JP2007014875A - Method for deodorizing polymerization furnace - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a method for deodorizing a polymerization furnace capable of performing energy-saving operation by virtue of a prediction control of the flow rate of an exhaust necessary for removing an odor according to a predicted pattern of the odor concentration calculated from a pre-measured generation pattern of the odor concentration generated upon thermally polymerizing a raw material composition. <P>SOLUTION: The polymerization furnace 1 is equipped with an exhaust fan 42 that discharges an atmospheric gas of a furnace chamber 22, an exhaust path 41, an exhaust damper 43 that controls the amount of the atmospheric gas being discharged and flowing through the exhaust path 41, an odor-measuring device 44, a deodorizing device 45, and an odor control section 46 that controls the flow rate of the exhaust by virtue of the exhaust fan 42 and exhaust damper 43 based on the odor concentration detected by the odor-measuring device 45. The odor control section 46 calculates a predicted pattern of the odor concentration based on the pre-measured pattern of the odor concentration generated upon thermally polymerizing a raw material composition, controls the flow rate of the exhaust according to the calculated prediction pattern of the odor concentration, and controls and corrects the flow rate of the exhaust in case the odor concentration detected by the odor measuring device 44 has exceeded a predetermined range. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a deodorizing method for a polymerization furnace in which a raw material composition is thermally polymerized.

  In manufacturing a plastic lens such as an eyeglass lens, a shape having a desired optical performance is formed by a cast molding method, an injection molding method, a cutting polishing method, or the like. Of these, the casting method is widely used for the production of high-performance plastic lenses. The casting molding method is a method in which two glass molds having a desired molding surface are arranged opposite to each other at a predetermined interval, and a raw material composition is injected into a mold die whose peripheral surface is sealed with an adhesive tape or the like. The raw material composition can be heated and cured (thermal polymerization) to obtain a plastic lens.

  For the thermal polymerization of such raw material compositions, a polymerization furnace is generally used as a temperature control device. In the thermal polymerization, the mold die into which the raw material composition is injected is placed in a polymerization furnace, the temperature of the polymerization furnace is controlled to a predetermined temperature pattern (see FIG. 1 described later), and the raw material composition is cured. . During this thermal polymerization, the mold (raw material composition) is temperature-controlled (heated) to about 30 to 120 ° C. within an elapsed time of about 20 hours, and odors such as hydrocarbon compounds are produced from the raw material composition to be polymerized. appear. It is required to efficiently exhaust and deodorize the generated odor from the inside of the polymerization furnace.

  Although different from the polymerization furnace, the operation pattern of dust generated from the factory is automatically selected based on conditions such as gas temperature and dust concentration, and the rotation speed of the suction fan is controlled by a rotation speed controller such as an inverter to save energy. A management system for a dust collector that operates is proposed (see, for example, Patent Document 1).

Japanese Patent No. 2777770

However, since the above dust collector selects an operation pattern according to the measured values of gas temperature and dust concentration and controls the rotation speed of the suction fan, a time lag occurs and dust in the environment (factory) is generated. When the concentration is not uniform, it is assumed that an intake operation more than necessary is performed in order to perform reliable intake.
Therefore, the present invention predicts and controls the exhaust intensity for deodorizing the odor from the predicted pattern based on the generation pattern of the odor concentration of the odor generated during the thermal polymerization of the raw material composition measured in advance, thereby enabling energy saving operation. A method for deodorizing a polymerization furnace is provided.

  In order to solve the above problems, a deodorizing method for a polymerization furnace according to the present invention is a deodorizing method for a polymerization furnace in which a raw material composition is thermally polymerized, and the polymerization furnace includes an exhaust fan for exhausting an atmosphere in the polymerization furnace, and An exhaust passage for guiding the atmosphere in the polymerization furnace to the exhaust fan, an exhaust damper for controlling an exhaust amount of the atmosphere flowing through the exhaust passage on the exhaust passage with an opening degree, and an exhaust damper An odor measuring device for detecting an odor concentration in the polymerization furnace on the upstream exhaust passage, a deodorizing device for removing odor contained in the atmosphere on the exhaust passage downstream of the exhaust damper, and An odor control unit that controls exhaust intensity of the exhaust fan and the exhaust damper based on an odor concentration detected by an odor measuring device, and the odor control unit is configured to measure the raw material composition measured in advance during thermal polymerization. Odor concentration generated An odor concentration prediction pattern is calculated based on the occurrence pattern, the exhaust intensity is controlled according to the calculated odor concentration prediction pattern, and the odor concentration detected by the odor measuring device is a predetermined value of the prediction pattern. When the above range is exceeded, control for correcting the exhaust intensity is performed.

  According to this, the odor control unit constituting the polymerization furnace calculates the predicted pattern of the odor concentration based on the generation pattern of the odor concentration generated during the thermal polymerization of the raw material composition measured in advance, and the calculated odor concentration In accordance with the predicted pattern, the exhaust fan exhausting the atmosphere in the polymerization furnace and the exhaust damper exhaust intensity are controlled, and when the odor concentration detected by the odor measuring device exceeds a predetermined range of the predicted pattern, Deodorization method for a polymerization furnace capable of removing odor generated during thermal polymerization of a raw material composition by performing energy-saving operation without consuming wasteful power by performing control to correct the exhaust strength of an exhaust fan and an exhaust damper Is obtained.

In the deodorization method for a polymerization furnace according to the present invention, the exhaust intensity is controlled by controlling the frequency of the operation of the exhaust fan and controlling the opening degree of the exhaust damper.
According to this, the predicted pattern of the odor concentration is calculated based on the generation pattern of the odor concentration generated during the thermal polymerization of the raw material composition measured in advance, and according to the calculated predicted pattern of the odor concentration, the exhaust fan The frequency of the operation is controlled and the opening degree of the exhaust damper is controlled so that the odor generated during the thermal polymerization of the raw material composition can be removed by energy saving operation without consuming unnecessary power. The deodorizing method is obtained.

  Further, in the method for deodorizing a polymerization furnace according to the present invention, the prediction pattern is a pattern corresponding to a volume value of the raw material composition charged into the polymerization furnace based on the generation pattern of the odor concentration measured in advance. It is characterized in that it is calculated as follows.

  According to this, the odor concentration of the odor generated from the raw material composition to be polymerized shows a value substantially proportional to the volume of the raw material composition. Therefore, it is possible to predict the odor concentration of various volumes to be polymerized based on the odor concentration generation pattern measured in advance. It is desirable that the generation pattern of the odor concentration to be measured in advance is measured for at least two types of odor concentration generation patterns of different volumes for each type of raw material composition. Thereby, an odor density | concentration can be estimated by calculating proportionally between two calibration curves corresponding to the volume of the raw material composition to superpose | polymerize.

Moreover, the deodorizing method for a polymerization furnace according to the present invention is characterized in that the raw material composition is a plastic lens composition composed of two or more kinds of polymerizable monomers.
According to this, the raw material composition to be thermally polymerized is a thermosetting plastic lens composition composed of two or more polymerizable monomers, thereby obtaining a plastic lens having a stable polymerization quality. In addition, it is possible to obtain a deodorizing method for a polymerization furnace that can capture odor components such as hydrocarbon compounds generated during polymerization and can perform energy saving operation.

FIG. 1 is a schematic view of a polymerization furnace used in the deodorization method of the present invention.
In FIG. 1, the polymerization furnace 1 includes a polymerization furnace body 2, a temperature control device 3, a deodorization control device 4, and an operation unit 5.

  The polymerization furnace body 2 includes a heater 23 that heats the circulating air (atmosphere) in the furnace chamber 22, a radiator 24 that cools the circulating air in the furnace chamber 22, and a furnace chamber. A temperature sensor 25 for detecting the temperature of the circulating air 22, a fan 26 for circulating the air in the furnace chamber 22, and a mold W into which a polymerization composition to be thermally polymerized (hereinafter referred to as polymerization) is injected. A shelf 27 is provided. A desired number of molds W into which a thermosetting composition to be polymerized, which will be described later, is injected are placed on the shelf 27.

  Further, the heat insulating wall 21 is provided with an air intake port 28 through which external air outside the polymerization furnace main body 2 can be supplied to the furnace chamber 22 and an exhaust port 29 for exhausting the circulating air (atmosphere) in the furnace chamber 22. . An intake pipe 6 is connected and attached to the air intake port 28, and an intake damper 7 is provided on the flow path of the intake pipe 6. The intake damper 7 adjusts the opening degree of the intake damper 7 by the operation of the motor M <b> 3, and takes outside air outside the polymerization furnace 1 into the furnace chamber 22.

The temperature control device 3 includes a cooling device 31, a return pipe 32, a supply pipe 33, a heat medium temperature sensor 34, and a temperature control unit 35.
The cooling device 31 is a so-called direct (direct expansion) refrigerator that uses an HFC (hydrofluorocarbon) refrigerant called an alternative refrigerant as a heat medium, for example, as a heat medium, and performs heat exchange in the radiator 24 in the furnace chamber 22. The high-temperature gasified HFC refrigerant (refrigerant gas) is sucked through the return pipe 32, the sucked HFC refrigerant is cooled based on the control signal of the temperature control unit 35, and the cooled and liquefied (condensed) HFC The refrigerant is supplied (injected) to the radiator 24 through the supply pipe 33.

  The heat medium temperature sensor 34 is provided on the supply pipe 33, detects the temperature of the HFC refrigerant cooled in the cooling device 31 and circulated and supplied to the radiator 24, and sends the detected temperature value to the temperature control unit 35. Output.

  The temperature control unit 35 is a control means for controlling the heater 23, the fan 26, and the cooling device 31, and includes a temperature calculation unit 36 including a temperature PID (Proportional Integral Derivative) control controller and a memory, an inverter microcomputer, a memory, and the like. In addition, a temperature adjustment unit 37 that outputs an adjustment amount to the cooling device 31 and the heater 23 based on a control signal of the temperature calculation unit 36 is provided.

  The temperature calculation unit 36 detects the current detected temperature values in the control temperature sensor 25 and the heat medium temperature sensor 34 disposed in the furnace chamber 22, and a set temperature value (polymerization), which is stored in advance in the memory and is described later. The optimum PID value is calculated from the comparison calculation result with the temperature pattern. Then, a heating / cooling PID control signal based on the calculated PID value is output to the temperature adjustment unit 37. The temperature adjustment unit 37 was placed on the shelf 27 in the furnace chamber 22 by controlling the cooling device 31 and the heater 23 along the polymerization temperature pattern based on the control signal input from the temperature calculation unit 36. Polymerization (curing) of the mold W (raw material composition) is performed.

The deodorization control device 4 includes an exhaust pipe 41, an exhaust fan 42, an exhaust damper 43, an odor measuring device 44, a deodorization device 45, and a deodorization control unit 46.
The exhaust pipe 41 is connected to and attached to an exhaust port 29 provided in the heat insulating wall 21 of the polymerization furnace body 2, and functions as an exhaust passage for guiding the circulating air in the furnace chamber 22 to the exhaust fan 42. Have. An exhaust damper 43, an odor measuring device 44, and a deodorizing device 45 are arranged on the exhaust passage of the exhaust pipe 41.

  The exhaust fan 42 is rotated by the operation of the motor M2. The rotation of the exhaust fan 42 (motor M2) is controlled in frequency as the exhaust intensity based on the control signal of the deodorization control unit 46, and the circulating air (atmosphere) in the furnace chamber 22 is deodorized through the exhaust pipe 41. 4 and is deodorized by the deodorization control device 4, and then the amount of exhaust when being exhausted out of the furnace chamber 22 again through the exhaust pipe 41 is controlled.

  The exhaust damper 43 controls the exhaust amount of the circulating air in the furnace chamber 22 flowing into the exhaust pipe 41 by controlling the opening degree of the damper as the exhaust strength by the operation of the motor M3 based on the control signal of the deodorization control unit 46. To do. The intake damper 7 disposed on the flow path of the intake pipe 6 is adjusted to the same opening degree as the exhaust damper 43 in conjunction with the exhaust damper 43 by the operation of the motor M3 based on the control signal of the deodorization control unit 46. Then, the intake air amount control for taking in the outside air outside the polymerization furnace 1 into the furnace chamber 22 is performed.

  The odor measuring device 44 is, for example, an odor measuring device provided with a synthetic lipid bilayer quartz crystal sensor as an odor sensor, and an exhaust pipe 41 upstream of the exhaust damper 43 (between the exhaust port 29 and the exhaust damper 43). The odor intensity of the circulating air in the furnace chamber 22 at the time of polymerization is detected (measured). For the detection of the odor intensity, the odor intensity of a hydrocarbon compound or the like contained in the circulating air in the furnace chamber 22 is converted into a odor concentration as the degree of odor, and the numerical signal is output to the deodorization control unit 46. The odor measuring device 44 always measures the odor concentration of the circulating air in the furnace chamber 22 during the polymerization.

  The numerical value of odor concentration (degree of odor) is, for example, a value called CIAQ (Composite Index of Air Quality). Table 1 shows the correspondence between CIAQ and odor intensity (6-step odor intensity) in the Odor Control Law. Show.

表１に示すように、ＣＩＡＱ値は、臭気強度０（無臭）〜５（強烈な臭い）の６段階臭気強度に対応する０〜２００の値であり、例えば臭気強度２（何の臭いかが分かる）の値は、ＣＩＡＱとして２０〜２９の値に対応する。

As shown in Table 1, the CIAQ value is a value of 0 to 200 corresponding to a 6-step odor intensity of odor intensity 0 (no odor) to 5 (strong odor), for example, the odor intensity 2 (what odor is understood) ) Corresponds to a value of 20 to 29 as CIAQ.

  The deodorization device 45 is an adsorption-type deodorization device including, for example, a column filled with activated carbon. When the circulating air in the furnace chamber 22 passes through the column filled with activated carbon, the hydrocarbon type in which the charged activated carbon is contained in the circulating air. Adsorbs and captures odorous components such as compounds.

The deodorization control unit 46 is a control means for controlling the exhaust fan 42 and the exhaust damper 43 based on the odor concentration of the circulating air (atmosphere) in the furnace chamber 22 measured by the odor measuring device 44, and is a CPU (Central Processing Unit). ), An odor calculation unit 47 including a memory and the like, an inverter microcomputer, a memory, and the like, and output adjustment amounts to the exhaust fan 42 (motor M2) and the exhaust damper 43 (motor M3) based on the control signal of the odor calculation unit 47 An exhaust adjustment unit 48 is provided.
The operation unit 5 includes a number of operation switches (not shown), and inputs the type of raw material composition to be polymerized, the amount of the raw material composition, and the like. An input signal of the operation unit 5 is output to the deodorization control unit 46.

Next, thermal polymerization using the thus configured polymerization furnace will be described.
FIG. 2 is an explanatory cross-sectional view of a mold into which a raw material composition has been injected, and FIG. 3 is a diagram illustrating an example of a polymerization temperature pattern of the raw material composition.

First, the mold W into which a thermosetting composition (hereinafter may be referred to as a raw material composition) as a raw material composition to be polymerized is described.
In FIG. 2, the mold W has two glass molds 80 and 81 that form an optical surface of a lens having a desired curved surface fixed in advance with a jig at a predetermined interval for forming the lens. An adhesive tape 82 is wound and fixed around the side surfaces of the outer periphery of the sheet so as to straddle the two glass molds 80 and 81.
A thermosetting composition 83 to be polymerized is injected into the space between the two fixed glass molds 80 and 81 using, for example, a syringe.

The thermosetting composition 83 injected into the glass molds 80 and 81 is a plastic lens composition composed of two or more polymerizable monomers, and has a monofunctional or polyfunctional reactive group. , Having one or more radical polymerizable double bonds in the molecule, for example, epoxycidimethacrylate obtained by reacting bisphenol A diglycidyl ether and methacrylic acid, nonabutylene glycol dimethacrylate, benzyl methacrylate Urethane dimethacrylate obtained by reacting isophorone diisocyanate and 2-hydroxypropyl methacrylate is used. A thermopolymerization initiator, a release agent and the like can be added to the thermosetting composition 83.
The mold W into which the thermosetting composition 83 to be polymerized is injected is placed on the shelf 27 in the furnace chamber 22 of the polymerization furnace body 2 and is thermally polymerized.

Next, the polymerization temperature pattern of the thermosetting composition injected into the mold W will be described.
FIG. 3 is a diagram illustrating an example of the polymerization temperature pattern of the raw material composition, in which the vertical axis of the graph indicates the set temperature (° C.), and the horizontal axis indicates the elapsed time of polymerization.

  The mold W into which the thermosetting composition 83 has been injected is placed on a shelf 27 in the furnace chamber 22 of the polymerization furnace body 2 and, for example, at a temperature of about 30 ° C. based on the polymerization temperature pattern TP shown in FIG. 3 (a section shown in FIG. 3, that is, a constant low temperature section), and then heated up to about 120 ° C. (b section, that is, a temperature rising section), and held at about 120 ° C. for a certain time (c section, that is, constant high temperature) Section) Thermal polymerization. Thereafter, the temperature is lowered to a temperature close to room temperature (d section, ie, cooling section), the polymerized mold W is taken out from the furnace chamber 22, and the polymerization process is completed. The elapsed time of this polymerization process requires about 20 hours from when the mold W is put into the furnace chamber 22 (placed on a shelf) to when taken out.

  The temperature control based on the polymerization temperature pattern TP is performed in the temperature control device 3. In the temperature control, the temperature calculation unit 36 of the temperature control unit 35 calculates a deviation value from the current detected temperature value of the control temperature sensor 25 provided in the furnace chamber 22 and the polymerization temperature pattern (set temperature value) TP. Detecting and calculating the current optimum PID. The temperature adjustment unit 37 outputs an adjustment amount to the cooling device 31 and the heater 23 disposed in the furnace chamber 22 based on the control output from the temperature calculation unit 36, and the temperature is adjusted to follow the polymerization temperature pattern TP. Be controlled. Note that the fan 26 disposed in the furnace chamber 22 is rotated by the motor M1 over the entire period in which the thermosetting composition 83 is polymerized, and constantly circulates the air in the furnace chamber 22.

Next, a deodorizing method for the polymerization furnace in the polymerization will be described.
FIG. 4 is a diagram showing an example of the change over time in the odor concentration during polymerization of the raw material composition, and FIG. 5 is the exhaust intensity (power frequency applied to the exhaust fan and the opening degree of the exhaust damper) with respect to the odor concentration (CIAQ). It is a figure which shows an example of the control pattern of ().

When polymerizing the raw material composition, the odor concentration of the generated odor at the time of polymerization according to the raw material composition (thermosetting composition 83) to be polymerized in advance is measured.
The odor concentration of the raw material composition is measured by placing a predetermined number of molds W, into which the thermosetting composition 83 is injected, on a shelf 27 provided in the furnace chamber 22 of the polymerization furnace main body 2 to form a polymerization temperature pattern. The odor measuring device 44 measures the change over time in the odor intensity (odor concentration (CIAQ)) of the hydrocarbon-based compound or the like contained in the circulating air in the furnace chamber 22 when polymerized based on the odor. The measured odor concentration detection signal is output to the odor calculation unit 47 of the deodorization control unit 46. In the odor calculation unit 47, the change in the odor concentration with time is patterned into a calibration curve and stored in the memory as an odor concentration generation pattern.

  The time-dependent change in odor concentration shown in FIG. 4 is a diagram showing calibration curves of odor concentration measured in advance according to the amount (volume) of the raw material composition, and shows calibration curves in three different volumes. The vertical axis of the graph represents the odor concentration (CIAQ) value, and the horizontal axis represents the elapsed time of polymerization.

  The calibration curve SPA shown in FIG. 4 is an odor concentration generation pattern when the volume of the polymerized raw material composition is about 24 liters charged into the polymerization furnace 1 (furnace chamber 22 of the polymerization furnace body 2). Lines SPB and SPC are odor concentration generation patterns when the volume of the raw material composition is approximately 16 liters and approximately 8 liters.

  The volume of the thermosetting composition 83 injected into one mold W and polymerized is generally about 25 to 50 ml, and the volume of 24 liter shown in the calibration curve SPA is, for example, 34.3 ml. This corresponds to a case where 700 molds W into which the thermosetting composition 83 has been injected are put into the polymerization furnace 1.

  In FIG. 4, the odor concentration at the time of polymerization of the thermosetting composition 83 injected into the mold W changes over time along the polymerization temperature pattern TP shown in FIG. 3, and rises from a temperature of about 30 ° C. to about 120 ° C. In the initial stage of the section b to be heated, the odor concentration of the odor generated from the thermosetting composition 83 reaches a peak, and then gradually decreases. Further, the odor concentration of the odor generated from the thermosetting composition 83 shows a value substantially proportional to the volume of the thermosetting composition 83 to be polymerized, as shown by the three calibration curves SPA, SPB, SPC. Therefore, for each type of raw material composition, at least two types of odor concentration calibration curves with different volumes are measured, and proportional calculation is performed between the two calibration curves according to the volume of the raw material composition to be polymerized. Thus, for each type of raw material composition, it is possible to predict odor concentrations of various volumes to be polymerized.

In the polymerization furnace deodorization method in polymerization, a predicted pattern of odor concentration is calculated based on a pre-measured odor concentration generation pattern during polymerization, and the exhaust of the deodorization control device 4 corresponds to the odor concentration of the predicted pattern. The exhaust strength of the fan 42 and the exhaust damper 43 is controlled, and the circulating air in the furnace chamber 22 is deodorized. On the basis of so-called predictive control, the circulated air in the furnace chamber 22 is deodorized.
First, each type of data such as the type of raw material composition to be polymerized by being charged into the polymerization furnace, the model (ie, corresponding to the volume per mold W), and the quantity of the mold W is input from the operation switch of the operation unit 5. To do. An input signal of each input data is output to the deodorization control unit 46.

  In the deodorization control unit 46, the odor calculation unit 47 calculates the volume of the raw material composition based on the input signal of the model and the quantity of the mold W input from the operation unit 5. Then, based on the calculated volume and the input signal of the type of raw material composition input, from the generation pattern (calibration curve) of the odor concentration of three different volumes of the raw material composition stored in advance in the memory, A predicted pattern of odor concentration corresponding to the volume of the raw material composition to be polymerized is calculated. The calculated predicted pattern data is stored in the memory and is also sent to the exhaust adjustment unit 48 and stored in the memory.

  The exhaust adjustment unit 48 controls the power supply frequency (inverter control) of the exhaust fan 42 (motor M2) based on the prediction pattern stored in the memory, and controls the opening degree of the exhaust damper 43 (control of the motor M3). )I do. That is, the exhaust intensity of the exhaust fan 42 and the exhaust damper 43 is controlled, and the energy saving operation of the deodorization control device 4 is performed.

An example of the exhaust intensity control pattern with respect to the odor concentration (CIAQ) is shown in FIG.
The horizontal axis of the graph indicates the odor concentration value (CIAQ value), the right vertical axis indicates the frequency (Hz), and the left vertical axis indicates the degree of opening (%). A control pattern of a power supply frequency (hereinafter referred to as a frequency) applied to the exhaust fan 42 (motor M2) is denoted by α, and an opening degree adjustment pattern of the exhaust damper 43 is denoted by β. In addition, although the range of the frequency by which the exhaust fan 42 is controlled is 0 Hz (stop state) to 60 Hz (full operation state), the case of 0 to 50 Hz may be used when a commercial AC power supply is used.

  In FIG. 5, the frequency applied to the exhaust fan 42 is operated in the range of 0 to 60 Hz at a power supply frequency proportional to the odor concentration value. The frequency is 0 Hz (stop state) when CIAQ10, 30 Hz when CIAQ20, 60 Hz (full operation state) when CIAQ200, and when CIAQ is a value in the range of 20 to 200, it is proportional to the CIAQ value. Thus, it is operated at a frequency having a value on a line connecting 30 Hz and 60 Hz.

  Similarly, the opening degree of the exhaust damper 43 is adjusted within a range of 0 to 100% to an opening degree proportional to the odor concentration. The opening degree is adjusted to 0% (fully closed state) when CIAQ10, 15% when CIAQ20, 100% (fully open state) when CIAQ200, and when CIAQ is a value in the range of 20 to 200, CIAQ In proportion to the value, the opening degree on the line connecting 15% and 100% is adjusted.

  Then, when a polymerization start switch (not shown) is pressed and turned on, all the apparatuses in the polymerization furnace 1 are operated and placed on the shelf 27 in the furnace chamber 22 of the polymerization furnace main body 2 to be thermosetting. Polymerization of the mold W into which the composition has been injected starts.

  When the polymerization is started, the temperature is controlled by the temperature control device 3 based on the polymerization temperature pattern TP (see FIG. 3), and the odor concentration stored in the memory of the exhaust adjustment unit 48 is changed over time. Based on the predicted pattern, control of the power supply frequency of the exhaust fan 42 (motor M2) (inverter control) and control of the opening degree of the exhaust damper 43 (control of the motor M3) are performed.

  FIG. 6 is a diagram showing an example of a control pattern of the power supply frequency of the exhaust fan during polymerization of the raw material composition, where the horizontal axis of the graph indicates the elapsed time of polymerization and the vertical axis indicates the frequency (Hz). FIG. 7 is a diagram showing an example of the adjustment pattern of the opening degree of the exhaust damper during the polymerization of the raw material composition. The horizontal axis of the graph shows the elapsed time of polymerization, and the vertical axis shows the opening degree (%).

  The power frequency control patterns FTA, FTB shown in FIG. 6 and the exhaust damper opening degree adjustment pattern OT shown in FIG. 7 are, for example, when the volume of the raw material composition to be introduced into the polymerization furnace 1 and polymerized is approximately 24 liters. The case where it controls based on the prediction pattern of an odor density is illustrated. That is, the prediction pattern of the odor concentration is a pattern that is almost the same as the calibration curve SPA shown in FIG. The power frequency control pattern FTB shown in FIG. 6 shows a case where the power frequency is controlled by general inverter control based on the odor concentration prediction pattern for comparison and confirmation.

  The control of the power supply frequency of the exhaust fan 42 is based on the prediction pattern of odor concentration (see the calibration curve SPA shown in FIG. 4) and the control pattern α of the power supply frequency (see FIG. 5) stored in the memory in the exhaust adjustment unit 48. Thus, the power supply frequency corresponding to the value of the odor concentration that changes with the elapsed time of polymerization is output to the exhaust fan 42 (motor M2), and rotates at a rotational speed corresponding to the power supply frequency.

  The control pattern FTA of the power supply frequency for controlling the exhaust fan 42 at the time of polymerization is controlled to about 40 Hz immediately after the start of polymerization, about 55 Hz at about CIAQ 190 when the odor concentration reaches a peak, and about 40 Hz just before the end of the polymerization. As shown in FIG. 6, the power supply frequency control pattern FTA for controlling the exhaust fan 42 is controlled at a frequency lower by about 10% than the power supply frequency control pattern FTB by general inverter control.

  The control of the opening degree of the exhaust damper 43 is performed by the exhaust adjustment unit 48 based on the odor concentration prediction pattern stored in the memory and the opening degree control pattern β (see FIG. 5). A control voltage corresponding to the value is output to the motor M3, and the motor M3 operates by an adjustment amount corresponding to the control voltage, so that the opening degree of the exhaust damper 43 is controlled.

  As shown in FIG. 7, the adjustment pattern OT of the opening degree of the exhaust damper 43 controlled at the time of polymerization changes substantially along the predicted odor concentration pattern SPA, and is approximately 95% at approximately CIAQ 190 when the odor concentration reaches a peak. The degree of opening is controlled.

  When the exhaust fan 42 and the exhaust damper 43 are operated based on the control of the exhaust adjustment unit 48, the circulating air in the furnace chamber 22 is guided to the deodorizing device 45 including the activated carbon filling tower via the exhaust pipe 41, and the activated carbon filling tower. When passing through, activated carbon adsorbs and captures odorous components such as hydrocarbon compounds contained in the circulating air. The circulating air from which the odor component is captured and deodorized in an odorless state is exhausted to the external environment outside the polymerization furnace 1 through the exhaust pipe 41 again.

  Further, the odor calculating unit 47 calculates the current value (CIAQ value) of the odor concentration of the circulating air in the furnace chamber 22 measured by the odor measuring device 44 and the odor concentration value of the predicted pattern (that is, the predicted value (CIAQ value)). When the value exceeds a predetermined range, an instruction signal for correcting the exhaust intensity is output to the exhaust adjustment unit 48. The predetermined range is a range of variation in odor concentration at the time of polymerization of the raw material composition, for example, a value of about ± 15% of a predicted value. In addition, when the difference between the current value of the odor concentration and the predicted value exceeds the predetermined range, the amount of additives added to the raw material composition to be polymerized is added in an amount different from the normal amount added. Or the case where a malfunction generate | occur | produces in a part of apparatus which comprises the polymerization furnace 1 etc. is assumed.

  When the instruction signal for correcting the exhaust intensity is input, the deodorizing control unit 46 switches to control for correcting the exhaust intensity of the exhaust fan 42 and the exhaust damper 43. The control for correcting the exhaust intensity is so-called ON / OFF control.

The deodorization control unit 46 determines that the current value of the odor concentration (CIAQ) measured by the odor measuring instrument 44 is a value exceeding + 15% of the predicted value, and the absolute value of the value exceeding + 15% is 20 or more. Then, the power supply frequency of 60 Hz is output to the exhaust fan 42 (motor M2), the exhaust fan 42 is fully rotated, and the exhaust damper 43 (motor M3) is fully opened (opening degree 100%).
On the other hand, when the current value of the odor concentration (CIAQ) is less than −15% of the predicted value and the absolute value of the value less than −15% is 20 or more, the output is output to the exhaust fan 42 (motor M2). The power supply frequency to be stopped is stopped, the exhaust fan 42 is stopped, and the exhaust damper 43 (motor M3) is fully closed (opening degree 0%).

The amount of electric power of the deodorization control device in the polymerization operated by the above deodorization method of the polymerization furnace will be described.
FIG. 8 is a graph showing the transition of the amount of electric power used by the deodorization control device 4 (exhaust fan 42) during polymerization of the raw material composition. The horizontal axis of the graph indicates the elapsed time of polymerization, and the vertical axis indicates the electric energy ( Watts (W)). The amount of power is the total amount of power used by the exhaust fan 42 and the exhaust damper 43, and is a transition in which the amount of power every five minutes of the elapsed time of polymerization is plotted.

  In addition, the transition line ETa of the electric energy shown in the figure shows the transition in the deodorization control device 4 in which the exhaust intensity control of the exhaust fan 42 and the exhaust damper 43 in the present embodiment, that is, the so-called predictive control is performed. The transition line ETb and the transition line ETc are shown for comparison, when the power supply frequency of the exhaust fan 42 is experimentally controlled by a general inverter experimentally using the deodorization control device 4 of the present embodiment. It shows the transition of the electric energy when the operation is performed at a constant power frequency of 60 Hz that is not controlled. It should be noted that the transition lines ETb and ETc of the electric energy are only controlled for the power supply frequency of the exhaust fan 42, and are not controlled for the opening degree of the exhaust damper 43 and the intake damper 7, but are maintained in the fully opened state. Indicates the amount.

  The amount of power used by the deodorization control device 4 changes according to the control pattern of the power supply frequency at the time of polymerization. As shown in FIG. 8, the transition line ETa on which the predictive control is performed is subjected to general inverter control. Compared with the transition line ETb and the transition line ETc that is operated at a constant power supply frequency, an efficient energy-saving operation can be obtained with a lower power consumption.

  The amount of electric power used by the deodorization control device 4 by controlling each power source frequency was measured. The measured value is the monthly average power consumption of 10 polymerization furnaces equipped with the deodorization control device 4, and the power consumption when operated at a constant power supply frequency is 8,500 kwh / month. The amount of power when the operation was performed was 4,900 kwh / month, and the amount of power when the power supply frequency prediction control was performed was 3,880 kwh / month. The deodorizing method for the polymerization furnace in which the power supply frequency prediction control is performed can reduce the amount of power by about 20 to 55% compared to the conventional method.

  According to the above embodiment, the deodorization control apparatus 4 exhausts the atmosphere in the polymerization furnace 1 according to the predicted pattern based on the generation pattern of the odor concentration generated during the thermal polymerization of the raw material composition measured in advance. The exhaust intensity of the exhaust fan 42 and the exhaust damper 43 is controlled, and the exhaust intensity of the exhaust fan 42 and the exhaust damper 43 is corrected when the odor concentration detected by the odor measuring device 44 exceeds a predetermined range of the predicted pattern. By performing the control, a deodorizing method for the polymerization furnace 1 is obtained that can remove odors generated during thermal polymerization of the raw material composition by energy saving operation without consuming unnecessary electric power.

In the above embodiment, the description has been given of the case where the deodorizing device 45 is an adsorption-type deodorizing device including an activated carbon-filled tower. However, even in the case of an ozone oxidation method or a photocatalyst deodorizing device, the activated carbon-filled tower is used. Similarly to the adsorption system consisting of the above, a deodorizing method for the polymerization furnace in which energy saving operation is achieved can be obtained by predictive control of the exhaust strength of the exhaust fan and exhaust damper.
Further, the temperature control device 3 includes the temperature control unit 35 and the deodorization control device 4 includes the deodorization control unit 46. However, the temperature control unit 35 and the deodorization control unit 46 are configured as a single control unit. Also good.

Moreover, although the direct type (direct expansion type) refrigerator was used for the cooling means, an indirect type (indirect expansion type) refrigerator may be used.
Also, the polymerization temperature pattern TP for the polymerization of the mold W injected with the thermosetting composition shown in FIG. 3 depends on the desired thermosetting composition to be polymerized, and is not limited to this. It may be a case of a thermosetting composition.

  Further, the thermosetting composition may be any composition in any combination as long as it is a composition for plastic lenses composed of two or more kinds of polymerizable monomers. The fixing of the two glass molds 80 and 81 constituting the mold W into which the thermosetting composition is injected has been described in the case of the configuration using the pressure-sensitive adhesive tape coated with the pressure-sensitive adhesive. The structure using the gasket currently used may be sufficient.

The schematic diagram of the polymerization furnace used for the deodorizing method of this invention. Cross-sectional explanatory drawing of the mold in which the raw material composition was inject | poured. The figure which shows an example of the polymerization temperature pattern of a raw material composition. The figure which shows an example of the time-dependent change of the odor density | concentration at the time of superposition | polymerization of a raw material composition. The figure which shows an example of the control pattern of the exhaust strength with respect to an odor density | concentration. The figure which shows an example of the control pattern of the power supply frequency of an exhaust fan at the time of superposition | polymerization of a raw material composition. The figure which shows an example of the adjustment pattern of the opening degree of an exhaust damper at the time of superposition | polymerization of a raw material composition. The figure which shows transition of the electric power consumption of the deodorizing control apparatus at the time of superposition | polymerization of a raw material composition.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Polymerization furnace, 2 ... Polymerization furnace main body, 3 ... Temperature control apparatus, 4 ... Deodorization control apparatus, 5 ... Operation part, 6 ... Intake pipe, 7 ... Intake damper, 21 ... Heat insulation wall, 22 ... Furnace chamber, 23 ... Heater, 24 ... Radiator, 25 ... Temperature sensor for control, 26 ... Fan, 27 ... Shelf, 28 ... Air intake port, 29 ... Exhaust port, 31 ... Cooling device, 32 ... Return pipe, 33 ... Supply pipe, 34 ... Heat Medium temperature sensor 35 ... Temperature control unit 36 ... Temperature calculation unit 37 ... Temperature adjustment unit 41 ... Exhaust pipe as exhaust passage, 42 ... Exhaust fan, 43 ... Exhaust damper, 44 ... Odor measuring device, 45 ... Deodorizing device, 46 ... deodorizing control unit, 47 ... odor calculating unit, 48 ... exhaust adjusting unit, 80, 81 ... glass mold, 82 ... adhesive tape, 83 ... thermosetting composition as raw material composition, W ... mold, TP ... Polymerization temperature pattern, SPA, SPB, SPC ... Odor concentration The generation pattern (calibration curve), FTA, FTB ... power supply frequency of the control pattern, OT ... adjusting pattern of the opening degree of the exhaust damper, the control pattern of the alpha ... power frequency, beta ... adjusting pattern of the opening degree of the exhaust damper.

Claims (4)

A deodorizing method for a polymerization furnace for thermally polymerizing a raw material composition,
The polymerization furnace is
An exhaust fan for exhausting the atmosphere in the polymerization furnace;
An exhaust passage for guiding the atmosphere in the polymerization furnace to the exhaust fan;
An exhaust damper for controlling an exhaust amount of the atmosphere flowing through the exhaust passage on the exhaust passage with an opening degree;
An odor measuring device for detecting an odor concentration in the polymerization furnace on the exhaust passage upstream of the exhaust damper;
A deodorizing device for removing odors contained in the atmosphere on the exhaust flow path downstream of the exhaust damper;
An odor control unit that controls exhaust strength of the exhaust fan and the exhaust damper based on the odor concentration detected by the odor measuring device;
With
The odor control unit is
Calculate the predicted pattern of odor concentration based on the odor concentration generation pattern generated during the thermal polymerization of the raw material composition measured in advance,
While controlling the exhaust intensity according to the calculated prediction pattern of the odor concentration,
A deodorizing method for a polymerization furnace, wherein control is performed to correct the exhaust gas intensity when an odor concentration detected by the odor measuring device exceeds a predetermined range of the predicted pattern.   2. The deodorization method for a polymerization furnace according to claim 1, wherein the exhaust intensity is controlled by controlling the frequency of the operation of the exhaust fan and controlling the opening degree of the exhaust damper. 3.   The said prediction pattern is calculated corresponding to the volume value of the said raw material composition thrown in in the said polymerization furnace based on the generation pattern of the said odor density | concentration measured beforehand. The deodorizing method of the polymerization furnace as described. The method for deodorizing a polymerization furnace according to any one of claims 1 to 3, wherein the raw material composition is a composition for plastic lenses composed of two or more kinds of polymerizable monomers.

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