a reactor at any stage in the low-temperature methanation reaction zone, and a substitute natural gas product is obtained after the reaction. By the technical scheme, the problems are solved well and the method can be used in industrial production of the substitute natural gas from the synthesis gas.

The invention relates to a method of producing substitute natural gas from synthesis gas, mainly solving problems, namely large using amount of recycle gas, high energy consumption of compressors and short service lifetime of catalysts, of high-temperature methanation reactions in the prior art. According to the technical scheme adopted by the method, the method comprises: a) a step of providing a high-temperature methanation reaction zone including n-stage series-connected reactors, wherein the n is not less than 2, each reactor is divided into m sections of catalyst layers and the m is not less than 2; b) a step of dividing the synthesis gas raw materials into n sections and respectively feeding the n sections of the synthesis gas raw materials into inlets of the reactors at all stages in the high-temperature methanation reaction zone, wherein each section of the synthesis gas raw materials that enters a reactor is then divided into m streams and the m streams respectively enter the corresponding catalyst layers; c) a step of allowing a stream flowing out of an outlet of each of the reactors except the reactor at the final stage to enter the first section of catalyst layer in the reactor at the next stage; and d) a step of shunting the stream Vn flowing out from the reactor at the final stage to obtain a part Vn', and circulating the stream Vn' after the Vn' is condensed to the inlet of the reactor at the first stage. By the technical scheme, the problems are solved well and the method can be used in industrial production of substitute natural gas from synthesis gas.

The invention relates to a method for producing substitute natural gas. The problems of large using amount of high-temperature methanation reaction circulating gas, high energy consumption of a compressor and excess of an H2 or CO2 component in a substitute natural gas product in the prior art are mainly solved. According to the technical scheme, the method comprises the following steps: (a) proving a high-temperature methanation reaction area, wherein the high-temperature methanation reaction area comprises an n stages of cascaded reactors; (b) dividing synthesis gas raw materials into n sections, causing the n sections of synthesis gas raw materials to enter an inlet of a reactor in each stage in the high-temperature methanation reaction area, dividing a material flow Vn flowing out of an outlet of the reactor in a final stage into Vn' and Vn', and compressing and circulating the material flow Vn to an inlet of the reactor in the first stage; (c) providing a low-temperature methanation reaction area, wherein the low-temperature methanation reaction area comprises m stages of reactors which are connected in series; (d) supplementing an H2-containing material flow I into the reactor in any stage of a low-temperature methanation unit, and performing reaction to obtain the substitute natural gas product. According to the method, the problems are well solved; the method can be used for industrial production of preparing the substitute natural gas with synthesis gas.

The invention relates to a method for preparing substitutive natural gas by synthesis gas methanation. The method mainly solves the problems that the consumption of high-temperature methanation reaction recycle gas is great and the energy consumption of a compressor is high in the prior art. The method comprises the following steps that a) a high-temperature methanation reaction area is provided; the high-temperature methanation reaction area comprises n reactors connected in series, wherein n is greater than or equal to 2; b) raw synthesis gas containing H2, CO, CO2 and H20 is divided into n sections to enter inlets of the reactors in the high-temperature methanation reaction area respectively; flows flowing out of outlets of the reactors except the last reactor flow into inlets of the next reactors respectively; a flow Vn flowing out of an outlet of the last reactor is divided into Vn' and Vn''; the flow Vn' is compressed and then circulates to the inlet of the first reactor; c) a low-temperature methanation reaction area is provided; the low-temperature methanation reaction area comprises m reactors connected in series, wherein m is greater than or equal to 2; and d) the flow Vn'' enters the low-temperature methanation reaction area to react; and then the substitutive natural gas is obtained. With the adoption of the technical scheme, the problems are solved better, so that the method can be used in industrial production of substitutive natural gas preparation by the synthesis gas.

A methanation technology or preparing SNG from coal-based synthetic gas comprises the following steps: methane synthetic gas from a coal gas purifying workshop section is finely desulphurized, and the desulphurized synthetic gas is divided into four virgin gases A, B, C and D; the virgin gas A and circulation gas simultaneously enter the first segment of a first methane synthesis reactor, first segment outlet gas and the virgin gas B simultaneously enter the second segment of the first methane synthesis reactor, the outlet gas of the second segment of the first methane synthesis reactor and the virgin gas C simultaneously enter the first segment of a second methane synthesis reactor, the outlet gas of the first segment of the second methane synthesis reactor and the virgin gas B are mixed to form second segment gas, and the second segment gas enters the second segment of the second methane synthesis reactor; and the outlet gas of the second methane synthesis reactor is cooled, parts of the cooled gas is pressurized without water separation, the pressurized gas returns to the inlet of the first segment of the first methane synthesis reactor as circulation gas, the remaining gas sequentially enters a third methane synthesis reactor and a fourth methane synthesis reactor and undergoes a methane synthesis reaction, the methane dry base content of the outlet gas of the fourth methane synthesis reactor is greater than 95%, and the outlet gas of the fourth methane synthesis reactor is cooled and dehydrated to obtain the SNG.

The invention discloses a method for low H ₂ /N ₂ A method for producing synthetic ammonia from synthetic gas, comprising: Step 1: converting H below the stoichiometric ratio ₂ -N ₂ The synthesis gas is mixed with the circulating synthesis gas, pressurized by the compressor and preheated by the heat exchanger; step 2: the preheated mixed gas in step 1 first passes through an iron-based catalyst synthesis ammonia reactor, so that the outlet ammonia concentration reaches or exceeds 10 %, mixed gas H ₂ /N ₂ The ratio drops to or lower than 2.8; step 3: the mixed gas in step 2 passes through four alternately arranged heat exchangers and ruthenium-based catalyst synthesis ammonia reactors in turn, and the final outlet ammonia concentration reaches more than 25%; H ₂ /N ₂ The ratio is 1.00 to 2.50. This structure is beneficial to control the temperature of the catalyst bed, to ensure that the catalyst does not overheat, and to exert the high activity of the ruthenium-based catalyst under relatively low temperature and low pressure conditions, while maintaining the structure and stability of the ruthenium-based ammonia synthesis catalyst. Effectively improve the final outlet ammonia concentration of synthetic ammonia under the premise of high efficiency, which can reach more than 25%.

The invention discloses a reaction device for preparing mixed aromatics from methanol. The reaction device comprises a methanol evaporator, a reactor body, a compressor, a gas heat exchanger and a gas-liquid separator, wherein the methanol evaporator is connected to the reactor body through a pipeline; the reactor body is connected to an inlet of the gas heat exchanger through a pipeline; an outlet of the gas heat exchanger is connected to an inlet of the gas-liquid separator through a pipeline; an outlet of the gas-liquid separator is connected to an inlet of the compressor; an outlet of the compressor is connected to the methanol evaporator; a heating unit is arranged in the reactor body and is a heat pipe type heat exchanger. According to the reaction device, the structure is simple, the cost is lowered, and the heat energy is recovered; the low-power compressor is adopted for bringing out heat in the reactor body, so that the electrical energy is saved and the service life of the compressor is prolonged.

The invention discloses a two-stage double-separation methanol production method which comprises the following steps of: (1) compressing a second mixed gas containing a second complementary gas and asecond lean gas by a circulator, feeding the compressed second mixed gas into a first reactor for reaction, and discharging a first tower outlet gas; (2) recovering methanol from the first tower outlet gas to form a first lean gas; (3) mixing the first lean gas and the first complementary gas to form a first mixed gas, enabling the first mixed gas to enter a second reactor for reaction, and discharging a second tower outlet gas; and (4) recovering methanol from the second tower outlet gas to form a second lean gas, heating the second mixed gas by the first tower outlet gas through a first heatexchanger, and heating the first mixed gas by the second tower outlet gas through a second heat exchanger. In the application, the material circularly flows between the two reactors, so that the volume ratio of the first complementary gas to the second complementary gas is approximately the same, the reaction parameters of the two reactors are also approximately the same, the reaction of the tworeactors can be controlled in the same manner, and the production stability is improved.