KR20070068145A - Method for producing refuse-derived fuel using dye wastewater and powdered coke - Google Patents

Abstract

A method for producing a refuse-derived fuel using dyeing wastewater sludge and coke breeze is provided to produce a solid fuel by efficiently concentrating, dewatering and drying a mixture of coke breeze and dyeing wastewater sludge generated when treating dyeing wastewater. A method for producing a refuse-derived fuel using dyeing wastewater sludge and coke breeze comprises the steps of: flowing dyeing wastewater sludge settled in a settling tank(10) of a dyeing wastewater treating plant(40) into a mixing tank(20); agitating the mixture while injecting coke breeze and a cation polymer coagulant into the dyeing wastewater sludge flown into the mixing tank to form floc; flowing the floc-formed sludge into a concentration tank(30) to concentrate the sludge to a solid content of 3 to 5 wt.%; transferring supernatant in an upper part of the concentration tank to the dyeing wastewater treating plant, and storing concentrated sludge in a lower part of the concentration tank into a sludge hopper(50) below the concentration tank; and dewatering the sludge to a water content of 50 to 10% and drying the dewatered sludge after flowing the stored sludge into an electro-dewatering equipment(60) while pressing the sludge.

Description

Method for producing refuse-derived fuel using dye wastewater and powdered coke

1 is a schematic diagram showing a process for producing waste fuel according to the present invention.

Figure 2 is a schematic diagram showing the electric dewatering device of the present invention.

3 is a graph showing the calorific value change according to the powdered coke mixing ratio.

4 is a graph showing a calorific value according to moisture content.

<Description of Symbols for Major Parts of Drawings>

10: settling tank 20: mixing tank

21: flocculant storage tank 23: powder coke storage tank

25: stirrer 30: condenser

40: dyeing wastewater treatment plant 50: sludge hopper

51: pressure pump 60: electric dewatering device

The present invention relates to a method for manufacturing waste processed fuel using industrial waste, and more particularly, waste coke is mixed with dyed sludge generated in a dyeing wastewater treatment process, and wastewater having high calorific value through concentration, dehydration and drying. The present invention relates to a waste fuel manufacturing method using dyed sludge and powdered coke, which can be utilized as a processed fuel.

The dyeing industry uses dyes as a raw material to make colors appear through long-term physical and chemical reactions to the salts, resulting in color. Among the textile manufacturing industries that are one of the essential foods for human life. It is also the industry that emits the most pollutants.

Recently, in order to cope with international environmental regulations, the development of low-bath dyeing process by reducing water consumption in the dyeing process has been actively applied, resulting in relatively high alkali and high concentration of wastewater.

To ensure the quality of dyeing wastewater flowing into dyeing wastewater treatment, the results were collected samples of the dyeing wastewater flows into the joint wastewater treatment plant in the industrial complex dyeing wastewater of the largest D during the domestic investigation of water quality, BOD ₅ average 1387 mg / L, COD _Mn 658mg / L, SS 72mg / L, Chromaticity 965 (degree), TN 41.2mg / L, TP 6.51mg / L, n-Hexane 12.33mg / L and ABS 86.5mg / L .

As such, when treating the highly polluted dyeing wastewater, it is inevitable that the dyeing sludge which is highly polluted and generates a lot of odor is inevitable.

Incineration treatment can be considered as the optimal treatment method for such dyeing sludge. However, incineration generates a lot of greenhouse gases and harmful gases, and additional costs for the installation of incinerators and the treatment of harmful gases are required. At present, the treatment of dyed sludge depends mainly on dumping at sea.

However, due to the recent anticipation that it will be difficult to dump the ocean in accordance with international conventions, new treatment methods for dyeing sludge are urgently needed.

In order to solve the above problems, the dyeing sludge produced during dyeing wastewater treatment efficiently concentrated, dehydrated and dried to produce waste processed fuel using dyeing sludge and powdered coke for high calorific value solid fuel The purpose is to provide a method.

Waste treatment fuel manufacturing method using the dyeing sludge and powdered coke of the present invention for achieving the above object, the step of introducing the dyeing sludge precipitated in the settling tank 10 of the dyeing wastewater treatment plant into the mixing tank (20); A step of forming a floc by stirring while adding powdered coke and a cationic polymer coagulant to the dyeing sludge introduced into the mixing tank 20; Concentrating the floc formed sludge into the concentrating tank 30 so that the solid content is 3 to 5% by weight; The supernatant of the upper portion of the concentration tank 30 is transferred to the dye wastewater treatment plant, and the concentrated sludge under the concentration tank 30 is stored in the lower sludge hopper 50; And dehydration and drying so that the water content is 50 to 10% after flowing into the electric dehydration apparatus 60 while pressurizing the stored sludge.

At this time, the powdered coke is preferably added to 10 to 50% by weight based on the dyeing sludge, the cationic polymer coagulant is preferably added to 100 ~ 400ppm.

Hereinafter, with reference to the accompanying Figures 1 and 2 will be described in detail with respect to the present invention.

First, the dyeing sludge precipitated in the settling tank 10 of the dyeing wastewater treatment plant is introduced into the mixing tank 20 by using the transfer pump 11.

Next, the powdered coke stored in the powdered coke storage tank 23 is supplied to the mixing tank 20 using the pump 24, and the coagulant stored in the coagulant storage tank 21 is pumped to coagulate the dyeing sludge and the powdered coke mixture. The floc is formed by stirring the dyeing sludge, the powdered coke mixture, and the flocculant using the stirrer 25 while introducing the mixture into the mixing tank 20 using (22).

At this time, the blending ratio of the powdered coke to the dyed sludge is preferably 10 to 50% by weight. If the blending ratio is less than 10% by weight, there is almost no increase in calorific value, and if the amount exceeds 50% by weight, the throughput of the dyeing sludge is reduced, thereby reducing waste treatment efficiency.

As a result of analyzing the chemical composition of the dye sludge precipitated in the sedimentation tank of the wastewater treatment plant for the treatment of the dye wastewater, which was introduced into the co-drainage treatment plant of the satin wastewater of D city mentioned above, as shown in Table 1 below, Most of the organic matter and most of the inorganic iron was found to be.

Chemical Composition of Dyeing Sludge division Fe Al Cr Mn Si P Ca Ti Zn Sn Na K Mg Ig-loss weight% 15.06 0.16 0.025 0.024 1.18 0.77 0.77 0.59 0.020 0.30 0.86 0.085 0.071 68.86

According to the table, since most of the organic material in the dyeing sludge, it can be seen that by increasing the concentration of the cationic polymer coagulant in order to aggregate the organic matter. On the other hand, when looking at the inorganic composition of the dyeing sludge, iron is the majority of the inorganic composition, so when using the iron chloride as a flocculant, the calorific value of the dehydrated sludge is lowered, there is a problem that the chromaticity of the waste water treatment water is not preferable.

At this time, the amount of the cationic polymer coagulant is preferably 100 ~ 400ppm. If it is less than 100ppm, the aggregation does not occur, and if it exceeds 400ppm, the coagulation effect is lowered due to the excessive input of the flocculant and the clogging phenomenon of the filter cloth increases in the dehydration process.

Next, the dyeing sludge with floc formed in the mixing tank 20 and The powdered coke mixture is introduced into the concentration tank 30 and concentrated until the content of the solid content is lowered to a predetermined concentration.

The reason for the need for concentration of the dyeing sludge and the powdered coke mixture is as follows. The dyeing sludge infiltrated in the sedimentation tank of the dyeing wastewater treatment plant has a very low solids content of 0.5 to 0.8% by weight, which is transferred to the dehydration and drying apparatus. If so, it takes a long time for dehydration and drying, and a lot of filtrates are generated in the filtration process of the dyeing sludge as well as clogging of the filter cloth. Therefore, it can be seen that the more the dyeing sludge is concentrated prior to the dewatering and drying process for the dyeing sludge, the higher the yield of the processed waste fuel.

For example, if 100 tons of dyeing sludge with a solid content of 0.5% is transferred and completely dried, 0.5 tons of waste fuel is produced, but only 10 tons of sludge may be transferred when the dyeing sludge is concentrated to 5% by weight of solids. Therefore, effective concentration of dyeing sludge is essential.

Looking at the configuration of the thickening tank 30 for the concentration of the dyeing sludge and powdered coke mixture as described above, if the dyeing sludge in the mixing tank 20 is introduced into the inner thickening tube 31, the inner thickening tube 31 and the outer thickening tube Dyeing sludge is collected in (32) one by one, and the first and second sludges are concentrated.

At this time, it is preferable to concentrate the dyeing sludge so that the content of solids is 3 to 5% by weight, which means that when the solids content is less than 3% by weight, the effect of incorporation of the pretreatment facility is less than 5% by weight. This is because it takes a long time to concentrate the sludge.

Next, when the dyeing sludge and the powdered coke mixture is concentrated after a certain time, the supernatant of the upper portion of the concentration tank 30 is transferred to the dyeing wastewater treatment plant 40, and the dyeing sludge and the powdered coke concentrated under the concentration tank 30. The mixture is stored in the lower sludge hopper 50.

Finally, the dyeing sludge and the powdered coke mixture stored in the sludge hopper 50 is introduced into the electric dehydration apparatus 60 while being pressurized to 3 to 15 atm using a pressure pump 51 to dehydrate and dry.

Dehydration and drying by the electric dehydrator 60 will be described with reference to Figure 2, the concentrated dye sludge and the powdered coke mixture flows into the filter plate 63 through the sludge pipe 62 is installed on the support 61. On the other hand, when a DC current by the DC generator 65 is applied to the (+) and (-) electrode plates (not shown) inside the filter plate 63, the sludge particles of (-) charges move to the (+) electrode plate. Then, the water particles of (-) charge move to the (-) electrode plate. At this time, the DC current is applied to 30 ~ 120V, the temperature in the filter plate 63 is 50 ~ 100 ℃, the gas generated in the filter plate 63 was discharged using a vacuum pump (not shown).

 The sludge particles do not pass through the filter cloth (not shown) inside the filter plate 63, while the water particles pass through the filter plate 63 and are discharged into the filtrate discharge passage 64, thereby dehydrating and drying the dyeing sludge. You lose.

Dyeing sludge and bunkosk mixture dehydrated and dried through the above process can be used as fuel in incinerators or cogeneration plants.

Hereinafter, the present invention will be described through examples.

After collecting the dyeing sludge precipitated in the sedimentation tank of the satin wastewater treatment plant of D city described above into the mixing tank, 100 ~ 400ppm of cationic polymer coagulant was added while the amount of powdered coke to the dyeing sludge was 10 to 50% by weight. The floc was formed by stirring for 1 to 3 minutes while maintaining the speed of the stirrer 25 at 20-100 times / minute.

Then, after concentrating the solids content of the dyeing sludge and the powdered coke mixture in the concentration tank 30 to 3 to 5% by weight, the concentrated dyeing sludge is pressurized to 5 atm by the pressure pump 51 to the electric dehydration device ( 60), a direct current was applied at 30 to 120 V, and the temperature in the filter plate 63 was heated to 50 to 100 ° C.

At this time, as a result of measuring the calorific value of the dyeing sludge according to the blended coke ratio, as shown in the graph of FIG. It can be seen that the compounding ratio does not exceed 50% by weight as the throughput of the dyeing sludge decreases.

On the other hand, the result of measuring the calorific value according to the water content of the dyeing sludge is shown in FIG. According to the graph of FIG. 4, the longer the drying time, the lower the moisture content of the dyeing sludge and the higher the calorific value. However, it is reasonable to consider that the moisture content is 50 to 10% in consideration of the electrical energy consumption required for drying.

According to the waste fuel manufacturing method using the dyeing sludge and powdered coke of the present invention configured as described above, by reducing the amount of sludge conveyed by concentrating the dyeing sludge, the treatment cost of the dyeing sludge can be greatly reduced, and the dyeing sludge and powdered coke mixture By dehydration and drying at an appropriate moisture content, there is an effect that can produce a waste water processed fuel having a maximum calorific value relative to the treatment cost.

Claims (3)

Introducing the dyeing sludge precipitated in the settling tank 10 of the dyeing wastewater treatment plant into the mixing tank 20; A step of forming a floc by stirring while adding powdered coke and a cationic polymer coagulant to the dyeing sludge introduced into the mixing tank 20; Concentrating the floc formed sludge into the concentrating tank 30 so that the solid content is 3 to 5% by weight; The supernatant of the upper portion of the concentration tank 30 is transferred to the dye wastewater treatment plant, and the concentrated sludge under the concentration tank 30 is stored in the lower sludge hopper 50; And Dehydration and drying so that the moisture content is 50 ~ 10% after flowing into the electric dehydration device 60 while pressing the stored sludge Waste processed fuel manufacturing method using the dyeing sludge and powdered coke characterized in that comprising a. The method of claim 1, The powdered coke is a waste fuel manufacturing method using the dyeing sludge and powdered coke, characterized in that 10 to 50% by weight based on the dyeing sludge. The method of claim 1, Waste treatment fuel production method using a dyeing sludge and powdered coke, characterized in that the cationic polymer coagulant is added to 100 ~ 400ppm.

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