SU44238A1 - The method of using the heat of reaction for the formation of ammonia or methanol - Google Patents

Description

The formation of ammonia from elements under high pressure, in the presence of a catalyst, is a highly exothermic reaction. The amount of heat released reaches 750-800 calories per kg of ammonia formed. With the formation of 1 kg of methanol, the amount of reaction heat exceeds 850-900 calories.

In modern synthesis columns, gas passes through a catalyst at an average of about 20 / o from the weight of the total gas to ammonia or methanol, which makes it possible to raise the temperature of 1 kg of the gas mixture due to the heat of formation by 120-160 °. If a heat exchanger for heat recovery is created in the synthesis column, providing a heat differential of 10–20 ° and relying on losses of 1-2 °, which is quite enough, then obviously it can be used near reaction heat for outsiders for the process.

An example is the “Nitrogen” column with a heat exchanger size of 120 m, always operating with a bypass of 20–30%. The temperature of the gas inlet in the catalyst box is about 400. The capacity of the column is 1.4 / those of ammonia per hour. The heat of reaction is 780 calories per kg of ammonia produced. The amount passing through

gas column 8000 kg / h. The bypass gas inside the column is heated from 15 to 400 ° C, hence the heat exchange unnecessarily recovers heat: 8000.0.9-0.2. (400-15) 554400 cal1h

Here 0.9 is the heat capacity of 1 kg of the gas mixture.

It should be borne in mind that the temperature of the gas leaving the column is still very high at 160-170 °.

Thus, even with a heat exchanger size of 120 m, as in the Nitrogen column, it is possible without any damage to the process to remove 554400 calories of heat per hour from the column. Creating a more intensive heat exchanger working at a smaller temperature difference at the gas outlet from it, for example 40-15 25 °, where 15 is the temperature of the gas inlet to the heat exchanger, it will be possible to use up to 90% of the reaction heat, which in our example would be 1400.730. 0.9 980000 cal1 hour or 1140 kilowatt of power.

If we take the efficiency of machines for the transformation of energy into, then the useful power will be 342 kilowatts.

The heat of reaction can be used to produce water vapor or mechanical energy in such a way that liquid

mercury that evaporates due to heat lost. The mercury vapor formed is removed from the column and is condensed by cooling with boiling water under pressure up to 20 atm. Due to the heat of condensation, water vapor is removed. Liquid mercury is again returned by gravity to the column as shown in the attached diagram 2, where the following symbols are taken: 7-synthesis column, 2-heat exchanger, 3- steam boiler with mercury heating, 4-

mercury vapor conduit and 5 mercury liquid conduit.

The subject matter of the invention.

1. A method of using the heat of reaction for the formation of ammonia or methanol, characterized in that liquid mercury is introduced into the heat exchange device of the catalyst box of the synthesis column as a heat-removing medium, the resulting vapors are used as heating medium in the steam boiler.