KR101284179B1 - Method for treating water treatment sludge - Google Patents

Abstract

PURPOSE: A purified sludge treating apparatus is provided to reduce a sludge by using dry air instead of heated air for saving the money of maintenance and predicting how much moisture will lose. CONSTITUTION: A purified sludge apparatus comprises the following steps. The purified sludge supplies dried air which is below 100°C to a drying tank filed with the purified sludge so that the purified sludge with high function is dried by the evaporation of the dried air. The dried purified sludge is plastic processed. In the drying step, an optimizing process is included in the drying tank. In the optimizing step, the curve of the purified sludge is calculated by calculating the weight change of the purified sludge in the drying tank and the flow rate of the dried air is controlled by the comparison between the set dried air curve and the calculated dried air curve. [Reference numerals] (AA) Sludge drying curve; (BB) Weight (Ton); (CC) Time (hr)

Description

Wastewater Sludge Treatment Method {METHOD FOR TREATING WATER TREATMENT SLUDGE}

The present invention relates to a water purification sludge treatment method.

In general, sludge is also called sludge (sludge) is a sediment produced during sewage treatment or water purification process is difficult to process because it contains more than 80% water.

Therefore, until now, the sludge was stabilized by anaerobic treatment, and then treated by a method of dehydration and landfilling. However, this treatment method has been a lot of research because the treatment is difficult due to the increase of the sludge according to the rapid industrial development.

In recent years, the sludge is heated inside the sludge by supplying high temperature hot air directly to the device that stores the sludge or by supplying high temperature heat to the sludge. The sludge drying apparatus is configured to minimize the weight and volume of the sludge and to lower the water content of the sludge by configuring to perform evaporation of moisture.

However, the conventional sludge drying apparatus is a heat drying method (rotary kiln, disk) to dry the moisture contained in the sludge by contact with hot air of 800 ℃ or more, due to the energy cost of marine discharge more than twice the discharge cost and the generation of exhaust gas such as NOx. There is a problem that a considerable budget should be spent on the facility cost for the post-treatment facility to prevent air pollution.

In addition, in the conventional sludge drying apparatus, even if the temperature of the drying apparatus is increased to increase the heat transfer rate in the heat drying of the sludge, since the outer sludge first absorbs all the heat energy and vaporizes the moisture into water vapor, the sludge inside the sludge is Heat transfer blockage occurs, which cuts off the supply of heat energy necessary for vaporization. Since the sludge is sequentially dried from the surface of the heat transfer blocking phenomenon, the heat energy required for drying is blocked.

As such, the conventional sludge drying apparatus has a problem that the drying rate and the drying speed are lower than the amount of heat applied.

In addition, sewage sludge is recycled a lot as agricultural organic raw materials, but since purified water sludge has less organic matter content than sewage sludge, it is practically difficult to use as an agricultural organic raw material such as fertilizer. For this reason, researches and attempts have been made to apply mainly to earthwork materials, ceramics, and soft materials by using inorganic components, which are the mains of purified sludge, and properties similar to clay in soil classification.

Purified sludge contains a large amount of inorganic material and has a property of hardening like a metal at 1000 ° C or higher. For this reason, when treated in the same manner as the general sewage sludge treatment method, after hard water sludge treatment, the hardened product should be ground through a separate grinding process. In addition, purified sludge has the characteristics of less odor and easy moisture content reduction than sewage sludge.

Conventional sludge treatment apparatuses have been designed and manufactured to treat both sewage sludge and purified sludge (or constant sludge) while neglecting the difference in the characteristics of purified sludge and sewage sludge. This causes an increase in the production cost of the sludge treatment apparatus and the addition of unnecessary unnecessary processes in treating the purified sludge, which greatly reduces the economics.

Embodiments of the present invention are to provide a water purification sludge treatment method that can reduce the sludge with low energy.

Embodiments of the present invention can be used to optimize sludge drying, and at the same time provide a sludge treatment method that can reduce the water content of the sludge within a very fast time, thereby reducing the energy waste consumed.

Embodiments of the present invention are to provide a water purification sludge treatment method that can dry the sludge using the amount of saturated steam of air.

The objects of the present invention are not limited thereto, and other objects not mentioned can be clearly understood by those skilled in the art from the following description.

According to one aspect of the invention, the drying step of drying the high water content sludge; And calcining the dry purified water sludge; The drying step may be provided with a purified water sludge treatment method for supplying dry air of less than 100 ℃ to the inner cylinder of the drying tank filled with purified water sludge to remove the water of the purified water sludge by the evaporation action by the dry air.

In addition, the drying step may further include the step of optimizing the evaporation action by the dry air in the drying tank.

In addition, the optimization step is to calculate the drying curve of the purified water sludge by measuring the weight change amount of the purified sludge filled in the drying tank, and compares the slope of the predetermined drying curve with the calculated slope of the drying curve to the drying tank The flow rate of the supplied dry air can be controlled.

In the drying step, when the temperature of the purified sludge filled in the drying tank is lower than a preset temperature, the drying tank may be preheated using waste heat generated during the calcining process of the purified sludge.

In addition, the purified sludge in the drying step may be maintained at a temperature of 90-99 ℃.

In addition, the drying step checks the temperature, humidity of the drying air supplied to the drying tank and the temperature, humidity of the drying air exiting from the drying tank, and compares this to calculate the amount of water escape from the purified sludge to the drying The flow rate of the drying air supplied to the tank can be controlled.

Embodiments of the present invention can reduce the operating cost because it does not boil, reducing the moisture content of the sludge only with dry air.

Embodiments of the present invention can utilize the waste heat to reduce the equipment operating cost.

Embodiments of the present invention can predict and adjust the target moisture release amount.

1 is a view showing a water sludge treatment apparatus according to an embodiment of the present invention.
2 is a graph showing the drying curve of the optimized sludge.

Hereinafter, with reference to the accompanying drawings will be described in detail the sludge treatment method according to a preferred embodiment of the present invention.

In the following description of the present invention, a detailed description of known functions and configurations incorporated herein will be omitted when it may make the subject matter of the present invention rather unclear.

1 is a view showing the water purification sludge treatment apparatus according to an embodiment of the present invention, Figure 2 is a graph showing the drying curve of the optimized sludge.

Referring to FIG. 1, the purified water sludge treatment apparatus 10 includes a drying unit 100, a conveying unit 200, and a baking unit 300.

The drying unit 100 is forcibly dried to a water content of 12 to 18% of the final high water content (70 ~ 80%) of the purified water sludge difficult to dry using dry air of less than 100 ℃. As an example, the drying unit 100 removes the water of the purified sludge using dry air of 90-99 ℃.

In the present invention, since the air temperature used for the sludge drying does not exceed 99 ° C., the existing drying device is a low consumption type drying device having a small amount of input energy compared to that of using a high temperature heat of 200 ° C. or more.

The drying unit 100 includes a drying tank 110, an air supply member 130, and a controller 140.

The drying tank 110 includes an inner cylinder 112 and an outer cylinder 116.

The inner cylinder 112 has an inner space 113 filled with purified sludge. The inner cylinder 112 is formed in a state in which an inlet for water purification sludge is opened on the upper side, the outlet 114 is provided on the lower side. The outlet 114 may be opened and closed by the opening and closing device 190. The discharge port 114 is connected to one end of the transfer unit 200, and the purified water sludge is dropped into the transfer unit 200 when the discharge port 114 is opened.

The inner cylinder 112 of the drying tank 110 is provided with a plurality of air injection means 192 connected with the pipe 122. The air injection means 192 includes injection nozzle tubes 194 in which a plurality of injection holes are formed so as to uniformly supply dry air to the purified sludge filled in the inner cylinder 112 of the drying tank 110. For example, the injection holes formed in the injection nozzle tube 194 may spray dry air downward so as not to be blocked by the purified sludge. The drying tank 110 injects dry air of less than 90-99 ° C. injected through the injection nozzle tubes 194 to dry the purified sludge by the relative humidity and the saturated vapor pressure difference.

The outer cylinder 116 is installed to surround the inner cylinder 112. A heat exchange space 118 is provided between the outer cylinder 116 and the inner cylinder 112 to which waste heat provided from the waste heat treatment unit 380 of the firing unit 300 is supplied.

The air supply member 120 heats the dry air so that the amount of saturated steam of the dry air is increased, and supplies the heated dry air to the drying tank 110. The air supply member 120 includes a heater 122 and a blower 124. The heater 122 may use various types of heaters, but may be, for example, a heater using an electrical resistance heating coil.

As such, the air supplied to the heater 122 through the blower 124 is heated to a temperature suitable for drying the purified water sludge and then supplied to the inner cylinder 112 of the drying tank 110. For example, the air may be heated to a temperature of 90-99 ° C or less. The air supply member 120 and the drying tank 110 are connected by the pipe 126, and the dry air discharged from the heater 122 is supplied to the drying tank 110 through the pipe 126.

The controller 130 controls the temperature and flow rate of the heated dry air supplied to the drying tank 110 to optimize the evaporation action of the dry air in the drying tank 110.

Meanwhile, the transfer unit 200 may be provided in the form of a screw conveyor in which the cylindrical casing 210 and the transfer screw 220 are coupled.

Cylindrical casing 210 is installed horizontally with the ground, one end of the cylindrical casing 210 is formed with a first opening in which the purified water sludge discharged from the discharge port 114 of the drying unit 100, the other end is purified A second opening through which sludge is discharged is formed, and the second opening is connected to the firing chamber 310 of the firing unit 300.

The feed screw 220 is installed inside the cylindrical casing 210 while maintaining the disk shape in the form of a screw. The conveying screw 220 is manufactured to be rotatable by a driving means such as a motor, and the conveying screw 220 has a circumference and a cylinder of a disc of the conveying screw 220 so that the purified water sludge can be conveyed to the second opening without missing. The spacing between the inner surfaces of the casing 210 is preferably made as narrow as possible.

The firing unit 300 includes a firing chamber 310, a cylindrical chamber 320, a firing heater 330, and a waste heat treatment unit 380.

The firing chamber 310 is provided with a cylindrical chamber 320 in which the transfer screw 324 is coupled. The transfer screw 324 may be provided on the inner surface of the cylindrical chamber 320. One end of the cylindrical chamber 320 is formed with a first opening through which the purified water sludge flows from the conveying part 200, and a second opening with a plastic treatment treated sludge is discharged at the other end.

Both ends of the cylindrical chamber 320 are rotatably supported by the support bearing 340, and the cylindrical chamber 320 is connected to the rotary drive 350 to rotate. The cylindrical chamber 320 may be made of a metal or alloy material having a high melting point higher than the firing temperature of the purified sludge. The firing temperature may be 500-1000 ° C. If the firing temperature is less than 500 ° C., there is a problem that firing does not occur sufficiently, and if the firing temperature is more than 1000 ° C., there is a problem that energy is wasted.

The firing heaters 330 are installed adjacent to the bottom of the cylindrical chamber 320. The firing heaters 330 may be electric furnace heaters.

The purified sludge introduced into the cylindrical chamber 320 is fired by the firing heaters 330 while passing through the cylindrical chamber 320 and then discharged to the yard 400.

The waste heat treatment unit 380 maintains the temperature of the drying tank using waste heat of the baking unit. Waste heat treatment unit 380 is connected to the firing chamber 310, the other end includes a waste heat supply line 382 is connected to the drying tank 110, the waste heat supply line 382 is provided with an on-off valve 384 is installed. .

Referring again to FIG. 1, the drying unit 100 includes a load cell 172, a sludge measuring unit 174, an air supply stage measuring unit 176, and an air discharge stage measuring unit 178.

The load cell 172 is installed to detect the change in weight of the purified water sludge filled in the inner cylinder 112 of the drying tank 110 in real time or every predetermined time. The load cell 172 provides the weight measurement value of the purified sludge to the controller 130.

The controller 130 calculates a drying curve of the purified sludge based on the weight change amount of the purified sludge provided from the load cell 172. Then, the temperature and flow rate of the drying air supplied to the drying tank 110 is controlled according to the slope of the drying curve.

2 shows the drying curve of the optimized sludge. As an example, the controller 130 compares the calculated slope of the drying curve with the predetermined slope of the preset drying curve (optimized drying curve), and if the slope is large, it is determined that the amount of drying is excessive compared to time and lowers the temperature of the drying air. Or reduce the flow rate to reduce excessive energy waste. In addition, when the slope is small, it is determined that the drying amount is insufficient for time, and the drying target amount may be adjusted by increasing the temperature of the drying air or increasing the flow rate.

On the other hand, the sludge measuring unit 174 checks the temperature and humidity of the purified sludge filled in the inner cylinder 112 of the drying tank and provides it to the controller 130.

The controller 130 controls the air supply member 120 and the waste heat treatment unit 380 to maintain the temperature of the purified sludge at 90-99 ° C. For example, the controller 130 increases the dry air temperature of the air supply member 120 or opens the waste heat treatment unit 380 when the temperature of the purified water sludge is checked to be lower than a preset temperature (for example, 95 ° C.). The waste heat is supplied to the heat exchange space 118 of the drying tank 110 to compensate for the temperature of the purified water sludge by auxiliaryly increasing the temperature of the inner cylinder 112. On the contrary, when the temperature of the purified sludge is checked to be higher than the preset temperature (for example, 95 ° C.), it is possible to lower the dry air temperature of the air supply member 120 or to block the waste heat supply to the heat exchange space 118. Reduce the temperature of the purified sludge.

The air supply stage measuring unit 176 checks the temperature and humidity of the dry air supplied to the drying tank 110, and the air discharge stage measuring unit 178 checks the temperature and humidity of the dry air flowing out of the drying tank 110. Check The temperature and humidity of the checked dry air are provided to the controller 130.

The controller 130 compares the dry air temperature and humidity of the air supply-side measuring unit 176 and the air discharge-side measuring unit 178 to calculate the amount of water escape from the purified sludge, and the air supply member ( Adjust the dry air flow rate of 120).

That is, the present invention calculates the amount of moisture evaporated from the purified sludge by the dry air based on the temperature and humidity of the air discharged from the drying tank 110, and if the required amount of drying, the flow rate, temperature, humidity of the supply and discharge Based on the control, the target moisture release amount can be predicted and adjusted.

Although not shown, the drying unit 100 may further include a dehumidifying means. The dehumidifying means is installed between the blower 124 of the air supply member 120 and the heater 122 to remove moisture in the air provided to the heater 122 and then provide it to the heater 122. The dehumidification means may be any structure commonly used in the art, and is not limited to any specific structure. For example, it may have a structure in the form of a porous pellet, and may be a structure that adsorbs the moisture particles of the air passing through the inner hole or the space to separate the air and the moisture.

The foregoing description is merely illustrative of the technical idea of the present invention, and various changes and modifications may be made by those skilled in the art without departing from the essential characteristics of the present invention. Therefore, the embodiments disclosed in the present invention are intended to illustrate rather than limit the scope of the present invention, and the scope of the technical idea of the present invention is not limited by these embodiments. The protection scope of the present invention should be interpreted by the following claims, and all technical ideas within the equivalent scope should be interpreted as being included in the scope of the present invention.

100: drying unit 200: transfer unit
300: firing unit

Claims (6)

delete delete In the water sludge treatment method:
A drying step of supplying dry air of 100 ° C. or lower to an inner cylinder of the drying tank filled with purified water sludge to dry the purified water sludge having a high water content by evaporation by the dry air; And
Calcining the dried water purified sludge;
The drying step
Optimizing the action of evaporation with dry air in the drying tank,
The optimization step
Flow rate of the dry air supplied to the drying tank by measuring the weight change of the purified water sludge filled in the drying tank to calculate the drying curve of the purified water sludge, comparing the slope of the predetermined drying curve with the calculated slope of the drying curve The sludge treatment method, characterized in that for controlling. The method of claim 3, wherein
The drying step
And when the temperature of the purified water sludge filled in the drying tank is lower than a preset temperature, preheating the drying tank using waste heat generated during the calcining process of the purified water sludge. The method of claim 4, wherein
In the drying step
The purified sludge treatment method is characterized in that the purified sludge is maintained at a temperature of 90-99 ℃. The method of claim 3, wherein
The drying step
The temperature and humidity of the drying air supplied to the drying tank and the temperature and humidity of the drying air exiting the drying tank are checked, and the amount of water escape from the purified water sludge is calculated by comparing them, and the drying air supplied to the drying tank. The sludge treatment method for controlling the flow rate of water.

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