CZ567789A3 - Method of increasing accuracy or reliability of measurements in instruments used for measuring characteristic properties of bulk materials and apparatus for making the same - Google Patents

Abstract

This invention concerns a method and apparatus for auditing the means of measuring one or more variables which affect the accuracy or the reliability of the results obtained by devices used to measure particular characteristics of a bulk material, especially during handling and processing, and when said characteristics are measured on an aliquot extracted from said bulk material, a method and an apparatus for concurrently auditing one or more variables affecting the accuracy or reliability of the means for extracting an aliquot of said bulk material.

Description

The present invention relates to a method of checking accuracy or reliability. The measurement of the measurement of the erosion 141 is 11% / h / py. λ '/ 55 ° Gosh properties dn' gečř sypnýeh materials ^ ;, from CR and C Unni ^- to perform -tohoto for extended-g

For bulk bulk materials such as bauxite, elemental sulfur, phosphates, gypsum, limestone, cement, iron ore, pelletized iron ore, maize, wheat and other grains, sugar, coal, lignite, peat, anthracite, waste · · sewage sludge , wood chips and bark and paper are typically measured for different characteristics, particularly during transport or processing, either directly or indirectly on an aliquot sample taken to accurately contain each variable component present in the total amount of said material in the same ratio and in the same physical and the chemical state in which it is present in the total amount of this material. The value of such materials in the United States is high. For example, in the forest product group that is included in Standard Industrie! Class 26, the total value of supplies in 19 £ c was approximately $ 108 billion. Of this amount, $ 4.1 billion was spent on pulp mills, $ 42 billion for paper mills and cardboard factories, $ 23 billion for newsprint manufacturers, $ 14 billion for corrugated and straight cardboard cartridges, $ 11 billion for sanitary paper products, and for Sanitary Food Packaging $ 3 Billion »Coal is a longer bulk bulk material that regularly measures various characteristics, and in rcc? By 1986, the forecast for coal mining and processing in the United States was approximately $ 23 billion.

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With other bulk materials, nitrogenous and phosphate engineered fertilizers account for about $ 9 billion a year, ns of first-melting metals to pC of up to $ 60 billion, and inorganic chemicals for about $ 12 billion. In 1966, approximately 4 billion dollars of cement were produced in the United States.

Iri handling and processing some of these hromadnvch svpnycn έΐ s všsk čoctčrč zpsčr to ^c ^ n ChV H & R ^ 3 Ni slikvotních samples ns, which is measured above properties, notably in terms of weight mncžsoví spaných bulk materials.

. <cnysa.m occnazz ur oor jor.ýca enarsmoer ´C Ί in; cn sxaxec.n comecn operated from cdcncnc, e zCCC smdecz winter.

• 3 pO dark need el electric businesses serving public 22.9 billions dollars. Stocks of coal in the elec render continuous about 163 millions tonnes in nominal h

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ip * o exes.ti ^- icnè; _cniuy rocnt odepz ^ ujx to o V; due to its inability to declare the quantity of coal purchased. 3 péi en utli · 2 to to · č r p oč pouze pouze pouze pouze pouze pouze pouze pouze pouze pouze pouze pouze pouze pouze pouze pouze _v čclarúo rorivečí zero pj. čktuCkj Π (ryOGiGHc ZhiZ2 VC 0 * V y KJ. (ť ΐΐ CuoOYpZ Υόο ILC-2. GVčJOYSntE V ww C Ω0 G6 S U. 4 JL 2. u * j C pp * ¹ GuS J1 uy t O <j νΓ hXv V 5 V t U ΐ Γ3 pž p3? U3 c U Three born oxides, but rather inaccuracies in weighing, sampling with ease. · General, weighing errors and sampling increase, with decreasing amount of material to be weighed From or from: the sample is squeezed Errors that occur tend to increase as the maximum material handling operations are carried out at less than full capacity.

Warehouses are rs-sulfurized and other oclasxi than mere rigging stocks. For example, inaccuracies that result in an overestimation of actual inventories must be compensated by providing an extra amount needed to meet the necessary needs. The costs of buying, storing, interest and insurance are very real, though not exactly quantifiable for the lack of more accurate figures. The further increase in expenditure is related to the lack of more accurate and timely quality information. By way of example, the impact of a forced reduction in the performance of equipment 2 from xonc resulting from external purchases of en-ergi, losses associated with less than ideally economic supplies, and operations with coal of better quality than is actually necessary to comply with air quality regulations . As already mentioned, these economic losses cannot easily be estimated due to the lack of more accurate information and timely information; but they are considerable. The same problems arise in other bulk bulk processing industries where financial darkness scuvzsejrc:

At the end stations where bulk bulk materials pass, both on export and import markets, there is a considerable need for irradiation in 1986 for approximately 300 million samples and weighing. The United States produced $ 4 billion of cement and imported it dollars. The value of shipments of metals and utility minerals cations dollars.

million tons included in Classes 10 and 14 of the Industrial Glsssifi standard, excluding fuel, amounted to 23 billion in 1986

Imports reached $ 3.2 billion. The coal industry exported coal valued at $ 3.5 billion.

The invention relates to a method and apparatus for controlling and documenting operating variables or manifestations of such variables and the results obtained from different parts of the apparatus used to measure one or more characteristics of bulk bulk materials in order to verify that the accuracy and reliability of the results, obtained by such measuring devices have not been influenced by variables which may affect the reliability of the measuring devices. In doing so, it is very useful to compare the measured properties concurrently with the measurement of the variables that can affect the accuracy of the results obtained by the devices used to measure the properties of the bulk materials with the respective reference values.

The invention also relates to a method and apparatus for controlling and documenting operating and external variables or for the phenomenon of such variables, which may affect accuracy and convenience of the apparatus used to collect an aliquot of bulk material, which aliquot should accurately sanitize each component present in the whole amount of the above-mentioned 3 d Π c 53 OS ptl · 3 33 ^ 33 X ^ 3 ?! 3.GL 13 V * t é IL Z L'C ΓΠ 3? Of the chemical state in which these constituents are present in the total bulk of the bulk bulk material from which the aliquot has been taken, to verify that: accuracy and reliability aiikvotr.ího samples was unaffected by variables which can influence the accuracy and reliability of said devices for taking a sample _{of T} alikvotníhb ríovněž -souuěžnč it is very useful to compare said operational and surroundings related variables with the respective values of tert reneními.

The purpose is to:

roto rinsing zousoo ε equipment for verifying the accuracy and reliability of the equipment for reading the sample »ad- x z.‘ ml

Another object of the invention is to provide a method for verifying the accuracy and opacity of the results obtained by measuring the various characteristics of a bulk cell.

It is also an object of the present invention to provide such a method and apparatus that makes it possible to concurrently compare said wasted operating and environment-related variables with one or more suitable Π VILIs. J- - ** - 3 A 113 Π j -33 3 * r-1 ·? t p ď i x £ x 3 Ο 0Ω O l o lil 3. O 3 KY t 2 O X IYLYC 'ZOÚS' control which allows simultaneous comparison of both measured property; the resultant obtained by obstructing the variables of the causes decreases from the living s?

• -nim. utereno ή ^r> the zi it obstructs shall know ^ ypného bulk material, with at least a suitable barley> good reference value.

observation of the prcvccic prc or noncurrent variables and comparison with suitable reference. Values are enabled by devices for improved control of operations by feedback in pre-selected bladders over control of container level control, calibrated chute or material flow rate sensor, and for signaling conditions outside permitted limits that may require operator intervention to correct or adjustment.

Yet another purpose of the invention is to provide a device for improved feedback control and for signaling operating conditions outside selected limits that may require operator intervention for correction or adjustment.

These, together with other purposes and advantages of the invention, will be explained in more detail with reference to the accompanying drawings.

Giant. 1 shows a schematic invention applied to the conveyance of coal from receiving in a hopper from a mine until it is removed from the landfill pile for feeding to the burner.

Giant. 2 schematically illustrates the invention applied to gradual beard-on-beard zonation scrubbing pens, an in-line analyzer, a weight delivery conveyor, and an extension.

Giant. 3 is an enlarged detailed diagram of the coal treatment in a typical mechanical sampling system illustrated in FIG.

Figure 4 is a schematic representation of the computer's operating software (software) and the peripheral equipment used to receive, store and analyze data obtained from the individual

era signal a Z <2 Z Ω £ lu £ Cl Λ ^; - ς, ^ · incorrect operation wants with Seinani bulk status bulk daughters video exchangers and printed prints

for comparison with major video computers.

While the invention has been described with particular reference to the use of coal in electrical utilities serving the public, it can equally be applied to other bulk material as mentioned above.

All components of the device of the invention, with the exception of operating equipment (software) for a particular installation, are commercially available components on the market today.

FIG. 1 shows an unloading device comprising a hopper on a rail track. The coal falls from the hopper 10 to the crusher 11 and from there onto a belt conveyor 12 running through a belt weigher 1, into a mechanical sampling system 14. Coal not taken in the mechanical sampling system 14 is carried up by a belt conveyor 15 ε is then emptied no. stock heap

The rail hopper 10 is typically provided with a coarse sieve represented by a bar grate having apertures of approximately 0.09 m 2 to prevent excessive pieces and large lumps of frozen coal from trapping in the assembly. Such pieces are broken either manually or in special crushing plants. While in the drawing, for the sake of clarity of the invention, a hopper 10 is shown as it discharges coal directly into the crusher 11, in practice the flow of coal from the hopper 10 is controlled by means of metering conveyors.

Typically, auxiliary devices around power stations are designed to process coal of a maximum of 5 cm. The main purpose of the crusher 11 is to reduce the maximum size of the coal so as to comply with this operating requirement. The belt weight 13 is an officially certified commercial scale. This means that the weights obtained there are for the purpose of paying to coal suppliers. Sensor 17 is positioned on crusher 11, sensor 18 is belt weigher, sensor 19 is on mechanical sampling system 14, sensor 20 is on belt conveyor 2, and sensor 21 is on belt conveyor 15. These sensors include one or more specific sensors as described in the following, and are connected to the inlet and outlet electrical objects 22-22 with the appropriate suitable recording and tracking devices shown in FIG. 4. The coal from the storage heap 16 can be removed as needed by a conveyor 23.

The coal from the conveyor 26 in FIG

24, again passing over another belt weight 25 o This belt νέ ^to É2 is generally an officially verified weight, but is not used as commercial. Instead of tone, it is used to determine the mass amount of coal burned by the Union falling into the bunker 26 from the end of the conveyor, and a reasonable amount is taken in the sampling mechanism 27, a typical mechanical sampling system, usually identical to the 14 mechanical sampling system. the Coal sample then runs through an in-line analyzer 28, via the vein conveyor!

2 and the pulverizer jC into the burner 31. Here, too, ciomo 26 is adjusted to the copolymer, crc = c to the ligament mp, cc. on a conveyor belt 24. a sensor 35 on the mechanical sampling system 27, a sensor 36 on the bunker 26, a sensor 27 on the inlet of the lyser 26, a sensor 36 on the weighing conveyor 2? and sensor 35 n linear: jc j _; a few soecibical targets, even hands described in caic, are connected to the input and output wires of the liaison with the respective repressors: and the monitoring of the carbon recovery is traditionally carried out on the basis of an analysis in an ingressed state (wet) o This practice is the source of many discussions between buyer and seller. The moisture component is subject to runoff and evaporation losses and is increased by rainfall or snowfall. In the north, frozen coal is a constant problem Often there is a blockage when wet non-frozen coal comes into contact with metal mandates whose temperature is below the point of precipitation.

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cel j / 7, 1b, ± *, ^ 3, 22. ^& ÍSl uses ie securing and continuous recording in real time? data and time stamps, ambient temperature and metal surface temperature of the crusher, belt weigher 13, mechanical sampling system 14, weighing scale 25, mechanical sampling system 27, bunker 26 of an in-line analyzer 28 of the weighing conveyor 29, as well as and relative humidity in the grinder 11 and the mechanical sampling system 14. These data verify the temperature and humidity conditions for reliable and accurate operation of the sampling and weighing systems, and allow an alarm to be generated under conditions that could cause operating problems or equipment malfunction.

Bulk bulk materials, such as the Union, are occasionally contaminated with foreign materials that can damage the device. Caution should be exercised in coal as it may contain anything that detonates after broken parts, railcars. Magnetic sepsrants are provided in coal handling equipment, preferably as close as possible to the beginning of the handling process so that the device is protected by such foreign sensors 17, 18, 18, 18 from iron chips. Despite these measures, the movable equipment occasionally damages:

and 39 are used to monitor and continuously record, in real time, data and time stamps, the rate and type of vibration and noise and its composition at the crusher 11, the belt weighing system 13 for mechanical sampling, the belt weighing system 25 for mechanical sampling of the sample and pulverizer 30 to verify operating conditions for reliable accurate operation of the sampling and weighing systems. This creates additional possibilities for detecting excessive or unusual conditions that could adversely affect taking an aliquot or sample and weighing, and also allows the alarm to be set up for conditions indicating operational problems ^{3 for} possible equipment malfunction. There is no exact boundary between audible frequencies and mechanical vibrations, but in general, mechanical vibrations associated with rusty machinery are below audible fractions; therefore both audible frequencies and mechanical vibrations are monitored and continuously recorded and compared with the appropriate reference values. This also makes it possible to detect the neglect of operators in the event that the continuous flow of coal is impeded.

Hammer crusher product is greatly influenced by the peripheral speed of hammers »The peripheral speed depends on the rotation speed o The load, voltage and power or current drawn by the crusher motor all affect the rotation speed · Mostly the motor temperature is affected by the load and voltage. Both the vibration, the noise level is affected by the rotational speed. The sensors 17, 12 ³ 22. serve to monitor and continuously record, in real time data and time stamps, the rotational speed as well as the magnitude and frequency of the vibrations and sounds resulting from the crushers 11 and the crushers which are part of the mechanical sampling systems 14 and 27. These sampling systems are described in detail below with respect to: cbr _o 3 »in addition, other variables, ie voltage, current, power and motor temperature, are recorded using real-time sensors 17, 19 and 22 ^with date and time stamps for verification prevoznic; condition for reliable operation of these crushers. This offers another possibility for not excessive or unusual troubles that bv

- 13 could have an adverse effect on sampling and weighing, and allow the alarm device to be set for conditions indicating operational problems and possible malfunction of the device. It also provides the possibility of diagnosis allowing the removal of equipment faults.

A part of the sampling device 14 and 1 is shown in detail in FIG. 3, a typical two-stage mechanical sampling system is shown schematically. It consists of a primary cutting device 40, a primary feeding conveyor 41, a sample crusher 42, a secondary cutting device 43, a sample collecting container 44-44 ns, a circular conveyor 4? and weights χό per sample. Appropriate term / z szmuzovs coal blends by the system of orcs. The lyosti is also usually a step system, z z * *. ž ~? Z C Σ. £ 2? 3. Ώ 0 2? ZC C 3 O · • p, v - ·? z, \ Thr * · r -n '—‘v ‘-’ν - · * handling grease n: varies according to particle size distribution, moisture content and relative amount of impurities. Angles belong to the most difficult to manage - at 0.3 per sec. Of airborne bulk materials. This is the result of incremental crushing and disruption within the collection system. which changes the handling properties of the material and reduces the grinding speed of the comminuted sample to such an extent that friction,

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Coils and artifacts, such as maintaining coal in the computer, are potentially serious sources of error on the sampled sample. When such conditions occur, sampling systems often fail physically. The operator must then pound chutes, cutting mechanisms and crushers with heavy tubes and sledgehammers to restore coal movement. Such failure fails to adversely affect the operation of the sampling system.

Seats 47, 4S, 45, 50, 51, 52 and 53 with 54 serve for monitoring and continuous recording, in real time by data and time stamps, metal surface temperatures, vibrations and vibrating patterns, sounds and sound diagrams on connecting troughs, covers of individual components, circular conveyor? for the 46 weighing scale, to demonstrate and verify operating conditions for reliable and accurate sampling. This surveillance makes it possible to set the alarm device to conditions' indicating operational problems and possible malfunctioning of the device or its failure, as well as the possibility of diagnosis to eliminate faults and malfunction of the device. These sensors comprise one or more specific sensors as will be described below, and are connected to input and output power lines 55 to 55 with oříslušnými appropriate recording and monitoring devices shown: in Fig. 4 by? C and _b? cav _v ; Kle used ex.

There are two basic merhc

taking aliquot samples bulk sy pný timewise n on a weight basis. For both types ode they write national and international D 0 x * Η Í P P P her

the number and minimum weight of the required samples, which are proportional to the weight of the whole quantity of the entire batch to be represented by the aliquot.

In order to maintain the same ratio of the quantity of the individual variable components in the sample as that of the whole, the sample separators cutting or removing the sample must move at a constant speed. , the same for each sample

When sampling on a weight basis, samples are taken at evenly defined quantities by weight and rychlcs cutting device must vary in direct proportion to changes in the speed of movement of the coal in order to maintain the same ratio of each component of obstructions in the sample which is the whole amount _of

Serious errors can occur when sampling time and weight based scales if the cutting system displacements occur synchronously with the linear changes in quality over time or by weight, or if the displacements of the secondary or tertiary cutting apparatus intersect synchronously with the previous 3

Linear quality changes · based on time or weight are often related to changes in the speed of coal movement that ορ-št may reflect the limited capacity of the ripening system

- 16 materials related to the changing handling properties of bulk bulk material. The crushers also cause linear quality or time-to-weight changes, which can be attributed to the fact that the more easily crushable material is crushed first.

Thus, to verify the operating conditions for accurate and reliable time-based and ns-based weight sampling, the 47, pi and 2c sensors have been modified to detect the number of displacements of the primary h: cutting device 4C and secondary cutting device 4.3 ^ε measured: 41 also for measuring and recording, in real time by time and chat stamps, the time at which the cutting mechanism is shifted, the lengths being:

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sunu. oro detection and allows the market ^- strsnit rt £ · - · y. * / - 7 if r <= zr.á device working synchronously,

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monitoring of continuous recording, real-time data in the movement of coal, voltage with the frequency of the supplied electric current, ambient temperature, vibrations, and as belt operation weighing 13 and χ 5, sk checking the flow rate of the coal 14c and 17 and checking the synchronization of the changes in the movement of the coal with the displacements of the cutting devices.

Sensors 20, 21 in Figs. 1, 12 and 34 in Figs. And 56 on Fig. 3e use to monitor and continuously record, in real time data and time stamps, conveyor belt speed, voltage, current (or power) to drive motors for conveyor belts or motors for hydraulic auxiliary equipment to detect defective conditions on conveyors 12, 15, = 2> 24 and 41.

All conveyors of modern systems: with bulk gritters the materials are interlocked to prevent the operation of any conveyor in the system in front of another conveyor that is not currently in service. For this reason, the sensors monitoring the status of the control devices are an alternative to the above-mentioned sensors recording conveyor speed, voltage, etc. information.

I am bound by mbteriaiu in pchyou senem donraw introduces numerous variables that can affect the accuracy of weighing. These also include the flexibility q of the belt tension. Temperature also affects analog and digital electronic devices, many existing belt scales use mechanical devices to measure belt movement (load) as well as integrate belt speed with load. Newer technologies use electromechanical and electronic devices to measure the speed of time and the magnitude of the load, as well as integrating the belt speed with the load. The accuracy of these devices is vulnerable to radio frequency (BFI) and electromagnetic interference (Tkl) interference, as well as to voltage and frequency fluctuations, both mechanical and electronic scales

- 18 are affected by sagging of the belt between adjacent guide rollers and vibrations, which may be caused, for example, by the joining of the belts n <

near to the running devices, i.e. the sampling systems and the crushers.

The accuracy of the belt weigher is also influenced by the load level. In commercial scales, the load is limited by the provisions set out in the National Bureau of Stancar Handbook 44 to a range of 35 to 100% of the nominal capacity. Alarm devices must be provided to signal traffic above these limits.

The sensors 18 s 33 are used for monitoring with continuous recording, real-time data and time stamps, coal advance rate, voltage and frequency of incoming electric current, ambient temperature, vibration and bandwidth operating time. The information for the respective conveyors 12 and 24 is important for verifying the validity of the weighing without adversely affecting the factors thus measured.

The value has two dimensions, quantity (weight or number) and quality (valuable characteristics or components). Spcif? ' The Company requires, through laws and regulations, that weighing for payment be carried out by ureenc-overenyen vanneu.

Subscribed ?! bulk bulk material sampling is a complex and difficult task for which the need for accuracy, fairness and reliability in general has not achieved the same broad recognition of companies,

c. continuous calorimetry.

- 19 as in weighing. As a result, no similar statutory or verification regulations apply to ns sampling, but there are national and international voluntary agreed sampling standards that are widely used in trade and are mentioned in contracts and agreements.

The introduction of an embedded analyzer puts bulk material handling and handling at the threshold of a new era in which the state of receipt, inventory, and use of subscribed material can be reported in real time with valuable components or special parameters as well as more conventional conventional mass units, such as tons or pounds, Typically, for example, electric utilities serving the public have hitherto refrained from keeping records of receipts, stocks and the use of coal, expressed in terms of calorific value in British thermal units (ZTc), which is a valuable property of the Union. The introduction of in-line analyzers capable of providing this information in real time will eliminate this problem. The in-line analyzers currently available use X-ray fluorescence, microwave analysis, moisture-nuclear magnetic resonance analysis gamms neutrons průběžnc activated;.: i uamma patrsk. ·, ~ '.z $' becomes achieved: c ^ t ^ lnvm stsncv R.I taprsky and-nelýzv

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azenom aηnlysátu 26 and to: TO.' . , Λ <1 just prijimanycn, sk -k 8 C, pných Material: 2Ϊ0

The computer and the associated operating software (software) is described in the following with reference to Fig. 4.

uvaaan *, which has been discussed above, go beyond the ones, texts and regulations that adversely affect the accuracy and reliability of officially verified in <

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By collecting samples and in-line analyzers, measuring and continuously recording these factors in real time, the accuracy of weighing can be verified to a greater extent than previously possible. By similar guarding, machine sampling and embedded analyzers, compliance with applicable standards of sampling and testing, accuracy, accuracy, and accuracy may be increased.

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r. i U- .. i ...., om.bination with verified weights:

as achieved by the verified, such sampling can effectively provide immediate valuable results having a verified status.

In Z- i-— - o

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2θ of powered discs: o.-. Arnsr. o..-moj-uny vsti a '. · ηί'θ1ηζn ^- .'mi including:

- is shown in matiothioids;

The line 6h is likely to be very low-power: 2lL> once do not teach several power lines down the mcculatr-cemoeniatcr c <m

With the control of its own operating equipment (software), which is common to the individual sensors in the system via multiple analog and digital input output channels that modify the input signals. The computer £ 7 is equipped with an electronic nodinsmi-calendar, powered discs for continuous recording of sensor readings, and the necessary interfaces for a modulator-democulator, a printer, and a video terminal keyboard.

The computer software provides many services. Converts sensor signals into real, world-wide units, if necessary, directs continuous logging of sensor data to a database maintained by a system of 56 powered drives with date and time stamps from an internal electronic clock with calendar analyzes sensor data by comparing to predetermined parameters It controls the sampling operation in synchronization and activates the black and audible charging devices for any tires beyond the preselected limits or requiring operator attention or clack.

Appropriate parameters can be selected as appropriate reference values for comparing both the data obtained from bulk bulk material measurement equipment and the variables measured in parallel with bulk bulk material measurement. lacquer parameters are, for example: - contract, equipment and operation specifications, operating and material standards, purchasing and acceptance specifications /, boundaries and limits imposed empirically and resulting from trials,

Claims (1)

The operating equipment (software) also checks whether the bulk bulk material received is within prescribed qualitative and quantitative limits, and recalculates the receipts, custody records for world-weight units, valuable components, valuable properties, and monetary units. provides the necessary services for inputting biographical data to the keyboard and protects the security of access to various: operating data (software) through predetermined priority levels. The operating equipment (software) provides interrupt, failure, status, operation, as well as diagnostic messages locally and at remote terminals in the main office and repair shop. Operating equipment (software) also provides inputs and outputs to other computers · The equipment of this invention by the machinery is site specific and must be adapted to the specific needs of each workplace. It is desirable that the computer program instruction code be a modular input code to facilitate such adaptation. While the invention has been described in its preferred embodiment, it should be noted that it may be subjected to various changes without departing from its scope and invention. Ού 5677-89 D