Abstract:
To provide a method of handling DPF capable of ensuring an expected value of a catching function of reclaimed DPF and eliminating waste of useful metals included by DPF, DPF( 1 ) mounted to a diesel engine for catching PM included in exhaust is reclaimed until being brought into a nonreusable state and remounted to the engine by at least once and in remounting, the DPF( 1 ) is mounted such that the DPF( 1 ) is mounted in the direction reverse to a direction of mounting at a preceding time.

Description:
BACKGROUND OF THE INVENTION  
         [0001]    1. Field of the Invention  
           [0002]    The present invention relates to a method of handling a diesel particulate filter.  
           [0003]    2. Description of the Related Art  
           [0004]    Exhaust gas (hereinafter, simply referred to as “exhaust”) of a diesel engine includes a large amount of granular matters when an air cleaner is clogged and when the engine is in rapid acceleration. The granular matters are constituted by C (free carbon by incomplete combustion, so-to-speak black smoke or soot) and SOF (Soluble Organic Fraction: uncombusted portion of diesel fuel and lubricant) both of which are pollution causing matters. Hence, there is an engine mounted with a filter for removing diesel particulate at an exhaust pipe of the engine for removing the granular matters from exhaust. Further, the granular matters are so-to-speak PM (Particulate Matters: hereinafter, simply referred to as “PM”). Further, the filter for removing diesel particulate is so-to-speak DPF (diesel particulate filter: hereafter, simply referred to as “DPF”).  
           [0005]    Here, residuary substances produced by combustion of caught PM are deposited on a PM catching face of DPF and therefore, the catching function of DPF is deteriorated. Hence, deteriorated DPF is removed from the engine and washed and remounted to the engine or interchanged by a new article. Unnecessary DPF is scrapped.  
           [0006]    Meanwhile, a direction of mounting DPF to the engine is normally determined as can be exemplified in other filters such as a fuel filter, a lubricant filter, a working fluid filter and an air cleaner. Further, DPF is not a simple filter and catcher but includes various kinds of useful noble metals for constituting oxidation catalysts. Therefore, there are the following drawbacks.  
           [0007]    (1) A flow rate of exhaust stays the same before and after DPF and therefore, it is preferable to constitute DPF to be able to use revertedly. In this case, even when a reversing type DPF is reclaimed (washed as mentioned above) until DPF cannot be used again and remounted to the engine, the remounting is carried out manually. Therefore, in remounting, the DPF may be mounted in a direction the same as that in mounting the DPF at preceding time by mistake or ignorance. Further, when such an erroneous operation is repeated, the remounted DPF cannot achieve an expected value of the catching function (service life). Further, a time period of making the DPF unreusable is shortened. That is, useful metals are wasted and the effect of using the DPF is halved.  
           [0008]    (2) When the DPF is scrapped by interchanging the DPF by a new article although the DPF can be washed and remounted, limited resources are wasted.  
           [0009]    (3) It is desired to recover DPF to be scrapped efficiently to thereby recover and reuse useful metals.  
         SUMMARY OF THE INVENTION  
         [0010]    In view of the above-described drawbacks and future perspective, it is an object of the invention to provide a method of handling DPF (Diesel particulate Filter) capable of resolving at least one thereof.  
           [0011]    In order to achieve the above-described object, according to an aspect of the invention, there is provided a method of handling a diesel particulate filter wherein the diesel particulate filter mounted to a diesel engine for catching particulate matters included in an exhaust gas is reclaimed until being brought into a nonreusable state and remounted to the engine at least by one time, and in mounting the filter, the filter is mounted such that the filter is mounted in a direction reverse to a direction of mounting the filter at a preceding time.  
           [0012]    Further, in remounting DPF, it is preferable to provide a mark indicating a direction of mounting in remounting the filter at a current time to DPF.  
           [0013]    Further, it is recommendable that it is determined that the filter is nonreusable by a predetermined number of remounting the same DPF or at least one of predetermined fluid pass resistance and fluid pass flow rate of DPF.  
           [0014]    According to the above-described constitution, DPF is mounted revertedly in the direction reverse to the mounting direction at the preceding time at each time of remounting DPF and therefore, an expected value (service life) of a catching function of remounted DPF can be ensured. Further, a time period reaching a nonreusable state of the filter is prolonged. That is, useful metals are not wasted and the effect of using DPF can maximally be achieved. Since the determination of nonreusableness is made clear, DPF to be scrapped can efficiently be recovered and useful metals can be recovered and reused. 
       
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0015]    [0015]FIG. 1 is a flowchart showing an embodiment according to the invention;  
         [0016]    [0016]FIG. 2 is a partially sectional perspective view of DPF according to the embodiment;  
         [0017]    [0017]FIG. 3 is a schematic view viewed from Z direction of FIG. 2;  
         [0018]    [0018]FIG. 4 is a schematic view viewed from X direction of FIG. 2;  
         [0019]    [0019]FIG. 5 is a front view of a plate inserting member provided at an observable face and a plate inserted into the member insertably and drawably according to other embodiment;  
         [0020]    [0020]FIG. 6 is a sectional view taken along a line P 3 -P 3  of FIG. 5;  
         [0021]    [0021]FIG. 7 is a plane view of the plate of FIG. 5; and  
         [0022]    [0022]FIG. 8 is a schematic view of a test apparatus of washed DPF. 
     
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS  
       [0023]    Embodiments according to the invention will be explained in reference to FIG. 1 through FIG. 8. First, DPF 1  used in the embodiments will be explained in reference to FIG. 2 through FIG. 5. Further, FIG. 2 is a partially sectional perspective view of DPF 1 , FIG. 3 is a schematic view viewed in Z direction of FIG. 2 and FIG. 3 is a schematic view viewed in X direction of FIG. 2.  
         [0024]    As exemplified in FIG. 3, DPF 1  of FIG. 2 is arranged with holes  1   a  and closures  1   b  alternately and contiguously and formed in checkers as a whole. Further, according to DPF 1 , as shown by FIG. 4, the holes  1   a  at one face and the closures  1   b  at other face are arranged at corresponding positions of DPF 1  in the left and right direction. Further, porous partition walls  1   c  are sandwiched between edges opposed to each other in edges of the closures  1   b . The porous partition wall  1   c  carries an oxidation catalyst. Further, as shown by FIG. 2, a flange portion  1   d  is provided at an outer periphery of a central portion between left and right faces of DPF 1  and can be fastened to an exhaust pipe of a diesel engine, not illustrated, by bolts via a plurality of bolt insertion holes  1   e  provided at the flange portion  1   d . That is, DPF 1  is of a reversing type mountable to the engine reversibly.  
         [0025]    According to DPF 1 , as exemplified in FIG. 4, exhaust from the left face as illustrated permeates the porous partition wall  1   c  and is exhausted from the right face as illustrated. Further, when the exhaust permeates the porous partition wall  1   c , PM in exhaust is oxidized (that is, combusted) by the oxidation catalyst to be cleaned thereby.  
         [0026]    Here, in order to efficiently recover and reuse useful metals included in DPF 1 , it is preferable to concentratedly carry DPF 1  having deteriorated PM catching function into a reclaiming plant, reclaim a reusable one thereof, meanwhile, recover and reuse useful metals by disintegrating a nonreusable one thereof. Hence, according to the embodiment, DPF 1  is handled as shown by FIG. 1.  
         [0027]    A plurality of service bases C are allocated to one reclaiming plant B. A number of diesel engines are operated in a service territory (field A) of the service base C. Hence, a “contract concerning handling of DPF” is exchanged among the reclaiming plant B, the service base C and engine owners. Thereby, a service engineer in service from the service base C removes DPF 1  having a deteriorated PM catching function from the engine of the engine owners in the field A (step  1 ). At this occasion (or after steps  3  and  4 , mentioned later), the service engineer confirms a mark indicating a number of times of mounting n until the occasion of DPF 1  provided to the removed DPF 1  (step  2 A). Further, DPF 1  carried to interchange is mounted to the engine (step  3 ). Further, although the carried DPF 1  is either of a new article and a reclaimed article, in either of them, the carried DPF 1  is provided with a mark indicating what number of times of mounting number n mounting at a current time corresponds to for the DPF 1  (step  4 ). Specifically, when the new product is marked as “n=1”, the recycled article is marked as “n=n+1”. Meanwhile, the mark n signifies a mounting direction as described later in details in reference to FIG. 2, mentioned above. Hence, in step  3 , when the carried DPF 1  is a reclaimed article, the reclaimed article is provided with mark n based on step  4  in mounting at a preceding time and accordingly, the mounting direction in mounting at the preceding time of the reclaimed article can be read from the mark n. Hence, in mounting at the current time, DPF 1  can be mounted to the engine in a direction reverse to the mounting direction at the preceding time and mounted in this way (step S 32 ).  
         [0028]    After finishing to interchange DPF 1 , the service engineer records an engine number, owner&#39;s name, mark n of removed DPF 1 , an operation date, engine operation accumulated time (accumulated running distance in the case of a running vehicle) and so on and sends removed DPF 1  to the reclaiming plate B along with a copy of the record.  
         [0029]    The reclaiming plant B firstly confirms mark n of DPF 1  in order to determine whether a number of DPF 1  sent from the respective service base C indicates a reusable state (step  2 B). Here, mark n indicates mounting number n until removing DPF 1 . Hence, the reclaiming plant B compares a limit remounting number no previously determined for this kind of DPF 1  with mark n (step  5 ). Further, according to the embodiment, “no=4”. Here, “n=0” indicates that DPF 1  is an unmounted new article  3 , “n=1” indicates a mounted new article and “n=2 through 4” indicates a remounting number n of times of a reclaimed product. Hence, when “n=4” (n=no) in step  5  of executing the comparing determination at the reclaiming plant B, DPF 1  is disintegrated and useful matters are recovered (step  6 ) and reused (step  7 ). Meanwhile, when “n=1 through 3” (n≠0 and n&lt;no), DPF 1  is washed and reclaimed (step  8 ). Further, it is tested whether reclaiming is carried out excellently (step  9 ). When the test result is excellent, the DPF  1  is transported to the service base C and stocked at the service base C (step  10 ). Further, the service base C constituting a destination of transportation needs not to be a source of transportation of the DPF  1 . Although there is also a case of constituting “a destination of transportation=a source of transportation” by a contract, the case requires extra time and labor and is disadvantageous in providing inexpensive service. Meanwhile, when the test result is a failure (that is, nonreusable), the test result is reported to the service base C constituting the source of transportation of the DPF 1  (steps  11 ) and the above-described steps  6  and  7  are applied to the DPF 1 .  
         [0030]    As described in step  10 , the service base C stocks the reclaimed article  1  transported from the reclaiming plant B as well as the new article  1  at a stock yard (step  10 ). Further, when a predetermined time (predetermined time period, predetermined number of days) has elapsed since interchanging DPF 1  at a preceding time (step  12 ), the service base C coordinates with the engine owner with regard to in-service time to field A for interchanging DPF in consideration of the contract, the record until the preceding time and the report from the reclaiming plant B (step  13 ). Based on the result of coordination, the service engineer selects either one of a reclaimed article and a new article (step  14 ), gets in service to field A by carrying the either one (step  15 ) and interchanges DPF based on steps  1  through  4 , mentioned above. Further, the above-described step  2 A may be omitted.  
         [0031]    Meanwhile, a specific example of “the mark n constituting the mounting number n signifies the mounting direction”, will be explained in reference to FIG. 2.  
         [0032]    As mentioned above, DPF 1  is of the reversing type. Further, as shown by FIG. 2, the flange portion  1 D is previously illustrated with numbers  1  through  4  and O marks right therebelow. Hence, when the service engineer mounts the carried DPF 1 , the service engineer strikes a recessed mark by using a punch or the like at the DPF 1  in an order of the numbers  1  through  4  at inside of a O mark which is not present from the start. There is made a rule “when DPF 1  immediately before being mounted, is provided with the recessed marks up to an odd number ( 1  or  3 ) thereof, the DPF 1  is mounted by constituting a number describing face thereof as an exhaust side (side of viewing FIG. 2 in Z direction). Further, there is also made a rule “when DPF 1  immediately before being mounted is provided with the recessed mark at even number  2  thereof and there is not the recessed mark, the DPF 1  is mounted by constituting the number describing face as an intake side (side of FIG. 2 opposed to Z direction)”. The above-described rules constitute an operation standard of the service engineer. That is, “the mark n constituting the mounting number n signifies the mounting direction”.  
         [0033]    Specifically, DPF 1  carried for interchanging at steps  3  and  4  is marked with “n=0 through 3”. Here, when “n=0, the DPF 1  is a new article. In this case, DPF 1  is mounted by constituting the number describing face as the intake side and O mark of number  1  is punched. Further, when “n=1” or “n=3”, the DPF 1  is a reclaimed article reclaimed by one time or three times. In this case, DPF 1  is provided with one punch mark (recessed mark at number  1 ) or three thereof (recessed marks respectively at numbers  1  through  3 ). That is, the mounting direction of DPF 1  at a preceding time shows that the number describing face has been disposed on the intake side. Hence, in the mounting direction at current time, DPF 1  is mounted by disposing the number describing face on the exhaust side and O mark of number  2  or  4  is newly punched. Further, when “n=2”, DPF 1  is a reclaimed article reclaimed by two times. In this case, DPF 1  is provided with two punch marks (recessed marks at numbers  1  and  2 ). That is, the mounting direction of DPF 1  at the preceding time shows that the number describing face has been disposed on the exhaust side. Hence, in the mounting direction at the current time, DPF 1  is mounted by disposing the number describing face on the intake side and O mark of number  3  is newly punched.  
         [0034]    An effect of the embodiment will be described.  
         [0035]    (1) Since DPF 1  is revertedly mounted in a direction reverse to the mounting direction at the preceding time at each time of remounting, the expected value (service life) of the catching function of remounted DPF 1  can be ensured. Further, a time period reaching a nonreusable state is prolonged. That is, useful metals are not wasted and an effect of using DPF is maximally achieved.  
         [0036]    (2) Since three parties of the field (engine owner), the service base and the reclaiming plant are united with the service contract as a medium, optimum interchange, concentrated reclaim and concentrated reuse of DPF 1  can be achieved and the economic effects are superposed respectively for the three parties. Further, DPF which has been scrapped conventionally despite being reusable, can systematically be reclaimed and remounted by a number of times until the nonreusable state, limited resources can be recovered summarizingly from nonreusable DPF and therefore, there is no waste.  
         [0037]    Other embodiments will be exemplified and enumerated as follows.  
         [0038]    (1) Although according to the above-described embodiment, numbers  1  through  4  and O marks are provided at the flange portion  1   d  of DPF 1 , as also illustrated in FIG. 2, the numbers and the O marks may be provided on an outer peripheral face of DPF 1 . Operation and effect thereof are similar to those of the above-described embodiment.  
         [0039]    (2) Although according to the above-described embodiment, numbers  1  through  4  and O marks are provided at the flange portion  1   d  of DPF 1  and/or the outer peripheral face of DPF 1 , in this case, the numbers and the O marks may be able to confirm only when DPF 1  is somewhat removed. Although a hindrance is not constituted thereby, in order to confirm the numbers and the O marks in outlook thereof without removing DPF 1 , an observable external surface of an engine main body or a machine mounted to the engine maybe marked. FIG. 5 through FIG. 7 shows such as case. An observable external surface  2   a  is fixedly installed with a plate inserting member  4 . The plate inserting member  4  is of a frame structure having a window at its center. Meanwhile, a plate  5  made of aluminum provided with numbers  1  through  4  and O marks is prepared. The plate  5  is inserted insertably and drawably to and from the frame of the plate inserting member  4  and numbers  1  through  4  and O marks on the inserted plate  5  can be observed from the window. Further, at each time of interchanging DPF, a recessed mark the same as a recessed mark provided to DPF, is provided to O mark (punchably). After providing four recessed marks, the plate  5  is replaced by a new one.  
         [0040]    (3) Although according to the above-described embodiment, numbers  1  through  4  and O marks are provided, recessed marks may be provided by dispensing with these. Because a number of the recessed marks is the mounting number n and for each number, the mounting direction of the carried DPF 1  is signified. That is, numbers  1  through  4  and O marks can inherently be dispensed with. In the above-described embodiment, provision of numbers  1  through  4  and O marks is aimed at avoiding unnecessary erroneous recognition by standardizing marking portions. Further, it is not also necessary to limit the mark to the recessed mark but may be, for example, a painted mark. In sum, painted mark will do so far as the service engineer can grasp the number of times of interchanging, can confirm the mounting directions at the preceding time and/or the current time and can mark the mark.  
         [0041]    (4) Although according to the above-described embodiment, the mounting number “n=4” constitutes a reference of determining that DPF is nonreusable, the determination reference differs from a determination reference at the test of step  9  of FIG. 1. Specifically, according to the above-described embodiment, as shown by FIG. 8, the reference is constituted by predetermined fluid pass resistance at DPF 1 . That is, DPF 1  is put into a test box  6 , air pressure  7  is applied thereto and front and rear pressure difference Pp (=P 1 −P 2 ) of DPF 1  is measured. Further, when the front and rear pressure reference Pp is out of a value Po in a predetermined range, the DPF 1  is determined as nonreusable. Further, although not illustrated, the flow rate Qq of a flow flowing in DPF 1  by applying predetermined air pressure, may be measured by a flow rate meter. Also in this case, when the measured flow rate Qq is out of a value of Qo in a predetermined range, the DPF 1  is made nonreusable. This is also because DPF 1  has been washed and therefore, also in this case, it is shown that the PM catching function of the DPF 1  is deteriorated.