JP2006522911A - How to cool hot gas instantaneously - Google Patents

Abstract

The invention relates to a quench device for suddenly cooling a hot gas stream with the aid of quench water. The inventive quench device comprises a gas supply line and a gas drainage pipe. Said quench water is at least partially cooled by means of a heat exchanger. In addition, said quench device is provided with a cooling water circuit for cooling the first area of the gas stream and with a second separate cooling circuit which cools a second area of the gas stream and is arranged downstream.

Description

Field of Invention

  The invention relates to the instantaneous cooling of hot gas by means of the device according to claim 1 and the method according to claim 9 of the present application. The invention further relates to a method of using the apparatus and method according to the invention in a hot recirculation process according to claim 15.

  In many applications in high temperature process technology, the waste gas is instantaneously cooled by adding a liquid such as water. This is referred to as the “quenching” method, and the device used for this is the so-called “quenching device”.

  Water is circulated by a quench pump. Between the water inlet and outlet, the cooling water is heated by about 10-30 ° C. This thermal energy is extracted from the apparatus by a quench heat exchanger.

  In addition to the cooling of the gas, foreign substances contained in the gas are also condensed in the liquid. Contamination of heat exchangers, pipelines and equipment for conveying cooling water is inevitable. Therefore, repeated cleaning is necessary.

  An object of the present invention is to provide an apparatus and a method that can cool a gas extremely efficiently and secondly reduce a cleaning operation to a minimum. Furthermore, the present invention aims to provide a method of using such an apparatus and method.

  This object is achieved by an apparatus according to claim 1, a method according to claim 9 and a method of use according to claim 15.

DESCRIPTION OF PREFERRED EMBODIMENTS

  In order to solve the problem of the present invention of rapidly cooling a hot gas, the development of a two-stage quenching process has been proposed. In two stages or regions of hot gas flow that are arranged continuously along the direction of hot gas flow, the cooling is performed by two separate circuits. Thus, the cooling water is maintained in a circulating state in two separate circuits.

  The circuit 1 is used for the actual quenching of the hot gas in the first region along the gas flow direction, where the solid particles contained in the gas are also condensed here. The circuit 2 is used for final cooling to a final temperature in a second region along the gas flow direction.

In accordance with the present invention, there is also provided a method of use of each such apparatus or method for cooling synthesis gas generated in a hot recirculation process.
The effect of the present invention resides in the localization of solid particles that are condensed by quenching in a limited cooling zone. In combination with the embodiments described below, the condensed solid particles make it possible to completely avoid contamination of the heat exchanger.

  The quenching heat exchanger is preferably arranged alone in the cleaning circuit 2. The energy contained in the hot gas is consumed by these quenching heat exchangers. Eventually, circuit 1 or a practical quench circuit is implemented without a heat exchanger. Thus, contamination of the first cooling circuit is significantly eliminated.

  The quenching device is preferably a narrow device with inner pipes arranged concentrically, and hot gas entering the inner pipe from the top flows through the device from the top to the bottom. In the lower region, the gas is deflected by the deflecting device and then flows upward in the outer annular gas and leaves the device at the upper end. The inner pipe is cooled to 1000 ° C. to 2000 ° C. to 95 ° C. to 70 ° C., particularly preferably 85 ° C., and the outer annular gap is cooled to 85 ° C. to 70 ° C. to 40 ° C., preferably 60 ° C. The

In a preferred variant of the device according to the invention, the cooling water is discharged by free overflow from circuit 2 to circuit 1.
In another preferred embodiment, the coolant level in circuits 1 and 2 is controlled by the coolant level in circuit 1. The mechanism for adjusting the liquid level is preferably realized by supplying water to the circuit 1 or discharging water from the circuit 1.

  In the process according to the invention, waste gas at a temperature of 1000 ° C. to 2000 ° C., preferably 1200 ° C. is preferably quenched. In the first region, preferably including the inner pipe, rapid cooling of the hot gas from a temperature of 1200 ° C. to 95 ° C. to 70 ° C., preferably 85 ° C. occurs.

The process according to the invention is preferably carried out on waste gas having a water content of 10 to 70% by volume, particularly preferably 30% by volume.

Claims (15)

A quenching device for quenching a flow of hot gas with the aid of cooling water, comprising a supply line and a gas discharge pipe, wherein the cooling water is at least partially cooled by a heat exchanger,
A cooling water circuit for cooling the first region of the gas flow, and a separate second cooling water circuit for cooling the region of the gas flow downstream of the first region. A cooling device characterized by. The quenching device according to claim 1,
The rapid cooling apparatus, wherein only the second cooling circuit is provided with a heat exchanger for cooling the cooling water. The quenching device according to any one of claims 1 to 2,
A quenching device comprising an overflow portion from the second cooling circuit to the first cooling circuit. The quenching device according to any one of claims 1 to 3,
A quenching device characterized in that a mechanism for controlling the liquid level of the cooling water in the first cooling circuit is provided. The quenching device according to claim 4,
The mechanism for controlling a coolant level in the first cooling circuit supplies the cooling water to the first circuit and discharges the cooling water from the first circuit, thereby cooling the cooling water. A quenching device comprising adjusting the level of water. The quenching device according to any one of claims 1 to 5,
The first region of the gas flow is bounded by the inner wall of an upright cylindrical inner pipe, and the gas supply line for the quenching device is located at the upper end of the pipe A quenching device characterized by. The quenching device according to claim 6,
The quenching device characterized in that the second region of the gas flow is bounded by an outer wall of the inner pipe and an inner wall of the outer pipe arranged concentrically around the inner pipe. . The quenching device according to claim 7,
A deflecting device attached to a lower region of the inner pipe and for deflecting a gas flow flowing downward in the inner pipe into a gas flow flowing upward in the outer pipe; A quenching device characterized by. A method for quenching a flow of hot gas by adding cooling water,
Cooling is performed in the first region of the gas flow by the cooling water from the first cooling circuit, and the first water cooling is performed in the second region of the gas flow downstream of the first region. A rapid cooling method characterized in that cooling is performed by cooling water from a second water cooling circuit separate from the circuit. The rapid cooling method according to claim 9,
Only the cooling water in the second cooling circuit is cooled by a heat exchanger. The rapid cooling method according to claim 9 or 10,
The rapid cooling method, wherein the gas in the first region of the gas flow flows in a direction opposite to the gas in the second region of the gas flow. The rapid cooling method according to any one of claims 9 to 11,
The gas in the first region of the gas flow has an initial temperature before cooling of 1000 ° C. to 2000 ° C., preferably 1200 ° C., and a temperature after cooling of 95 ° C. to 70 ° C., preferably 85 ° C. A rapid cooling method characterized by that. The rapid cooling method according to any one of claims 9 to 12,
The gas in the second region of the gas flow has an initial temperature before cooling of 95 ° C to 70 ° C, preferably 85 ° C, and a temperature after cooling of 70 ° C to 40 ° C, preferably 60 ° C. A rapid cooling method characterized by being. The rapid cooling method according to any one of claims 9 to 13,
A rapid cooling method characterized in that the gas to be cooled contains 10 to 70% by volume, preferably 30% by volume, of water. Use of the apparatus according to any one of claims 1 to 8 and the method according to any one of claims 9 to 15,
A method of use characterized in that it is used to quench the synthesis gas produced in a high temperature recirculation process.