KR100908409B1 - Equipment for manufacturing carbides using sludge - Google Patents

Abstract

A carbide manufacturing facility using sludge is provided to improve heat recovery efficiency through feedback of latent heat generated in combustion of the sludge in a carbonization furnace. A carbide manufacturing facility using sludge includes an indirect heating vapor drier(212), a molder(213), a carbonization furnace(214), a re-heating furnace(215), a waste heat boiler(216), a condenser(217), white lead reduction air pre-heater(218), and a cleaning-typed dust collector(220). The indirect heating vapor drier discharges moisture included in the sludge by heating the moisture, and uses the sludge by receiving the latent heat collected from the waste heat boiler as dry calories.

Description

Equipment for manufacturing carbides using sludge

The present invention relates to a carbide manufacturing equipment using sludge, and more particularly, to a carbide manufacturing equipment using sludge with improved heat recovery and improved exhaust gas treatment system.

Conventionally, it has been common to incinerate streams or sewage wastes in general, but there is a problem in that dioxins are generated in the incineration process, and in particular, sludge contains a large amount of water, and thus a large amount of fuel is required for incineration. This causes environmental problems such as energy consumption.

In order to solve this problem, recently, there is a trend to improve the recycling of resources and environmental problems by manufacturing carbide by dry carbonization of sludge.

In general, the carbide manufacturing equipment using sludge is as shown in FIG.

Referring to Figure 1, looks at the carbide manufacturing equipment using a general sludge.

As shown, the conventional sludge carbide production equipment is supplied with a sludge 111, the direct heating air dryer (112) for reducing the amount of water contained in the sludge by heating at a high temperature, the dried sludge powder is constant A molding machine 113 for molding into a pellet or chip form, a carbonization furnace 114 for carbonizing sludge pallet or sludge chips under a high temperature atmosphere, a reburn furnace 115 for burning gas generated in the carbonization furnace 114, and In addition, the supply gas for resupplying the combustion gas generated in the reburn furnace 115 as a hot gas to the direct heating air dryer 112, and the high pressure gas generated in the reburn furnace 115 is cooled to the white smoke reduction air preheater 118. Outgoing gas cooling tower 116 and combustion air preheater 117, white smoke reduction air preheater 118, filtration precipitator 119 and cleaning precipitator to reduce and dust-collect the gas delivered from the combustion air preheater 117 ( 120) It achieved by also.

However, in the conventional carbide manufacturing equipment using sludge, problems of energy recovery efficiency and exhaust gas treatment in the reburn furnace 115 occur.

Carbide manufacturing equipment using conventional sludge uses a large amount of exhaust gas because it uses the sensible heat of the exhaust gas, and there is a problem in that a large amount of fuel is consumed to burn at 850 ° C. in the reburn furnace as it is because the amount of exhaust gas is large.

In the case of a conventional sludge carbide production equipment, the gas cooling tower 116, the combustion air preheater 117, the low smoke air preheater 118, the filtration precipitator 119, and the cleaning precipitator 120 at the rear stage. It is difficult to remove when dust is accumulated due to a complicated treatment process, and there is a problem that a large amount of exhaust gas is generated.

An object of the present invention for solving the above-mentioned problems is to burn a gas generated in conjunction with carbonization of sludge in a carbonization furnace, and feed back to a dryer by using latent heat generated during combustion to increase heat recovery efficiency. An object of the present invention is to provide a carbide manufacturing apparatus capable of increasing the exhaust gas treatment efficiency.

Carbide manufacturing equipment using the sludge according to the present invention for solving the above problems, by heating the sludge by hot steam to remove the water contained in the sludge, the dry sludge from the water is removed through a conveyor into a carbonization furnace An indirect heating steam dryer for supplying; A carbonization furnace for carbonizing the dry sludge under a high temperature atmosphere; A reburn furnace for burning the gas generated in the carbonization furnace; A waste heat boiler for supplying the heat generated from the reburn furnace to the indirect heated steam dryer as high temperature steam; And a condenser for cooling the steam discharged from the indirect heating steam dryer to condense the vaporized vapor and supply it to the reburn furnace.

Here, the treatment of the exhaust gas generated in the carbide production equipment using the sludge is characterized in that it consists of three processes: a white smoke reduction air preheater, a filter dust collector and a cleaning dust collector.

According to the configuration of the present invention described above, by burning the gas generated in conjunction with the carbonization of the sludge in the carbonization furnace, feed back to the dryer by using the latent heat generated during combustion to increase the heat recovery efficiency and increase the exhaust gas treatment efficiency It is possible to provide a carbide manufacturing facility which can be used.

Hereinafter, a carbide manufacturing apparatus using sludge according to the present invention will be described with reference to the accompanying drawings.

Figure 2 shows a block diagram of the carbide production equipment using the sludge of the present invention.

As shown, the carbide manufacturing equipment using the sludge of the present invention is indirect heating steam dryer 212, molding machine 213, carbonization furnace 214, reburn furnace 215, waste heat boiler 216, condenser 217 , A white smoke reduction air preheater 218, a filter dust collector 219, and a cleaning dust collector 220.

The indirect heating steam dryer 212 receives the sludge 211 and discharges it by reducing the amount of moisture contained in the sludge 211 at a high temperature, and drying the sludge 211 by feeding back the latent heat recovered from the waste heat boiler 216. Use in calories to make.

The molding machine 213 forms a powder of sludge dried from the indirect heating steam dryer 212 into a pellet or chip of a predetermined shape and supplies it to the carbonization furnace 214.

The carbonization furnace 214 carbonizes the sludge pallet or sludge chips supplied from the molding machine 213 under a high temperature atmosphere. The structure of the carbonization furnace 214 includes a direct heating rotary type, an indirect heating rotary type, and an indirect heating screw type.

The reburn furnace 215 combusts the gas generated in the carbonization furnace 214, and sends heat generated at this time to the waste heat boiler 216.

The waste heat boiler 216 heats the heat generated from the reburn furnace 215 to high temperature steam and feeds it back to the indirect heating steam dryer 212 so that the indirect heating steam dryer 212 serves as a heat source for drying the sludge 211. Do it.

The condenser 217 cools the steam discharged from the indirect heating steam dryer 212 and condenses the vaporized vapor to be supplied to the reburn furnace 215.

Most of the steam generated from the waste heat boiler 216 is supplied to the indirect heating steam dryer 212 for drying the sludge 211, and the remaining part is sent to the low smoke air preheater 218 to remove the attached dust and washed. It is included in the exhaust gas through the dust collector 220 and is discharged to the atmosphere.

In addition, the exhaust gas generated from the waste heat boiler 216 is discharged to the atmosphere through the filter dust collector 219 and the cleaning dust collector 220.

The carbonization furnace of this structure has better energy recovery than conventional carbide production facilities, simplifies the process of treating exhaust gases, and emits small amounts of exhaust gases, thereby providing energy and environment-friendly facilities. More specifically, the energy recovery rate and the exhaust gas emissions will be described below in comparison with the conventional one.

The following shows the process balance of direct heating air drying (conventional) and indirect heating steam drying (invention) for 100 tons of sewage sludge per day, and the heat dissipation rate, leakage and air volume of the device for basic comparison. The rate of pyrolysis of carbonization is to be the same as possible.

[Comparison of Heat Sources Used for Sludge Drying]

First, the sludge shown in FIGS. 1 and 2 is dried, and the processes up to the molding machines 113 and 213 and the carbonization furnaces 114 and 214 are the same, and the heat from the heat or carbonization furnaces 114 and 214 required for sludge drying is exhausted. The amount of exhaust gas is also the same.

That is, 3,056 Kg / h (water evaporating) x 600 kcal / kg (latent heat of evaporation) = 1,833,333 kcal / h is required calorie in order to evaporate the water contained in the sludge.

In the case of the direct heating wind drying (conventional), since the sensible heat of the exhaust gas is used, a large amount of the exhaust gas is required, whereas in the case of the indirect heating steam drying (the present invention), it is heated by the latent heat of the steam. Can be.

In general, latent heat is a quantity of heat accompanied by a change of state, for example, when moisture changes from liquid water to water vapor, its temperature does not change but only a change in heat of about 600 kcal / kg. In contrast, since sensible heat is accompanied by a change in temperature, there is only a change in calories for a specific heat (kcal / Nm3 ° C.) × change in temperature (° C.) due to a change in heat without a change in state.

Sensible heat is distinguished by these words because latent heat does not know the change in temperature, and of course, latent heat is known by the change of state (liquid → gas, gas → liquid) even if the temperature does not change. Can be.

In the case of direct heating wind drying (conventional), the amount of exhaust gas required = calories required for evaporation ÷ exhaust gas average specific heat ÷ (exhaust gas inlet temperature-exhaust gas outlet temperature).

Since the specific heat of exhaust gas is about 0.35kcal / Nm ³ ℃ entrance temperature difference is about 500 ℃, simply calculate 1,833,333 ÷ 0.35 ÷ 500 = 10,500 Nm ³ / h exhaust gas and consider cooling by leak air. This would require 12,346 Nm ³ / h of more exhaust gas.

In the case of indirect heating steam drying (the present invention), since steam uses indirect heat to dry the sludge and steam is a drain, it can be dried with a small amount of steam. That is, the amount of steam required = latent heat of calories ÷ steam necessary for evaporation.

When condensing 9 kgf / cm ² steam and recovering from 2 kgf / cm ² hot water, 662 (enthalpy at 9 kgf / cm ² ) -133 (enthalpy at ² kgf / cm ² ) = 529 kcal / kg steam From a simple calculation, the required steam volume is 1,833,333 ÷ 529 = 3,465 kg steam / h, and 3,972 kg / h steam volume is required for condensing 8 kgf / cm ² steam and recovering it from 2 kgf / cm ² hot water. Done.

[Exhaust amount in the dryer]

In the case of direct heating wind drying (conventional), the exhaust gas from the dryer 112 becomes 18,148 Nm ³ / h as the evaporative water of the inlet exhaust gas + sludge to directly contact the sludge to evaporate the moisture, and the indirect heating steam. In the case of drying (the present invention), since the heat-exchanged steam is recovered as a drain, the exhaust gas of the dryer 212 becomes only 5,802 Nm ³ / h as the amount of evaporated water + leak air from the sludge.

[Exhaust gas coming into the reburn furnace]

In the case of direct heating wind drying (conventional), since the amount of exhaust gas (14,838 Nm ³ / h, 624 ° C.) is large, since a large amount of fuel is required to burn the combustion furnace 115 at 850 ° C., the reburn furnace 115 It is necessary to reduce the fuel consumption by raising the exhaust gas temperature by exchanging a part of the outlet exhaust gas with the combustion air preheater 117.

On the other hand, in the case of indirect heating steam drying (invention), the amount of exhaust gas (2,275 Nm ³ / h, 50 ° C.) delivered to the reburn furnace 215 by condensing the vapor evaporated by cooling the exhaust gas in the condenser 217. Can be reduced to an extreme.

In other words, since the amount of exhaust gas is small, it is not necessary to heat exchange with the combustion air preheater, and thus an installation without the combustion air preheater is possible.

[Fuel consumption to reburn]

In the case of direct heating wind drying (conventional), the amount of exhaust gas in the reburn furnace 115 (14,838 Nm ³ / h, 624 ° C.) is very large, and in the case of indirect heating steam drying (invention), the amount of exhaust gas (2,275 Nm ³ / h, 50 ° C) is small in spite of the low temperature, so the required fuel consumption in the reburn furnace is very different.

That is, in the case of direct heating wind drying (conventional), the reburn furnace 115 consumes 159 kg / h (heavy oil), and indirect heating steam drying (invention) reburn furnace 215, consumes 40 kg / h (heavy oil). ), Only about 4 times less energy can be saved in terms of fuel consumption.

[Exhaust Gas Exhaust by Reburning]

In the case of direct heating wind drying (conventional), the amount of exhaust gas exhausted from the reburn furnace 115 (23,641 Nm3 / h 850 ° C.) is large, and in the case of indirect heating steam drying (invention), the amount of exhaust gas exhausted from the reburn furnace 215. (9,446 Nm 3 / h 850 ° C.) is very low.

[Required relationship of exhaust gas distribution]

In the case of direct heating wind drying (conventional), some of the reburn furnace 115 exhaust gas is sent to the combustion air preheater 117 by dropping the temperature in the gas cooling tower 116 for sludge drying at 850 ℃. This is because the inlet gas temperature of the filter dust collector 119 needs to be reduced to 170 to 180 ° C, but water spraying in the gas cooling tower 116 for controlling the process temperature further increases the amount of exhaust gas in case of exhaust gas drying. do. On the other hand, indirect heating steam drying (the present invention) can reduce the amount of exhaust gas due to the installation structure does not require a gas cooling tower.

Gas cooling tower spray water (direct heating hot air drying) is 851 kg / h, gas cooling tower spray water quantity (indirect heating steam drying) does not require gas cooling tower, and 15,749 Nm for filter dust collector inlet exhaust gas (direct heating hot air drying) ³ / h 180 ℃ is discharged, 9,446 Nm ³ / h 175 ℃ is emitted in the case of the bag filter inlet exhaust gas (indirect heating steam drying).

[Final exhaust gas including smoke reduction]

In the case of direct heating wind drying (conventional), the chimney exhaust exhaust gas is discharged at 23,118 Nm ³ / h 198 ° C. In the case of indirect heating steam drying (invention), the chimney exhaust exhaust gas is 10,093Nm ³ / h 167 ° C. Discharged.

[Exhaust gas composition and white smoke prevention range]

According to [Table 1], in case of direct heating air drying, the exhaust gas has a large amount of exhaust gas and a high moisture content, and indirect heating steam drying becomes exhaust gas having a low moisture ratio when cooling the exhaust gas in a boiler. Therefore, as shown on the next page, the exhaust gas of indirect heating steam drying significantly extends the application range of the smoke prevention.

Although the preferred embodiments of the present invention have been described above with reference to the accompanying drawings, the above-described technical configuration of the present invention may be embodied by those skilled in the art to which the present invention pertains without changing its technical spirit or essential features of the present invention. It will be appreciated that the present invention may be practiced as. Therefore, the above-described embodiments are to be understood as illustrative and not restrictive in all respects, and the scope of the present invention is indicated by the appended claims rather than the detailed description, and the meaning and scope of the claims and All changes or modifications derived from the equivalent concept should be interpreted as being included in the scope of the present invention.

1 is a block diagram of a carbide manufacturing facility using a conventional sludge.

Figure 2 shows a block diagram of the carbide production equipment using the sludge of the present invention.

Claims (2)

An indirect heating steam dryer for heating the sludge by hot steam fed back from the waste heat boiler to remove water contained in the sludge, and supplying the dried sludge to the carbonization furnace through the conveyor; A carbonization furnace for carbonizing the dry sludge under a high temperature atmosphere; A reburn furnace for burning the gas generated in the carbonization furnace; A waste heat boiler for supplying heat generated from the reburn furnace to the indirect heating steam dryer as high temperature steam and discharging the exhaust gas; And a condenser for condensing the steam discharged from the indirect heated steam dryer and discharging condensed water and supplying the steam to the reburn furnace. The method of claim 1, The treatment of the exhaust gas generated from the carbide production equipment using the sludge is a sludge carbide production equipment consisting of three processes: a low smoke air preheater, a filter dust collector and a cleaning dust collector.

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