KR101999637B1 - Hybrid Sludge Fuel, Manufacturing Method and System of Fuel Production thereof - Google Patents

Abstract

The present invention relates to a hybrid sludge fuel coal production system and a method for manufacturing the same, which can greatly contribute to foreign currency saving by making RPS (mandatory use of renewable energy for reducing carbon dioxide) for high-calorie power plants to replace wood pellet fuel which is previously dependent on imports entirely, through environmentally friendly treatment of sewage sludge, which is a malignant waste, such as groundwater pollution caused by the generation of a large amount of leachate. Compared with the conventional solid fuel production system utilizing sewage sludge, there is an effect of reducing the energy requirement and enabling the supply of solid fuel having a high calorific value.

Description

RPS-compatible fuel coal production system for power plant using dried sewage sludge and manufacturing method thereof {Hybrid Sludge Fuel, Manufacturing Method and System of Fuel Production}

The present invention relates to an RPS-compatible fuel coal production system for a power plant using dried sewage sludge and a method for manufacturing the same, and more specifically, environmentally friendly high-calorie sewage sludge, which is a malignant waste that causes groundwater contamination by generating a large amount of leachate, is produced. It uses dry sewage sludge that can make a significant contribution to foreign currency savings by making it a fuel for RPS (mandatory use of renewable energy to reduce carbon dioxide) for power plants. An RPS-compatible fuel coal production system for a power plant and a method of manufacturing the same.

Fossil fuels have been pointed out as a less competitive energy source for global warming due to their high carbon dioxide emissions. In this regard, as an energy source capable of coping with global warming and climate change, the use and dissemination of renewable energy in which carbon dioxide emissions are reduced compared to conventional fossil fuels such as petroleum and coal are being issued worldwide.

With the depletion of fossil fuels and the reduction of greenhouse gases in response to the international agreement on climate change, the total amount of power generated by power generation companies (duties of supply mandates) with power generation facilities (excluding renewable energy facilities) of more than 500MW. The Renewable Portfolio Standard (RPS) was introduced, which mandates the supply of more than a certain percentage of renewable energy. In addition, the law has been enacted to impose penalties within 150% of the average transaction price of supply certificates, taking into account the reasons for non-compliance and the number of non-compliance.

Renewable Energy Certificate (REC) is a certificate proving that the electricity generation company has produced and supplied electricity by using renewable energy facilities. The RPS system's supply manger purchases the renewable energy supply certificate. Must meet the quota.

The weight of each renewable energy source is reviewed by the government and reviewed every three years in consideration of the effects on the environment, technology development and industrial activation, power generation costs, potential losses, and greenhouse gas emission reduction.

As a result, large coal-fired power plants are linked with power plants to reduce CO2 emissions from coal to achieve this new renewable energy supply ratio.In addition, integrated gasification combined cycle (IGCC) and ultra-supercritical systems are proposed. Clean Coal Technology (CCT) such as Ultra Supercritical (USC) Technology, CO ₂ Capture and Storage Technology, Bio-mass, Solid Refuse Fuel (SRF), Waste Plastic Solids While attempting to introduce fuel (Refuse Plastic Fuel, RPF), etc., there are many areas that need to be improved to solve fundamental problems.

On the other hand, the amount of food waste generated in Korea is about 11,798 tons (as of 2012), accounting for about 26.5% of total solid waste, which causes food waste to collect, transport, and landfill. It causes various environmental problems such as occurrence.

In addition, since the amount of sludge also increases as the amount of sewage treatment increases rapidly, treating the slurry is also a serious problem. In particular, the Basel Convention, which prohibits the discharge of hazardous wastes from the ocean, has caused further problems in the treatment of food waste and sewage sludge.

In this regard, the sewage sludge treatment methods in Gyeonggi-do before the ban were 35% incineration, 32% offshore discharge, 21% fueled and recycled, and 12% landfilled. The cost of incineration and landfill is also increasing, and there are many difficulties in disposal due to the lack of treatment facilities in the metropolitan landfill.

In addition, most of the sewage sludge produced in sewage treatment plant is treated as a private consignment after dehydration stage, which contains some moisture. As the consignment rate increases by more than 10%, the treatment cost increases, resulting in a conflict on environmental costs. It is happening. Sewage sludge generated in sewage treatment plants generally has a water content of 77% to 82% depending on the treatment method and the dehydration method, and landfill and incineration treatment methods are used to collect sewage sludge.

Solid fuel development research using the sewage sludge and food waste has been continued, but there is a problem that power generation efficiency is lowered because the calorific value of biomass is relatively low. Therefore, it is a time when the development of manufacturing technology for the high calorific value solid fuel required by the power plant is urgently needed.

On the other hand look at a number of known documents to address the above problems are as follows.

Korean Patent Publication No. 2002-0015759 (2002.03.02) discloses sewage / wastewater sludge cakes and organic food wastes generated during sewage treatment, and food wastes of high calorie content (waste tires, waste vinyl, waste foamed polystyrene, Waste PET, waste HDPE, etc.) into a predetermined ratio, crushing and mixing with a mixer feeder; A second step of introducing the mixed sludge cake, food waste dried matter, and combustible waste powder into a molding machine and solidifying the same into a predetermined size; A third step of drying the molded product in a dryer supplied with hot air generated from the combustion means; A fourth step of introducing a predetermined amount of dried solid fuel into the combustion means; Disclosed is a method for producing a solid fuel, characterized in that sequentially connected. However, there is a disadvantage in that the high calorific value of combustible waste mixed during the process and the drying operation cost are high.

In Korean Registered Patent No. 0162130 (1999.01.15), various wastes stored in a waste storage bin are classified into combustible waste and non-combustible waste, and only the combustible waste that can be used is selected and transferred through a transfer conveyor. After the crushing process over the third and third stages, the crushed waste is gradually divided into three lines, and the crushed waste is divided into three lines by the first distribution, and then dried by using the waste heat of the incinerator to achieve complete drying. The wastes are sprayed with additives, which are gas and odor neutralizers, to form primary solid fuel masses by applying primary pressure and high temperature heat, and the solid fuel masses are distributed to both sides in the second distribution. Evenly distributed and then completely molded over the 2nd and 3rd stages to produce a finished solid fuel mass. And it discloses a method of manufacturing a box for solid fuel with waste, characterized by for use as a fuel for industrial applications. However, the calorific value of the solid fuel produced by the above technology does not reach the calorie level required by the power plant, and has a disadvantage of high drying cost.

In Korean Patent Publication No. 2007-0076557 (July 24, 2007), the process of drying and grinding the sewage sludge to 10-20% or less of water content, and food waste 70% (weight ratio) to loess 10% (weight ratio); Lignite 10% (weight ratio): mixing with coke 10% (weight ratio) additives, grinding combustible waste to a particle size of 30 ~ 50mm, dried sewage sludge, food waste mixed with additives, grinding Mixing the combustible wastes into sewage sludge 30% (weight ratio): food waste 30% (weight ratio): combustible waste 40% (weight ratio), drying the mixture so that the water content is 10% or less, Disclosed is a method for producing a solid fuel using sewage sludge, food waste, and combustible waste, comprising the step of adding a supporting material to a mixture made of mixing and drying, and extruding and molding to a predetermined size. However, there is a drawback of increasing the cost of producing a solid fuel due to the supply of lignite and coke input to satisfy the calorific value and drying conditions of the solid fuel.

Korean Laid-Open Patent Publication No. 2002-0059074 (2002.07.12) includes the steps of separately composing each combustible waste in fueling combustible waste such as household waste, food waste, vinyl, plastic, sludge, etc .; Drying the combustible wastes crushed by the crushing process through a drying apparatus; Mixing combustible wastes dried by the drying step in an appropriate ratio according to a desired amount of heat; Hot pressing the mixed mixture into a solid fuel having a shape having the best combustion efficiency; Disclosed is a combustible waste fuelization method comprising a process of cooling and packaging a solid fuel that is hot-pressed by a molding process. However, there are disadvantages in that the efficiency of the drying process is lowered and the process cost of the high temperature compression process is high.

Therefore, to promote the use and dissemination of renewable energy, to ensure the safety of sewage sludge and waste disposal operations, and to produce RPS-compatible fuel coal for power plants using dried sewage sludge to effectively replace wood pellet fuel, which previously relies on imports. There is an urgent need for technical development of the system and its manufacturing method.

Korean Laid-Open Patent Publication No. 2002-0015759 (2002.03.02) Korean Registered Patent Publication No. 0162130 (1999.01.15) Korean Laid-Open Patent Publication No. 2007-0076557 (2007.07.24) Korean Laid-Open Patent Publication No. 2002-0059074 (2002.07.12)

The present invention has been made in order to solve the above problems, the environmentally friendly treatment of sewage sludge, which is a malignant waste, such as groundwater contamination caused by the generation of a large amount of leachate through environmentally friendly RPS (renewable energy for reducing carbon dioxide) Mandatory use) Providing RPS-compatible fuel coal production system for power plants using dried sewage sludge that can greatly contribute to foreign currency saving by replacing wood pellet fuel, which has been relying on total imports, by making corresponding fuel. There is.

The present invention for achieving the above object is an RPS-compatible fuel coal production system for a power plant using dried sewage sludge, a mixing unit for mixing the calorific enhancer with the sewage sludge to produce a mixture, the mixture is extrusion molded into cylindrical pellets It may include a molding unit, and a drying unit for drying the pellets.

In addition, the mixing unit may include a first moisture content meter for measuring the moisture of the mixture.

In addition, a steam supply device is positioned between the mixing unit and the molding unit, and the steam supply device may supply steam such that the water content of the mixture is 15% to 21%.

In addition, the drying unit may be dried by irradiation of hot air or microwave to reduce the water content of the pellet 5% to 15%.

In addition, the hybrid sludge fuel coal production system, a cooling unit for cooling the pellets heated in the drying unit, a second moisture content meter for measuring the moisture content of the cooled pellets, and the pellets to be stored in a state of blocked water A storage unit may be further included.

In addition, the hybrid sludge fuel coal is produced using the production system, the low calorific value may be a hybrid sludge fuel coal larger than 3,500 kcal / kg, specifically, may be a hybrid sludge fuel coal larger than 4,000 kcal / kg.

In addition, the hybrid sludge fuel coal may include 1 wt% or less of sulfur.

In addition, the hybrid sludge fuel coal may include 50% by weight or less of volatile content.

In addition, the production method of the hybrid sludge fuel coal may be a production method of the hybrid sludge fuel coal including the following steps.

(a) mixing sewage sludge and a calorific enhancer;

(b) extruding the mixture mixed in step (a) into cylindrical pellets; And

(c) drying the pellets

In addition, step (a) may include a first moisture content measuring step (a-1) of measuring the water content of the mixed mixture.

In addition, the water content of the mixture may further include a step (b-1) of supplying steam before the step (b) so that the water content of 15% to 21%.

In addition, the hybrid sludge fuel coal production method further includes (d) drying the dried pellets in step (c), and (e) cooling the heat-dried pellets in step (d). In addition, the step (e) may include a second moisture content measuring step (e-1) of measuring the moisture content of the cooled pellets.

In addition, the step (c) may be a step of irradiating hot air or microwave to reduce the water content of the pellet 5% to 15%.

In addition, the steps of (c) to (e-1) may be repeatedly performed so that the water content range measured in step (e-1) is 10% or less.

According to the RPS-compatible fuel coal production system for a power plant using the dried sewage sludge of the present invention and a method of manufacturing the same, an energy requirement is reduced as compared with the conventional solid fuel production system using the sewage sludge.

In addition, there is an effect of enabling the supply of a solid fuel having a high calorific value.

1 is a process diagram showing a hybrid sludge fuel coal production system according to an embodiment of the present invention.
Figure 2 is a photograph of the moisture calorific value regulator supply hopper for supplying the mixing unit of the hybrid sludge fuel coal production system according to an embodiment of the present invention.
Figure 3 is a twin paddle mixer picture of the mixing unit of the hybrid sludge fuel coal production system according to an embodiment of the present invention.
Figure 4 is a picture of the molding unit of the hybrid sludge fuel coal production system according to an embodiment of the present invention.
5 is a picture of the fuel produced in the hybrid sludge fuel coal production system according to an embodiment of the present invention.
6 is a photograph of a multi-stage paddle drying unit in which microwaves are installed in a hybrid sludge fuel coal production system according to an embodiment of the present invention.
7 is a photograph of a device of an exhaust gas treatment unit of a hybrid sludge fuel coal production system according to an embodiment of the present invention.
8 is a photograph of a closed storage tank constituting unit of the hybrid sludge fuel coal production system according to an embodiment of the present invention.
9 is a TGA analysis result for confirming the combustion characteristics of the molded fuel produced in the hybrid sludge fuel coal production system according to an embodiment of the present invention.

The terms or words used in this specification and claims are not to be construed as limiting in their usual or dictionary meanings, and the inventors may appropriately define the concept of terms in order to best explain their invention in the best way possible. It should be interpreted as meaning and concept corresponding to the technical idea of the present invention based on the principle that the present invention. Therefore, the embodiments described in the present specification are merely exemplary embodiments of the present invention and do not represent all of the technical ideas of the present invention, and thus, various equivalents and modifications may be substituted for them at the time of the present application. It should be understood that it can.

Hereinafter, a complex fuel production system using sewage sludge according to the present invention will be described in detail with reference to the accompanying drawings.

1 is a process diagram showing a hybrid sludge fuel coal production system according to an embodiment of the present invention.

1, a hybrid sludge fuel coal production system using sewage sludge according to the present invention includes a mixing unit 100 for mixing a calorific enhancer with the sewage sludge to generate a mixture; It consists of a structure comprising a molding unit 200 for extruding the mixture into a cylindrical pellet and a drying unit 300 for drying the mixture.

The sewage sludge stored in the sewage sludge storage tank 10 and the caloric enhancer stored in the caloric enhancer storage tank 11 are moved to the mixing unit 100 and mixed.

Specifically, FIG. 1 illustrates a structure in which the sewage sludge and the calorific enhancer are met before being supplied to the mixing unit 100 and supplied to the mixing unit 100, but the present invention is a sewage sludge storage tank 10 and a calorific reinforcement storage tank. (11) comprises a structure in which each is made in communication with the mixing unit 100 so that the sewage sludge and the calorific enhancer are mixed after being supplied to the mixing unit 100.

The sewage sludge before mixing with the caloric reinforcement may be supplied with sewage sludge in a dried state, or may be supplied with sewage sludge in a dry state.

When sewage sludge is supplied before drying, the sewage sludge may be subjected to at least one drying process selected from the group consisting of electric dehydration, microwaves, light waves, hot air, and steam.

When the drying process is composed of two or more kinds, a sequential drying process may be performed, or two or more kinds of drying processes may be performed at the same time.

The mixing unit 100 is provided with a first moisture content measuring instrument 110 for measuring the moisture of the mixture, for example, when the sewage sludge is supplied in a dried state, the first water content measuring instrument 110. If the moisture content of the mixture measured in the lower than 15% to 21% of the water content range suitable for extrusion molding using the molding unit 200, the steam supply located between the mixing unit 100 and the molding unit 200 Steam may be supplied from the device 120. Alternatively, in the case of supplying sewage sludge in an undried or semi-dry state, when the moisture content of the mixture measured in the first water content measuring instrument 110 is higher than 15% to 21%, a drying unit is additionally added to the mixing unit 100. The drying of the mixture can be achieved.

The drying unit may be operated in a positive pressure state therein. The positive pressure condition is not limited to any condition as long as it can prevent the external oxidant from flowing into the drying unit. The positive pressure may be 0.01 atm to 10 atm. Preferably from 0.05 atm to 5 atm, more preferably from 0.05 atm to 1 atm. Outside the above conditions, the effective positive pressure of the drying unit cannot be maintained.

Optionally, the cooling unit 400 may be positioned at the rear end of the drying unit 300, and the water content of the cooled pellet may be measured while the second water content measuring unit 420 is positioned at the cooling unit 400. The cooling unit 400 may store the pellets in a state of being blocked with external air without supplying cold air, and may constantly measure whether the moisture content of the pellets stored in the drying unit 300 is outside a predetermined range. .

The cooling unit is cooled to prevent the ignition of the fuel coal discharged through the carbonization unit, so long as the ignition can be prevented. Cooling temperature of the fuel coal may be 1 ℃ to 20 ℃. Outside the above conditions, no effective cooling is achieved.

In addition, at the rear end of the cooling unit 400, the storage unit 500 may be located, and the pellet may be stored in a state in which it is blocked from outside air so that the moisture content of the pellet can be maintained.

2 is a photograph of a moisture calorific value regulator supply hopper which is a kind of calorific enhancer for supplying a mixing unit of a hybrid sludge fuel coal production system according to an embodiment of the present invention.

In general, the calorific enhancer may be any one or two or more of wood (waste) sawdust, waste tires, waste vinyl, waste foamed polystyrene, waste PET, waste HDPE, dried food waste, herbal or woody biomass. Specifically, it may be dried food waste and sawdust, and more specifically, may be sawdust.

The caloric enhancer is used as a calorific supplement for the purpose of adjusting the moisture of sewage sludge which is the main raw material and sewage sludge. The calorie enhancer may be supplied in the form of a bulk bag, and the bulk bag may be transferred to the upper portion of the calorific enhancer hopper for supply by a hoist installed in the building and supplied to the hopper.

The calorific reinforcing hopper has an inlet in which a bulk bag can be placed, and the periphery of the inlet is manufactured in the form of a round cone so that no gap occurs between the hopper and the bulk bag. The lower portion of the hopper is provided with a screw feeder for quantitative supply, the screw feeder is equipped with an inverter for adjusting the rotational speed to adjust the supply amount by the speed adjustment.

Figure 3 is a twin paddle mixer picture of the mixing unit of the hybrid sludge fuel coal production system according to an embodiment of the present invention.

Referring to FIG. 3, the mixing unit is not limited in form if it can effectively mix the sewage sludge and the calorific enhancer, but in detail, may be a twin paddle type mixer for continuous mixing. .

In the twin paddle mixer, the sewage sludge and caloric enhancer (sawdust, food waste drying product) may be mixed in a ratio of 4: 6 to 9: 1, or in detail, in a ratio of 5: 5 to 7: 3, The paddles arranged along the two axes can be rotated in opposite directions, respectively, and can be designed to be mixed while the sewage sludge and calorific enhancer are introduced from one side and transported in the other direction for continuous mixing. For example, juicy sewage sludge is first introduced and sawdust and food waste dry matter are added thereon and mixed with each other by rotation of the paddle.

In the twin paddle mixer, the rotational speeds of the paddles may be the same or may be configured to have different rotational speeds, for example, assuming that the rotational speed of any one paddle is one. The rotational speed of the other paddle may be 1 to 3.

The twin paddle type mixer may be a shaftless mixer. The sewage sludge and the calorific enhancer may be simultaneously introduced into the twin paddle type mixer or specific components may be sequentially added. In detail, sewage sludge containing excess moisture may be added first, and then caloric enhancers may be added thereto. Deviation from the above conditions may result in no effective mixing. The paddle may be formed in any one or two or more forms of a triangle, a square, a pentagon, a hexagon, a circle, and an irregular shape. The paddle spacing may have an equal spacing or a gap between paddles of a predetermined ratio. In detail, the paddles may be formed at equal intervals.

The water content of the mixture of the sewage sludge and the calorific enhancer may be related to the type and material of the mixer of the mixing unit. Therefore, it is necessary to adjust the moisture content of the mixture so that it is attached to the inner wall of the mixer so that the mixing efficiency is not lowered. . Thus, a unit for additionally supplying moisture to the mixing unit or vice versa may be further applied.

In general, since the sewage sludge itself has a low calorific value, when only sewage sludge is used as fuel coal, it is difficult to meet the calorific value standard set by the GR standard.

Therefore, the present invention is used in the form of a mixture of sewage sludge and caloric enhancer.

The mixing ratio of the sewage sludge and calorific reinforcing agent is, for example, the input conditions of dried food waste to sawdust with respect to 7 parts by weight of the sewage sludge may be 1 part by weight: 2 parts by weight to 1.5 parts by weight: 1.5 parts by weight, Alternatively, the sawdust may be included in 3 parts by weight based on 7 parts by weight of the sewage sludge. When the mixing ratio of the sewage sludge and the calorific reinforcing agent is out of the above conditions, the efficient heating and calorific value of the final solid fuel are lowered.

On the other hand, the GR standard is limited by limiting the ratio of the calorific enhancer, the calorific value of the mixture can meet the GR standard, the calorific value of the sewage sludge may be 2,500 kcal / kg to 6,000 kcal / kg In detail, it may be from 3,000 kcal / kg to 6,000 kcal / kg.

Therefore, before the mixture is prepared, a unit for measuring the calorific value of the sewage sludge may be further included, and the type and content ratio of the sewage sludge mixed with the calorific enhancer may be determined according to the calorific value measured in the calorific value measuring unit. Alternatively, in order to increase the calorific value of the fuel coal manufactured from sewage sludge, a process of carbonizing before or after the forming step may be added.

In addition, the method for producing a hybrid sludge fuel coal according to the present invention is applicable to the case of producing a hybrid sludge fuel coal using sewage sludge containing more than 1% by weight of sulfur, the hybrid sludge produced according to the present invention Sulfur content of the fuel coal is included in less than 1% by weight. On the other hand, the GR specification is limited to limit the sulfur content, the hybrid sludge fuel coal according to the present invention has a sulfur content condition that can meet the GR specification.

Figure 4 is a picture of the molding unit of the hybrid sludge fuel coal production system according to an embodiment of the present invention.

The molding process is a process of molding into a pellet shape by applying a high pressure to a raw material containing a specific range of moisture, and the molding unit may be a pressure pellet molding apparatus. In detail, the molding apparatus may use a vertical type pelletizer or a horizontal type pelletizer, and may also use a ready-made molding apparatus. However, the die of the molding apparatus is manufactured in a special shape to match the sewage sludge characteristics.

5 is a picture of the fuel produced in the hybrid sludge fuel coal production system according to an embodiment of the present invention. Referring to FIG. 5, the pellet-type hybrid sludge fuel coal may have a relatively small diameter and a long cylindrical shape.

The diameter of the pellet may be in detail 2mm to 20mm, more specifically 6mm to 10mm. Outside the diameter condition, the solid fuel utilization may be lowered.

The length of the pellet may be in detail 10mm to 100mm, more specifically 20mm to 50mm. Outside the above length condition, the solid fuel availability may be lowered.

6 is a photograph of a multi-stage paddle drying unit in which microwaves are installed in a hybrid sludge fuel coal production system according to an embodiment of the present invention.

Referring to FIG. 6, the multi-stage paddle drying unit may be installed in multiple stages of two to ten stages, and more specifically, three to five stage paddles may be installed. If it is not formed in the singular, it is difficult to achieve sufficient drying efficiency. The multi-stage paddle may be a paddle screw, the inner casing formed paddle screw may be dried while transporting the mixture.

Specifically, the drying unit may be a paddle screw casing for the transfer and drying of the raw material as an inner case and may be configured as an outer case made of a double jacket form surrounding the inner case. The outer case transfers the raw material to the inner case and supplies hot dry indirect hot air from the energy supply unit, and the indirect hot air is transferred to the paddle screw casing to heat and dry the raw material in the inner case.

Since the drying of the mixture by the indirect hot air only needs to remove steam generated therein, the amount of exhaust gas may be relatively lower than that of the direct hot air drying method. In addition, the generated exhaust gas can be sent to the energy supply unit for combustion. At this time, the odor component contained in the exhaust gas can also be incinerated and removed.

Therefore, it is possible to reduce the drying energy by 20% or more as compared to the general hot air dryer such as shortening drying time by using microwave and reducing exhaust energy by reducing exhaust gas.

Microwave generators may be installed at each stage inlet of the multistage portion of the drying unit. The capacity of the microwave generator may be 0.1kwh to 5kwh, in detail may be 0.5kwh to 3kwh and more specifically 1kwh to 2kwh. Outside the above dose range, the internal water of sewage sludge cells cannot be effectively dried. Moisture of the mixture passed through the drying unit may be 10% to 20%. In order to extrude the mixture of sewage sludge and sawdust into pellets, the moisture of the mixture should be maintained at about 18%.

Organic sewage sludge is mainly composed of organic matters (microorganisms, etc.). Among the organic matters, there are organic matters having cell walls, and water is filled inside the cell walls. Since the moisture inside the cell wall can evaporate only when the cell wall is destroyed, general hot air drying takes a long time. The microwave is a high frequency (1.9 GHz or 2.4 GHz, 915 MHz or 2,450Mhz) by applying a natural vibration to promote the vibration of the water molecules, bar water molecules inside the cell wall to generate heat.

As such, when the temperature of the water molecule increases and phase changes to water vapor, the pressure inside the cell wall is increased to destroy the cell wall. Therefore, in the case of using microwaves, the cell walls can be destroyed within a short time and rapid drying can be achieved by vibration and collision of water molecules.

In order to dry the product after pellet molding to 10% or less of residual moisture, the amount of drying may be controlled according to the measured amount of moisture.

As such, the drying unit may be dried by hot air or microwave irradiation in order to reduce the water content of the pellets by 5% to 15%.

7 is a photograph of a device of an exhaust gas treatment unit of a hybrid sludge fuel coal production system according to an embodiment of the present invention.

In general, water vapor containing the odor discharged from the dryer is sent to the combustion furnace and is reburned in direct contact with the flame generated by the combustion burner of the furnace. The burned hot gas is sent to a jacket surrounding the outside of the dryer for use in drying, and the gas used for drying is discharged into the atmosphere through an exhaust gas treatment device.

Exhaust gas contains a small amount of fines (combustion material) generated in a dryer and burned in a combustion furnace, and also contains gaseous substances in which odor is burned. The exhaust gas is first subjected to a cyclone to remove fine powder, and water vapor is recovered by cooling with water through a cooling device. The exhaust gas from which water has been removed is adsorbed through the activated carbon adsorption column to adsorb gaseous substances and then discharged into the atmosphere by an exhaust fan.

8 is a photograph of a sealed storage constituting unit of the hybrid sludge fuel coal production system according to an embodiment of the present invention.

In general, it is desirable to store sewage sludge which has a high water content and a risk of odor generation in a sealed reservoir, and a fixed amount of sewage sludge stored in the sealed reservoir can be supplied quantitatively when supplied to a system for fuel supply. have. Thus, a fully sealed storage tank is manufactured by using an iron plate, and an upper and lower type automatic door device is installed at the top to allow sludge to be introduced into a dump truck.

In addition, the closed reservoir is opened only during the input and closed again after the input so that the odor inside does not escape to the outside. An exhaust nozzle is installed at the upper part of the hermetic storage tank, and an odor reduction device capable of processing the odor emitted and a negative pressure applied to the inside of the storage tank to prevent internal air (including odor) from escaping to the outside and Connected. Discharge device connected to the next process by discharging a predetermined amount of sewage sludge in the bottom of the hermetic storage tank, a fixed amount supply device may be formed in the lower portion, the fixed amount supply device is limited to the form if the sewage sludge can be quantitatively supplied It is self-evident. The metering feeder may be specifically configured as a twin screw conveyor and a twin screw feeder.

The twin screw conveyor is installed in two rows so that raw materials do not remain at the bottom of the hopper and are completely discharged. Also, when discharging by a narrow screw, only the lower part of the raw materials is discharged and the upper part remains bridging. It should not be generated.

The sewage sludge supplied through the twin screw conveyor is supplied to the hopper of the twin screw feeder of the metering device. In addition, the hopper may have a shape without an inclination angle. This form has the effect of preventing build-up formation of water and sticky sewage sludge is adhered to the wall to prevent quantitative supply.

Specifically, in order to prevent the build-up phenomenon, two twin screw feeders are installed, and the twin screw feeder has a speed adjusting inverter installed so that the supply amount can be adjusted by adjusting the speed.

The hybrid sludge fuel coal production system may further include an energy supply unit as a fuel supply source.

Specifically, the energy supply unit is not particularly limited as long as it is a device capable of supplying heat energy required for drying the drying unit, and in detail, may be a combustor. The combustor may use any one or two or more fuels of solid, liquid and gaseous fuels. Additionally, combustible odor exhaust gas and floating fine powder generated in the drying unit may be additionally used as fuel. The combustible odor exhaust gas may include any one or more of water vapor, aromatic carbon compounds, arsenic acid heavy metals, and volatile organic compounds.

The energy supply unit may be more specifically a natural gas combustor. The hot exhaust gas generated in the natural gas combustor may be directly or indirectly supplied to the drying unit.

The exhaust gas containing the odor discharged from the drying unit may be selectively supplied to the energy supply unit to be reburned and incinerated or discharged to the atmosphere through the exhaust gas treatment unit. The exhaust gas may include unburned carbon powder, ash, etc. generated in the drying unit. The exhaust gas may include a gaseous substance in which exhaust gas containing the malodor emitted from the energy supply unit is combusted. The flue gas may be firstly finely divided through a cyclone. The exhaust gas passing through the cyclone may be condensed and removed from water vapor while passing through the condenser. The exhaust gas passing through the capacitor may be discharged to the atmosphere by an exhaust fan after adsorption and removal of gaseous harmful substances through the adsorption tower. It is apparent that the adsorbent of the adsorption tower may be activated carbon, zeolite, or the like.

In the following, with reference to the embodiment according to the present invention, but for the easier understanding of the present invention, the scope of the present invention is not limited thereto.

<Example 1>

Hybrid sludge fuel coal (HSF-2017-1) made from 70 wt% of sewage sludge and food waste 30wt% under the above conditions and hybrid sludge fuel coal (HSF-2017 made from 70 wt% of sewage sludge, 20 wt% of food waste, and 10 wt% of sawdust) Industrial analysis of -2), sulfur content and low calorific value are shown in Table 1 below.

Hybrid sludge fuel coal (HSF-Hybrid sludge fuel) produced through the above process has high calorific energy (4,300 ~ 4,700 kcal / kg), contains sulfur content less than 1wt%, and removes odor completely through drying process. do. In addition, dust is not generated through the molding process of high compression force. The result is a recycled fuel that is easy to handle and transport.

The HSF fuel can be used as a coal-fired power plant RPS (renewable energy mandatory use for carbon dioxide reduction) fuel can be used for the same purpose as the wood pellet used as the existing RPS fuel can be imported import effect. In addition, it can supply about 30% cheaper than the import price of wood pellets, which can significantly reduce fuel costs.

This system uses organic sewage sludge, which is a malignant waste such as high moisture, odor generation, and leachate generation, to produce fuel coal that can be recycled with high-calorie advanced energy. % By replacing wood pellets imported, it is possible to extend the service life of the landfill site by not only saving foreign currency but also fueling domestic wastes, and also saving much sludge disposal cost burdened by local governments, which will contribute to financial savings of local governments. It becomes possible.

Those skilled in the art to which the present invention pertains will be able to perform various applications and modifications within the scope of the present invention based on the above contents.

10: sewage sludge storage tank
11: Calorie Reinforcement Storage Tank
100: mixing unit
110: first moisture content measuring instrument
120: steam supply device
200: molding unit
300: drying unit
400: cooling unit
420: second moisture content measuring instrument
500: storage unit

Claims (14)

RPS-compatible fuel coal drying production system for power plants using dried sewage sludge,
A mixing unit for generating a mixture by mixing the caloric enhancer with the sewage sludge;
A molding unit for extruding the mixture into cylindrical pellets; And
A drying unit for drying the pellets;
Including;
The mixing unit includes a first moisture content meter for measuring the moisture of the mixture,
A steam supply device is located between the mixing unit and the molding unit,
When the dried sewage sludge is supplied and the moisture content of the mixture measured by the first moisture content meter is lower than the water content range of 15% to 21%, which is suitable for extrusion molding using the molding unit, the mixing unit and the molding Steam is supplied so that the water content of the mixture is between 15% and 21% in the steam feeder located between the units or
If the sewage sludge is supplied in a semi-dry state and a water content of the mixture measured in the first water content meter is higher than 15% to 21%, a drying unit is additionally added to the mixing unit.
The drying unit is a RPS-compatible fuel coal drying production system for a power plant using dried sewage sludge, characterized in that for maintaining a positive pressure of 0.05 atm to 1 atm. delete delete The method of claim 1,
The drying unit, RPS-compatible fuel coal drying production system for a power plant using dried sewage sludge, characterized in that the drying is made by irradiation of microwaves to reduce the water content of the pellet 5% to 15%. The method of claim 4, wherein
The hybrid sludge fuel coal production system,
A cooling unit for cooling the pellets heated in the drying unit;
A second moisture content meter for measuring the moisture content of the cooled pellets; And
A storage unit capable of storing the pellets in a state where moisture is blocked;
RPS-compatible fuel coal drying production system for a power plant using dried sewage sludge, characterized in that it further comprises. delete delete delete RPS compatible fuel coal drying production method for power plant using dried sewage sludge,
(a) mixing sewage sludge and a calorific enhancer;
(b) extruding the mixture mixed in step (a) into cylindrical pellets; And
(c) drying the pellets;
Including;
Step (a) comprises a first moisture content measuring step (a-1) of measuring the water content of the mixed mixture,
Further comprising the step (b-1) of supplying steam before the step (b),
When the dried sewage sludge is supplied and the moisture content of the mixture measured in the first moisture content measurement step is lower than the water content range of 15% to 21% suitable for extrusion molding using the molding unit and the mixing unit and Steam is supplied so that the moisture content of the mixture is 15% to 21% in the steam supply device located between molding units or
If the sewage sludge is supplied in a semi-dry state and a water content of the mixture measured in the first water content measurement step is higher than 15% to 21%, a drying unit is additionally added to the mixing unit.
The drying unit of the drying step RPS corresponding fuel coal drying production method for a power plant using a dry sewage sludge, characterized in that for maintaining a positive pressure of 0.05 atm to 1 atm. delete delete The method of claim 9,
RPS fuel coal drying production method for the power plant using the dried sewage sludge
(d) drying the pellet dried in step (c); And
(e) cooling the heat dried pellets in step (d);
Further includes
Wherein step (e) comprises a second moisture content measuring step (e-1) for measuring the moisture content of the cooled pellets RPS-compatible fuel coal drying production method for a power plant using a dry sewage sludge. The method of claim 9,
Wherein step (c) is irradiated with microwave to reduce the water content of the pellet 5% to 15% RPS-compatible fuel coal drying production method for a power plant using dried sewage sludge. The method of claim 12, wherein the process of steps (c) to (e-1) is repeatedly performed so that the water content range measured in step (e-1) is 10% or less. RPS-compatible fuel coal drying production method for power plant using sewage sludge.

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