CN216456929U

CN216456929U - Ammonia still system of direct steam heating

Info

Publication number: CN216456929U
Application number: CN202122602953.3U
Authority: CN
Inventors: 杨雪松
Original assignee: Acre Coking and Refractory Engineering Consulting Corp MCC
Current assignee: Acre Coking and Refractory Engineering Consulting Corp MCC
Priority date: 2021-10-27
Filing date: 2021-10-27
Publication date: 2022-05-10
Anticipated expiration: 2031-10-27

Abstract

The utility model relates to an ammonia still system heated by direct steam, which comprises an ammonia still, a steam blowing kettle and an ammonia still wastewater pump, wherein the ammonia still is connected with the steam blowing kettle; through add the evaporation and blow cauldron in ammonia still outside, with the production of tar sediment and deposit by evaporating the ammonia still bottom transfer to evaporate and blow the cauldron, during ammonia still operation, need not regularly arrange sediment operation, the pipeline blockage phenomenon of unloading can not appear, need not to stop work and handle, has guaranteed the continuous steady operation of ammonia still.

Description

Ammonia still system of direct steam heating

Technical Field

The utility model relates to the technical field of coal gas purification in the coking industry, in particular to an ammonia still system adopting direct steam heating in an ammonia still unit.

Background

Ammonia is a nitrogen-containing compound that is a by-product of the coal coking process. Generally, dry coal contains about 2% of nitrogen, 40-50% of the nitrogen enters raw gas, most ammonia is formed, and a small part of the nitrogen forms hydrogen cyanide and pyridine.

Ammonia gas is a colorless gas, has a strong pungent odor, is very soluble in water, and the aqueous solution is called ammonia water.

The raw gas from coke oven is a complex mixture composed of dry gas, water vapor and a series of chemical substances, and after being treated by a gas purification device, the chemicals such as tar, ammonia, benzene and the like are recovered, and the purified gas is sent to users for use. After raw gas discharged from the furnace passes through the riser, the raw gas is sprayed and cooled to about 80 ℃ by using circulating ammonia water in a bridge pipe and a gas collecting pipe, the cooled tar is about 60 percent, the raw gas is sent to a gas-liquid separator for gas-liquid separation, a tar ammonia water mixed solution in the tar ammonia water mixed solution is separated and then enters an air-jet washing tower, the ammonia water is used for continuously and circularly washing coal powder carried in the gas, then the gas is pumped to a primary cooler and is indirectly cooled by circulating water and low-temperature water, and finally the gas is cooled to 20-21 ℃, and the purification effect of the gas is improved. And after the oil-water residue separation is carried out on all the cooled mixed liquor, the ammonia water is reused for circulating cooling, in the process, the circulating ammonia water collects the water (accounting for about 12% of the coal gas amount) contained in the raw coke oven gas, the circulating ammonia water amount is gradually increased, the redundant part of the circulating ammonia water is called residual ammonia water, and the residual ammonia water is sent to a wastewater treatment system after being treated by an ammonia distillation unit of a coal gas purification device.

The purpose of the ammonia distillation unit is to decompose volatile ammonium salts (such as ammonium carbonate, ammonium sulfide and the like) in raw ammonia water by heating the ammonia water, so that carbon dioxide, hydrogen sulfide and ammonia escape from the top of the tower in a gaseous state; meanwhile, in order to decompose and fix ammonium salts (such as ammonium sulfate and ammonium chloride), a sodium hydroxide solution is added into the middle section of the ammonia still. The ammonia still has two processes of direct steam heating and indirect steam heating, wherein the direct steam heating mode can simplify the flow, reduce the temperature of the bottom of the ammonia still and save energy.

The residual ammonia water is removed with impurities through a steam-floating tar remover and a ceramic filter before being sent to an ammonia still contains a small amount of tar, the tar enters the ammonia still along with the ammonia water, and tar residues are accumulated at the bottom of the ammonia still. In the prior art, the ammonia still only carries out emptying treatment, namely emptying to a tar slag pit. Because the tar residues contain fine coal powder, calcium hydroxide, magnesium hydroxide and other precipitates, and direct steam heating is adopted, the bottom of the ammonia still is in a boiling state, the tar residues are deposited on the whole inner wall of the bottom of the tower and form a thick and firm tar residue layer, so that the tower is not easy to empty, the shutdown is often needed, the slag removal treatment is carried out on the inner wall of the bottom of the tower through manpower, the ammonia still needs 365 days of uninterrupted continuous operation, and 2 ammonia stills are needed to be arranged on site, one is opened and the other is prepared.

The utility model discloses a chinese utility model patent that the grant publication number is CN209210559U discloses a "surplus aqueous ammonia removes tar device", establishes tar sediment precipitation bucket in the ammonia still tower bottom blow-off pipe exit that adopts direct steam heating technology and is used for the tar sediment to deposit, however, because it adopts direct steam heating, is boiling state at the ammonia still tower bottom, and the tar sediment dispersion is on the tower bottom and tower wall, and the circumstances of hanging the sediment at the bottom of the tower can not be solved to the tar sediment of tower bottom blow-off pipe discharge, and the easy stifled problem of blow-off pipe does not solve.

Disclosure of Invention

The utility model provides a direct steam heating ammonia still system, which transfers the generation and deposition of tar residue from the bottom of the ammonia still to a steam blowing kettle by additionally arranging the steam blowing kettle outside the ammonia still, and during the operation of the ammonia still, the residue discharge operation is not required to be carried out at regular time, the blockage phenomenon of an emptying pipeline is avoided, the shutdown treatment is not required, and the continuous and stable operation of the ammonia still is ensured.

In order to achieve the purpose, the utility model adopts the following technical scheme:

a direct steam heated ammonia still system includes an ammonia still; the system also comprises a steam blowing kettle and an ammonia distillation wastewater pump; a steam blowing kettle is arranged below the outside of the ammonia still; the lower part of the steaming and blowing kettle is provided with a direct steam inlet, the top of the steaming and blowing kettle is provided with a steam and blowing outlet and an ammonia distillation wastewater inlet, and the bottom of the steaming and blowing kettle is provided with an ammonia distillation wastewater outlet; the lower part of the ammonia still is provided with a direct steam inlet and a steam blowing inlet, and the bottom of the ammonia still is provided with a first ammonia still wastewater outlet and a second ammonia still wastewater outlet; a direct steam inlet of the steaming and blowing kettle is connected with a steam main pipe through a steam pipeline I, and a direct steam inlet of the ammonia still is connected with the steam main pipe through a steam pipeline II; a steam-blowing outlet of the steam-blowing kettle is connected with a steam-blowing inlet of the ammonia still through a steam-blowing pipeline; an ammonia distillation wastewater outlet I of the ammonia distillation tower is connected with an ammonia distillation wastewater inlet of the steam blowing kettle through an ammonia distillation wastewater pipeline I; an ammonia evaporation wastewater outlet of the steam blowing kettle is connected with an inlet of an ammonia evaporation wastewater pump through an ammonia evaporation wastewater pipeline II, and an outlet of the ammonia evaporation wastewater pump is connected with an ammonia evaporation wastewater pipeline; the ammonia distillation wastewater outlet II is connected with an ammonia distillation wastewater pipeline II through an ammonia distillation wastewater pipeline III.

The steam-blowing kettle is a horizontal kettle.

The direct steam inlet of the steaming and blowing kettle is provided with a direct steam heating pipe, the direct steam heating pipe is connected with the kettle body of the steaming and blowing kettle through a flange, the direct steam heating pipe is horizontally arranged, one end of the direct steam heating pipe is connected with a first steam pipeline, and the other end of the direct steam heating pipe extends into the steaming and blowing kettle.

An ammonia evaporation wastewater pipe is arranged at an ammonia evaporation wastewater inlet of the steaming and blowing kettle and is connected with a kettle body of the steaming and blowing kettle through a flange, the ammonia evaporation wastewater pipe is vertically arranged, one end of the ammonia evaporation wastewater pipe is connected with a first ammonia evaporation wastewater pipeline, and the other end of the ammonia evaporation wastewater pipe extends into the steaming and blowing kettle.

The kettle body of the steam blowing kettle is provided with a seal head at one end corresponding to the direct steam inlet, and the kettle body is connected with the seal head through a flange.

And the lower part of the ammonia still is provided with an ammonia still wastewater return port which is connected with an outlet of an ammonia still wastewater pump through an ammonia still wastewater pipeline IV.

The first steam pipeline is provided with a first valve, and the second steam pipeline is provided with a second valve; a third valve is arranged on the steam blowing pipeline; a fourth valve is arranged on the ammonia distillation wastewater pipeline I, a fifth valve is arranged on the ammonia distillation wastewater pipeline II, a sixth valve is arranged on the ammonia distillation wastewater pipeline III, and a seventh valve is arranged on the ammonia distillation wastewater pipeline IV; and an ammonia distillation wastewater pipeline is provided with an eighth valve.

Compared with the prior art, the utility model has the beneficial effects that:

1) compared with the process of discharging the tar residue to a tar residue pit through an emptying pipeline at the bottom of the conventional ammonia still, the shutdown treatment caused by blockage of the emptying pipeline by the tar residue is avoided;

2) the conventional tar slag pit is cancelled, a steaming and blowing kettle is adopted, slag can be removed on site or after the steaming and blowing kettle is moved away, and the steaming and blowing kettle adopts a closed structure, so that the site environment can be purified;

3) when the evaporation and blowing kettle discharges slag, the mode of introducing direct steam to the bottom of the ammonia still for heating can be temporarily switched, the ammonia still does not need to be stopped, and the continuous production can be ensured.

Drawings

FIG. 1 is a schematic diagram of a direct steam-heated ammonia still system according to the present invention.

In the figure: 1. ammonia still tower 2, steam blowing kettle 3, ammonia still wastewater pump 4, valve one 5, valve two 6, valve three 7, valve four 8, valve five 9, valve six 10, valve seven 11, valve eight A1, direct steam inlet A2 of ammonia still tower, direct steam inlet A3 of steam blowing kettle, ammonia still wastewater inlet A4 of steam blowing kettle, steam blowing inlet A5, ammonia still wastewater return inlet B1, ammonia still wastewater outlet one B2, ammonia still wastewater outlet two B3, ammonia still wastewater outlet B4. steam blowing outlet

Detailed Description

The following further describes embodiments of the present invention with reference to the accompanying drawings:

as shown in FIG. 1, the direct steam heating ammonia still system of the present invention comprises an ammonia still 1; the system also comprises a steam blowing kettle 2 and an ammonia distillation wastewater pump 3; a steam blowing kettle 2 is arranged below the outside of the ammonia still 1; the lower part of the steaming and blowing kettle 2 is provided with a direct steam inlet A2, the top is provided with a steaming and blowing steam outlet B4 and an ammonia evaporation wastewater inlet A3, and the bottom is provided with an ammonia evaporation wastewater outlet B3; the lower part of the ammonia still 1 is provided with a direct steam inlet A1 and a steam blowing inlet A4, and the bottom is provided with a first ammonia still wastewater outlet B1 and a second ammonia still wastewater outlet B2; the direct steam inlet A2 of the steaming and blowing kettle 2 is connected with a steam main pipe through a steam pipeline I, and the direct steam inlet A1 of the ammonia still 1 is connected with the steam main pipe through a steam pipeline II; a steam-blowing outlet B4 of the steam-blowing kettle 2 is connected with a steam-blowing inlet A4 of the ammonia still 1 through a steam-blowing pipeline; the first ammonia distillation wastewater outlet B1 of the ammonia distillation tower 1 is connected with the first ammonia distillation wastewater inlet A3 of the steam blowing kettle 2 through a first ammonia distillation wastewater pipeline; an ammonia evaporation wastewater outlet B3 of the steaming and blowing kettle 2 is connected with an inlet of an ammonia evaporation wastewater pump 3 through an ammonia evaporation wastewater pipeline II, and an outlet of the ammonia evaporation wastewater pump 3 is connected with an ammonia evaporation wastewater pipeline; and the ammonia distillation wastewater outlet II B2 is connected with the ammonia distillation wastewater pipeline II through an ammonia distillation wastewater pipeline III.

The steam blowing kettle 2 is a horizontal kettle.

A direct steam heating pipe is arranged at a direct steam inlet A2 of the steaming and blowing kettle 2, the direct steam heating pipe is connected with a kettle body of the steaming and blowing kettle 2 through a flange, the direct steam heating pipe is horizontally arranged, one end of the direct steam heating pipe is connected with a first steam pipeline, and the other end of the direct steam heating pipe extends into the steaming and blowing kettle 2.

An ammonia evaporation wastewater pipe is arranged at an ammonia evaporation wastewater inlet A3 of the steaming and blowing kettle 2, the ammonia evaporation wastewater pipe is connected with the kettle body of the steaming and blowing kettle 2 through a flange, the ammonia evaporation wastewater pipe is vertically arranged, one end of the ammonia evaporation wastewater pipe is connected with a first ammonia evaporation wastewater pipeline, and the other end of the ammonia evaporation wastewater pipe extends into the steaming and blowing kettle 2.

An end socket is arranged at one end of the kettle body of the steam blowing kettle 2, which corresponds to the direct steam inlet A2, and the kettle body is connected with the end socket through a flange.

The lower part of the ammonia still 1 is provided with an ammonia still wastewater return opening A5 which is connected with the outlet of the ammonia still wastewater pump 3 through an ammonia still wastewater pipeline IV.

A first valve 4 is arranged on the first steam pipeline, and a second valve 5 is arranged on the second steam pipeline; a third valve 6 is arranged on the steam blowing pipeline; a valve IV 7 is arranged on the ammonia distillation wastewater pipeline I, a valve V8 is arranged on the ammonia distillation wastewater pipeline II, a valve VI 9 is arranged on the ammonia distillation wastewater pipeline III, and a valve VII 10 is arranged on the ammonia distillation wastewater pipeline IV; and an ammonia distillation wastewater pipeline is provided with an eighth valve 11.

The utility model relates to a slag discharging method of a direct steam heating ammonia distillation tower system, which comprises the following steps: the liquid is not stored at the bottom of the ammonia still, the ammonia still wastewater is directly discharged into the steaming and blowing kettle 2, the steaming and blowing kettle 2 adopts direct steam heating, the tar residue in the ammonia still wastewater is deposited in the steaming and blowing kettle 2, after the tar residue is deposited for a period of time, the steaming and blowing kettle 2 is off-line cleaned, and simultaneously the system is switched to a mode of introducing direct steam to the bottom of the ammonia still for heating; and after the slag removal of the steaming and blowing kettle 2 is finished, the system is switched to a mode of introducing direct steam into the steaming and blowing kettle 2 for heating again.

According to the utility model, the evaporation-blowing kettle is adopted for heating, and the deposition position of the tar residue is transferred to the evaporation-blowing kettle from the bottom of the ammonia still, so that the ammonia still is effectively protected; the utility model can be switched back to the bottom of the ammonia still for direct steam heating operation in a short period, and realizes slag removal operation of the steam blowing kettle without shutdown.

The following examples are carried out on the premise of the technical scheme of the utility model, and detailed embodiments and specific operation processes are given, but the scope of the utility model is not limited to the following examples.

[ examples ] A method for producing a compound

In this embodiment, a direct steam heating ammonia still system includes ammonia still 1, evaporates and blows cauldron 2, ammonia still waste water pump 3, valve one 4, valve two 5, valve three 6, valve four 7, valve five 8, valve six 9, valve seven 10, valve eight 11.

Firstly, 1 horizontal steaming-blowing kettle 2 is additionally arranged on the ground below the outside of an ammonia still 1 and used for replacing the function of directly heating the steam at the bottom of the ammonia still 1, the ammonia still 1 is an empty tower, and no liquid is stored at the bottom of the tower.

In order to enable the steaming and blowing kettle 2 to have the function of direct steam heating steaming and blowing and conveniently carry out manual deslagging, a steaming and blowing steam outlet B4 and an ammonia evaporation wastewater inlet A3 are arranged at the top of the steaming and blowing kettle 2, a direct steam inlet A2 is arranged on one side of the lower part of the steaming and blowing kettle 2, and an ammonia evaporation wastewater outlet B3 is arranged at the bottom of the steaming and blowing kettle. Extend to the other end of evaporating and blowing cauldron 2 from direct steam inlet level male direct steam heating pipe, from the vertical male ammonia still waste pipe of ammonia still waste water inlet A3 department extends to the bottom of evaporating and blowing cauldron 2, direct steam heating pipe and ammonia still waste pipe homoenergetic take out from evaporating and blowing cauldron 2, evaporate and blow cauldron 2 and establish the head in one side that corresponds direct steam heating pipe, adopt flange joint between head and the cauldron body, carry out manual slag removal after convenient to detach.

The tower bottom of the ammonia still 1 is not provided with a blow-down pipe, but is provided with a first ammonia still wastewater outlet B1 and a second ammonia still wastewater outlet B2, and the first ammonia still wastewater outlet B1 is connected with an ammonia still wastewater inlet A3 of the steam blowing kettle 2 and is used for emptying the ammonia still wastewater at the bottom of the ammonia still 1 in the ammonia still operation process.

The lower part of ammonia still 1 establishes on the tower lateral wall of the highest liquid level top in the bottom of the tower and evaporates and blows steam inlet A4 and ammonia still waste water and return mouth A5, and steam inlet A4 is used for through evaporating and blowing steam pipe connection evaporate and blow cauldron 2 top evaporate and blow steam outlet B4, and ammonia still waste water returns mouth A5 and is used for evaporating and blows cauldron 2 and when carrying out off-line row sediment operation, sends back ammonia still waste water that evaporates and blows cauldron 2 exhaust among the system switching process to ammonia still 1 through evaporating ammonia waste water pump 3.

The ammonia distillation wastewater discharged from the ammonia distillation wastewater outlet B2 of the ammonia distillation tower 1 and the ammonia distillation wastewater outlet B3 of the steam blowing kettle 2 share one ammonia distillation wastewater pump 3, namely, no matter the direct steam heating is carried out on the steam blowing kettle 2 or the bottom of the ammonia distillation tower 1, the ammonia distillation wastewater is sent to an ammonia distillation wastewater pipeline by adopting the same ammonia distillation wastewater pump 3.

The external direct steam is simultaneously connected with the direct steam inlet A1 of the ammonia still 1 and the direct steam inlet A2 of the steam blowing kettle 2, and can supply heat to the ammonia still 1 and the steam blowing kettle 2.

The specific operation process is as follows:

1. during normal production, the second valve 5, the sixth valve 9 and the seventh valve 10 are closed, and the other valves are opened; all ammonia evaporation wastewater in the ammonia evaporation tower 1 is discharged into the steaming and blowing kettle 2 through a first ammonia evaporation wastewater pipeline, and steam in a steam main pipe is introduced into the steaming and blowing kettle 2 through a first steam pipeline and a direct steam heating pipe to heat the steaming and blowing kettle 2; tar residue in the ammonia distillation wastewater is deposited at the bottom of the distillation kettle 2; the ammonia evaporation wastewater in the steam blowing kettle 2 is pumped by an ammonia evaporation wastewater pump 3 and then is sent into an ammonia evaporation wastewater pipeline;

2. when tar residues in the steaming and blowing kettle 2 are deposited to a certain thickness and need to be cleaned, switching the system; closing the valve IV 7; opening a valve six 9 and a valve seven 10, pumping the ammonia distillation wastewater at the bottom of the ammonia distillation tower in the switching process through an ammonia distillation wastewater pump 3 and then sending the ammonia distillation wastewater back to the ammonia distillation tower 1;

3. after the system is switched, closing the first valve 4, the third valve 6, the fourth valve 7, the fifth valve 8 and the seventh valve 10, and opening the other valves; the steam blowing kettle 2 is cleaned off line; steam in the steam main pipe enters the ammonia still 1 through a steam pipeline II to heat the bottom of the ammonia still, and ammonia still wastewater in the ammonia still 1 is pumped out by an ammonia still wastewater pump 3 and then is sent into an ammonia still wastewater pipeline;

4. and the steam blowing kettle 2 is on line again after being cleaned, and the system is switched back to the normal production mode.

The above description is only for the preferred embodiment of the present invention, but the scope of the present invention is not limited thereto, and any person skilled in the art should be considered to be within the technical scope of the present invention, and equivalent alternatives or modifications according to the technical solution of the present invention and the inventive concept thereof should be covered by the scope of the present invention.

Claims

1. A direct steam heated ammonia still system includes an ammonia still; it is characterized by also comprising a steam blowing kettle and an ammonia distillation waste water pump; a steam blowing kettle is arranged below the outside of the ammonia still; the lower part of the steaming and blowing kettle is provided with a direct steam inlet, the top of the steaming and blowing kettle is provided with a steam and blowing outlet and an ammonia distillation wastewater inlet, and the bottom of the steaming and blowing kettle is provided with an ammonia distillation wastewater outlet; the lower part of the ammonia still is provided with a direct steam inlet and a steam blowing inlet, and the bottom of the ammonia still is provided with a first ammonia still wastewater outlet and a second ammonia still wastewater outlet; a direct steam inlet of the steaming and blowing kettle is connected with a steam main pipe through a steam pipeline I, and a direct steam inlet of the ammonia still is connected with the steam main pipe through a steam pipeline II; a steam-blowing outlet of the steam-blowing kettle is connected with a steam-blowing inlet of the ammonia still through a steam-blowing pipeline; an ammonia distillation wastewater outlet I of the ammonia distillation tower is connected with an ammonia distillation wastewater inlet of the steam blowing kettle through an ammonia distillation wastewater pipeline I; an ammonia evaporation wastewater outlet of the steam blowing kettle is connected with an inlet of an ammonia evaporation wastewater pump through an ammonia evaporation wastewater pipeline II, and an outlet of the ammonia evaporation wastewater pump is connected with an ammonia evaporation wastewater pipeline; the ammonia distillation wastewater outlet II is connected with an ammonia distillation wastewater pipeline II through an ammonia distillation wastewater pipeline III.

2. The direct steam heated ammonia still system as claimed in claim 1, wherein the steam blowing tank is a horizontal tank.

3. The ammonia still system of claim 1, wherein a direct steam heating pipe is disposed at a direct steam inlet of the steaming and blowing kettle, the direct steam heating pipe is connected to a kettle body of the steaming and blowing kettle by a flange, the direct steam heating pipe is horizontally disposed, one end of the direct steam heating pipe is connected to the first steam pipeline, and the other end of the direct steam heating pipe extends into the steaming and blowing kettle.

4. The direct steam heating ammonia still system as claimed in claim 1, wherein the ammonia still wastewater inlet of the steam blowing kettle is provided with an ammonia still wastewater pipe, the ammonia still wastewater pipe is connected with the kettle body of the steam blowing kettle by a flange, the ammonia still wastewater pipe is vertically arranged, one end of the ammonia still wastewater pipe is connected with the first ammonia still wastewater pipe, and the other end of the ammonia still wastewater pipe extends into the steam blowing kettle.

5. The ammonia still system heated by direct steam as claimed in claim 1, wherein the tank body of the steaming and blowing tank is provided with a seal head at one end corresponding to the direct steam inlet, and the tank body is connected with the seal head through a flange.

6. The direct steam heating ammonia still system as claimed in claim 1, wherein the lower part of the ammonia still is provided with an ammonia still wastewater return port, and the outlet of the ammonia still wastewater pump is connected through an ammonia still wastewater pipeline four.

7. The direct steam heating ammonia still system as claimed in claim 1, wherein the first steam pipeline is provided with a first valve, and the second steam pipeline is provided with a second valve; a third valve is arranged on the steam blowing pipeline; a fourth valve is arranged on the ammonia distillation wastewater pipeline I, a fifth valve is arranged on the ammonia distillation wastewater pipeline II, a sixth valve is arranged on the ammonia distillation wastewater pipeline III, and a seventh valve is arranged on the ammonia distillation wastewater pipeline IV; and an ammonia distillation wastewater pipeline is provided with an eighth valve.