KR101275717B1 - Recycle system of coolling waste water for syngas - Google Patents

Abstract

The present invention relates to a recirculation system for syngas cooling and washing wastewater, and comprising: a wastewater storage tank (120) for storing cooling washing wastewater generated by cooling washing of syngas, and a cooling washing wastewater supplied from the wastewater storage tank (120). Backwashing apparatus 140 is provided with a plurality of backwash nozzles 144 along the longitudinal direction from the upper side of the filtration filter 142 so as to backwash the filtration filter 142, such as to filter through the (142). And a dehydration device 170 for separating the washing and cooling waste water washed through the backwashing device 140 into slurry and cooling water, and controlling the backwashing device 140 and the dewatering device 170 to control a predetermined amount of cooling water. It includes a control device 300 to be recycled to the cooling water supply tank (200). Therefore, the present invention can reduce the amount of use of the syngas cooling water and reduce the amount of wastewater generated by refining the cooling washing wastewater generated from the cooling scrubber for purifying the syngas and recycling it to the cooling washing machine. There is. In addition, it is also possible to sufficiently perform the cooling role by maintaining the same temperature as the initial cooling washing water by passing the cooling washing water recycled through the cooling device.

Syngas, Cooling, Wastewater, Recirculation, Backwashing

Description

Recirculation system of syngas cooling and washing waste water {RECYCLE SYSTEM OF COOLLING WASTE WATER FOR SYNGAS}

1 is a block diagram showing a recycling system for syngas cooling washing wastewater according to a preferred embodiment of the present invention,

2 is an enlarged view of a backwashing device according to an embodiment of the present invention,

3 is a flow chart of a method for recirculating syngas cooling wash wastewater according to an embodiment of the present invention.

<Description of the symbols for the main parts of the drawings>

100: cooling cleaner 110: circulation line

120: wastewater storage tank 130: wastewater supply pump

140: backwash device 141: case

1401a: inlet 142: filtration filter

143: motor 144: backwash nozzle

145: on-off valve 146: differential pressure gauge

150: backwash water storage tank 151: backwash supply pump

160: rescue soil supply device 170: dewatering device

171 filter 180 dewatering pump

190: Cooling device 200: Cooling water supply tank

300: control device

The present invention relates to a recirculation system for syngas cooling and washing waste water, and more particularly, to purify contaminants such as NH ₃ , H ₂ S, HCl, and COS contained in syngas with high purity, for fuel cell fuel or chemical raw materials. Syngas refining system to obtain ultra-clean syngas that can be used as a raw material for manufacturing. Synthetic gas cooling and washing water to purify and recycle the cooling and washing water used in the refining system to be reused as cooling and washing water. Relates to a recycling system.

Generally, when gas, such as coal, heavy residue oil, biomass, and waste, is gasified in a gasifier (gasifier), synthesis gas (exhaust gas, combustion gas) of high temperature and high pressure is generated and discharged. In order to convert such syngas into a fuel cell fuel or a raw material for producing a chemical fuel, contaminants in the syngas must be purified with high purity.

Specifically, the synthesis gas contains various trace impurities (pollutants) such as hydrogen sulfide (H ₂ S), hydrogen chloride (HCl), or COS, which are highly corrosive and exhibit corrosion and poisoning in catalysts for chemical fuel production. Therefore, these must be purified and removed.

In other words, the concentration of sulfur compounds that can be applied to a gas engine is known to be 20 ppm level, 1 ppm level when used as fuel of a fuel cell, and 1 ppm or less when used as a raw material for manufacturing chemical raw materials.

In this regard, conventional refining techniques include Korean Patent Application No. 10-2005-0091215 (Desulfurization Refining System for Coal Gasification Syngas) and Korean Patent Application No. 10-1987-0001305 (Removing hydrogen sulfide from polluted gas). Method), and Korean Patent Application No. 10-1994-0013701 (partial oxidation method for preparing purified hot gas) and the like.

On the other hand, in most of these refining techniques, the cooling washing waste water is generated during the cooling cleaning process.

However, there is a problem in that a large amount of wastewater is generated since the cooling and washing wastewater which has undergone the purification process is not reused in general, and in some cases, a polymer coagulant, a coagulant aid, caustic soda, etc. to treat particulate dust. The conventional wastewater treatment facility is composed of a chemical input facility for introducing wastewater, an equalization tank for equalizing wastewater, a chemical mixing tank for mixing with chemicals, a flocculation tank, a precipitation tank for precipitating aggregated particles, and a dewatering device for precipitated high concentration wastewater. Although it is commonly used for internal reuse, such a conventional wastewater treatment facility needs to be installed in a large capacity, thus requiring a lot of installation and operation costs, and a lot of facility sites for the wastewater treatment facility, and when treating wastewater to treat a large amount of cooling and washing wastewater. The amount of wastewater sludge which is the final by-product generated by adding chemicals There were a lot of problems that occurred.

In addition, when the existing wastewater filter system is used as a recirculation device for in-process reuse of the syngas cooling and washing wastewater, only particles of 3 to 5 μm or more are removed, which causes a problem of reprocessing particles of 3 to 5 μm or less. . In order to process the dust in the cooling washing waste water generated by the waste gasification cooling scrubber, it is stable to reuse it as cooling washing water only when dust particles larger than 0.5㎛ are treated. Therefore, the recycled water treated by the filter in the existing wastewater treatment device causes a problem in the nozzle of the waste gasification syngas cooling cleaner, causing problems in continuous operation.

The present invention has been devised to solve the above problems, by reducing the amount of use of the syngas cooling washing water by purifying the cooling washing wastewater generated from the cooling washing machine for the purification of the synthesis gas to recycle to the cooling washing machine. It is an object of the present invention to provide a recirculation system for syngas-cooled effluent wastewater which can reduce the amount of wastewater generated.

In addition, another object of the present invention is to provide a recirculation system for syngas cooling and washing waste water by allowing the cooling water to be recycled to pass through a cooling device to sufficiently perform a cooling role by maintaining the same temperature as the initial cooling washing water. The purpose is to provide.

In order to achieve the above object, the present invention provides a recirculation system for syngas cooling and cleaning wastewater, the filter comprising: a wastewater storage tank for storing the cooling and washing wastewater generated by the cooling and washing of the syngas, and a cooling and washing wastewater supplied from the wastewater storage tank. The backwashing device is provided with a plurality of backwash nozzles in the longitudinal direction from the upper side of the filtration filter such that the filtration filter is backwashed, and the cooling washing waste water washed through the backwashing device is washed with slurry. It provides a recirculation system for syngas cooling clean wastewater including a dewatering device for separating cooling water and a control device for controlling the backwashing device and the dewatering device so that a predetermined amount of cooling water can be recycled to the cooling water supply tank. .

In addition, the present invention is a method for recirculating the syngas cooling and washing waste water, the step of supplying the cooling and washing waste water to the backwashing device, in the backwashing device to measure the differential pressure of the filtration filter to stop the supply of the cooling and washing wastewater, and the filtration and backwashing process Recycling the syngas cooling wash wastewater comprising the step of proceeding, the dewatering step of separating the purified cooling wash waste water through the backwashing step into the slurry and the cooling water, and the recirculating cooling water separated in the dehydration step Provide a method.

The above objects and various advantages of the present invention will become more apparent from the preferred embodiments of the invention described below with reference to the accompanying drawings by those skilled in the art.

Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings.

1 is a block diagram showing a recirculation system of the syngas cooling washing wastewater according to a preferred embodiment of the present invention, Figure 2 is an enlarged view of the backwashing apparatus according to an embodiment of the present invention, Figure 3 is an embodiment of the present invention Flow chart of the method for recirculating the syngas cooling cleaning wastewater according to the present invention.

As shown in FIG. 1, the recycling system for syngas cooling and washing wastewater according to the present invention includes a wastewater storage tank 120 for storing the cooling and washing wastewater generated by the cooling and washing of the syngas, and a backwash for filtering the cooling and washing wastewater. A device 140, a dewatering device 170 for dewatering and separating the filtered cooling wash wastewater, and a control device 300 for controlling the backwashing device 140 and the dewatering device 170.

Here, a large amount of carbon particles are generated as dust in the synthesis gas in the process of producing syngas, which is fuel gas when gasifying from waste, and some of the incombustibles contained in the waste are generated as dust and are included in the synthesis gas. In order to purify the syngas into a fuel gas, the cooling cleaner 100 collects dust contained in the syngas and simultaneously cools the high temperature syngas to 75 ° C. or less.

Therefore, the present invention intends to recycle and reuse a large amount of cooling washing wastewater generated by the purification of syngas in the cooling washing machine 100, and the cooling washing waste water used from the cooling washing machine 100 is installed along the circulation line 110. Filled with waste water storage tank 120, the back of the waste water storage tank 120 is provided with a backwashing device 140 for purifying the cooling and washing waste water, between the waste water storage tank 120 and backwashing device 140 A wastewater supply pump 130 for supplying cooling washing wastewater is installed on the circulation line 110.

And the backwashing device 140, as shown in Figure 2, the case in which the inlet 141a communicating with the circulation line 110 is provided on one side is installed, the oil inlet (141a) inside the case 141 Cylindrical filtration filter 142 in communication with is installed in the form of a mesh. Preferably, the motor 143 is connected to one side of the case 141 to one side of the filtration filter 142 in order to rotate the filtration filter 142.

In addition, a plurality of backwash nozzles 144 are provided toward the filtration filter 142 along the length direction in the case 141 so as to backwash the filtration filter 142 on the upper side of the filtration filter 142. The backwash nozzle 144 is provided with a backwash feed pump 151 and a backwash storage tank 150 for supplying backwash water to the outer side of the case 141.

In addition, the lower surface of the case 141 is further configured to open and close the valve 145 in communication with the filtration filter 142, the non-reference numeral differential pressure gauge 146 is a flow meter, thermometer, filter to measure the flow rate supplied The differential pressure is measured.

In addition, the upper side of the backwashing device 140 is connected to the diatomaceous earth supply device 160 for supplying diatomaceous earth of 0.5㎛ particle to collect and remove the dust and the like contained in the cooling washing waste water.

And a dewatering device 170 for separating the cooling washing waste water washed through the backwashing device 140 into the slurry and the cooling water is installed on the lower side of the backwashing device 140.

Dewatering device 170 is a filter 171 is installed inside the cooling washing waste water passing through the filter 171 is separated from the slurry to be treated water, preferably the slurry hung on the filter 171 is not shown waste It is reintroduced into the gasification reactor.

The cooling water passed through the dehydration device 170 is recycled to the cooling water supply tank 200 using the dewatering pump 180, but is cooled between the dewatering device 170 and the cooling water supply tank 200. The device 190 is further included on the circulation line 110 to cool and supply the cooling treatment water.

On the other hand, the control device 300 is configured to control the backwashing device 140 and the dewatering device 170 so that a predetermined amount of cooling treatment water can be recycled to the cooling wash water supply tank.

The recirculation method of the syngas cooling and washing wastewater configured as described above is as follows.

Referring to FIG. 3, the method for recirculating the syngas cooling and washing wastewater includes supplying the cooling and washing wastewater to the backwashing device (400), and stopping the supply of the cooling and washing wastewater by measuring the differential pressure of the filtration filter in the backwashing device and filtering the wastewater. And a step 410 in which a backwashing process is performed, a dewatering step 420 of separating the purified washing water waste through the backwashing step into a slurry and a cooling water and a step of recycling the cooling water separated in the dewatering step ( 440, and more preferably, prior to the step of recirculating the cooling water separated by the dehydration step, a cooling step 430 for cooling the cooling water to a predetermined temperature is further included.

When the above steps are described in more detail, the cooling washing waste water used in the cooling cleaner 100 is introduced into the wastewater storage tank 120 along the circulation line 110, and the cooling washing wastewater filled in the wastewater storage tank 120 is wastewater. By the operation of the supply pump 130 is introduced into the cylindrical filtration filter 142 through the inlet 141a of the backwashing device 140, the case 141. At this time, the on-off valve 145 is closed, and when the differential pressure of the filtration filter 142 is 4 kg / cm 2 G by measuring the flow rate of the cooling washing waste water supplied from the differential pressure gauge 146, the control device 300 Will receive a signal to stop supplying wastewater.

In addition, the control device 300 proceeds with the backwashing process of the backwashing device 140 as the waste water supply is stopped. At this time, the opening / closing valve 145 is in an open state, and at the same time, the filtration filter 142 is a motor ( 143) to start the rotation.

In addition, the backwash water of the backwash water storage tank 150 is injected through the backwash nozzle 144 through the backwash supply pump 151 toward the rotating filtration filter 142. As a result, particles such as dust attached to the rotating filtration filter 142 are uniformly cleaned, and the filtration filter 142 assists in filtration of the cooling washing wastewater.

Furthermore, the diatomaceous earth supplied from the diatomaceous earth supply device 160 to the inside of the case 141 brings about an improvement in the filtration function due to the trapping action of dust or oil that is not easily filtered.

The cooling and washing waste water filtered and backwashed through the backwashing device 140 is introduced into the dewatering device 170 through the on / off valve 145.

The backwashing device 140 in which the backwashing is completed is supplied with cooling washing wastewater again.

The filter 171 installed inside the dewatering device 170 separates the slurry contained in the cooling wash waste water and the cooling wash water, and the separated slurry is mostly introduced into the waste gasification reactor with carbon particles and purified cooling. The washing water is introduced into the cooling device 190 by the operation of the dehydration pump 180 to undergo a cooling process.

This cools the cooling water, so that the cooling water can be sufficiently maintained to maintain the same temperature as the initial cooling water.

The cooled cooling water is introduced into the cooling water supply tank 200 and recycled to the cooling cleaner 100 for reuse.

The above process can be performed repeatedly and continuously by the control of the control device 300.

Therefore, unlike the prior art, the present invention does not use a complex wastewater treatment facility, and does not use a coagulant and a coagulant for agglomerating dust particles, thereby reducing the amount of sludge generated. In addition, since the prior art using the filtering method can remove about 3 to 5 μm, since the particles generated during the gasification of wastes contain a large amount of 0.5 to 3 μm particles, a secondary treatment device is required. There is an advantage to recycling.

In addition, since the cooling and washing waste water generated during the cooling and washing of the waste gasification syngas can be treated according to the present invention and reused as water in the cooling washing machine, the amount of water used can be saved. In addition, it is possible to build a zero discharge system by reusing the cooling clean waste water in the process, and by simply replacing the cooling clean waste water treatment device, the installation site can be reduced, and the installation cost and the operating cost can be reduced.

What has been described above is just one embodiment for implementing the recirculation system for syngas cooling clean wastewater according to the present invention, the present invention is not limited to the above embodiment, as claimed in the following claims Without departing from the gist of the present invention, anyone of ordinary skill in the art will have the technical spirit of the present invention to the extent that various modifications can be made.

According to the present invention, by recycling the cooling washing wastewater generated from the cooling cleaner for the purification of syngas to the cooling cleaner through the circulation device, the amount of the cooling gas used for the synthesis gas can be reduced and the amount of wastewater generated can be significantly reduced. It has an effect. In addition, it is also possible to sufficiently perform the cooling role by maintaining the same temperature as the initial cooling washing water by passing the cooling washing water recycled through the cooling device.

Claims (7)

As a recirculation system of syngas cooling wash wastewater, A wastewater storage tank for storing the cooling washing wastewater generated by the cooling washing of the synthesis gas; The case into which the cooling and washing waste water supplied from the waste water storage tank is introduced, a filtration filter installed in a cylindrical shape inside the case, a motor installed in the case so as to rotate the filtration filter, and the filtration filter is backwashed ( A backwashing device comprising a plurality of backwash nozzles provided along the longitudinal direction from the upper side of the filtration filter, and an on / off valve provided on the bottom surface of the case so as to be opened and closed in communication with the filtration filter; A dewatering device for separating the cooled washing wastewater passed through the backwashing device into a slurry and cooling water; A control device for controlling the backwashing device and the dewatering device so that a predetermined amount of the cooling treatment water can be recycled to a cooling wash water supply tank; Recirculation system of syngas cooling washing waste water comprising a. The method of claim 1, And a cooling device for cooling and supplying the cooling treated water between the dewatering device and the cooling wash water supply tank. delete The method of claim 1, And a diatomaceous earth supplying device for supplying diatomaceous earth to collect and remove dust and the like contained in the cooling washing wastewater. The method of claim 1, The backwash system further comprises a backwash water storage tank for supplying backwash water to the backwash nozzle. As a method of recycling the syngas cooling and washing waste water, Supplying the cooling washing waste water to a backwashing device; In the backwashing device, the differential pressure of the filtration filter is measured to stop the supply of the cooling washing wastewater, and the filtration and backwashing process is performed; A dewatering step of separating the cooling and washing waste water purified through the backwashing step into a slurry and cooling water; Recycling the cooling water separated by the dehydration step, Recirculation method of syngas cooling washing waste water containing. The method of claim 6, Before the step of recirculating the cooling water separated by the dehydration step, the method for recycling the syngas cooling washing waste water, characterized in that it further comprises a cooling step of cooling the cooling water to a predetermined temperature.

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