Analysis of density factors in crude oil measurement

36.2003 Oil and gas storage and transportation

measuring technique

Analysis of density factors in crude oil measurement

Chen Wenying

(Huade Petrochemical Branch of Guangzhou Petrochemical General Factory)

Chen Wenying: Analysis of Density Factors in Crude Oil Measurement, Oil and Gas Storage and Transportation, 2003,22 (12) 36 ~ 38.

The density of crude oil is the most important value in crude oil measurement and plays a vital role in crude oil loss. The main factors affecting the density of crude oil are time, water content, clean water and sampling accuracy. This paper analyzes the causes of these factors, and puts forward some concrete measures to eliminate them.

Keywords:: analysis of factors of crude oil metering density

Density is an important value in crude oil measurement, which is very large for crude oil. After the crude oil in the oil tank is completely precipitated, the water contained in it will sink.

Loss plays a vital role. At present, the measured density of crude oil in China drops to the bottom of the tank to become a aquifer, and the water content of crude oil will decrease, and the density will also decrease.

Generally, GB 1884-92 densitometer method is used to measure the degree. Although it will be reduced. For example, the crude oil provided by the oil seller has high density and high water content.

Although the density measurement is not complicated and there are many problems to be paid attention to in operation, the density sampled and analyzed by the oil buyer is very small and the water content is trace.

For example, the height, diameter, temperature and flow trace of crude oil in the container. At this time, if the inspectors check the manifest, they will find that there are lights in the cabin.

Compared with oil loading, the bubbles generated during oil loading, the cleanliness and dryness of densitometer, and the volume of ambient water are obviously increased. Obviously, this is transportation.

Temperature changes, etc. All these affect the accuracy of crude oil density measurement, and the water in the oil slowly precipitates in this process. Just finished oiling, and it's all sunk.

Analyze the factors that affect the density of crude oil, and master the density and water content of crude oil measured after the road drop (usually about 8 hours) that may cause errors.

Diameter. And take effective measures to ensure that the meter of crude oil is very different, especially for crude oil with high viscosity and high water content.

The accuracy of. Oil. The influence of Mingshui on density is more prominent. Just finished losing oil, tank bottom

When the Mingshui layer rolls into the oil, the density of crude oil will inevitably increase, such as

First, the factors affecting the density of crude oil If the crude oil is left standing for 8 hours after transportation, the Mingshui layer will sink to the bottom of the tank again, and the crude oil will be dense.

The degree is correspondingly reduced. It can be seen that Mingshui and water content have great influence on the density of crude oil.

1, time has a great influence.

There are many light components in crude oil, so the density is small, and it is not as soon as possible after sampling.

The measurement shows that the density of crude oil will increase when the light components volatilize. The sampling position and accuracy of floating roof oil have great influence on the density of crude oil.

There is basically no gas space between the storage tank, floating roof and liquid level, and the crude oil breathing is damaged. When measuring crude oil, according to GB4756-84 Petroleum and Liquid Stones.

Less consumption, little change in crude oil density. But sometimes the weather temperature difference changes more than the manual sampling method of oil products, and it is taken at 1/6 below the liquid surface.

Large, measurement and sampling can't be done in the early morning or at night. Oil tank, the middle part of 1/2 and the lower part of 5/6 are mixed in equal volume. correct

The sealing effect can't reach 100%, so the escape of oil vapor is always greater than that of uneven crude oil, so this method can't be adopted. For two density stages

This is inevitable. The density of the same tank of oil will definitely change in a few days. The crude oil mixture with little difference can be 1/6, 1/2, 5/6, etc.

The variation value can even be increased by 0. 1%. Analyze the same mixed samples at different times. For the mixture of two oils with density difference greater than 3%

When sampling oil samples, if human error is excluded, the density is also different. Oil, sampling according to the following conditions.

2. Influence of water content and open water (1) The oil density at the bottom of the tank is small, and the discharged oil density is high.

For the same crude oil, the higher the water content, the higher its density. When the oil density at the bottom of the oil tank is less than 3% of the discharged oil density, it passes through