JP4182934B2 - Primary air supply device for rotary stoker incinerator - Google Patents

Description

  The present invention supplies primary air from the wind box to the upstream portion of the furnace in order to dry the object in the stoker furnace body when the object to be processed such as municipal waste is incinerated in the rotary stoker incinerator. Thus, the present invention relates to a primary air supply device.

  As one of the devices for incineration of wastes to be treated, by rotating the cylindrical stalker furnace body, waste can be efficiently incinerated while continuously and three-dimensionally feeding and stirring. A rotary stoker incinerator is known.

  In such a rotary stoker type incinerator, as shown in FIGS. 4 (a), (b) and (c), a large number of water pipes 4 are placed between an inlet side header pipe 2 and an outlet side header pipe 3 formed in a ring shape. The both ends of the water pipes 4 are connected in communication with the header pipes 2 and 3 on the inlet side and the outlet side, and are disposed in the gaps between the water pipes 4 in the longitudinal direction. The stoker furnace main body 1 is formed by attaching a fin 7 having a large number of air holes 6 at a required interval and molding it into a cylindrical shape. Further, the stoker furnace main body 1 is placed in the cover casing 8 so as to be inclined so that the outlet side header pipe 3 is lower than the inlet side header pipe 2, and is placed on the outer periphery of the inlet side and the outlet side ends. The attached tires 9 are respectively placed on the turning rollers 10, and the turning rollers 10 are rotated by a driving device 11, so that the stalker furnace body 1 is rotationally driven. Further, boiler water is circulated in each water pipe 4 through a rotary joint 12 connected to the outlet-side header pipe 3. Further, the waste 14 in the charging hopper 13 is supplied to the stalker furnace main body 1 from the inlet side by a dust feeder 15, while the lower position of the stalker furnace main body 1 has a cover. An air box 16 communicating with the lower end of the casing 8 is provided, and primary air 5 is supplied from the lower position of the stoker furnace body 1 into the furnace through the air holes 6.

  The wind box 16 is divided into a plurality of, for example, three parts in the longitudinal direction (downstream of the furnace) of the stoker furnace main body 1, and from the upstream, the furnace upstream wind box 17a, the furnace intermediate wind box 17b, and the furnace downstream. A side wind box 17c is provided. The furnace upstream wind box 17a, the furnace intermediate wind box 17b, and the furnace downstream wind box 17c are each provided with a damper 18, and the supply amount of the primary air 5 is adjusted by adjusting each damper 18, respectively. is there. Further, in the furnace upstream wind box 17a, the furnace intermediate wind box 17b, and the furnace downstream wind box 17c, as shown in FIG. , 19c are divided into three parts, and each of the circumferentially divided flow paths 19a, 19b, 19c is also provided with a damper 18, and the periphery of the waste 14 staying at the furnace bottom of the stoker furnace body 1 is provided. The supply amount of the primary air 5 can be adjusted according to the amount of the direction.

  A seal device 20 is attached to each of the circumferential flow division channels 19a, 19b, and 19c of the wind boxes 17a, 17b, and 17c near the stalker furnace body 1, and each water pipe 4 of the stalker furnace body 1 is attached. The sealing fins 21 attached to the outer side of the main body 5 rotate and come into contact with the respective sealing devices 20 to perform a sealing action, and the primary air 5 supplied from the circumferential divided flow paths 19a, 19b, 19c. However, it is made to blow in the corresponding part of the furnace bottom part of the stoker furnace main body 1. FIG.

  According to the rotary stoker-type incinerator having such a configuration, when the waste 14 is supplied from the dust feeder 15 into the stalker furnace main body 1 in the state where the stalker furnace main body 1 is rotated at a low speed by the driving device 11, Since the supplied waste 14 always tries to fall to the bottom of the furnace due to its own weight, it is agitated with the rotation of the stalker furnace body 1 and is sequentially transferred to the downstream side of the furnace by the inclined arrangement of the stalker furnace body 1. During this transfer, the primary air 5 supplied from the furnace upstream wind box 17a, the furnace intermediate wind box 17b, and the furnace downstream wind box 17c in the wind box 16 installed on the lower side from the furnace upstream side. It is incinerated through the processes of drying, pyrolysis, and combustion.

  That is, the waste 14 supplied into the stalker furnace main body 1 is first subjected to a required temperature supplied mainly from the furnace upstream wind box 17a in the drying zone 1a formed in the upstream part of the furnace, for example, 200 ° C. It is made to dry by exposing to the primary air 5 and the high temperature atmosphere in a furnace. Next, the dried waste 14 is transferred to the thermal decomposition zone 1b formed in the furnace middle part, where the primary air 5 is supplied from the furnace middle wind box 17b, and the downstream combustion zone 1c is supplied. Combustion heat generated in this way is burned as a heat source and pyrolyzed. Thereafter, the pyrolyzate is transferred to the combustion zone 1c formed in the downstream portion of the furnace and combusted using the primary air 5 supplied from the downstream wind box 17c for incineration. It is supposed to be. In the figure, 22 is a secondary combustion chamber, and 23 is a post-combustion device (see, for example, Patent Document 1).

  By the way, when incineration of the waste 14 is performed in the rotary stoker type incinerator, the thickness of the waste layer staying at the bottom of the stoker furnace body is determined by the lengthwise drying and heat of the stoker furnace body 1. If it fluctuates in each zone 1a, 1b, 1c of decomposition or combustion, or fluctuates in the circumferential direction, the burn-out point moves and stable combustion cannot be performed. For this purpose, the flow rate and pressure of the primary air supplied to each wind box 17a, 17b, 17c in the upstream / downstream direction of the wind box 16 are measured, and the correlation between the measured flow rate and pressure and the layer thickness of the waste 14 is measured. From the relationship, the layer thickness of the waste layer at the bottom of the furnace existing above each wind box 17a, 17b, 17c in the longitudinal direction is estimated, and each wind in the longitudinal direction is estimated according to the estimated layer thickness. It has been conventionally proposed to adjust the distribution ratio of the primary air 5 to the boxes 17a, 17b, 17c. Further, in the same manner as in the case of the longitudinal wind boxes 17a, 17b, and 17c, the circumferential division channels 19a, 19b, and 19c of the longitudinal wind boxes 17a, 17b, and 17c are supplied. It has also been proposed to detect the layer thickness from the flow rate and pressure of the primary air 5 and to control the distribution ratio of the primary air 5 according to the detected layer thickness (see, for example, Patent Document 2). ).

Japanese Patent Laid-Open No. 11-257616 JP 2000-291928 A

  However, according to recent research, when incineration of waste 14 having a high water content is performed in a rotary stoker type incinerator as shown in FIGS. It has been found that a significant portion of one furnace length, up to about half of the furnace length, is spent as the drying zone 1a for the high water content waste 14 introduced. That is, when the waste 14 having a high water content is to be treated, it is necessary to lengthen the drying time. In order to take a long time for drying as described above, the outlet side of the stoker furnace body 1 is low. In this way, the waste 14 is sequentially transferred to the downstream side of the furnace by rotation, so that the furnace length must be increased. Therefore, it is desired to improve the drying efficiency of the waste 14 in the upstream portion of the furnace that becomes the drying zone 1a of the stoker furnace body 1.

  In the conventional rotary stoker-type incinerator shown in FIGS. 4 (a), 4 (b), and 4 (c), the waste 14 layer that is supplied into the stoker furnace body 1 and stays at the bottom of the furnace is the stoker furnace body 1 described above. Is formed in a cylindrical shape, the both end portions in the circumferential direction of the stoker furnace main body 1, that is, the thickness of the both end portions in the width direction of the waste layer is thinner than the central portion in the width direction. The amount of the waste 14 existing at both ends in the width direction of the layer is relatively smaller than that in the center portion in the width direction. However, in the drying zone 1a of the upstream portion of the stoker furnace body 1, the supplied high moisture content waste 14 is used by using the primary air 5 supplied from the furnace upstream wind box 17a in the wind box 16. At the time of drying, both ends in the width direction of the waste layer in the drying zone 1a are ventilated from the divided flow paths 19a and 19c in the circumferential direction of the furnace upstream wind box 17a at the corresponding lower position, respectively. The ventilation is equivalent to the ventilation from the circumferential divided flow path 19b corresponding to the central portion in the width direction of the waste layer having a relatively thick layer, or in the divided flow paths 19a and 19c, Since the layer thickness of the waste 14 existing on the upper side is relatively thinner than the central portion in the width direction of the waste layer, and the pressure loss is reduced, the ventilation of the divided flow path 19b or more is performed.

  For this purpose, the primary air 5 supplied from the divided flow paths 19a and 19c on both sides in the circumferential direction of the furnace upstream wind box 17a to both ends in the width direction of the waste layer having a thin layer thickness passes through the waste layer. The actual situation is that the time required to do so, that is, the residence time in the waste layer is short, and the ratio of exhausted from the waste layer is increased without fully utilizing the drying capacity that is held. For this reason, the exhaust amount of the primary air 5 in the drying zone 1a of the stoker furnace main body 1 becomes excessive, the exhaust gas treatment facility increases due to the increase in the exhaust gas amount, the exhaust gas temperature decreases and is discarded. There is a concern that clinker may be easily generated due to early ignition at both ends in the width direction of the material layer.

  Furthermore, since the stoker furnace main body 1 is a welded structure with a large diameter, it is difficult to produce a perfect circle with high accuracy, and there is a slight swing of the rotating shaft. It is difficult to perform a complete sealing action by the contact between the sealing device 20 provided in the position close to the stalker furnace body 1 of the divided flow paths 19a, 19b, 19c and the sealing fin 21 on the stalker furnace body 1 side. In the divided flow paths 19a and 19c on both sides in the circumferential direction of the furnace upstream wind box 17a, the primary air 5 to be blown from the furnace bottom of the stoker furnace main body 1 tends to leak toward the cover casing 8, and this also causes waste. There is also a concern that the exhaust amount of the primary air 5 supplied to perform the drying of 14 increases.

  In addition, in what was described in patent document 2, the furnace upstream side wind box 17a, the furnace intermediate part wind box 17b, the furnace downstream side wind box 17c in the stoker furnace main body 1, and the division | segmentation flow path 19a of each circumferential direction in it Depending on the layer thickness of the waste 14 existing above 19b, 19c, the distribution ratio of the primary air 5 to be supplied is different for each wind box 17a, 17b, 17c or each divided flow path 19a, 19b, 19c. This is to prevent the burning point from moving in the stalker furnace body 1 and causing unstable combustion, and the drying zone 1a of the stalker furnace body 1 is adjusted. When the waste 14 is dried using the primary air 5 in the upstream portion of the furnace, the amount of the primary air 5 that passes through the waste layer and is exhausted without fully utilizing the drying capacity that is held is reduced. For ideas Not Ku shown. In addition, when adjusting the distribution ratio of the primary air 5 in the circumferential divided flow paths 19a, 19b, 19c in accordance with the layer thickness of the waste 14, a part of the divided flow paths 19a, 19b, 19c is used. The idea of stopping the supply of the primary air 5 is not shown or suggested at all.

  Therefore, the present invention is to dry the object to be treated to be incinerated by primary air blown from the wind box at the upstream end which is the drying zone of the stoker furnace body in the rotary stoker incinerator. Extending the time required for the primary air used for the drying to pass through the layer of the object to be processed, the proportion of the drying capacity of the primary air that contributes to the drying of the object to be processed is In order to provide a primary air supply device for a rotary stoker type incinerator that can be increased in size, can improve the drying efficiency of waste, and can reduce the amount of primary air used for drying of waste. To do.

In order to solve the above-mentioned problem, the present invention, corresponding to the invention according to claim 1, supplies a workpiece to be supplied from an upstream side to a stoker furnace body that is horizontally placed in a rotatable manner. While being transported to the downstream side while being stirred by rotation, the primary air supplied from the wind box is incinerated by drying, pyrolysis, and combustion through the primary air to the upstream side of the rotary stoker incinerator. The air box for supplying air has a large number of ventilation areas subdivided in the circumferential direction of the stoker furnace body, and an air supply line that guides primary air from the blower to each of the subdivided ventilation areas. In addition, an on- off valve is provided for each ventilation region, and the amount of primary air supplied to the wind box on the upstream side of the furnace is used to dry the workpiece in the upstream part of the furnace, which becomes the drying zone of the stoker furnace body. To set in advance Or the primary air pressure supplied to the wind box upstream of the furnace is lower than the primary air pressure necessary to obtain the target ventilation rate. when, a structure in which to be able to go to close the opening and closing valve per each vent region in the circumferential direction suited et order.

  Further, the wind box for supplying primary air to the upstream side of the furnace according to the first aspect of the invention is configured to be subdivided into four or more ventilation regions in the circumferential direction of the stoker furnace main body.

In the above configuration, it provided the circumferential pressure gauge for detecting the pressure of the flow meter or the primary air to detect the total ventilation amount of primary air supplied to each of the ventilation region of the air feed line, flow meter or et input It is determined whether the total ventilation volume is larger than the target ventilation volume based on the received signal , or the measured value of the pressure gauge and the target ventilation volume at that time based on the signal input from the pressure gauge It is set as the structure provided with the control apparatus which compares with the pressure at the time of making it, and gives the opening / closing command to the opening / closing valve for each said ventilation area | region.

According to the primary air supply device of the rotary stoker type incinerator of the present invention, the following excellent effects are exhibited.
(1) The primary material supplied from the wind box while the workpiece supplied from the upstream side to the stalker furnace main body, which is horizontally placed in a rotatable manner, is transferred to the downstream side while being stirred by the rotation of the stalker furnace main body. A large number of wind boxes that supply primary air to the upstream side of a rotary stoker type incinerator that is designed to be incinerated through the process of drying, pyrolysis, and combustion with air, which are subdivided in the circumferential direction of the stoker furnace body. An air supply line that has a ventilation area and that guides primary air from the blower to each of the subdivided ventilation areas is provided with an open / close valve for each ventilation area, to the wind box upstream of the furnace. It is determined that the total ventilation rate of the supplied primary air is larger than the target ventilation rate that is set in advance to dry the workpiece in the furnace upstream portion that becomes the drying zone of the stoker furnace body. Or above Primary air pressure supplied to the upstream windbox is lower than the pressure of the primary air required for obtaining the target amount of aeration go close in sequence the opening and closing valve per each vent region from circumferential Direction a structure in which to be able, region further, specifically, to perform since a structure in which to have four or more vent region in the circumferential direction of the stoker furnace body, blowing primary air in the furnace upstream Can be limited to the central portion of the furnace upstream wind box. As a result, the primary air can be blown in the central portion in the width direction where the layer thickness is thick with respect to the layer of the object to be processed that is retained in the furnace upstream portion of the stoker furnace main body. The time required for the blown primary air to pass through the layer to be processed can be extended.
(2) Therefore, the primary air blown into the layer of the object to be processed has a larger proportion of the drying capacity that it contributes to drying of the object to be processed as compared with the prior art. In the drying zone in the upstream portion of the furnace, the object to be processed can be efficiently dried with a smaller amount of primary air as compared with the prior art. For this reason, it is possible to reduce the amount of primary air that is blown from the furnace upstream side air box and used to dry the object to be processed in the stoker furnace body as compared with the conventional case.
(3) Accordingly, the amount of exhaust gas can be reduced, and the exhaust gas treatment device can be downsized. In addition, it is possible to suppress the occurrence of a decrease in the exhaust gas temperature that leads to the generation of dioxins and the occurrence of clinker due to early ignition at both ends in the width direction of the waste layer due to a decrease in the primary air flow rate. Furthermore, by improving the drying efficiency of the object to be processed, the furnace length of the stoker furnace body can be shortened, and it can be expected to contribute to the miniaturization of the entire plant.
(4) A flow meter for detecting the total ventilation amount of the primary air supplied to each ventilation region of the wind box upstream of the furnace or a pressure gauge for detecting the pressure of the primary air is provided in the air supply line, and the flow meter or pressure the configuration and be Rukoto having a control device on the basis of a signal input from the meter gives a switching command to the on-off valve per each vent region, at a furnace upstream of the stoker body of the furnace upstream windbox under The area where primary air is blown from the furnace upstream wind box in a state in which the desired primary air flow rate is secured to dry the processed material is as narrow as possible near the center of the furnace upstream wind box. It can be automatically controlled.

  The best mode for carrying out the present invention will be described below with reference to the drawings.

  FIGS. 1 to 3 (a), (b), and (c) show an embodiment of the primary air supply device of the rotary stoker type incinerator of the present invention. In the same manner as shown, the stoker furnace main body 1 having a water pipe wall structure is laid horizontally in the cover casing 8 so that the waste 14 as the object to be treated supplied from the inlet side is disposed in the stoker furnace main body 1. While being agitated by rotation, it is sequentially transferred to the downstream side of the furnace, and during this transfer, the furnace upstream side wind box 17a, the furnace intermediate part wind box 17b, which constitutes the wind box 16 located below the stoker furnace main body 1, the downstream of the furnace The furnace upstream side wind box 17a in the rotary stoker type incinerator in which the waste 14 is incinerated through the process of drying, pyrolysis, and combustion with the primary air 5 supplied from the side wind box 17c, Three conventional divisions divided in the circumferential direction of the main body 1 Road 19a, 19b, more than 19c, namely, the circumferential direction divided passages 24a as aeration area subdivided four or more in the circumferential direction, 24b, 24c, 24d, a structure having 24e. Further, downstream end portions of the air supply line 26 for guiding the primary air 5 from the blower 25 are branched to the circumferentially divided flow paths 24a, 24b, 24c, 24d, and 24e to branch lines 26a and 26b. , 26c, 26d, and 26e, and the branch lines 26a, 26b, 26c, 26d, and 26e are each provided with an on-off valve 27, and the subdivided circumferential divided flow paths 26a, 24b, 24c, and 24d are provided. , 24e are closed in order from the outside within the capacity range of the blower 25 so that the primary air 5 can be supplied.

A flow meter 28 for measuring the amount of primary air 5 (total ventilation) supplied to the whole furnace upstream wind box 17a is provided at a position upstream of the branch point of the air supply line 26. It is.
Further, a pressure gauge 29 for measuring the pressure of the primary air 5 supplied to the whole furnace upstream wind box 17a is also provided.

  Further, a control device 30 is provided for giving an open / close command to the open / close valve 27 on each branch line 26a, 26b, 26c, 26d, 26e based on a signal input from the flow meter 28. Other configurations are the same as those shown in FIGS. 4A, 4B, and 4C, and the same components are denoted by the same reference numerals.

  The control device 30 is configured as shown in a control flow in FIG. In a state in which the blower 25 is rated and the operation of the rotary stoker incinerator is started, first, based on the signal input from the flow meter 28, the furnace upstream wind box 17a through the air supply line 26. The total aeration amount of the primary air 5 supplied to all the divided flow paths 24a, 24b, 24c, 24d, and 24e is periodically measured at predetermined time intervals (step 1: S1).

  Next, the measured value of the total aeration amount of the primary air 5 is a desired aeration amount (preliminarily set for drying the waste 14 in the upstream portion of the furnace that becomes the drying zone 1a of the stoker furnace body 1 ( Hereinafter, it is determined whether or not it is larger than the target ventilation amount (step 2: S2).

  If it is determined in step 2 that the measured value of the total ventilation rate of the primary air 5 is larger than the target ventilation rate, each circumferentially divided flow path of the furnace upstream side wind box 17a. Out of the circumferentially divided flow paths in ventilation at 24a, 24b, 24c, 24d, and 24e, the circumferentially divided flow paths on both sides located on the outermost side, for example, as shown in FIG. When the flow paths 24a, 24b, 24c, 24d, and 24e are ventilating, as shown in FIG. 3B, on the branch lines 26a and 26e connected to the circumferentially divided flow paths 24a and 24e on both sides. The on / off valve 27 is commanded to be closed, and the ventilation to the circumferentially divided flow paths 24a and 24e is stopped (step 3: S3).

  Thus, when the ventilation from the circumferentially divided flow channels 24a and 24e located on the outermost side among the circumferentially divided flow channels 24a, 24b, 24c, 24d, and 24e that have been ventilated is stopped, The ventilation of the primary air 5 is limited to the circumferentially divided flow paths 24b, 24c and 24d closer to the center. Thereby, since the width | variety of the area | region which blows the primary air 5 in the furnace upstream side part used as the drying zone 1a of the stoker furnace main body 1 from the said furnace upstream wind box 17a becomes narrow, the primary air 5 stays in a furnace bottom part. Among the waste layers, the waste layers are concentrated and supplied to the thick central portion in the width direction. At the same time, the pressure loss of the supplied primary air 5 increases as the blowing area of the primary air 5 is restricted to the central portion in the width direction of the waste layer having a thick layer thickness. The air flow decreases (step 4: S4).

  Therefore, after returning to Step 1 again and measuring the total ventilation rate of the primary air 5, the measured value of the total ventilation rate is compared with the target ventilation rate in Step 2. When the total ventilation amount measurement value is larger than the target ventilation amount, in step 3, as shown in FIG. 3C, among the circumferentially divided flow paths 24b, 24c, and 24d during ventilation, By closing the on-off valve 27 on the branch lines 26b and 26d connected to the circumferentially divided flow paths 24b and 24d on both sides located on the outermost side, ventilation to the circumferential divided flow paths 24b and 24d is performed. Thus, the ventilation of the primary air 5 is limited only to the central width-direction divided flow path 24c. Thereby, the width | variety of the area | region which blows the primary air 5 in the furnace upstream side part used as the drying zone 1a of the stoker furnace main body 1 from the said furnace upstream wind box 17a becomes still narrower, and the primary air 5 stays in a furnace bottom part. Among the waste layers that are present, the waste layers are concentratedly supplied only to the central portion in the width direction where the layer thickness is large. At the same time, the pressure loss of the supplied primary air 5 further increases as the blowing area of the primary air 5 is limited only to the central portion in the width direction of the waste layer having a thick layer thickness. The total aeration amount of the gas further decreases (step 4: S4).

  On the other hand, by the step 3, the outermost circumferential divided flow paths 24a and 24e among the circumferential divided flow paths 24a, 24b, 24c, 24d and 24e being ventilated in the furnace upstream wind box 17a (FIG. 3 ( B)), or, as shown in step 4, the total primary air 5 is increased by stopping the supply of the primary air 5 to 24b and 24d (see FIG. 3 (c)). When it is determined that the total ventilation amount measurement value of the primary air 5 measured by returning to Step 1 is not larger than the target ventilation amount in Step 2 when the ventilation amount decreases, or In this way, the primary air 5 is supplied in such a way that the central divided circumferential flow paths 24b, 24c, 24d (see FIG. 3 (b)) or only 24c (see FIG. 3 (c)) in the furnace upstream wind box 17a. Restricted to Thus, the change in the waste quality of the waste 14 supplied to the stoker furnace main body 1 causes an increase in pressure loss, thereby reducing the total aeration amount of the primary air 5. When it is determined in step 2 that the measured value of the total air flow rate of the primary air 5 is not larger than the target air flow rate as shown in FIG. 3 (b) to FIG. 3 (b). The on-off valve 27 on the branch lines 26a and 26e connected to the circumferentially divided flow paths 24a and 24e adjacent to both sides of the circumferentially divided flow paths 24b, 24c and 24d being vented, or FIG. As shown in FIG. 3 (b), the on-off valves 27 on the branch lines 26b and 26d connected to the circumferential divided flow paths 24b and 24d adjacent to both sides of the circumferential divided flow path 24c being vented are opened. Let me operate, the corresponding circumference Split passages 24a and 24e, or resumes the vent from 24b and 24d (Step 5: S5).

  In this way, the ventilation from the circumferential divided flow paths 24b, 24c, 24d, or the circumferential divided flow paths 24a and 24e adjacent to both sides of the 24c, or 24b and 24d is resumed. Since the width of the region in which the primary air 5 is blown from the furnace upstream side wind box 17a to the furnace upstream side portion serving as the drying zone 1a of the stoker furnace main body 1 is widened, the primary air 5 stays at the bottom of the furnace. The waste layer is also supplied to both sides in the width direction where the layer thickness is thinner. As a result, the pressure loss of the supplied primary air 5 is reduced, and the total ventilation amount of the primary air 5 is increased (step 6: S6).

  Therefore, after that, the process returns to Step 1 again to measure the total ventilation rate of the primary air 5, and then the total ventilation rate measurement value is compared with the target ventilation rate in Step 2 above, and according to the result. By repeating the procedure of Step 3 and Step 4 or Step 5 and Step 6, the entire furnace upstream side wind box 17a is ventilated within the range in which the target ventilation amount can be secured. The direction division flow paths 24a, 24b, 24c, 24d, 24e are limited to the center, and the region where the primary air 5 is blown into the upstream portion of the stoker furnace body 1 serving as the drying zone 1a is the width of the waste layer. It becomes concentrated in the center of the direction.

  As described above, according to the primary air supply device of the rotary stoker type incinerator of the present invention, the target ventilation rate is determined by the rated operation of the blower 25 for the layer of the waste 14 staying at the bottom of the stoker furnace body 1. Since the primary air 5 is blown in the central portion in the width direction where the layer thickness is thick, the time required for the blown primary air 5 to pass through the waste layer is within the range that can be secured. Is extended. Therefore, the primary air 5 blown into the waste layer becomes fully utilized for drying the waste 14 while it passes through the waste layer. In the zone 1a, the waste 14 is efficiently dried with a small amount of the primary air 5 as compared with the prior art.

  Therefore, the ventilation amount of the primary air 5 blown to dry the waste 14 from the furnace upstream wind box 17a to the drying zone 1a in the stoker furnace main body 1, that is, the ventilation amount of the primary air 5 in the drying zone 1a is set. , It can be reduced as compared with the prior art.

  Furthermore, by restricting the flow path to the center of the circumferentially divided flow paths 24a, 24b, 24c, 24d, and 24e of the furnace upstream wind box 17a, the sealing device 20 and the stoker furnace main body 1 side are limited. For example, it is difficult to perform a complete sealing action at the seal portion by the sealing fin 21 of the sealing fin 21, even from the circumferentially divided flow channel near the center to the circumferential divided flow channel adjacent to the outside thereof, that is, For example, as shown in FIG. 3B, when air is ventilated from the circumferentially divided flow paths 24b, 24c, and 24d, primary air 5 from the circumferential divided flow paths 24b to 24a or from 24d to 24e. When leakage occurs or only the circumferentially divided flow path 24c is ventilated as shown in FIG. 3 (c), the circumferential divided flow path 24c to the circumferential divided flow paths 24b and 24d on both sides thereof. of Even leakage following air 5 has occurred, it is possible to suppress a possibility reaching cover casing 8 side, by this, it is possible to suppress than the passing exhaust amount of primary air 5 in the prior art.

  For this reason, the amount of exhaust gas can be reduced, and the exhaust gas treatment device can be downsized. Moreover, the decrease in the amount of exhaust air of the primary air 5 can suppress the occurrence of a decrease in exhaust gas temperature that leads to the generation of dioxins and the occurrence of clinker due to early ignition at both ends in the width direction of the waste layer. Furthermore, since the drying efficiency of the waste 14 in the drying zone 1a can be improved, the furnace length of the stoker furnace body 1 can be shortened, and it is expected to contribute to the downsizing of the entire plant. it can.

  The present invention is not limited only to the above-described embodiment, and the furnace upstream side wind box 17a in the wind box 16 is divided into five circumferentially divided flow paths 24a divided into five in the circumferential direction of the stoker furnace body 1. Although shown as having 24b, 24c, 24d, 24e, as long as it is divided into four or more in the circumferential direction of the stalker furnace body 1 and until every interval of each water pipe 4 constituting the stalker furnace body 1, An arbitrary number of divisions may be set in the circumferential direction of the stalker furnace body 1.

  The control for causing the control device 30 to start or stop the aeration in order from the outer side in the width direction with respect to the circumferentially divided flow paths 24a, 24b, 24c, 24d, 24e of the furnace upstream side wind box 17a Waste 14 is dried in the upstream portion of the furnace where the total ventilation amount of the primary air 5 to the furnace upstream wind box 17a detected by the upper flow meter 28 becomes the drying zone 1a of the stoker furnace body 1. However, the pressure gauge 29 on the air supply line 26 is used to determine whether or not the target ventilation rate is larger than the required target ventilation rate. The pressure of the supplied primary air 5 is detected, and each of the above described pressures falls within a range that does not exceed the capacity of the blower 25 (a pressure range in which a desired total air flow rate of the primary air 5 can be obtained). Circumferentially divided flow path 4a, 24b, 24c, 24d, the start of the air flow to 24e, may be controlled to stop.

  A flow rate adjustment valve for adjusting the primary air amount 5 supplied to the entire furnace upstream wind box 17a is provided at a required position of the air supply line 26, and upstream of the flow rate adjustment valve in the air supply line 26. An air supply line with a flow control valve for supplying the primary air 5 to the furnace intermediate wind box 17b and the furnace downstream wind box 17c is branched and provided at the side position. You may make it supply the primary air 5 to each wind box 17a, 17b, 17c of the longitudinal direction of the box 16. FIG. Of course, various changes can be made without departing from the scope of the present invention.

1 shows an embodiment of a primary air supply device of a rotary stoker incinerator according to the present invention, and is a schematic cut front view of a furnace upstream side air box. It is a figure which shows the control flow of the control apparatus in the apparatus of FIG. 1 shows the operation state of primary air ventilation and ventilation stop of each circumferentially divided flow path in the furnace upstream wind box by the apparatus of FIG. 1, where (a) is vented from all circumferential divided flow paths (B) is the state where the ventilation from the circumferentially divided flow passages on both sides is stopped and the ventilation is performed from the portion closer to the center in the furnace upstream wind box, (c) is the circumferential direction of the center It is a figure corresponding to FIG. 1 which each shows the state which is ventilating only from a division | segmentation flow path. The outline of the rotary stoker-type incinerator is shown. (A) is a cut side view, (B) is an enlarged view taken along arrow A-A in (A), and (C) is an enlarged view of part B in (B). It is.

Explanation of symbols

1 Stoker furnace body 5 Primary air 14 Waste (processed object)
17a Furnace upstream wind box (wind box)
24a, 24b, 24c, 24d, 24e Circumferentially divided flow paths (venting regions)
25 Blower 26 Air supply line 26a, 26b, 26c, 26d, 26e Branch line (air supply line)
27 On-off valve 28 Flow meter 29 Pressure gauge 30 Control device

Claims (3)

While the workpiece to be treated supplied from the upstream side to the stalker furnace body placed horizontally is transferred to the downstream side while being agitated by the rotation of the stalker furnace body, it is dried by the primary air supplied from the wind box. In the rotary stoker type incinerator that is designed to be incinerated through the process of pyrolysis and combustion, a large number of ventilation areas are created by subdividing the wind box that supplies primary air to the upstream side of the furnace in the circumferential direction of the stoker furnace body. shall have, in the air feed line to direct the primary air from and blower respective venting regions said sub differentiation, the on-off valve is provided for each vent region, it is supplied to the windbox of the furnace upstream When it is determined that the total primary air flow rate is greater than the target air flow rate set in advance to dry the workpiece in the upstream part of the furnace, which is the drying zone of the stoker furnace body Or upstream of the furnace Pressure of the primary air supplied to the wind boxes, that is lower than the pressure of the primary air required for obtaining the target amount of aeration and close the opening and closing valve per each vent region in the circumferential direction suited et order A primary air supply device for a rotary stoker-type incinerator having a configuration capable of performing the above. While the workpiece to be treated supplied from the upstream side to the stalker furnace body placed horizontally is transferred to the downstream side while being agitated by the rotation of the stalker furnace body, it is dried by the primary air supplied from the wind box. The air box that supplies primary air to the upstream side of a rotary stoker incinerator that is designed to be incinerated through the process of pyrolysis and combustion is subdivided into four or more ventilation areas in the circumferential direction of the stoker furnace body. And an air supply line that guides primary air from the blower to each of the subdivided ventilation regions is provided with an open / close valve for each of the ventilation regions, and supplied to the wind box on the upstream side of the furnace. When it is determined that the total ventilation rate of the primary air is larger than the target ventilation rate that is set in advance to dry the workpiece in the furnace upstream portion that becomes the drying zone of the stoker furnace, Or the wind box on the upstream side of the furnace A configuration in which the on-off valve for each ventilation region can be closed in order from the circumferential direction when the pressure of the supplied primary air is lower than the pressure of the primary air necessary to obtain the target ventilation rate. A primary air supply device for a rotary stoker-type incinerator. It provided a circumferential flow meter for detecting the total ventilation amount of primary air supplied to each vent region or a pressure gauge for detecting the pressure of the primary air in the air feed line, based on the signal input flow meter or al Determine whether or not the total ventilation volume is greater than the target ventilation volume, or based on the signal input from the pressure gauge, the pressure gauge measurement value and the target ventilation volume The primary air supply device of the rotary stoker type incinerator according to claim 1 or 2, further comprising a control device that compares with the control device and gives an open / close command to the open / close valve for each ventilation region.

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