CN-224207998-U - Ammonium nitrate recycling structure applied to ammonium nitrate thermal decomposition process

Abstract

The utility model relates to an ammonium nitrate recycle structure for ammonium nitrate thermal decomposition technology, including melting ware and reation kettle, melt the ware and be connected with reation kettle through the ammonium nitrate delivery pump, set up the control valve between ammonium nitrate delivery pump and the reation kettle, the decomposition gas rising section in reation kettle sets up cooling coil, cooling coil's feed liquor end is connected with melting the ware through the ammonium nitrate circulating pump, cooling coil's return liquid termination returns to melt the ware, use the ammonium nitrate solution in melting the ware as cooling medium in the cooling coil, with the nondegradable ammonium nitrate steam that rises along with nitrous oxide in the reation kettle heat transfer, form the liquid drip after making it condense and return to reation kettle and continue to carry out thermal decomposition, improve the utilization ratio of ammonium nitrate, the ammonium nitrate solution that is as cooling medium in the cooling coil is after the heat transfer intensification simultaneously, get back to in melting the ware, reduce the energy consumption that melting ware preheated the ammonium nitrate solution.

Inventors

• WANG JIAXIN
• LI WENBO
• REN XUE

Assignees

• 全椒科利德电子材料有限公司

Dates

Publication Date

20260508

Application Date

20250604

Claims (3)

1. 1. The utility model provides an ammonium nitrate recycle structure for ammonium nitrate thermal decomposition technology, including melting ware (1) and reation kettle (2), melt ware (1) and be connected with reation kettle (2) through ammonium nitrate delivery pump (3), set up control valve (4) between ammonium nitrate delivery pump (3) and the reation kettle, a serial communication port, decomposition gas in reation kettle (2) rises the section and sets up cooling coil (5), the feed liquor end of cooling coil (5) is connected with melting ware (1) through ammonium nitrate circulating pump (6), the return liquid end of cooling coil (5) returns to melt ware (1) for with the upward gas that ammonium nitrate thermal decomposition produced in reation kettle (2) carries out the heat transfer.
2. 2. The ammonium nitrate recycling structure according to claim 1, wherein an emergency cut-off valve (7) is arranged at the liquid inlet end of the ammonium nitrate circulating pump (6) and the cooling coil pipe (5).
3. 3. The ammonium nitrate recycling structure according to claim 2, characterized in that the cooling coil (5) is made of stainless steel.

Description

Ammonium nitrate recycling structure applied to ammonium nitrate thermal decomposition process Technical Field The utility model relates to the technical field of preparation of special working gas, in particular to an ammonium nitrate recycling structure applied to an ammonium nitrate thermal decomposition process. Background High purity nitrous oxide is used as an important raw material in the electronics industry, and in the process of manufacturing ICs (semiconductors) and LEDs (light emitting diodes), a silicon dioxide film generated by chemical reaction of nitrous oxide is deposited on the bottom of a silicon village, and serves as a buffer layer to prevent the entry of harmful impurities. With the development of LEDs and semiconductors, the demand for high purity nitrous oxide gas is increasing, and industrial high purity nitrous oxide synthesis mainly comes from ammonium nitrate decomposition. In the nitrous oxide synthesis process, nitrous oxide generated by decomposing an ammonium nitrate solution in a reaction kettle rises in the reaction kettle, is discharged from the top, and then enters the processes of filtering, condensing, washing, purifying and the like to finally obtain high-purity nitrous oxide. However, through practical tests, the decomposition rate of ammonium nitrate is not high, the gas rising in the reaction kettle contains the non-decomposed ammonium nitrate steam, and the part of ammonium nitrate steam enters the filter along with nitrous oxide generated by decomposition to become waste liquid to be treated, so that the production cost is greatly increased. Disclosure of utility model In order to solve the problems, the utility model provides an ammonium nitrate recycling structure applied to an ammonium nitrate thermal decomposition process, which utilizes ammonium nitrate which is not fed into a reaction kettle in a melter and is subjected to additive decomposition as condensate, and the rising ammonium nitrate steam of nitrous oxide in the reaction kettle is condensed and recycled. The technical scheme is that the ammonium nitrate recycling structure applied to the ammonium nitrate thermal decomposition process comprises a melter and a reaction kettle, wherein the melter is connected with the reaction kettle through an ammonium nitrate conveying pump, a control valve is arranged between the ammonium nitrate conveying pump and the reaction kettle, a cooling coil is arranged at a decomposition gas ascending section in the reaction kettle, a liquid inlet end of the cooling coil is connected with the melter through an ammonium nitrate circulating pump, and a liquid return end of the cooling coil is connected with the melter and is used for exchanging heat with ascending gas generated by thermal decomposition of ammonium nitrate in the reaction kettle. Further, an emergency cut-off valve is arranged at the liquid inlet ends of the ammonium nitrate circulating pump and the cooling coil. Further, the cooling coil is made of stainless steel. The utility model has the beneficial effects that the cooling coil is arranged at the decomposition gas rising section in the reaction kettle, and a circulation loop is formed by the ammonium nitrate circulating pump and the melter, the ammonium nitrate solution in the melter is used as a cooling medium in the cooling coil, so that the temperature of the non-decomposed ammonium nitrate steam rising along with nitrous oxide in the reaction kettle can be reduced, the non-decomposed ammonium nitrate steam forms liquid drops after heat exchange condensation, the liquid drops fall back to the reaction kettle under the action of gravity to continue thermal decomposition, and the ammonium nitrate solution serving as the cooling medium in the cooling coil returns to the melter after heat exchange and temperature rise, so that the energy consumption of preheating the ammonium nitrate solution by the melter is reduced. Drawings FIG. 1 is a schematic illustration of the present utility model; Fig. 2 is a schematic diagram of a cooling coil. The device is shown as the figure, 1, a melter, 2, a reaction kettle, 3, an ammonium nitrate delivery pump, 4, a control valve, 5, a cooling coil, 6, an ammonium nitrate circulating pump and 7, an emergency cut-off valve. Detailed Description Example 1 The reaction kettle is used for carrying out thermal decomposition on ammonium nitrate at the thermal decomposition reaction end in the traditional ammonium nitrate thermal decomposition process system, as the decomposition temperature of the ammonium nitrate in the reaction kettle needs to reach 245 ℃, an ammonium nitrate solution is usually preheated by a melter arranged in front of the reaction kettle end, and enters the reaction kettle for thermal decomposition when reaching 180 ℃, and ammonium nitrate steam in the reaction kettle leaves the reaction kettle along with nitrous oxide generated by decomposition and enters a filter, Referring to the drawings, as shown in fi