SE176549C1

SE176549C1 -

Info

Publication number: SE176549C1
Authority: SE
Publication date: 1961-01-01

Description

Uppfinnare: GFauser Prioritet begard frem den 18 mars 1954 (Italien) Det är kant att for att vid vissa exotermiska hogtrycksreaktioner vid hog temperatur, exempelvis vid ammoniaksyntesen och vid metanolsyntesen, erhalla ett Mgt syntesutbyte maste katalysatorns temperatur lianas inom bestamda granser. Det är ador advandigt, att det genom reaktionen utvecklade varmet avlagsnas omsorgsfullt, sa snart det frigores. For att astadkomma delta har det redan foreslagits att uppdela katalysatormassan i olika skikt och att i de olika mellanskikten inbygga spiralror av icke rostande stal, i vilka vatten pumpas. Reaktionsvarmet kan pa sa satt utnyttjas till angalstring. Inventor: GFauser Priority requested March 18, 1954 (Italy) In order to obtain a high synthesis yield in certain exothermic high pressure reactions at high temperature, for example in ammonia synthesis and in methanol synthesis, the catalyst temperature must be within certain limits. It is adorable that the heat generated by the reaction is carefully removed as soon as it is released. In order to achieve participation, it has already been proposed to divide the catalyst mass into different layers and to incorporate in the various intermediate layers spiral tubes of non-rusting steel, in which water is pumped. The heat of reaction can thus be used for angulation.

Konstruktionen av kylslingorna, vilka anbringas i synteskolonnen och vid driften skola utsattas for ett tryck av flera hundra atmosfarer och temperaturer, som kunna uppga till 600° C, erbjuder emellertid stora svarigheter. Vid dessa temperaturer sjunker narnligen std.- lets motstandiskraft vasentligt, och aven om specials-M.1 med hog krom- och nickelhalt anvandes, maste anda ror med mycket stor vaggtjocklek komma till anvfindning. DarfOr ar det praktiskt omOjligt att konstruera sadana apparater, ndr driftstrycken overstiga 350– - 400 atmosfarer. Foreliggande uppfinning erbjuder en rationell l5sning for overvinnande av de ovannamnda svarigheterna. Den Or det mojligt att nedbringa vaggtjockleken hos valtencirkulationsroren for bortfOring av reaktionsvarmet till ett minimum, aven nar forf arandet genomfores vid tryck av 800-1000 atmosfarer. However, the construction of the cooling coils, which are placed in the synthesis column and during operation are subjected to a pressure of several hundred atmospheres and temperatures, which can reach 600 ° C, offer great similarities. At these temperatures, the resistance force of the standard decreases significantly, and although special M.1s with a high chromium and nickel content were used, spirits with very large rock thickness must be used. Therefore, it is practically impossible to design such devices when the operating pressures exceed 350–400 atmospheres. The present invention offers a rational solution for overcoming the above-mentioned responsibilities. It is possible to reduce the rock thickness of the valent circulation tubes to remove the heat of reaction to a minimum, even when the process is carried out at a pressure of 800-1000 atmospheres.

Huvudpatentet 149 378 avser ett forfarande av ovan angivet slag, vid vilket reaktionsvarmet bortfores darigenom, att vatten bringas i cirkulation i varmevaxlare, vilka aro anordnade pa olika hojd ikatalysugneu, varvid trycket i varmevaxlarna halles praktiskt taget lika rued det, som racier i syntesrummet, darigenom att kretsloppet for de fOr syntesen avsedda komprimerade gaserna star i forbindelse med kretsloppet for det for avledning av reaktionsvarmet avsedda vattnet Over en pa lampligt satt kyld samlingsbehallare pa sadant salt, att vattenanga hindras fran att intranga i .synteskretsloppet. The main patent 149 378 relates to a process of the above kind, in which the heat of reaction is removed by circulating water in heat exchangers, which are arranged at different heights in the catalytic converter, whereby the pressure in the heat exchangers is kept practically as rough as that in the synthesis room, thereby that the circulation of the compressed gases intended for synthesis is in connection with the circulation of the water intended for dissipation of the heat of reaction.

Enligt foreliggande uppfinning astadkommes kylningen av katalysatormassan genom cirkulation av vatten enligt termosifonprincipen. Forfarandet enligt fOreliggande uppfinning kannetecknas d:arav, att reaktionsvarmet bortledes medels i katalyskammaren anordnade varmevaxlare, i vilka vatten under tryck cirkulerar enligt termosifonprincipen och avgiver varmet till en ovanfor anordnad angpanna, varvid expansionskarlet for det enligt termosifonprincipen cirkulerande vattnet halles vidtemperatur under vatt- nets kritiska temperatur och star i fi3rbindelse med synteskretsloppet. According to the present invention, the cooling of the catalyst mass is effected by circulating water according to the thermosiphon principle. The process according to the present invention can be characterized in that the reaction heat is dissipated by means of heat exchangers arranged in the catalytic chamber, in which water under pressure circulates according to the thermosiphon principle and gives off the heat to an above-arranged steam boiler, the expansion vessel temperature and star in connection with the synthesis circuit.

Pa den bifogade ritningen visas ett utforingsexempel enligt uppfinningen tillampat pa ammoniaksynte s en. The accompanying drawing shows an exemplary embodiment according to the invention applied to ammonia synthesis.

Den frail en hogtryckskompressor M kommande blandningen av kvave och vate, som befinner sig under Mgt tryck, genomstrommar varmevaxlaren D, som Or anordnad i synteskolonnens A nedre del, foljer darefter den genom pilarna antydda vagen och strommar uppifran in i katalyskammaren vid en tillrackligt hog temperatur for att inleda reaktionen, dvs. vid ungefar 400° C. The mixture of nitrogen and cotton, which is under high pressure, coming from a high-pressure compressor M, flows through the heat exchanger D, which Or arranged in the lower part of the synthesis column A, then follows the scale indicated by the arrows and flows from above into the catalytic chamber at a sufficiently high temperature. to initiate the reaction, i.e. at about 400 ° C.

Katalysatormassan dr uppdelad i olika skik B1, B2, B3, B4, vilka uppbaras av rostar. Gasen lamnar det forsta skiktet vid en temperatur av ungefar 550° C, strommar genom kylanordningen C1, och nedkyles till ungefar 450° C. Vattnet i roret C1 uppvarmes och erhMler darigenam en lagre specifik vikt, sa att en sjalvcirkulation uppstar, tack vare vilken del ge- '2— — nom reaktionen alstrade v5.rmet avgives till vattnet, sum befinner sig i angpannan L. Med hjalp av ventilen H anpassas vattengenomstromningen till reaktionens intensitet. Pft analogt salt regleras gasernas temperatur i de. efterftiljande skikten av katalysatormassan med hjalp av kylanordningarna G2 och G3 samt ventilerna I-L och H3, sa att ett avtagande ternperaturfall uppnas, vilket erfordras for uppnaendc av ett h8gt omyandlingsutbyte. Sedan de katalyserande gaserna avgivit sitt varme i varmevaxlaren D, kylas de ytterligare i kylaren E. Den kondenserade ammoniaken avskiljes i karlet M medan de gaser, vilka icke reagerat, medelst pumpen G ater transporteras till synteskolonnen A. The catalyst mass is divided into different layers B1, B2, B3, B4, which are supported by rust. The gas leaves the first layer at a temperature of about 550 ° C, flows through the cooling device C1, and is cooled to about 450 ° C. The heat generated by the reaction is given off to the water, the sum of which is in the boiler L. With the aid of the valve H, the water flow is adapted to the intensity of the reaction. Pft analogue salt regulates the temperature of the gases in the. the subsequent layers of the catalyst mass with the aid of the cooling devices G2 and G3 as well as the valves I-L and H3, so that a decreasing temperature drop is achieved, which is required to achieve a high conversion yield. After the catalytic gases have given off their heat in the heat exchanger D, they are further cooled in the cooler E. The condensed ammonia is separated in the vessel M while the unreacted gases are transported to the synthesis column A by means of the pump G.

Expansionskarlet P, i vilket det fran termosif oncirkulationen harrarande -varmvattnet ansamlas, star Over rorledningen Q i fdrbindelse med ammoniakavskiljaren F. For att undvika att vattenangan intranger i synteskretsloppet Hiles expansionskarlet P yid en temperatur under vattnets kritiska temperatur. Tack vare detta arrangemang hailer sig vattnets tryck i det lure av roren C1, C>, C3 praktiskt taget lika med del i katalyskamma ren A radande trycket, si att det aven yid mycket haga drift stryck ar inojligt att anvanda rOr med tunna vaggar, varigenom avsevarda besparingar garas med avseende pa byggnadskostnader vid konstruktionen av reaktionskammaren. The expansion vessel P, in which the hot water from the thermosif oncirculation accumulates, stands above the pipeline Q in connection with the ammonia separator F. To prevent the water vapor from entering the synthesis circuit, the expansion vessel P is at a temperature below the critical temperature of the water. Thanks to this arrangement, the pressure of the water rises in the lure of the pipes C1, C>, C3 practically equal to part of the catalytic converter A radiating pressure, in that even at very high operating pressures it is impossible to use pipes with thin cradles, whereby Significant savings are made with respect to construction costs in the construction of the reaction chamber.

Naturligtvis kan man sum kylvatska aven anvanda andra vatskor an vatten. Of course, some cooling water can also be used other water shoes than water.

Claims

1. A method for carrying out exothermic high-pressure reactions according to claim 1 in patent 149 378, characterized in that the heat of reaction is dissipated by means of heat exchangers arranged in the catalytic chamber, in which water under pressure circulates according to the thermocyphon principle and gives off heat to an above, expansion vessel Is the water Mlles yid circulating according to the thermosyphon principle a temperature below the critical temperature of the water and is in connection with the synthesis circuit. Request publications: Stockholm 1061. Rungl. Boktr. P. A. Norstedt & Semen 610089 LITOGR. INSTITUTION