JPS6058133B2 - How to pay out raw materials - Google Patents

Description

[Detailed Description of the Invention] The present invention stores an extremely wide variety of raw materials in a part of a vast site, such as a steel mill, and further stores these raw materials in individual units installed at a wide variety of facilities. This invention relates to a raw material dispensing method for efficiently replenishing a storage tank without running out of stock.

At a steelworks, a wide variety of raw materials and sub-resources (e.g. iron ore, coke, limestone, etc.) are used in order to manufacture steel or carry out various production or processing operations associated therewith.
It requires raw material collection and distribution sites to store these materials.

In particular, in Japan, it is necessary to seek overseas for the above raw materials, etc. (hereinafter simply referred to as raw materials), and in a situation where raw material import sources are expanding to various parts of the world due to the depletion of resources, iron ore, etc. Even so, the quality and properties vary depending on the source of the material, and it must be used differently depending on the purpose and content of production or processing. In other words, it is necessary to separate and store such a wide variety of raw materials with different quality and properties (hereinafter referred to as raw materials by brand), which requires a larger raw material collection and distribution area. In the vast collection and distribution area, raw materials for each brand are piled up in piles, touching each other. By the way, the above-mentioned raw material collection and distribution area in a steelworks is generally called a storage yard (abbreviated as yard), but as mentioned above, it is necessary to store an extremely wide variety of raw materials by brand, and The raw materials stored in the yard are sent to various facilities for use. Cargo ships are being shipped out without any delay, with various selections being made, and moreover, cargo ships are arriving one after another. The various brands of raw materials and ingredients unloaded from the 2000-2000 (built adjacent to the 2000-2000) must be transported to designated storage locations and piled up in piles at the designated storage locations. Because of this background, ordinary yards are long and narrow, and multiple yards are installed in parallel, leaving enough width for the conveyance means, so that raw materials can be taken in and out conveniently and easily. There is a limit to the number of yards that can be used. On the other hand, since the number of brands far exceeds the number of yards, it is necessary to accumulate raw materials of multiple brands in one yard, and raw materials of different brands are distributed along the length of the yard. The above-mentioned situation occurs in which the shoes are accumulated in a mountain shape so that the heel touches the heel. This situation is well known; for example, in Japanese Patent Application Laid-Open No. 48-3686
A part of it is introduced in Waniya and No. 481-87571. By the way, the raw material collection and distribution area with such a configuration is equipped with transport equipment for discharging the stored raw materials.
These devices are connected to other conveyance devices for further conveying the stored raw materials to equipment that uses the raw materials, such as blast furnaces. Various types of conveyance equipment are known, but they can be broadly categorized into: reclaimer group RCl for scraping out stored raw materials from the pile position in each yard; ground belt conveyor arranged in the longitudinal direction of each yard; Group ■ ℃, system belt conveyor group ℃, which transports the raw materials discharged in this way to the vicinity of each used equipment group P; can be mentioned. Of course, in steel works and other facilities that use powder and granular materials, conveyance equipment other than the above may be used depending on the individual environment, and the above equipment may be called by other names, and each of the above equipment may also be used. In some cases, the class itself is not a single piece of equipment, but a combination of multiple and different types of unit equipment.
In the following, for convenience of explanation, raw material delivery in a steelworks will be discussed, and the reclaimer RCl ground belt conveyor YBCl system belt conveyor L° C. and tripper TR will be described as the main conveyance equipment. At a steelworks, the raw materials of many brands accumulated in the yard are evenly distributed and supplied to storage tanks B, which are distributed throughout almost the entire area of the plant.
The transport equipment mentioned above is spread out like a net between the yard and the storage tank, but they branch or merge along the way, and there are no branching points, merging points, or transfer points. become extremely numerous.

In other words, there are an extremely large number of possible transport routes between the raw material distribution area and the storage tank, considering it mathematically. However, focusing on the accumulation position of a specific brand of raw material in a certain yard and a specific storage tank B for using the raw material for a specific purpose, a combination of specific equipment selected from the above-mentioned transport equipment is installed between them. Considering the case where they are connected (hereinafter, this kind of connection is referred to as serialization of conveyance routes),
Some of the transport equipment that can be directly or indirectly connected to the route may become unusable because the route before or after it becomes a kind of reserved state. Therefore, at the stage of arranging transport routes for other storage tanks, the selectable range of transport equipment becomes narrower. In this way, the number of usable conveyance devices decreases as the conveyance routes are sequentially organized into the third, fourth, and so on. That is, the number of conveyance routes that can be grouped from the reclaimer RC to the tripper TR is limited. In other words, the total number of storage tanks in a steelworks is usually smaller than the number of transport routes that can be grouped. However, on the other hand, the equipment at the steelworks continues to operate day and night, and the raw materials in each storage tank are constantly decreasing, so it is necessary to continue replenishing each storage tank with raw materials. Optimal planning is required for the payout operation. Despite the need to create optimal plans in this way, conventional plans have been made manually by experienced operators, resulting in various problems as described below. Ta.

To roughly explain the conventional planning procedure, the planner first pays attention only to preventing accidents such as tank outages during the time he or she is responsible for (for example, 8 hours). After detecting a storage tank that is considered to be the closest to running out, the storage tank and any corresponding transport route are organized into a series.

Of course, even at the time of planning this first stage, raw materials have been continuously being discharged from the time before that, so all or part of the conveyance equipment that we would like to use for the above-mentioned series has already been used as described above. There may be cases where the reservation status is as shown below. In such a case, you have to wait until all the reservations for the transport equipment you want to use for grouping are cancelled, but the storage tank originally selected here is one that is close to running out of tanks, as mentioned above. Since there is a lot of water, there is no reason to keep it waiting for too long, and as I will explain later, the tank is in danger of running out. If, fortunately, the serialization is completed without causing the first storage tank to run out, then next time we will select the next storage tank that is likely to run out and change the corresponding transport route in the same way. It will be serialized into.

However, in each of the second, third, etc. storage tanks, all or part of the transport equipment that you want to use for grouping may be reserved, so you can freely select the transport equipment and group it at any time. There's no way it can be changed. In this way, the traditional planning method
It is just a chronological time schedule method that moves forward one step at a time in response to the passing of time.
Anticipating the future state after a certain period of time, and working towards it,
Or rather, it was not a planning method in which a plan was drawn up from the future state to bring it closer to the present, but rather it was more of an ad hoc plan that only needed to be able to deal with the immediate situation.

Therefore, we frequently encounter the above-mentioned reservation situation and get stuck, and are forced into a situation where we are forced to take emergency measures such as revising the plan or adopting piecemeal transportation, and the planning process itself is interrupted. Problems arose, such as the long time it took to carry out the process, and the rising cost of power due to the transportation of small pieces, and in some cases even causing serious accidents such as the tank running out. If this were to happen, there would be no choice but to use truck transportation or emergency grouping that ignored the plan, which would throw off all plans and cause the problem of running out of tanks spreading to other storage tanks as well. Furthermore, the conventional planning method completely lacks the perspective of trying to maximize the total amount transported from the yard to all storage tanks, so the efficiency of transporting raw materials for the entire operation of the factory etc. is poor, and the storage tank As a result, the storage rate relative to the total storage capacity of the tank had to be lowered, and the number of occurrences of near-out of tanks increased, making it difficult to maintain leeway in the overall plan, which led to the aforementioned inconveniences. be. In recent years, various control methods have been proposed and implemented in order to improve the above-mentioned drawbacks (Japanese Patent Application Laid-open No. 48-87571 and No. 48-3686).
9 is one example), but in both cases, the emphasis is on arranging each transport route into series, and the current situation is that they have not reached the point of optimizing the transport capacity. The present invention was made in consideration of such a situation, and the necessity of raw material replenishment is determined by arranging each conveyance route in series while taking into consideration the storage status in the storage tank and the status of the conveyance equipment currently in operation. The objective is to set a method that gives priority to the following items, and also increases the operating status of transport equipment to the highest level and maximizes the total amount of raw material discharged.

To give an overview of the method of the present invention that has achieved the above object, it detects the amount of ore in each storage tank at regular intervals, learns the storage tank that needs to be discharged, and prioritizes the system according to the needs of the discharge. After determining the necessary dispensing transport route (i.e., route transport machine), the transport plan is determined so that the transport amount on all routes is maximized, taking into account the continuous dispensing from the previous cycle. The purpose of this system is to transport the target brand of raw material from the raw material collection and distribution area to the storage tank based on this determination result. (a) The current amount of raw materials in stock for each storage tank. (b) Detect the raw material consumption amount BTONH per unit time for each storage tank; (c) The raw material inventory amount V
From the raw material consumption amount BTONH, calculate the time t until the inventory level decreases to the set inventory level Vmin for each storage tank, and calculate (d
) Determine the priority order for dispensing raw materials to each storage tank in order of the shortest holding time (t), and (e) decide the raw material brands that need to be replenished for each storage tank in order from the storage tank with the highest dispensing priority. (f) In the selection, the equipment can be used after (112) or less of the sampling period has elapsed. (g) By the selection, the raw material conveying route from the specific brand existing part of the raw material distribution area to each storage tank is specified, and the new dispensing series is completed. (h) Storage tanks in which dispensing was performed during the previous sampling cycle using the raw material transport route of the new dispensing series are subject to continuous dispensing, and (
1) Transport operating time X during the current sampling cycle for new dispensing work using the raw material transport route of the new dispensing series, and continuous operating time Y during the current sampling cycle for continuous dispensing work using the raw material transport route related to the continuous dispensing.
The storage amount in each storage tank is the maximum allowable storage amount Vmax
Under the condition that the following is maintained, the total transport amount in all raw material transport routes is determined simultaneously to be the maximum, and (j
) Based on the above-mentioned two transport operation times be.

FIG. 1 shows the arrangement of various transport devices that are the target group for grouping in this method. On the drawing, various brands of ore stored in each storage yard Y are usually collected by a reclaimer RC within its coverage area, and a ground belt conveyor YBC corresponding to the reclaimer and a system belt conveyor corresponding to the ground belt conveyor ■ °C and reach each storage tank B (hereinafter sometimes referred to as an ore storage tank) via trippers TR corresponding to the system belt conveyor. However, each response of the above-mentioned route conveyance engine is ignored in the event of a failure or the like. Serialization is performed by detecting the storage tank with a withdrawal request, determining the brands (plurality) that require withdrawal, and determining the location of the storage yard to be discharged.When the seriesization is completed, the yard Y1 reclaimer The RCl belt conveyor ■°C, the system belt conveyor TBCl tripper TR, and the ore storage tank B are connected in series, and a series conveyance route is determined. Now, the outline of the method for discharging ore according to the present invention will be explained below in order of steps. (1) Setting the sampling period First, in the present invention, the period of the payout plan to each ore storage tank is set to a sampling period of an appropriate length, taking into account the ease and rationality when arranging the series in response to the request for payout. divided into
An optimal plan is drawn up for each cycle.

This sampling period is determined based on the fact that two payout operations can be performed during the period. This is because, as will be described later, the payout in one sampling period of the present invention covers both the new payout requested in that period and the continued payout from the previous sampling period. (■) Detection of inventory and usage status of ore storage tanks Next, for each set sampling period, the inventory amount V and the consumption status of all ore storage tanks (the amount of consumption per unit time BTONH)
).

It is preferable to know this through actual measurement, but it may also be estimated from the actual measured value and payout plan in a previous sampling period close to that period. (■) Calculating the holding time of the ore storage tank Based on the above results, the holding time t of each tank, that is, the necessary time until the stock level decreases to the set stock level Vmin is calculated.

The set inventory level Vmln is the minimum level determined for each ore storage tank depending on the brand of raw material stored and the capacity of the ore storage tank, and if it falls below this level, raw materials will run out or a certain quality will be lost. It becomes impossible to stably supply raw materials to the raw material usage process. (■) Determining priority order of payout Based on the holding time t of each ore storage tank, determine the priority order of new ore storage tanks to be paid out within the current sampling period.

In this case, the holding time t for each ore storage tank to reach the set stock level ■Min is determined in descending order of the number of holding times t, but if there is an ore storage tank that is below the above level, the holding time t is displayed as a negative value. This will immediately affect the raw material usage process. Therefore, the ore storage tank should be given top priority. (■) Serialization of conveyance routes Once the priority order for dispensing is determined, various conveyance devices installed between the raw material yard and the ore storage tank are selected and sequenced in that order.

In this case, devices that are currently available (at the start of the cycle) are of course subject to selection, but even if they are not currently available, devices that become usable and available within 112 hours of the sampling cycle are also considered usable. and will be subject to series.
In other words, when the sampling period reaches 6 gin, even if the device to be grouped is currently in use, it may be grouped if the unusable state is lifted within three cycles. In other words, when creating a series using only equipment that is free from the beginning, as in the past, payout cannot be performed until all the necessary equipment is available, and during that time the equipment is idle and the operating rate is poor. However, in the present invention, the equipment is grouped including the equipment being used, and the start time of a new payout and the stop time of payout on a route that already includes the equipment (that is, continuing from the previous sampling cycle). The device is designed to eliminate play in the equipment by adjusting the stop timing of the dispensed items and making them continuous. However, if devices that are scheduled to be used beyond the period of 112 are also grouped, it is not preferable because although there is little play in the devices, it will not be possible to respond to requests for payout. (■) Determination of dispensing time Dispensing will be carried out for the ore storage tanks for which serialization has been completed, but in this method, in addition to this new dispensing, the continuation of the dispensing for the ore storage tanks that were disbursed in the previous sampling cycle. Payments will also be made.

The ore storage tank targeted for continuous dispensing is the one that was previously disbursed on the transport route that includes the equipment used in the series transport route for new dispensing. Therefore, the conveyance time X1 for the new dispensing and the conveyance time Y1 for the continuous dispensing are determined so that the total conveyance amount of ore on each series conveyance route in the period is maximized. Moreover, at this time, the determination is made under the condition that the storage amount in each ore storage tank is maintained below the allowable maximum storage amount ■Max. Of course, sufficient consideration should be given to the operating status of the various devices used for both payouts so that they are not idle within the cycle and are not used redundantly at the same time. A specific method for determining the above-mentioned transport times is performed by applying a well-known linear programming method described later to solve an objective function that maximizes the total transport amount. When the transport time is determined in this way, the payout plan for that cycle is completed. Based on this, new and continuing payout operations are executed. Next, the details of the serialization will be explained based on the computer flowchart shown in Fig. 2.First, the inventory amount V of each ore storage tank is detected, and the amount of consumption BTONH of each ore storage tank is detected.
is detected, and the retention time t of the ore storage tank is calculated. The retention time t is compared for each ore storage tank, and the payout priority is set in descending order of retention time t. Starting from the highest priority ore storage tank, the brand corresponding to the ore storage tank is known from a table stored in the computer, and the yard address corresponding to the brand is determined from the table stored in the computer. At this time, information corresponding to already paid out ore storage tanks is omitted. Next, the amount of yard inventory is read from the yard map stored in the computer and compared with the amount of ore to be discharged, and the yard to be discharged is determined so that the amount of yard inventory is not less than the amount to be discharged. decide. Once the yard address is determined, it is investigated whether the reclaimer guarding the address where the brand is located is out of order or in operation, and if the failure time or usage time is 11'2!1F. If it is full, it is not considered to be out of order or in use, and is included in the series. At the same time, the reclaimer's cross (located in the direction opposite to the work position with respect to the predetermined yard) is checked, and if it is crossed, the work of replacing the reclaimer is automatically performed within the computer. Once the reclaimer number is determined, the ground belt conveyor number corresponding to that reclaimer is determined. However, the measures to be taken during failure or during operation are the same as those for reclaimers. Once the number of the ground belt conveyor is determined, the corresponding system belt conveyor number is determined. However, the measures to be taken during failure or during operation are the same as those for reclaimers. Once the system belt conveyor is determined, the corresponding tripper number is determined. However, the countermeasures against failure or during operation are the same as in the case of a reclaimer. On the other hand, the conveyance time required for new dispensing and continuous dispensing according to the present invention is specifically determined by maximizing Q (total conveyance amount), which is formulated as follows, under the constraint conditions.

However, Xi+Y1≦T (1=1~n)
(2) However, X1 is the conveyance time for a new payout on the i-th series conveyance route in the sampling period, and Yi is the continuous payout on the i-th series conveyance route in which payout continues from the previous sampling cycle within the relevant sampling cycle. transport time, Al, is the transport capacity when ore is transported to the j ore storage tank via the i-th series transport route, and Aik is the transport capacity when the ore is transported to the k ore storage tank via the i-th series transport route. , ■Kmax, Vjmax is the maximum allowable storage amount of each K,j ore storage tank, Vk, Vi is the inventory amount of each K,j ore storage tank, BT
ONHk and BTONHj are the amount of digestion (cutting amount) per unit time of each K, j ore storage tank. (1) to (4) above
) When Xi and Yi are optimized using the formula, the payout series, payout time allocation, and payout amount are output.

Next, the raw material dispensing method according to the present invention will be explained in more detail based on a specific example.

Figures 3A, B to 5 are storage yards 1YR to 5Y.
Various raw materials 1 to 18 are stored in the reclaimer 1
RC~5RC1 Ground belt conveyor 1YBC~5YBC
For example, 4 systems of conveyors consisting of system belt conveyor 1TBC to 4TBC, 1 tripper 1TR to 4TR are installed, and 18 ore storage tanks are installed, 6 each for each plant 1P to 3P, 1B to 6B each. shows.

Note that the Arabic numerals in Figures 3 and 6 indicate raw material brands.

It is assumed that the series conveyance machine operating at the start of the sampling period T (6 samples in this case) is in the state shown by the bold solid line in FIG. 3A and the mark in FIG. 4.

Now, considering the conveyance path of the system belt conveyor η℃ as a series of conveyors, as shown in Fig. 3A, the first series 1TBC has 3RC at the start of the sampling period.
, 3YBC, feeds out raw material No. 9 (indicated by a roughly horizontal hunting line) from 4YR, passes through 2TR to 5B of 2P.
Raw materials are being transported to the ore storage tank (indicated by the approximately horizontal hunting line). The conveyance time of continuous payout that is included in the sampling cycle of this conveyance route from the previous cycle is Y1
(See Figure 4). Similarly, the second series 2TBC is 1R
Connected to C11YBC and raw material 1 from storage yard 1YR
The material is delivered to the 1B ore storage tank of 1P (indicated by the lower left rehatching line) through 1TR, and the transportation time for continuous delivery is Y
2 (see Figure 4). 4th series 4TBC is 5RC1
It is connected to 5YBC and discharges raw material No. 13 (indicated by the approximately vertical hunting line) from the storage yard 5YR, and transports the raw material to the 1B ore storage tank (indicated by the approximately vertical hunting line) at 3P via 3TR. The conveyance time for continuous payout is Y4 (see FIG. 4).

Assuming that the transport times Y1 to Y4 of each continuous payout satisfy the condition T/2 or less, each series is used for the next transport after each time period has elapsed.

Now, it is assumed that within the sampling period, requests for raw material dispensing (new dispensing) are made to raw materials No. 5, 8, and 16. In this case, as shown in FIG.
Refer to the thick solid line in FIG. 3B], and the third line does not discharge the raw material. That is, the first series 1TB
C is connected to 2RC and 2■℃ to discharge raw material No. 8 (indicated by the lower left rehatching line) from storage yard 2YR, and passes through 2TR to 2P's 3B ore storage tank (indicated by the lower left rehatching line). Transports raw materials. At this time, the time used for dispensing raw material No. 8 within the sampling period is X1 (see FIG. 4). Similarly, the second line 2TBC is connected to 3RC and 3YBC and discharges raw material No. 5 (indicated by a substantially horizontal hunting line) from 3YR.
The raw material is transported to the 4B ore storage tank of 1P (indicated by a substantially horizontal hunting line) via 1TR, and the transport time is X2 (see Fig. 4). As mentioned above, the third line does not dispense raw materials. The 4th train 4TBC is connected to 5RC and 5YBC and discharges raw material No. 16 (indicated by the rehatching line on the lower right) from the storage yard 5YR, and passes through 4TR to 3P's 2B.
The raw material is transported to the ore storage tank (indicated by the rehatching line on the lower right), and the transport time is X4. (See Figure 4). When dispensing to the target ore storage tank using the conveyance system organized as described above, the total dispensing amount delivered in a certain sampling period is maximized.

This can be expressed as a formula as follows. 1TBC, 2T
About R: About 2TBC, 1TR: About 3TBC, 4RC, 4YBC, 4TR: 4TB
Regarding C, 5RC, 5YBC: Regarding 3RC, 3YBC: Regarding 4TR: Plant No. l, Pin No. About l: Plant N
O. 3. Pin No. About 3: \1U Noplant NO.
．． 3. Pin No. About l: Plant No. 2. Pin No. Regarding 3: Plant No. l, Pin No. Regarding 4: Plant No. 3. Pin No. Regarding 2: It is sufficient to maximize the objective function: (20) under the constraint conditions.

[In the formula, (J, k) is the plant number of the ore storage tank. , pin NO. are shown respectively. ] Xi that maximizes the above Q,
To obtain Yi, linear programming may be used. The series information of the storage yards and each ore storage tank and the planned operation time of each system calculated by the above procedure are stored in the computer as a work table as shown in Figure 5, and when this is displayed, for example Something like Figure 6 will be displayed.

For convenience of explanation, Fig. 6 shows each storage body 1 to 1 of the two plants.
6 shows an example of inventory amount changes for 4 hours. Conventional manual dispensing plans required a lot of preliminary time, but with this method, it is possible to quickly group route conveyors by computer and optimize the dispensing plan, which only saves labor. In addition, it is possible to prevent undesirable results such as the tank running out, which is a drawback of the conventional method.

[Brief explanation of the drawing]

FIG. 1 is a schematic diagram of a group of equipment to be grouped in the present invention, FIG. 2 is a flowchart of grouping in the present invention,
FIGS. 3A and 3B are explanatory diagrams showing examples of route conveyors that are grouped according to the method of the present invention, and FIG. 4 is an explanatory diagram showing an example of the route conveyors shown in FIG. FIG. 5 is an explanatory diagram showing an example of the work table, and FIG. 6 is an explanatory diagram showing an example of the display. Y, YR・・・Storage yard, RC・・・Reclaimer, ■℃・・・Ground belt conveyor, TB
C... System belt conveyor, TRlOOI tripa, BIII ore storage tank.

Claims (1)

[Claims] 1. Select and extract the necessary raw materials from the various brands of raw materials piled up in the raw material collection area, and extract the necessary raw materials from the storage tanks of the raw material usage equipment that have been constructed in a distributed manner. In order to sort and transport the raw materials to the storage tanks, the raw materials taken out by an arbitrary take-out device selected from a group of raw material take-out devices provided in a limited number on the raw material collection and distribution site are transferred to a conveyor provided in a limited number. The raw material is delivered and conveyed to an arbitrary conveyor device selected from a group of devices, and the material is delivered and conveyed by an arbitrary dispensing device selected from a group of raw material dispensing devices provided in a limited number on the outlet side of the conveyor device section. Using a conveyance means including a plurality of conveyance lines for discharging to a storage tank, the extraction device group,
Newly selecting each of the conveyance devices constituting the conveyor device group and the raw material dispensing device group over time, changing the conveyance system by combining them, and selecting the necessary raw materials for each storage tank. In the method of discharging raw materials to be transported,
The continuous dispensing operation of raw materials is divided into arbitrary time intervals, each divided time length is defined as a sampling period, and each sampling period is regarded as a unit of control.For each sampling period, (a) each storage Current raw material inventory amount V for each tank
(b) Detect the raw material consumption amount BTONH per unit time for each storage tank; (c) From the raw material inventory amount V and the raw material consumption amount BTONH, set inventory level V for each storage tank.
Calculate the holding time until the holding time decreases to min. (f) In making the selection, select the transport equipment that is considered necessary to transport the raw material brands that need to be replenished for each storage tank from the raw material collection and distribution area to the storage tank.
(g) including transport equipment that becomes usable after (1/2) or less of the sampling period has elapsed;
By the selection, the raw material transport route from the specific brand existing part of the raw material distribution area to each storage tank is specified, and the new dispensing series is completed, and (h) the raw material transport route of the new dispensing series is used. The storage tank in which dispensing was performed during the previous sampling cycle is subject to continuous dispensing, and (i) the transport operation time Continuous operation time Y during the current sampling period of continuous dispensing work by the raw material transport route is determined by the continuous operation time Y during the current sampling cycle for all raw material transport routes under the condition that the storage amount in each storage tank is maintained below the allowable maximum storage amount Vmag. (j) Based on the above-mentioned both transport operating times A method for discharging raw materials, characterized by transporting them by rolling them.