test method may not apply to samples with ASTM color higher than cloud point, n—in petroleum products and biodiesel This standard does not. Download/Embed scientific diagram | ASTM-D Cloud Point Test Apparatus from publication: Cloud Point and Wax Deposition Measurement Techniques. In the petroleum industry, cloud point refers to the temperature below which wax in diesel or ASTM D, Standard Test Method of Cloud Point of Petroleum Products (Constant Cooling Rate Method) is an The D test method determines the cloud point in a shorter period of time than manual method D .
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In the petroleum industry, cloud point refers to the temperature below which wax in diesel or biowax in biodiesels forms a cloudy appearance.
ASTM D – 02 Standard Test Method for Cloud Point of Petroleum Products
The presence of solidified waxes thickens the oil and clogs fuel filters and injectors in engines. The wax also accumulates on cold surfaces producing, for example, pipeline or heat exchanger fouling and forms an emulsion with water. Therefore, cloud point indicates the tendency of the oil to plug filters or small orifices at cold operating temperatures.
An everyday example of cloud point can be seen in olive oil stored piint cold weather. In these conditions, olive oil begins to develop white, waxy clumps of solidified oil that sink to the bottom of the container. In crude or heavy oils, cloud point is synonymous with wax appearance temperature WAT and wax precipitation temperature WPT.
The cloud point of a nonionic surfactant or glycol solution is the temperature at which the mixture starts to phase-separate, and two phases appear, thus becoming aatm.
This behavior is characteristic of non-ionic surfactants containing polyoxyethylene chains, which exhibit reverse solubility versus temperature behavior in water and therefore “cloud out” at some point as the temperature is raised.
Glycols demonstrating this behavior are known as “cloud-point glycols” and are used as shale inhibitors. The cloud point is affected by salinitybeing generally lower in more saline fluids. The wax crystals typically first form at the lower circumferential wall with the appearance of a whitish or milky cloud. The cloud point is the temperature just above where these crystals first appear.
The test poont is first poured into a test jar to a level approximately half full. A cork carrying the test thermometer is used to close the jar.
The thermometer bulb is positioned to rest at the bottom of the jar. The entire test subject is then placed in a constant temperature cooling bath on top of a gasket to prevent excessive cooling. Successively lower temperature cooling baths may be used depending on the cloud point. Lower temperature cooling bath must have temperature stability not less than 1.
It uses automatic apparatus and has been found to be equivalent to test method D The D test method determines the cloud point in a shorter period of time than manual method D Less operator time is required to run the test using this automatic method. Additionally, no external chiller bath or refrigeration unit is needed. Results are reported with a temperature resolution of 0. During this period, the sample is continuously illuminated by a light source.
An array of optical detectors continuously monitor the sample for the first appearance of a cloud of wax crystals. The temperature at which the first appearance of wax crystals is detected in the sample is determined to be the cloud point. From Wikipedia, the free encyclopedia. This article needs additional citations for verification.
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