JPH07120387A - Detection of clouding point by automatic tester - Google Patents
Detection of clouding point by automatic testerInfo
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- JPH07120387A JPH07120387A JP26863893A JP26863893A JPH07120387A JP H07120387 A JPH07120387 A JP H07120387A JP 26863893 A JP26863893 A JP 26863893A JP 26863893 A JP26863893 A JP 26863893A JP H07120387 A JPH07120387 A JP H07120387A
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- temperature
- sample
- cloud point
- light
- tank
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Abstract
Description
【０００１】[0001]
【産業上の利用分野】本発明は、石油製品の自動曇り点
検出方法に関する。BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an automatic cloud point detection method for petroleum products.
【０００２】[0002]
【従来の技術】曇り点は、石油製品を規定の方法で試料
をかき混ぜないで冷却したとき、パラフィンワックスが
析出あるいは、分離し始める温度を表し、原油の種類、
脱臘の程度、流動点降下剤使用の有無などを知る上で重
要な試験であり、日本工業規格ＪＩＳ，Ｋ−２２６９に
規定されている。2. Description of the Related Art The cloud point represents the temperature at which paraffin wax begins to precipitate or separate when a petroleum product is cooled by a prescribed method without stirring the sample.
This is an important test for knowing the degree of stripping and the use of pour point depressant, and is defined in Japanese Industrial Standard JIS, K-2269.
【０００３】従来の自動曇り点試験法は、曇り点のわか
っている試料を用意し、この試料を実際に自動により測
定し、曇りを生じる温度に達した時点で曇り度合いをみ
て感度の数値を設定していた。In the conventional automatic cloud point test method, a sample having a known cloud point is prepared, the sample is actually automatically measured, and when the temperature at which cloud occurs is reached, the cloudiness is observed and the sensitivity value is calculated. Had set.
【０００４】試験は、予期曇り点を設定後、その温度よ
り１４℃高い温度に試料を加熱し、冷却操作にはいる。The test involves setting the expected cloud point, then heating the sample to a temperature 14 ° C. above that temperature, and entering the cooling operation.
【０００５】予期曇り点の１０℃手前の温度の時投光器
と受光器との間の光量が測定スタート値Ｍとしてメモリ
ーされ、あらかじめ設定した感度％Ｐと次式により測定
基準値を決め、測定基準値より光量が外れた時の温度を
曇り点として検出している。 曇り点検出の測定基準＝Ｍ＋Ｍ×Ｐ×１／１００〜Ｍ−
Ｍ×Ｐ×１／１００ Ｍ：検出スタート時の光量（ｍｖ） Ｐ：感度％ 表１に上記従来の自動曇り点試験法による測定結果を例
示する。When the temperature is 10 ° C. before the expected cloud point, the amount of light between the light emitter and the light receiver is stored as the measurement start value M, and the measurement reference value is determined by the preset sensitivity% P and the following equation. The temperature when the light intensity deviates from the value is detected as the cloud point. Cloud point detection metric = M + M × P × 1/100 to M−
M × P × 1/100 M: Light amount (mv) at the start of detection P: Sensitivity% Table 1 exemplifies the measurement result by the conventional automatic cloud point test method.
【０００６】表１は同一油種の軽質軽油を用い、予期曇
り点と感度％（Ｐ値）を試料Ｎｏ．１〜６の夫々に対し
て表の如く設定した場合の自動検出法による“自動曇り
点”と手動法（ＪＩＳ規格）による“手動曇り点”の結
果を比較したものである。手動曇り点は試料の夫々に対
して同一曇り点を与えるが、自動曇り点は試料Ｎｏ．
３，Ｎｏ．４およびＮｏ．６で異なる値を与えている。Table 1 shows that the lightening oil of the same oil type was used, and the expected cloud point and the sensitivity% (P value) were measured for the sample No. It is a comparison of the results of the "automatic cloud point" by the automatic detection method and the "manual cloud point" by the manual method (JIS standard) when the settings are made as shown in the table for each of 1 to 6. The manual cloud point gives the same cloud point to each of the samples, while the automatic cloud point gives the same cloud point.
3, No. 4 and No. 6 gives different values.
【０００７】この検出方法では、予期曇り点の入力が
適正でないと、誤差原因となるため未知試料には使えな
い。油種にあった正しい感度の入力が必要である。な
どの問題点があり、真値のでる検出方法が求められてい
た。In this detection method, if the expected cloud point is not properly input, it causes an error and cannot be used for an unknown sample. It is necessary to input the correct sensitivity for the oil type. Therefore, there is a need for a method of detecting a true value.
【０００８】[0008]
【表１】 また、上記従来の自動試験法とは別に光電式検出器を用
いる石油製品の自動曇り点の検出方法が提案されている
（特開昭６１−１７３１４０）。この検出方法は、試料
の外部から投光器より光が試料中に照射され、試料容器
底部からの反射光が受光器に入るもので、石油製品の曇
りが生じると受光器に入る光量が変わり検出される。し
かし、この方法では試料容器底部に生じる曇りの他、試
料の全体的な濁りなどでも光量が変化するので誤検出の
もととなる。[Table 1] In addition to the conventional automatic test method described above, a method for detecting an automatic cloud point of petroleum products using a photoelectric detector has been proposed (Japanese Patent Laid-Open No. 61-173140). In this detection method, the sample is illuminated with light from the outside of the sample, and the reflected light from the bottom of the sample container enters the light receiver.When the petroleum product becomes cloudy, the amount of light entering the light receiver changes and is detected. It However, in this method, the amount of light changes due to the entire cloudiness of the sample as well as the cloudiness that occurs at the bottom of the sample container, which causes erroneous detection.
【０００９】[0009]
【発明が解決しようとする課題】本発明は、前記従来方
法による問題点を解決するためになされたもので、光電
式検出器を用いて油の種類、組成、水分の有無を問わず
精度の良い石油製品の自動曇り点を検出する方法を提供
することを目的とする。SUMMARY OF THE INVENTION The present invention has been made in order to solve the problems of the above-mentioned conventional method, and uses a photoelectric detector to achieve high accuracy regardless of the type, composition, and presence or absence of oil. The aim is to provide a method for detecting the automatic cloud point of good petroleum products.
【００１０】[0010]
【課題を解決するための手段】本発明者らは、鋭意研究
した結果、特定の構造の光電式検出器および特定の検出
方法により、目的を達成することができた。As a result of intensive studies, the present inventors were able to achieve the object by a photoelectric detector having a specific structure and a specific detection method.
【００１１】すなわち、本発明は測温体および試料容器
の底部に所定の間隔で相対するように設けた一対の投光
器と受光器からなる光電式検出器を設置した自動曇り点
試験器の試料容器に試料を注入し、該試料の温度を降下
させて受光器に入る光量変化が、急激な変化開始温度Ｔ
ａ℃とそれより１℃低い（Ｔａ−１）℃の間で４ｍｖ以
上となる（Ｔａ−１）℃を曇り点とすることを特徴とす
る石油製品の自動曇り点検出方法である。That is, the present invention is a sample container for an automatic cloud point tester in which a photoelectric detector consisting of a pair of a projector and a light receiver, which are provided so as to face each other at a predetermined interval, are provided at the bottom of the temperature sensing element and the sample container. The sample is injected into the chamber, the temperature of the sample is lowered, and the change in the amount of light entering the photodetector causes a rapid change start temperature T
An automatic cloud point detection method for petroleum products, characterized in that the cloud point is (Ta-1) ° C, which is 4 mv or more between a ° C and (Ta-1) ° C which is 1 ° C lower than that.
【００１２】図１は、本発明方法による石油製品の自動
曇り点を検出する試験器システムの構成を示す。FIG. 1 shows the construction of a tester system for detecting the automatic cloud point of petroleum products according to the method of the present invention.
【００１３】測定用光電センサー１および測定用白金測
温体２を垂直にセットした試料容器３が試験槽５内に装
備されている。この試験槽には、冷却槽１０において冷
却された冷媒アルコールがポンプ８により循環されて槽
内温度が所定温度に保たれる。構内液面は液面検出用セ
ンサー１１により一定に保たれる。冷却槽１０は金属ジ
ュワー瓶からなり、温度調節用測温体９と冷凍機ユニッ
ト１２によって槽内アルコールが所定温度に冷却され
る。A test container 5 is equipped with a sample container 3 in which a measuring photoelectric sensor 1 and a measuring platinum temperature measuring element 2 are set vertically. In this test tank, the refrigerant alcohol cooled in the cooling tank 10 is circulated by the pump 8 to keep the temperature inside the tank at a predetermined temperature. The liquid level in the premises is kept constant by the liquid level detection sensor 11. The cooling tank 10 is composed of a metal dewar, and the alcohol in the tank is cooled to a predetermined temperature by the temperature control temperature measuring element 9 and the refrigerator unit 12.
【００１４】試験槽５内には温度調節用白金測温体４が
挿入されており、温度コントロール用電磁弁７を介して
冷媒アルコールの流量をコントロールして槽内温度が調
節される。また、ヒーター６が備えられており、槽内温
度を上昇させるために使用される。試験槽５及び試料容
器３内の温度条件は、ＪＩＳ Ｋ−２２６９に規定され
ている曇り点測定条件を満足するように設定、調節可能
である。A platinum temperature measuring element 4 for temperature adjustment is inserted in the test tank 5, and the temperature in the tank is adjusted by controlling the flow rate of the refrigerant alcohol through the temperature control solenoid valve 7. In addition, a heater 6 is provided and is used to raise the temperature in the bath. The temperature conditions in the test tank 5 and the sample container 3 can be set and adjusted so as to satisfy the cloud point measurement conditions specified in JIS K-2269.
【００１５】図２に本発明方法に使用する測定用光電セ
ンサーの構成を示す。本センサーは投光器１３及び受光
器１４と白金測温体２からなり、リード線１５により温
度出力と曇り点出力（ｍｖ）を不図示の記録計に接続
し、温度と、光量（ｍｖ）の変化曲線を画かせる。本セ
ンサーを図１の試料容器３にセットして使用するが、投
光器１３及び受光器１４は図に示す如く試料容器の底部
において所定の間隔で相対するように設けられ、測温体
２はその相対する投光器と受光器の中心に位置するよう
設置されている。投光器、受光器及び測温体を試料容器
の底部においてこのような関係位置に設置する理由は、
試料油の冷却によって曇りが生じはじめる（ワックスな
どが析出しはじめる）のは容器底部からであり、この曇
りの生じた温度を曇り点とするＪＩＳ規格試験法に準じ
たものである。図２において（Ａ）は曇りのない場合、
（Ｂ）は曇りの生じた場合の試料容器底部の状況を示し
ている。さらに、投光器と受光器が試料容器の底部で相
対することにより、試料中の微量水分などによる試料全
体を覆う曇り（濁り）などによる影響が避けられ、誤検
出のない正確な曇り点を検出することができる。FIG. 2 shows the structure of the measuring photoelectric sensor used in the method of the present invention. This sensor is composed of a projector 13 and a photodetector 14 and a platinum temperature measuring element 2. A lead wire 15 connects the temperature output and cloud point output (mv) to a recorder (not shown) to change the temperature and the light amount (mv). Draw a curve. This sensor is used by setting it in the sample container 3 of FIG. 1, but the light projector 13 and the light receiver 14 are provided so as to face each other at a predetermined interval at the bottom of the sample container as shown in the figure, and the temperature sensing element 2 is It is installed so as to be located at the center of the opposing projector and receiver. The reason why the sender, the receiver, and the temperature sensing element are installed at such a relative position on the bottom of the sample container is as follows.
It is from the bottom of the container that clouding begins (deposition of wax and the like) due to cooling of the sample oil according to the JIS standard test method in which the clouding temperature is the temperature at which this clouding occurs. In FIG. 2, when (A) is not cloudy,
(B) shows the condition of the bottom of the sample container when fogging occurs. Furthermore, since the light transmitter and the light receiver face each other at the bottom of the sample container, the influence of fogging (turbidity) that covers the entire sample due to a small amount of water in the sample can be avoided, and an accurate cloud point without false detection can be detected. be able to.
【００１６】次に本発明の試験器システムによる曇り点
の検出方法について述べる。Next, a method of detecting a cloud point by the tester system of the present invention will be described.
【００１７】ＪＩＳ規格の手順に則り、試料の予期曇り
点を設定してその温度より１４℃以上高い温度に調節し
た試料を試料容器に注入する（あるいは試料注入後該温
度に調節する）。この試料を図１の冷却システムにより
冷却を開始し、試料温度を徐々に降下させる。記録計に
記録されるその状況を図３の温度線にて示す。試料温度
が降下しても試料が透明である限り、投光器と受光器の
間の光量（ｍｖで表わされる）は図３の光量線に示され
る如く、殆ど変化しないか又は徐々に変化するのみであ
る。この徐々に降下しはじめる点を図３のＡ点に示す。
さらに冷却を続けて、ある点（Ａ1 点）において測定光
量の急激な降下がはじまる光量線の屈曲点をＡ1 点とす
ると、この点が試料中のパラフィンワックスが析出ある
いは分離し始める温度Ｔａ℃で、析出あるいは分離ワッ
クスによる曇りによって、投光器と受光器間の光量 が
急速に減少するのである。さらに冷却を続けるとワック
スの析出又は分離が進み、測定光量の急減が続くが、Ａ
3 点で光量は一定となりもはや変化しない。多くの試験
結果から、光量線の屈曲点Ａ1点における温度Ｔａ℃か
ら１℃の温度降下当り光量が４ｍＶ以上の低下が見られ
る場合の試料温度（Ｔａ−１）℃を曇り点としてよいこ
とがわかった。図３のＡ2 点がこれに相当する。このよ
うに本発明方法では、試料の冷却線と光量線を記録計に
画かせることにより、光量線の屈曲点を利用して自動的
に正確かつ容易に石油製品の曇り点を検出することがで
きる。In accordance with the procedure of JIS standard, the expected cloud point of the sample is set and the sample adjusted to a temperature higher than that temperature by 14 ° C. or more is injected into the sample container (or the temperature is adjusted after the sample injection). Cooling of this sample is started by the cooling system of FIG. 1, and the sample temperature is gradually decreased. The situation recorded in the recorder is shown by the temperature line in FIG. As long as the sample temperature is lowered, as long as the sample is transparent, the amount of light (expressed in mv) between the sender and the receiver hardly changes or only gradually changes as shown by the light amount line in FIG. is there. The point where the gradual descent starts is shown as point A in FIG.
When cooling is further continued and the bending point of the light amount line at which a sharp drop in the measured light intensity starts at a certain point (A 1 point) is taken as A 1, the point is the temperature Ta at which the paraffin wax in the sample begins to precipitate or separate. At ℃, the amount of light between the sender and the receiver decreases rapidly due to precipitation or clouding due to separation wax. If the cooling is further continued, the precipitation or separation of the wax will proceed, and the measured light quantity will continue to decrease sharply.
The light intensity becomes constant at three points and does not change anymore. According to many test results, the sample temperature (Ta-1) ° C may be used as the cloud point when the light amount decreases by 4 mV or more per 1 ° C from the temperature Ta ° C at the bending point A 1 of the light amount line. I understood. The point A 2 in FIG. 3 corresponds to this. As described above, in the method of the present invention, the cloud point of the petroleum product can be detected automatically and accurately by utilizing the bending point of the light quantity line by causing the recorder to draw the cooling line and the light quantity line of the sample. it can.
【００１８】[0018]
【実施例】図２の光電センサーを試料容器にセットし、
図１の自動曇り点試験器システムに装備して、自動試験
器からリード線により温度出力、曇り点出力を記録計に
接続し、各油種別による曇り点を測定した。油種は軽質
軽油（ＬＧＯ）、製品軽油（ＤＧＯ）、重質軽油（ＨＧ
Ｏ）及び脱色Ａ重油（脱色ＦＯＡ）の４種について測定
した。[Example] The photoelectric sensor of FIG. 2 was set in a sample container,
The automatic cloud point tester system of FIG. 1 was equipped with, and the temperature output and cloud point output were connected to the recorder from the automatic tester by the lead wire, and the cloud point for each oil type was measured. The types of oil are light gas oil (LGO), product gas oil (DGO), and heavy gas oil (HG).
O) and decolorized A heavy oil (decolorized FOA).
【００１９】試験条件、結果を表２に示す。比較のため
に手動法で測定した曇り点を基準値として上欄に示し
た。試料Ｎｏ．１の軽質軽油については、前記表１で誤
検出の例となったＮｏ．３の試料を用いた。試料の冷却
開始温度を各油種とも２０℃とし、冷却による温度降下
と光量（ｍＶ）の変化を１℃毎に表の下欄に示した。表
にみられるとおり、温度が下がると光量もゆるやかに降
下し、各油種とも或温度で急激に光量の減少がみられ
た。この温度からさらに１℃降下する間に各試料の光量
は次のように急減した。 試料Ｎｏ． Ｎｏ．１ Ｎｏ．２ Ｎｏ．３ Ｎｏ．４ ｍＶ／℃ １４．９ ４．３ １１．２ １６．４ この時の各試料の温度（表中括弧で囲われた光量に対応
する温度）を各試料の曇り点とすると、表２上欄にみら
れるように、本発明方法による曇り点値と基準の手動曇
り点値とがよく一致する。すなわち油種にかかわらず検
出値は正確である。図４は、表２の温度と光量の関係を
再録したものであるが、光量が急減し始める屈曲点が明
瞭にわかる。この屈曲点を利用して上述の曇り点を図か
ら容易に求めることができる。Table 2 shows the test conditions and results. For comparison, the cloud point measured by the manual method is shown in the upper column as a reference value. Sample No. For the light diesel oil of No. 1, the No. Three samples were used. The cooling start temperature of the sample was set to 20 ° C. for each oil type, and the temperature drop due to cooling and the change in light intensity (mV) are shown in the lower column of the table for each 1 ° C. As can be seen from the table, the light intensity decreased gradually as the temperature decreased, and the light intensity decreased sharply at a certain temperature for each oil type. The light amount of each sample drastically decreased as follows while further decreasing by 1 ° C. from this temperature. Sample No. No. 1 No. 2 No. 3 No. 4 mV / ° C 14.9 4.3 11.2 16.4 The temperature of each sample at this time (the temperature corresponding to the amount of light enclosed in parentheses in the table) is the cloud point of each sample. As can be seen from the above, there is a good agreement between the cloud point value obtained by the method of the present invention and the reference manual cloud point value. That is, the detected value is accurate regardless of the oil type. FIG. 4 is a reprint of the relationship between the temperature and the light amount in Table 2, and the bending point at which the light amount starts to suddenly decrease can be clearly seen. By utilizing this bending point, the cloud point can be easily obtained from the figure.
【００２０】[0020]
【表２】 [Table 2]
【００２１】[0021]
【発明の効果】試料容器の底部に所定の間隔で相対する
ように設けた一対の投光器と受光器からなり、この中心
に測温体を設けた光電式検出器を設置した自動曇り点試
験器を用いることによって、油の種類、水分の有無など
に影響されることなく石油製品の曇り点を精度よく自動
検出することが可能となった。EFFECT OF THE INVENTION An automatic cloud point tester comprising a pair of light emitters and light receivers provided at the bottom of a sample container so as to be opposed to each other at a predetermined interval, and a photoelectric detector having a temperature measuring element at the center thereof is installed. By using, it became possible to detect the cloud point of petroleum products accurately and automatically without being affected by the type of oil and the presence or absence of water.
【図１】本発明方法による石油製品の自動曇り点を検出
する試験器システムを説明する概略図である。1 is a schematic diagram illustrating a tester system for detecting an automatic cloud point of a petroleum product according to the method of the present invention.
【図２】本発明方法に使用する光電センサーの構成を説
明する側面図である。 （Ａ）試料に曇りのない場合の状況 （Ｂ）試料に曇りの生じた場合の状況FIG. 2 is a side view illustrating the configuration of a photoelectric sensor used in the method of the present invention. (A) Situation when the sample is not fogged (B) Situation when the sample is fogged
【図３】試料の温度と光量の関係を説明するグラフであ
る。FIG. 3 is a graph illustrating the relationship between the temperature of a sample and the amount of light.
【図４】本発明の実施例を示す油種別の温度対光量の関
係を説明するグラフである。FIG. 4 is a graph illustrating the relationship between the temperature and the light amount of each oil type according to the embodiment of this invention.
１ 測定用光電センサー ２ 測定用白金測温体 ３ 試料容器 ４，９ 温度調節用白金測温体 ５ 試験槽 ６ ヒーター ７ 温度コントロール用電磁弁 ８ ポンプ １０ 冷却槽 １１ 液面検出用センサー １２ 冷却機ユニット １３ 投光器 １４ 受光器 １５ リード線 1 Photoelectric sensor for measurement 2 Platinum temperature sensor for measurement 3 Sample container 4, 9 Platinum temperature sensor for temperature control 5 Test tank 6 Heater 7 Temperature control solenoid valve 8 Pump 10 Cooling tank 11 Liquid level detection sensor 12 Cooler Unit 13 Emitter 14 Light receiver 15 Lead wire
Claims (1)
隔で相対するように設けた一対の投光器と受光器からな
る光電式検出器を設置した自動曇り点試験器の試料容器
に試料を注入し、該試料の温度を降下させて受光器に入
る光量変化が４ｍＶ／℃以上となる温度から曇り点を検
出することを特徴とする石油製品の自動曇り点検出方
法。1. A sample container of an automatic cloud point tester equipped with a photoelectric detector consisting of a pair of a projector and a light receiver, which are provided so as to face each other at a predetermined interval on the bottom of the temperature sensing element and the sample container. An automatic cloud point detection method for petroleum products, which comprises detecting the cloud point from a temperature at which the sample is injected and the temperature of the sample is lowered so that a change in the amount of light entering the light receiver is 4 mV / ° C or more.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP26863893A JPH07120387A (en) | 1993-10-27 | 1993-10-27 | Detection of clouding point by automatic tester |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP26863893A JPH07120387A (en) | 1993-10-27 | 1993-10-27 | Detection of clouding point by automatic tester |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| JPH07120387A true JPH07120387A (en) | 1995-05-12 |
Family
ID=17461337
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP26863893A Pending JPH07120387A (en) | 1993-10-27 | 1993-10-27 | Detection of clouding point by automatic tester |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPH07120387A (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2011141164A (en) * | 2010-01-06 | 2011-07-21 | Nippon Soken Inc | Device for judging properties of fuel |
-
1993
- 1993-10-27 JP JP26863893A patent/JPH07120387A/en active Pending
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2011141164A (en) * | 2010-01-06 | 2011-07-21 | Nippon Soken Inc | Device for judging properties of fuel |
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