JPS6014747Y2 - Odor control equipment in the chemical district of a coke manufacturing plant - Google Patents

Description

[Detailed explanation of the invention] This invention is based on a recovery tank for recovering by-products such as tar and light oil generated from a coke oven, that is, a tar decanter.
In addition to direct suction and introduction of flammable gas-containing foul-smelling gases generated in storage tanks, light oil recovery equipment, light oil tanks, tar tanks, etc. that allow atmospheric air to be taken into the coke oven gas pipe, the coke oven A device that controls the flow rate of the flammable gas-containing foul-smelling gas to be introduced into the generated gas pipe to a constant level, eliminates the need for an odor removal device such as activated carbon, and does not cause an explosion of the foul-smelling gas. It is.

In a coke factory, the condensate containing coal tar generated during the gas cooling process, which is the first step in refining coke oven gas, is collected in a static tank called a tar decanter, where it is mixed with coal tar and gas liquid. Separated by standing.

Most of the gas liquid flows out as a supernatant liquid and is used again to cool the coke oven gas, while the surplus is sent to discharge treatment equipment such as activated sludge treatment equipment.

On the other hand, coal tar is pumped out from the bottom as sediment and sent to a tar storage tank.

In this way, the tar decanter and related equipment, which are essential for the first cooling process of coke oven gas, are used to prevent coke oven gas, ammonia, hydrogen sulfide, etc. dissolved in the gas liquid from accumulating in the gas liquid. Generates foul-smelling gas containing foul-smelling substances.

Conventionally, as a measure to control this odor, it has been generally considered to adopt methods such as cleaning methods, activated carbon adsorption methods, oxidative combustion methods, and catalytic oxidation methods after collecting the malodorous gases. Not only do they emit substances such as nitrogen oxides and nitrogen oxides, but the construction costs and operating costs are high, and when considering secondary and tertiary treatment, a huge amount of investment is required.

As a method to eliminate such inconveniences, a method is employed in which the malodorous gas is directly sucked into the coke oven gas treatment line through a pipe connected to the coke oven generated gas conduit and mixed into the coke oven gas. is proposed.

(Special Publication No. 54-21201).

In this case, specifically, the foul-smelling gas is pumped through the pipes while controlling the internal pressure of the generated gas and the atmosphere taken into the by-product recovery tank, such as a tar decanter or storage tank, from the atmosphere opening. However, in the case of such constant pressure control, the internal pressure is controlled to maintain a predetermined pressure, such as when the inspection hole cover is opened for internal inspection of a tar decanter or storage tank. Because of this, a large amount of outside air flows in through the inspection holes.

By the way, the foul-smelling gas contains gases composed of combustible components such as coke oven gas, so if a large amount of air is mixed with the foul-smelling gas, there is a risk that the gas inside the recovery tank will fall within the explosion limit, and as a result, There are safety shortcomings, including the risk of causing a catastrophe.

Furthermore, safety devices such as the pressure sensing part or water seal valve of a pressure detector are installed inside the tar decanter or storage tank, or at least communicate with the inside, so tar and naphthalene are removed. In such cases, accurate pressure cannot be detected, so
Inconveniences such as excessive negative pressure inside the tar decanter or storage tank may result in damage to the container.

The present invention was made to overcome these drawbacks of the conventional technology, and its gist is to improve storage tanks that handle gas liquids such as tar decanters, tar tanks, gas liquid tanks, etc.
Removes foul-smelling gases generated from light oil recovery equipment and light oil tanks.
In a coke oven gas processing system, the flow rate of malodorous gas flowing through the pipe is kept constant in the middle of the pipe, in a device that directly suctions and introduces gas into the coke oven gas treatment system through a pipe connected to the coke oven generated gas conduit. This is an odor control device for a chemical processing area of a coke manufacturing plant, which is characterized by being equipped with a constant flow rate control mechanism.

One embodiment will be described in detail below with reference to the drawings.

FIG. 1 is a process diagram showing an example of a coke oven gas cooling process, and FIG. 2 is a system diagram showing the flow of odor suction from a tar decanter.

The coke oven gas treatment system includes a coke oven 1, a riser pipe 2, a gas cooling tower 3, a gas discharge machine 4, and a gas purification equipment 9.
and the gas pipe connecting them 10at 10bt 1
It consists of 0c and 10d.

On the other hand, the condensate line system includes a condensation tank 5 and a tar decanter 6.
, gas liquid tank 7, pump 8, and gas liquid conduits 21, 22a, 22b, 23a connecting them.

23b, 24 and further related to the present invention are odor lines 31, 32 . Atmospheric release port 33 of tar decanter 6, etc.
It consists of

The coke oven gas generated from the coke oven 1 passes through the riser pipe 2, where it is pumped by the pump 8 into the gas liquid conduit 23at23.
It comes into contact with the gas liquid sent through b, cools down, flows through the coke oven generated gas conduit 10a together with the gas liquid, enters the gas cooler 3, is further cooled here, and is discharged from the gas discharge device 4 to the subsequent gas. It is pumped to the refining equipment 9.

On the other hand, the gas liquid flowing together with the coke oven gas is extracted from the lower part of the coke oven generated gas conduit 10a connected to the gas cooler 3, enters the tar decanter 6 via the gas liquid conduit 21, and enters the tar decanter 6 through the gas liquid conduit 21. The gas liquid from the tank enters the condensation tank 5 through the gas liquid conduit 22a, and flows into the tar decanter 6 through the gas liquid conduit 22b.

The tar decanter 6 is substantially sealed except for the air opening 33.

In addition, the atmosphere opening port 33 is used in constant flow control to be described later.
The opening area and shape are necessary and sufficient to suck in outside air to the extent that foul-smelling gas does not fall within the explosion limit.

The gas liquid that has flowed into the tar decanter 6 is allowed to stand still, and overflows while separating the tar mixed in the gas liquid, passes through the gas liquid conduit 23a, and enters the gas liquid tank 7.
The pump 8 sends it to the riser pipe 2 again.

Excess gas liquid is sent to the wastewater treatment facility through a gas liquid conduit 24 branched from the gas liquid conduit 23b.

In the deodorizing device of the present invention, a foul-smelling gas suction pipe 31 is provided in the tar decanter 6 or storage tank, which communicates with the air between the upper surface of the internal tar or gas liquid and the upper lid, and this is connected to the coke oven generated gas conduit 10a. In this method, the flow rate of the foul-smelling gas in the foul-smelling gas suction pipe 31 is controlled to be constant in a method in which the gas is introduced into the coke oven generated gas conduit 10a using the negative pressure generated by the gas discharge device 4.

The case of a tar decanter will be explained in detail based on FIG.

The foul-smelling gas suction pipe 31 is equipped with a flow rate detector 1 such as an orifice.
00, and a control valve 101 that receives signals from the flow rate detector 100 and automatically adjusts the opening degree of the valve so that a preset flow rate is obtained.

Further, an atmosphere opening port 33 is provided at an appropriate position of the tar decanter 6, and the opening area and shape of the atmosphere opening port 33 are determined by the inflowing air.
The decision is made after taking into account process control considerations to ensure that the flammable gas-containing foul-smelling gas in 6 does not reach the explosion limit, and to prevent blockages due to tar, naphthalene, etc.

With this structure, the foul-smelling gas generated in the tar decanter 6 is transported by the air from the atmosphere opening 33 and by the suction force of the gas exhaust device 4, and by the flow rate detector 100 and A constant flow rate control mechanism consisting of a flow rate control valve 101 allows the coke oven generated gas conduit 10 to be maintained at a constant flow rate.
is introduced by suction into a.

Note that 102 is a pressure gauge that detects the pressure in the upper space inside the tar decanter 6, and is provided as a guide for process control. For example, if the pressure is higher than normal for some reason, the set value of the control valve 101 can be increased, and vice versa, it can be lowered, allowing for more detailed process control. It becomes possible.

Since the present invention is constructed as described above, it is possible to reliably prevent the risk of explosion due to excessive inflow of air that occurs when controlling the pressure to a constant level in the conventional method of controlling the pressure in the tar decanter 6 at a constant level. This is an extremely useful device for safe operation because it can prevent foul-smelling gases from escaping into the outside air from the tar decanter or storage tank without installing a deodorizing device using activated carbon or the like.

[Brief explanation of the drawing]

FIG. 1 is a process diagram showing an example of a coke oven gas cooling process. FIG. 2 is a system diagram showing the flow of suctioning foul-smelling gas from the tar decanter. 1... Coke oven, 2... Rising pipe, 3
...gas cooling tower, 4...gas exhaust machine,
5... Condensation tank, 6... Tar decanter 17... Gas liquid tank, 8... Pump, 9... Gas purification equipment , 10a...
Coke oven generated gas pipes, 10b, 10c, 10d...
...Gas conduit, 21, 22a, 22b, 23a, 2
3b, 24... Gas liquid conduit, 31.32...
...Odor line, 33...Atmosphere opening, 10
0...Flow rate detector, 101...Flow rate control valve.

Claims (1)

[Scope of utility model registration request] A foul-smelling gas containing flammable gas generated in a recovery tank for byproducts generated from a coke oven and having an opening opening to the atmosphere is transferred to the coke oven through piping connected to a coke oven generated gas conduit in a coke oven gas treatment line. A device for direct suction and introduction into a furnace gas treatment line, characterized in that a constant flow rate control mechanism for controlling the flow rate of the flammable gas-containing foul-smelling gas to a constant level is provided in the middle of the piping, in a chemical processing area of a coke manufacturing plant. Odor control device.