JP2013133269A - Method for controlling operation of cement production facility - Google Patents

Abstract

PROBLEM TO BE SOLVED: To enable accurate management by an odor index, by measuring continuously each odor of various exhaust gases from a cement production facility.SOLUTION: In this method for controlling operation of the cement production facility for producing cement, while treating waste, in the cement production facility, waste before charging into the cement production facility is sampled and heated to 550°C at the maximum, and the total hydrocarbon amount in volatile gas generated by the heating is measured, and the amount of increase of the total hydrocarbon amount in the exhaust gas discharged from the cement production facility is predicted based on the measurement result, and the input amount of waste into the cement production facility is controlled based on the prediction result.

Description

  The present invention relates to an operation control method when processing waste in a cement manufacturing facility, and more particularly to an operation control method for controlling the amount of waste input while predicting the odor of exhaust gas.

  In recent years, various industrial wastes have been used as a part of cement raw materials and cement burning fuels for disposal. This industrial waste contains waste plastics, soil containing oil and cleaning agents, and various sludges. As a result, carbon and organic components that do not originate from coal are generated. It was. Since the exhaust gas generated by volatilization from these industrial wastes or their combustion contains odorous substances, it must be managed.

  According to Patent Documents 1 to 3, the present applicant previously measured the total amount of hydrocarbons in the exhaust gas generated from the cement production facility (Total HydroCarbon: abbreviated as THC for short), and the total hydrocarbons. A technique to estimate the odor index of exhaust gas from the quantity was proposed.

JP 2009-192482 A JP 2010-151649 A JP 2010-151650 A

  The technologies proposed in Patent Documents 1 to 3 enable continuous grasp of the odor in the exhaust gas from the cement production facility. However, simply by developing such a measurement technique, It was not possible to improve the efficiency of the product itself, and it was feared that the odor index of the exhaust gas would rise, and only a small amount of waste could be treated.

  The present invention has been made in view of such circumstances, and an object of the present invention is to provide a method for controlling the operation of a cement production facility capable of treating waste efficiently with maximum efficiency while suppressing odor in exhaust gas. To do.

When waste is input to cement production facilities, it is possible to know in advance how much the odor component will increase due to the waste.By controlling the input amount, the odor component in the exhaust gas is reduced to a predetermined amount or less. Can be managed. In this case, it is only necessary to be able to grasp the burnt odor as an odor component derived from organic matter, and if the total hydrocarbon amount is measured from the volatile gas generated by heating the waste, the total hydrocarbon amount when it is input to the cement production facility The increase can be grasped.
In this case, as a result of earnest research, the present inventor has mixed various organic substances in the waste. When heated, most of the organic substances evaporate at around 350 ° C., and the remaining organic substances are also removed. It was found that most of the organic substances volatilized at around 450 ° C. and most of the organic substances volatilized up to 550 ° C. Then, even if it heats to 600 degreeC, for example, the volatile component hardly contains the odor component which causes a burning odor, and decomposition | disassembly will generate | occur | produce above 600 degreeC. For this reason, the knowledge that heating waste to a maximum of 550 ° C. is sufficient for grasping the burnt odor was obtained.

That is, the present invention is an operation control method of a cement production facility for producing cement while processing the waste in the cement production facility, heating a sample collected from the waste before being put into the cement production facility, Measure the total hydrocarbon amount in the volatile gas generated by the heating, predict the increase in the total hydrocarbon amount in the exhaust gas released from the cement production facility based on the measurement result, and manufacture the cement based on the prediction result It is characterized by controlling the amount of waste input to the facility.
In that case, the heating temperature of the sample may be set to a maximum of 550 ° C.

  Of the organic matter in the waste, the total amount of hydrocarbons due to the organic matter that causes the burning odor is measured in advance, so the impact on the odor component due to the input of waste, in other words, the total carbonization due to the input of waste The amount of increase in hydrogen can be grasped in advance. Therefore, if the operation of the cement production facility is controlled by this method, it is possible to treat waste as much as possible without adversely affecting the environment.

  According to the operation control method for a cement production facility according to the present invention, it is possible to grasp the increase in the total hydrocarbon amount due to the input before introducing the waste into the cement production facility, so that there is no adverse effect on the environment. Waste can be treated to the maximum extent, and its processing efficiency is good.

It is a block diagram which shows the example of the total hydrocarbon amount measuring apparatus used for implementation of the operation control method of this invention. It is a whole system lineblock diagram showing cement manufacturing equipment. It is a graph which shows the relationship with the heating temperature of the amount of THC in the volatile gas which generate | occur | produces by heating a waste material. It is a graph which shows the ratio of the THC amount by heating temperature for every raw material when the THC amount in the volatile gas generated by heating waste (raw material) to 550 degreeC is set to 100. It is a graph which shows the correlation with the amount of THC in the exhaust gas estimated by the method of this invention, and the amount of THC in the exhaust gas actually measured. It is a graph which shows the relationship between the odor index estimated by the method of this invention, and the time fluctuation | variation of the odor index at the time of throwing a waste into a cement manufacturing equipment. It is a graph which shows the correlation with the amount of THC in the waste gas estimated by heating waste to about 650 degreeC, and the amount of THC in the waste gas actually measured.

Hereinafter, an embodiment of an operation control method for a cement production facility according to the present invention will be described with reference to the drawings.
FIG. 1 shows a total hydrocarbon amount measuring device 21 used for predicting odor components in exhaust gas from a cement production facility when carrying out the operation control method of the present invention.
This total hydrocarbon amount measuring device 21 includes a heating furnace 22 made of, for example, an electric furnace, and a carrier gas supply system that supplies a carrier gas such as nitrogen gas for transporting a volatile gas of a sample heated in the heating furnace 22. 23, a THC measuring device 24 for measuring the total amount of hydrocarbons in the volatile gas transported with the carrier gas, and an increase in the odor index when treated in a cement production facility is predicted from the measurement result of the THC measuring device 24 The odor index predicting means 25 is provided.

The carrier gas supply system 23 includes a gas container 26 that stores the carrier gas, and a flow meter 27 that measures the flow rate from the gas container 26, and the carrier gas is supplied from the gas container 26 into the heating furnace 22. It is supplied at a predetermined flow rate.
The heating furnace 22 is provided with a furnace core tube 29 that accommodates the sample 28, and a carrier gas is circulated in the furnace core tube 29 to send volatile gas to the THC measuring device 24.

The THC measuring device 24 is a measuring device based on, for example, a hydrogen ionization detector (FID). By sending and igniting exhaust gas and hydrogen of fuel from a nozzle, organic substances in the exhaust gas are combusted in a hydrogen flame. The ion current due to carbon ions generated between the collector electrodes sandwiching the flame is measured.
The odor index predicting means 25 preliminarily formulates a correlation between the total hydrocarbon amount and the odor index and stores it in a computer, and the odor index according to the formula from the measured value of the total hydrocarbon amount obtained from the THC measuring device 24. The amount of increase is predicted.

  This odor index was measured by olfactory measurement method (method of calculating odor index and odor emission intensity), and the sample was diluted with odorless air until the subject who passed the test of normal olfaction no longer felt odor. It is a numerical value obtained by multiplying the common logarithm value by 10 and calculating the dilution ratio (odor concentration). The calculation formula is expressed as odor index = 10 × Log (odor concentration). As a specific method of measurement, the “three-point comparison odor bag method” is adopted. In this three-point comparison odor bag method, two of the three bags are filled with odorless air, and the remaining one bag is filled with a sample diluted to a predetermined dilution factor. Is a method in which six or more subjects repeat the process of determining the presence or absence of odor in each bag while changing the dilution factor, and obtain the dilution factor at which no odor is felt.

  Further, the odor index and the total hydrocarbon amount have a relationship of odor index = a × log (total hydrocarbon amount) + b, and the constants a and b vary depending on the type of waste, etc. Obtaining in advance by pilot operation or the like is performed.

  On the other hand, FIG. 2 shows a cement production facility to which the operation control method of the present invention is applied. This cement production facility 1 bakes a raw material mill and dryer 2 for pulverizing and drying cement raw material, a preheater 3 for preheating the powder raw material obtained by this raw material mill, and a powder raw material preheated by the preheater 3. A kiln 4 and a cooling machine (not shown) for cooling the cement clinker after firing in the kiln 4 are provided.

  The kiln 4 heats and sinters the cement raw material supplied from the preheater 3 to 1450 ° C. or higher with a burner while rotating a horizontal cylindrical shell to generate a cement clinker. In this case, the exhaust gas from the kiln 4 is introduced into the raw material mill and the dryer 2 via the preheater 3, and the raw material mill and the dryer 2 are introduced by introducing the exhaust gas from the kiln 4, Cement raw materials are pulverized and dried simultaneously. The preheater 3 is of a multistage cyclone type in which a plurality of cyclones are connected in multiple stages from the bottom to the top, and the cement raw material crushed by the raw material mill is preheated to a predetermined temperature using the exhaust gas from the kiln 4. To do.

In this cement manufacturing facility 1, the double solid line arrows in FIG. 2 indicate the flow of obtaining cement clinker from the cement raw material.
On the other hand, the flow of exhaust gas generated by combustion in the kiln 4 is indicated by broken lines. This exhaust gas passes through the preheater 3, the raw material mill and the dryer 2, and the heat source and raw material for preheating the powder raw material in the preheater 3 After being used as a heat source for drying in the mill and dryer 2, it is sent to the dust collector 5, and after dust is removed by the dust collector 5, it is discharged from the chimney 6 to the atmosphere.

  The dust collector 5 is an electric dust collector that collects dust in exhaust gas by using static electricity generated by high voltage discharge, for example, and dust such as ash mixed as solids in the exhaust gas is collected at the electrode. Is done. In addition to the electric dust collector, a known dust collector such as a bag filter or a cyclone can be used as long as it can collect a solid content in the exhaust gas. The collected dust is input to the raw material mill through the dust delivery pipe 7.

  An exhaust gas odor measuring device 11 is provided between the dust collector 5 and the chimney 6. This exhaust gas odor measuring device 11 is provided with a sampling unit 13 for extracting a part of exhaust gas in a pipe 12 between the dust collector 5 and the chimney 6, and the sampling unit 13 includes a THC measuring instrument 14 and a specific gas. A carbon monoxide amount measuring device 15 for measuring the amount of carbon monoxide is connected in parallel, and the THC measuring device 14 corrects the measured value of the total hydrocarbon amount by the measured value of the carbon monoxide amount. And the odor index estimation means 17 for estimating the odor index of the exhaust gas from the corrected total hydrocarbon amount is provided.

  The THC measuring instrument 14 is a measuring instrument based on, for example, a hydrogen ionization detector (FID), similar to that used in the total hydrocarbon content measuring apparatus 21 described above.

  The carbon monoxide amount measuring device 15 is a measuring device based on, for example, a non-dispersive infrared analysis method, and utilizes the property that carbon monoxide selectively absorbs infrared light having a specific wavelength. The component concentration is measured from the amount of infrared absorption.

  These THC measuring device 14 and carbon monoxide amount measuring device 15 continuously measure the total hydrocarbon amount and carbon monoxide amount of the exhaust gas at the same timing. Then, the correction means 16 corrects the total hydrocarbon amount continuously measured by the THC measuring instrument 14 by the carbon monoxide amount measured at the same timing as this, and the peak value appears in the measured value of the carbon monoxide amount. When a peak is generated, it is determined whether or not a peak portion is generated in the measured value of the total hydrocarbon amount at the timing when the peak portion is generated. Is generated, the measured value is transferred to the next odor index estimating means 17 with the peak portion of the total hydrocarbon amount being excluded, assuming that the peak portion is due to the effect of incomplete combustion.

  The odor index estimating means 17 formulates the correlation between the total hydrocarbon amount and the odor index in advance in the same manner as the odor index predicting means 25 described above and stores it in a computer, and the corrected odor obtained from the correcting means 16 is stored. The odor index is estimated from the measured value of the total hydrocarbon amount according to the mathematical formula.

Next, an operation control method for manufacturing cement while processing waste in the cement manufacturing facility 1 will be described.
First, a part of the introduced waste is sampled and the total hydrocarbon amount is measured by the total hydrocarbon amount measuring device 21. In this case, the sample 28 collected from the waste is placed in the furnace core tube 29 of the heating furnace 22, the carrier gas is flowed, and the volatile gas is transported to the THC measuring device 24 for measurement. The waste is heated up to 550 ° C., and the total hydrocarbon amount of the gas volatilized until reaching 550 ° C. is continuously measured, and the accumulated amount is defined as the total hydrocarbon amount of the waste.

  FIG. 3 shows a relationship with the temperature of the total hydrocarbon amount (THC amount) in the volatile gas generated when the waste is heated. The reason for the multiple data is that it is shown for each waste collected at different times and places. As is apparent from FIG. 3, the THC content of all the wastes is remarkably increased at around 350 ° C. Some increase slightly around 450 ° C., decrease around 550 ° C., and increase again around 600 ° C.

  In order to suppress the odor component at the time of processing with the cement manufacturing facility 1 among the total hydrocarbon amount, it is only necessary to be able to grasp the burnt odor as the odor component derived from the waste. In the total amount of hydrocarbons in FIG. 3, most of the odor components that cause burnt odors are volatilized around 350 ° C. and almost volatilized around 450 ° C. The volatile components around 600 ° C. Contains almost no odor components. In addition, decomposition occurs at 600 ° C. or higher. For this reason, the burnt odor in the volatile gas from a waste can be grasped | ascertained by heating waste to 550 degreeC in which generation | occurrence | production of THC decreases and measuring the total amount of hydrocarbons.

FIG. 4 shows the THC amount in the volatile gas of the raw material (waste) at each heating temperature of 500 ° C. or lower and 550 ° C. or less, and the ratio when the THC amount at 550 ° C. is 100 for each raw material. It is shown. As shown in FIG. 4, the amount of THC depending on the heating temperature varies depending on the type of the raw material. For example, the raw material H and the raw material I do not heat to 550 ° C., but the THC amount at about 500 ° C. and 550 ° C. The amount of THC is almost equal to. Conversely, the raw material F has a large change in the THC amount due to the heating temperature, and it is necessary to measure the THC amount by heating to 550 ° C.
Thus, when measuring the THC amount of waste, the waste may be heated to a specific temperature determined by the raw material within a range of 550 ° C. at the maximum.

  FIG. 5 shows the THC amount of exhaust gas at a cement production facility predicted based on the THC amount of raw material (waste) measured by heating to 550 ° C. with the total hydrocarbon amount measuring device 21 and the actual raw material. It is a graph which shows the correlation with the amount of THC in the waste gas which arises when thrown into a cement manufacturing facility. As is apparent from this graph, the correlation between the two is high, and the amount of THC when charged into the cement production facility 1 can be accurately grasped from the amount of THC measured by heating to 550 ° C.

  FIG. 7 shows the correlation between the amount of THC measured by heating waste to over 650 ° C. to about 650 ° C., and the amount of THC in the exhaust gas generated when the waste is put into a cement manufacturing facility. However, the correlation between the two is low. Therefore, in order to predict the THC amount in the exhaust gas from the cement manufacturing facility 1, the waste may be heated to a maximum of 550 ° C. and the THC amount measured.

In this way, the THC amount of the waste is measured, and the odor index predicting means 25 predicts the increase amount of the odor index when the waste is input to the cement manufacturing facility 1 from the measured value.
And based on this prior prediction result, a cement is manufactured, processing an appropriate amount of wastes by the cement manufacturing equipment 1.
Exhaust gas from the cement manufacturing facility 1 is discharged into the atmosphere from the chimney 6 after dust is removed by the dust collector 5, but a part of the exhaust gas is sampled by the sampling unit 13 between the dust collector 5 and the chimney 6, The total hydrocarbon amount and the carbon monoxide amount are continuously measured by the THC measuring device 14 and the carbon monoxide amount measuring device 15, and the odor index in the exhaust gas is estimated by the correcting means 16 and the odor index estimating means 17.

FIG. 6 shows the temporal variation of the odor index when the waste is put into the cement manufacturing facility, and the odor index predicted by the method of the present invention is almost the predicted value as indicated by the alternate long and short dash line (a). It can be seen that it fluctuates within the range.
Therefore, if this operation control method is used, it is possible to make a waste input plan that predicts the effect on the odor index in the exhaust gas, and it is possible to avoid an increase in odor that will adversely affect the surrounding residents. Equipment operation can be stabilized.

In addition, this invention is not limited to the said embodiment, A various change can be added in the range which does not deviate from the meaning of this invention.
For example, the odor index was predicted by measuring the total amount of hydrocarbons in the waste, but there is a certain correlation between the total hydrocarbon amount and the odor index, so the total hydrocarbon amount can be measured without calculating the odor index. The amount of waste input may be controlled based on the value.
Further, in the above embodiment, the amount of THC was measured by heating the waste to 550 ° C., but depending on the type of waste, for example, THC that affects the odor component at about 450 ° C. or 500 ° C. may be almost volatilized. There are cases where it is possible. In such a case, it is not necessary to heat up to 550 ° C., and in such a case, it may be heated in a range up to 550 ° C.

DESCRIPTION OF SYMBOLS 1 Cement manufacturing equipment 2 Raw material mill and dryer 3 Preheater 4 Kiln 5 Dust collector 6 Chimney 11 Exhaust gas odor measuring device 13 Sampling part 14 THC measuring device 15 Carbon monoxide amount measuring device 16 Correction means 17 Odor index estimating means 21 Total hydrocarbon measuring device 22 Heating furnace 23 Carrier gas supply system 24 THC measuring instrument 25 Odor index predicting means 26 Gas container 27 Flow meter 28 Sample 29 Furnace core tube

Claims (2)

  A method for controlling the operation of a cement manufacturing facility that manufactures cement while processing the waste at the cement manufacturing facility, wherein the sample collected from the waste before being put into the cement manufacturing facility is heated, and the volatilization generated by the heating Measure the total amount of hydrocarbons in the gas, predict the increase in the total amount of hydrocarbons in the exhaust gas released from the cement production facility based on the measurement results, and based on the prediction results, An operation control method for a cement manufacturing facility, characterized by controlling an input amount.   The method for controlling operation of a cement production facility according to claim 1, wherein the heating temperature of the sample is set to a maximum of 550 ° C.

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