JPS59114446A - Apparatus for measuring moisture content of particulate material - Google Patents
Apparatus for measuring moisture content of particulate materialInfo
- Publication number
- JPS59114446A JPS59114446A JP57223936A JP22393682A JPS59114446A JP S59114446 A JPS59114446 A JP S59114446A JP 57223936 A JP57223936 A JP 57223936A JP 22393682 A JP22393682 A JP 22393682A JP S59114446 A JPS59114446 A JP S59114446A
- Authority
- JP
- Japan
- Prior art keywords
- gamma
- ray
- conveyor
- neutron
- neutrons
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
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Classifications
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
- G01N23/00—Investigating or analysing materials by the use of wave or particle radiation, e.g. X-rays or neutrons, not covered by groups G01N3/00 – G01N17/00, G01N21/00 or G01N22/00
- G01N23/02—Investigating or analysing materials by the use of wave or particle radiation, e.g. X-rays or neutrons, not covered by groups G01N3/00 – G01N17/00, G01N21/00 or G01N22/00 by transmitting the radiation through the material
- G01N23/06—Investigating or analysing materials by the use of wave or particle radiation, e.g. X-rays or neutrons, not covered by groups G01N3/00 – G01N17/00, G01N21/00 or G01N22/00 by transmitting the radiation through the material and measuring the absorption
- G01N23/12—Investigating or analysing materials by the use of wave or particle radiation, e.g. X-rays or neutrons, not covered by groups G01N3/00 – G01N17/00, G01N21/00 or G01N22/00 by transmitting the radiation through the material and measuring the absorption the material being a flowing fluid or a flowing granular solid
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- Physics & Mathematics (AREA)
- Health & Medical Sciences (AREA)
- Life Sciences & Earth Sciences (AREA)
- Chemical & Material Sciences (AREA)
- Analytical Chemistry (AREA)
- Biochemistry (AREA)
- General Health & Medical Sciences (AREA)
- General Physics & Mathematics (AREA)
- Immunology (AREA)
- Pathology (AREA)
- Analysing Materials By The Use Of Radiation (AREA)
Abstract
Description
【発明の詳細な説明】
本発明は、中性子とｒ線の２つの放射線を用いた粉粒体
の水分測定装置に係シ、特にベルトコンベア等の搬送体
上の粉粒体の水分測定に好適な水分測定装置に関する。DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an apparatus for measuring the moisture content of powder or granular material using two radiations, neutrons and r-rays, and is particularly suitable for measuring the moisture content of powder or granular material on a conveyor such as a belt conveyor. This invention relates to a moisture measuring device.
石炭あるいけ鉱石等の各種の粉粒体を処理する工程にお
いて、その水分制御は製品の品質を左右する重要な要素
であシ、より正確な水分測定が要求されている。In the process of processing various powders and granules such as coal and ore, moisture control is an important factor that affects product quality, and more accurate moisture measurement is required.
水分の測定は、水分の量と中性子の検出値が粉粒体のか
さ密度一定の条件下で比例関係にあることを利用したも
のである。したがって、粉粒体のかさ密度が常に一定で
あれば、線源としては中性子を発するもので、検出器と
しても中性子のみを検出するもので十分である。しかし
、実際問題として、粉粒体のかさ密度が常にほぼ一定と
いうのは稀であシ、かさ密度には影響全受けないγ線を
用いて中性子の検出値を補正している。Moisture measurement utilizes the fact that the amount of moisture and the detected value of neutrons are in a proportional relationship under the condition that the bulk density of the powder is constant. Therefore, if the bulk density of the granular material is always constant, a radiation source that emits neutrons and a detector that detects only neutrons is sufficient. However, as a practical matter, it is rare that the bulk density of powder or granules is always approximately constant, and the detected value of neutrons is corrected using gamma rays, which are not affected by the bulk density.
通常、粉粒体はベルトコンベアで搬送されるため、ベル
トコンベアを挾み込むように線源と検出器を配置し、粉
粒体がベルトコンベア上にある状態で水分測定が行われ
ている。この場合、線源としては中性子全発する線源と
ｒ線を発する線源、検出器も中性子とｒ線それぞれの検
出器が用いられ、ベルトコンベアを含めた検出を行って
いる。Usually, powder and granules are transported on a belt conveyor, so a radiation source and a detector are arranged to sandwich the belt conveyor, and the moisture content is measured while the powder and granules are on the belt conveyor. In this case, a source that emits all neutrons and a source that emits r-rays are used as radiation sources, and detectors for neutrons and r-rays are used as the detectors, and the belt conveyor is also detected.
しかしながら、かかる構成では、中性子とｒ線による測
定位置が異なるとともに、ベルトコンベアの厚さが変化
した場合そのまま検出値に影響を及ぼすため、正確な水
分測定を行うことはできなかった。However, with this configuration, the measurement positions for neutrons and r-rays are different, and if the thickness of the belt conveyor changes, it directly affects the detected value, so it is not possible to perform accurate moisture measurement.
本発明の目的は、上記した従来技術の欠点紫なくし、よ
シ正確な水分測定が行える粉粒体の水分測定装置？提供
するにある。The purpose of the present invention is to provide a moisture measuring device for powder and granular materials that can eliminate the drawbacks of the prior art described above and can more accurately measure moisture. It is on offer.
このため本発明は、搬送体によシ搬送さルる粉粒体、中
性子とγ線の２種類の放射線を２方向に放射する線源、
前記搬送体および粉粒体を透過した中性子とγ線を検出
する第１の検出器、前記搬送体のみを透過した中性子と
γ線を検出する第２の検出器、前記第１、第２の検出器
からの出力によって前記粉粒体の水分を求める演算装置
とよ多水分測定装置を構成したものである。For this reason, the present invention provides a powder or granular material conveyed by a carrier, a radiation source that emits two types of radiation, neutrons and gamma rays, in two directions,
a first detector that detects neutrons and gamma rays that have passed through the carrier and the powder; a second detector that detects neutrons and gamma rays that have passed only through the carrier; The apparatus includes a calculation device that determines the moisture content of the granular material based on the output from the detector, and a moisture content measuring device.
以下、本発明の一実施例を図面に基づいて説明する。Hereinafter, one embodiment of the present invention will be described based on the drawings.
第１図において、高速中性子とγ線を同時に放射する線
源（例えばＣｔ−２５・２）１０全、線源容器１２に装
填し、上下方向に放射線を発する様に設定される。線源
１０から上方に発した高速中性子とγ線は、ベルトコン
ベア１４と粉粒体原料１６を透過し、検出器１８に入射
する。この検出器１８は、１個の有機シンチレータから
なるシンチレーション検出器で、高速中性子とγ線を同
時に検出する。この検出信号全前置増巾器２０で増巾し
、パルス波形弁別回路２２で高速中性子とγ線のシンチ
レーションデケイタイムの時間差を利用して波形弁別を
行い、高速中性子成分とγ線成分に分離する。この結果
全中性子カウンター２４とγ線カウンター２６で計数し
、計数値を演算装置２８に入れる。In FIG. 1, all 10 radiation sources (for example, Ct-25.2) that simultaneously emit fast neutrons and gamma rays are loaded into a radiation source container 12 and set to emit radiation in the vertical direction. High-speed neutrons and gamma rays emitted upward from the radiation source 10 pass through the belt conveyor 14 and the granular raw material 16 and enter the detector 18 . This detector 18 is a scintillation detector consisting of one organic scintillator, and detects fast neutrons and gamma rays simultaneously. This detection signal is all amplified by the preamplifier 20, and the pulse waveform discrimination circuit 22 performs waveform discrimination using the time difference between the scintillation decay times of fast neutrons and gamma rays, and separates them into fast neutron components and gamma ray components. To separate. The results are counted by the total neutron counter 24 and the γ-ray counter 26, and the counted values are entered into the arithmetic unit 28.
また、線源１０から下方向に発した高速中性子とγ線は
、ベルトコンベア１４を透過し、検出器３０に入射する
。この検出器３０およびこれ以降に接続される前置増巾
器３２、パルス波形弁別回路３４、中性子カウンター３
６、γ線カウンター３８は、上方向に透過した高速中性
子とγ線を測定する様器と同じ機能をもったもので構成
されている。この計数値も演算装置２８に入れる。Furthermore, high-speed neutrons and gamma rays emitted downward from the radiation source 10 pass through the belt conveyor 14 and enter the detector 30 . This detector 30 and the preamplifier 32, pulse waveform discrimination circuit 34, and neutron counter 3 connected after this detector 30
6. The gamma ray counter 38 is configured with the same function as a measuring device that measures fast neutrons and gamma rays transmitted upward. This count value is also input to the arithmetic unit 28.
このような透過方式の場合、透過放射線強度と被測定量
との関係は、一般に次式で表わされる。In the case of such a transmission method, the relationship between the transmitted radiation intensity and the measured quantity is generally expressed by the following equation.
■＝工。ｅ−ｐｍ−Ｐｏｔ
こ゛こに、■ ＝透過放射線強度
工。二被測定物がないときの放射線強
度
μｍ＝質量吸収係数（Ｃ４／ｇ）
ρ 二被測定物の密度（ｇ／ｌ、ｖ”）ｔ ：被測定物
の厚さく ｃｍ ）
今、粉粒体原料１６に含まれる水素量の水換算質量厚さ
’ｔ−Ｍ、、、固体成分の質量厚さｔＭ、とじ、ベルト
コンベア１４に含まれる水素量の水換算質量厚さＱＭｂ
ｖ、固体成分の質量厚さｋＭｂとすると、粉粒体原料１
６とベルトコンベア１４のトータル質量厚さは、それぞ
れ水換算質量厚さがＭｙ ” Ｍａｒ ＋ Ｍｂ−３固
体成分の質量厚さがｉ、ｙ、＝Ｍ−＋Ｍｂとなる。この
２つの被測定量を変化させ、中性子とγ線の透過率を実
験で求めると、第２図および第３図に示す結果が得られ
る。図から明らかなように、中性子とｒｆＨは、水質量
厚さの変化と、固体成分の質量厚さの両方でその透過率
は変化するが、水に対する中性子の透過率変化がγ線よ
りも大きく、固体成分については、はぼ同等の透過率変
化を示す。■ = Engineering. e-pm-Pot Here, ■ = transmitted radiation intensity work. 2. Radiation intensity when there is no object to be measured μm = mass absorption coefficient (C4/g) ρ 2. Density of the object to be measured (g/l, v") t: Thickness of the object to be measured (cm) Now, granular material Water equivalent mass thickness 't-M of the amount of hydrogen contained in the raw material 16, mass thickness tM of the solid component, binding, water equivalent mass thickness QMb of the amount of hydrogen contained in the belt conveyor 14
v, mass thickness of solid component kMb, powder raw material 1
6 and the belt conveyor 14, the water equivalent mass thickness is My" Mar + Mb-3, and the mass thickness of the solid component is i, y, = M-+Mb. These two measured quantities When the transmittance of neutrons and gamma rays is determined experimentally by changing the Although the transmittance changes with both the mass and thickness of the solid component, the change in the transmittance of neutrons to water is larger than that of gamma rays, and the change in transmittance of solid components is almost the same as that of gamma rays.
したがって、粉粒体原料１６とベルトコンベア１４の両
方を透過する中性子とγ線の透過式は、次のように表わ
すことが出来る。Therefore, the transmission formula for neutrons and gamma rays that pass through both the powder raw material 16 and the belt conveyor 14 can be expressed as follows.
■、：Ｉ、。ｅ ＋（／’ ｍｅ Ｍｗ十μＩＩａ Ｍ
＠）、９０．、、、（２）Ｉ ＝Ｉ ｅ−（μγＷ
ＭＷ＋μγｃＭＣ）、１１．９１０６．（３）ｒ
γ０
ここに、ｌｍ５Ｉｒ：中性子、γ線の透過強度Ｉ、。、
１．：被測定物がない時の中性子、γ線の強度
μｍ１．１ μゎ、：中性子の水と固体成分に対す質量
吸収係数（ＣＪ／ ｇ ）
μ、−９μ７．：γ線の水と固体成分７Ｃ対する質量吸
収係数（ｃｎｌ／ｇ ）
（２）、（３）式からＭ、、Ｍ、は次のように求まる。■, :I,. e +(/' me Mw 10μIIa M
@), 90. , , (2) I = I e-(μγW
MW+μγcMC), 11.9106. (3) r
γ0 Here, lm5Ir: Transmission intensity I of neutrons and γ rays. ,
1. : Intensity of neutrons and gamma rays when there is no object to be measured μm 1.1 μゎ, : Mass absorption coefficient of neutrons for water and solid components (CJ/g) μ, −9 μ7. : Mass absorption coefficient of γ-rays for water and solid component 7C (cnl/g) From equations (2) and (3), M, , M are determined as follows.
・・・・・・・・・（４）
・・・・・・・・・（５）
一方、線源１０から下方向に発し、ベルトコンベア１４
のみ？透過する中性子とγ線の透過式は、次のように表
わすことができる。・・・・・・・・・(4) ・・・・・・・・・(5) On the other hand, radiation is emitted downward from the radiation source 10, and the radiation is transmitted to the belt conveyor 14.
only? The transmission formula for transmitted neutrons and γ-rays can be expressed as follows.
エ ｉ ：Ｉ／、 、、 （１”ｍｖ Ｍｂｖ十μｍｂ
Ｍｂ ） 、０００．、、、、（ｅ）エ ｔ ＝
＝ ｉ ｒ ｅ−（μｍｗＭｂｖ＋μＩｂ Ｍｂ ）
、、、 、、１６１．（カｒ ｒに
こに、Ｉ！、Ｉ： ：中性子、ｒ線の透過強度■。−
ＩＩ；＠：被測定物がないときの中性子、γ線の強度
μ、ｂ、μ、ｂ：中性子とγ線の固体成分に対する質量
吸収係数（ｏＪ／ｇ）
（６）、（７）式からＭｂｗ ＨＭ ｂは次のように求
まる。D i :I/, ,, (1”mv Mbv 10μmb
Mb), 000. ,,,,(e) t=
= ire−(μmwMbv+μIbMb)
, , , , 161. (Karr r smile, I!, I: :Transmission intensity of neutrons and r-rays■.-
II; @: Intensity of neutrons and γ-rays when there is no object to be measured μ, b, μ, b: Mass absorption coefficient for solid components of neutrons and γ-rays (oJ/g) From formulas (6) and (7) Mbw HM b is determined as follows.
・・・・・・・・・（８）
・・・・・・・・・（９）
以上の結果から、粉粒体原料１６のみの水換算質量さと
固体成分の質量厚さは、
Ｍ、ｖ＝ＭＷＭｂＷ＋＋＋、＋、４１）Ｍ−＝Ｍ、
Ｍｂ ・・・・・・・・・（ｌ
υとなるから、粉粒体原料１６に含まれる水分曽の重量
％は、次式で求められる。・・・・・・・・・(8) ・・・・・・・・・(9) From the above results, the water equivalent mass of only the powder raw material 16 and the mass thickness of the solid component are M, v=MWMbW+++, +, 41) M-=M,
Mb ・・・・・・・・・(l
Since υ, the weight percent of water contained in the powder raw material 16 can be determined by the following formula.
またベルトコンベア１４の測定位置の同期をとるため、
ベルトコンベアの駆動ローラー４０から回転数全検出し
、変換器４２で電気信号に変換し、演算装置２８に入力
する。演算装置２８で、ベルト位置の同期をとりα〔、
α９式の演算？行う。In addition, in order to synchronize the measurement position of the belt conveyor 14,
The total number of revolutions from the drive roller 40 of the belt conveyor is detected, converted into an electrical signal by a converter 42, and inputted to the arithmetic unit 28. The arithmetic unit 28 synchronizes the belt position α[,
Calculation of α9 formula? conduct.
第４図は第１図に示す構成を単純化したものである。す
なわち、それぞれの検出器２０．３２の信号を信号切換
回路４４に入ｒ１．、演算装置２８の一定時間ごとの切
換指令によシ、検出信号を切換えてパルス波形弁別回路
２２に入れる様圧するとパルス波形弁別回路２２、カウ
ンター２４．２６は１組で構成できる。FIG. 4 is a simplified version of the configuration shown in FIG. That is, the signals of the respective detectors 20.32 are input to the signal switching circuit 44 r1. If the detection signal is switched and input to the pulse waveform discrimination circuit 22 according to a switching command from the arithmetic unit 28 at regular intervals, the pulse waveform discrimination circuit 22 and the counters 24 and 26 can be configured as one set.
この構成は、ベルトコンベア１４の質量変化全常時補正
する必要のないときに有効である。This configuration is effective when there is no need to constantly correct mass changes in the belt conveyor 14.
以上本発明は、中性子とｒ線の２種類の放射線を発する
線源上用い、搬送体のみおよび搬送体全粉粒体の両者を
透過させるように構成したため、中性子とγ線の透過場
所が同一となシ、シかも搬送体の厚さの変化の影響？受
けることがなく、よシ正確な水分測定ケ行うことができ
る。As described above, the present invention is used on a radiation source that emits two types of radiation, neutrons and r-rays, and is configured to transmit both only the carrier and the entire carrier powder, so that the neutrons and gamma rays pass through the same place. Is it affected by changes in the thickness of the carrier? It is possible to perform very accurate moisture measurements without having to be exposed to water.
第１図は本発明になる水分測定装置を示す概略図、第２
図は水質量厚さと中性子、ｒ線の透過率との関係？示す
図、第３図は固体分の質量厚さと中性子、γ線の透過率
との関係を示す図、第４図は信号処理部の他の実施例？
示す図である。
１０・・・線源、１２・・・線源容器、１４・・・ベル
トコンベア、１６・・・粉粒体、１８．３０・・・検出
器、２０゜３２・・・前置増巾器、２２．３４・・・）
（ルス波形弁別回路、２４．３６・・・中性子カウンタ
ー、２６゜３８・・・ｒ線カウンター、２８・・・演算
装置、４０・・・３０
ＩFig. 1 is a schematic diagram showing a moisture measuring device according to the present invention;
Is the diagram the relationship between water mass thickness and neutron and r-ray transmittance? Figure 3 is a diagram showing the relationship between the mass thickness of the solid component and the transmittance of neutrons and γ-rays, and Figure 4 is another example of the signal processing section.
FIG. 10... Radiation source, 12... Radiation source container, 14... Belt conveyor, 16... Powder, 18.30... Detector, 20° 32... Preamplifier , 22.34...)
(Russ waveform discrimination circuit, 24.36...neutron counter, 26°38...r-ray counter, 28...arithmetic unit, 40...30 I
Claims (1)
種類の放射線ｔ−２方向に放射する線源、前記搬送体お
よび粉粒体を透過した中性子とｒ線會或出する第１の検
出器、前記搬送体のみを透過した中性子とγ線を検出す
る第２の検出器、前記第１、第２の検出器からの出力に
よって前記粉粒体の水分を求める演算装置とよシ構成し
たことを特徴とする粉粒体の水分測定装置。1. Powder and granular material transported by a transporter, 2 of neutrons and r-rays
A radiation source that emits the type of radiation in the t-2 direction, a first detector that emits neutrons and r-rays that have passed through the carrier and the powder, and detects the neutrons and gamma rays that have passed only through the carrier. A moisture measuring device for a powder or granular material, characterized in that the device comprises a second detector for detecting the moisture content of the powder or granular material, and an arithmetic device for determining the moisture content of the powder or granular material based on the outputs from the first and second detectors.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP57223936A JPS59114446A (en) | 1982-12-22 | 1982-12-22 | Apparatus for measuring moisture content of particulate material |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP57223936A JPS59114446A (en) | 1982-12-22 | 1982-12-22 | Apparatus for measuring moisture content of particulate material |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| JPS59114446A true JPS59114446A (en) | 1984-07-02 |
Family
ID=16806022
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP57223936A Pending JPS59114446A (en) | 1982-12-22 | 1982-12-22 | Apparatus for measuring moisture content of particulate material |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPS59114446A (en) |
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US5446288A (en) * | 1993-10-25 | 1995-08-29 | Tumer; Tumay O. | Integrated substance detection instrument |
| US5557108A (en) * | 1993-10-25 | 1996-09-17 | T+E,Uml U+Ee Mer; T+E,Uml U+Ee May O. | Integrated substance detection and identification system |
| US11280748B2 (en) * | 2012-10-22 | 2022-03-22 | Troxler Electronic Laboratories, Inc | Conveyor system and measuring device for determining water content of a construction material |
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|---|---|---|---|---|
| JPS5317784A (en) * | 1976-07-31 | 1978-02-18 | Aloka Co Ltd | Continuous measuring apparatus for suspended dusts |
| JPS5522700B2 (en) * | 1974-07-10 | 1980-06-18 | ||
| JPS5763439A (en) * | 1980-10-03 | 1982-04-16 | Nippon Steel Corp | Moisture measuring device of charged material for iron manufacture |
-
1982
- 1982-12-22 JP JP57223936A patent/JPS59114446A/en active Pending
Patent Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS5522700B2 (en) * | 1974-07-10 | 1980-06-18 | ||
| JPS5317784A (en) * | 1976-07-31 | 1978-02-18 | Aloka Co Ltd | Continuous measuring apparatus for suspended dusts |
| JPS5763439A (en) * | 1980-10-03 | 1982-04-16 | Nippon Steel Corp | Moisture measuring device of charged material for iron manufacture |
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US5446288A (en) * | 1993-10-25 | 1995-08-29 | Tumer; Tumay O. | Integrated substance detection instrument |
| US5557108A (en) * | 1993-10-25 | 1996-09-17 | T+E,Uml U+Ee Mer; T+E,Uml U+Ee May O. | Integrated substance detection and identification system |
| US11280748B2 (en) * | 2012-10-22 | 2022-03-22 | Troxler Electronic Laboratories, Inc | Conveyor system and measuring device for determining water content of a construction material |
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