JPS6313468B2 - - Google Patents

Description

[Detailed description of the invention]

The present invention relates to a cleaning method and apparatus for removing deposits from gas deposited on the outer peripheral surface of a cooling water pipe of a primary cooler that indirectly cools coke oven gas containing naphthalene, tar, etc. with cold water. The primary cooler in coke oven gas purification equipment is a gas blower 1 as shown in Figure 1.
The coke oven gas is introduced into the cooler main body 2 by suction, cooled, and naphthalene, tar, etc. in the gas are precipitated and separated, and then supplied to the gas purification device in the next step. That is, the cooler main body 2 has a large number of upper and lower baffle plates 2a and 2b arranged therein to form a zigzag gas flow path 2c on the upper and lower sides, and a large number of cooling water pipes 4 are arranged in the gas flow path 2c. A cooling water chamber 2f, formed on both sides of each cooling water pipe 4 by upper and lower partition plates 2d and 2e, and the upper and lower baffle plates 2a and 2b,
2g, and supply cooling water such as seawater or fresh water from a 4-inch supply pipe connected to the lower cooling water chamber 2g on the gas outlet side, and connect to the upper cooling water chamber 2f on the gas inlet side. Hot water drain pipe 4ou
The coke oven gas is indirectly cooled by flowing cooling water in the cooling water pipe 4 during the process. However, in the indirect cooling, after a long period of time, a large amount of precipitates from the gas adheres and accumulates on the outer circumferential surface of the cooling water pipe 4, reducing the gas cooling ability and losing the effect of removing the naphthalene, tar, etc. As a result, the gas associated with the contained substances is supplied to the next step, which greatly hinders the gas purification operation. As a result, deposits from the gas deposited on the outer circumferential surface of the cooling water pipe 4 must be periodically removed. The removal of the deposited deposits is carried out using the conventional gas flow path 2c.
Water sprinkler pipes 5 are arranged in a staggered manner inside the cooler body 2, and the introduction of coke oven gas into the cooler body 2 is temporarily stopped, and a large amount of heat stabilizer is applied from the water sprinkler pipes 5 to the outer peripheral surface of the large number of cooling water pipes 4 inside the cooler body 2. This is a method of washing and removing the attached deposits by spraying water. However, in this conventional method, since the cooling water pipes 4 are arranged in a staggered manner, it is difficult to uniformly spray hot ammonium water over the entire outer peripheral surface of each cooling water pipe 4, so that it is difficult to completely clean and remove the attached deposits. However, even if coke oven gas cooling is restarted, the original gas cooling capacity cannot be restored, and therefore the cleaning cycle has to be gradually shortened, and eventually the cleaning effect is lost. The cooler body 2 has to be stopped for a long time, and the operator has to mechanically remove the accumulated deposits from each cooling water pipe 4, one by one. Number of days (4-5
In addition to requiring many hours of labor, the cooler itself was shut down for a long period of time, which caused a great deal of trouble in the coke oven gas refining operation. On the other hand, due to long-term cooling water flowing through the inner walls of the cooling water pipes, a large amount of impurities in the cooling water precipitates and accumulates, significantly reducing the cooling capacity. One book had to be removed, and in some cases, replacement work was required. The present invention provides a method for supplying coke oven gas and cold water to a primary cooler to be cleaned when cleaning a primary cooler that indirectly cools the coke oven gas by introducing coke oven gas and introducing cold water into an internal cooling water pipe. The coke oven gas that has accumulated on the outer circumferential surface of the cooling water pipe of the primary cooler to be cleaned is removed by stopping the discharge and supplying and discharging already cooled heated waste water of 60°C or higher from the cooling water pipe of the operating primary cooler to the cooling water pipe of the primary cooler to be cleaned. A method for cleaning a primary cooler in coke oven gas purification equipment, which is characterized by removing precipitates from coke oven gas, and a cooling water supply pipe in which coke oven gas is introduced and an internal cooling water pipe is provided with an on-off valve. In a plurality of primary coolers that are connected to each other to supply cold water and connect cooled hot water discharge pipes with on-off valves to discharge cooled hot wastewater to indirectly cool the coke oven gas, A pump is connected to each of the cooling water supply pipe and the cooled hot water drain pipe via an on-off valve, and a control device is provided to control the combination of the on-off valves and drive the pump in accordance with the cleaning order of the primary cooler. This is a cleaning device for a primary cooler in a coke oven gas purification facility. That is, in the present invention, the reason why hot water of 60°C or higher is supplied to the cooling water pipe is that the deposits attached to the outer circumferential surface of the cooling water pipe are naphthalene, tar, etc. with a melting point of about 60°C, and these are removed from the inner wall surface of the cooling water pipe. By heating indirectly from the side, it can be melted and removed in a short time, and it is also possible to completely remove deposits deposited on the inner wall of the cooling water pipe. Therefore, the temperature of hot water should be 60℃
If the amount is less than that, there is no effect of removing deposits deposited on the inner and outer peripheral surfaces. In addition, as the hot water of 60°C or higher, it is possible to effectively use heated waste water discharged from an operating gas cooling system, and also to use hot water discharged from other equipment such as boilers and cooling equipment discharged from thermal power plants, steam generators, etc. This makes it possible to effectively utilize heated waste water, which is extremely advantageous in terms of energy saving, and allows cleaning at any time. In addition, when a large number of cooler bodies 2 are arranged in parallel like a primary cooler of coke gas purification equipment as in one embodiment of the apparatus shown in FIG.
A valve V ₁ is attached to the cooled hot water drain pipe 4ou of each cooler main body 2,
V ₂ is provided, the outlet side of the valve V ₂ is connected to a pump P, and the outlet side of this pump P is connected to the cooling water supply pipe 4 inches of each cooler main body 2 via a valve V ₃ . V ₁ , V ₂ , V ₃ and the main valve of the 4-inch supply pipe V ₄
Each opening/closing combination control and pump P drive control are
It is preferable to perform the cleaning on the cooler body 2 to be cleaned according to the cleaning order. With this device, it is possible to wash and remove adhering deposits from the inner and outer peripheral surfaces of the cooling water pipes 4 of each cooler main body 2 in a short cycle, and to constantly maintain the desired cooling performance and remove naphthalene-containing naphthalene from the gas to be cooled. , substantially all of the tar, etc. can be precipitated and recovered, eliminating any hindrance to the next process, and making it possible to greatly reduce the amount of cooling water used. Examples of the method and apparatus of the present invention will be described below. This example is an example of application to a primary cooler in coke oven gas purification equipment, and Table 1 below shows the situation at the beginning of operation and immediately before cleaning after 0.5 months.

[Table] Immediately before cleaning after 0.5 months, the introduction of coke oven gas was temporarily stopped and 70°C hot water was poured into the cooling water pipe.
After water was supplied for 5 hours at a rate of m ² /Hr, the inner and outer circumferential surfaces of the cooling water pipe were observed and found that there was virtually no deposited deposits on both surfaces. After this, coke oven gas was introduced again and operation was started, and the initial conditions shown in Table 1 were reliably obtained. After checking this, start the cleaning cycle.
As a result of carrying out the test every 0.5 months for 2 years, there were no deposits attached to the inner and outer circumferential surfaces of the cooling water pipes, and the cooling function of the cooling water pipes was stable at a high level, and the amount of seawater used was reduced to the same level as before.
Compared to 73,000m ³ /day, it was possible to reduce it to 49,300m ² /day, resulting in a savings of 23,700m ² /day. Further, the amount of tar and naphthalene contained in the coke gas after cooling was virtually non-existent. As is clear from the above description, the present invention eliminates the need for the above-mentioned operator to clean the cooling water pipes, and effectively utilizes heated waste water from an operating gas cooling device or other cleaning equipment to easily clean the cooling water pipes at any time. This equipment cleans the inner and outer circumferential surfaces of the cooling water pipes of gas cooling equipment, quickly and reliably removes deposits that have adhered to the circumferential surfaces, and restores the desired gas cooling performance. . This makes it possible to supply gas with the desired properties to the next process in the gas cooling system, allowing continuous and smooth gas processing operations, and also greatly reducing the amount of water supplied to the cooling water pipes, etc. In addition to the effective use of heated wastewater, it has an extremely large energy-saving effect, and brings extremely excellent industrial effects.

[Brief explanation of the drawing]

FIG. 1 is a schematic explanatory diagram of an example of a gas cooling device to which the present invention is applied, and FIG. 2 is an illustration of an example of the device according to the present invention.
FIG. 2 is a schematic explanatory diagram showing an example. In the figure, 1: gas blower, 2: cooler body, 4: cooling water pipe, 4in: cooling water supply pipe, 4
ou: Cooled hot water drain pipe, V ₁ , V ₂ , V ₃ , V ₄ : Open/close valve, P: Pump, Co: Control device.

Claims (1)

[Claims] 1. When cleaning a primary cooler that indirectly cools the coke oven gas by introducing coke oven gas and introducing cold water into an internal cooling water pipe, the coke oven gas and the coke oven gas to the primary cooler to be cleaned are The supply and discharge of cold water was stopped, and cooled heated waste water of 60°C or higher was supplied and discharged from the cooling water pipe of the operating primary cooler to the cooling water pipe of the primary cooler to be cleaned, and deposits were deposited on the outer peripheral surface of this cooling water pipe. A method for cleaning a primary cooler in coke oven gas purification equipment, the method comprising removing precipitates from coke oven gas. 2. Introduce coke oven gas, connect a cooling water supply pipe with an on-off valve to the internal cooling water pipe to supply cold water, and connect a cooled hot water drain pipe with an on-off valve to cool it down. In a plurality of primary coolers that indirectly cool the coke oven gas by discharging heated waste water of 1. A cleaning device for a primary cooler in a coke oven gas purification facility, comprising a control device that performs combined control of the above and drive control of the pump in accordance with the cleaning order of the primary cooler.