Crude oil specific gravity

Material balance and properties of the main fractions resulting from primary and secondary fractionation of a 50/50 volume % mixture of Arabian Ligb and heavy crude oil (specific gravity d f = 0.875). 

An oil tanker has collided witli a freighter at sea. A rupture on tlie side of the tanker lias released 450,000 gallons of crude oil (specific gravity = 0.88) into a rough sea. Estimate the spill area of oil resulting from the accident. 

Example 4.1. Crude oil, specific gravity 60 F/60 F = 0.887, flows through the piping shown in Fig. 4.2. Pipe A is 2-in. (50-mm) Schedule 40, pipe B is 3-in. (75-mm) Schedule 40, and each of pipes C is l -in. (38-mm) Schedule 40. An equal quantity of liquid flows through each of the pipes C. The flow through pipe A is 30gal/min (6.65 m /h). Calculate (a) the mass flow rate in each pipe, (b) the average linear velocity in each pipe, and (c) the mass velocity in each pipe. 

Crude Oil API Gravity Specific Gravity Sulfur (wt%) Nitrogen (wt%)... 

Accurate determination of the gravity of crude oil is necessary for the conversion of measured volumes to volumes at the standard temperature of 15.56°C (60°F) (ASTM D1250, Petroleum Measurement Tables). Gravity is also a factor reflecting the quality of crude oils. API gravity is a special function of relative density (specific gravity) represented by the following ... 

In oil bearing formations, the presence of polar chemical functions of asphaltenes probably makes the rock wettable to hydrocarbons and limits their production. It also happens that during production, asphaltenes precipitate, blocking the tubing. The asphaltenes are partly responsible for the high viscosity and specific gravity of heavy crudes, leading to transport problems. 

Crude oil base Speclflc gravity of heavy gasoline cut, Specific gravity of residue (BP > 350°C)... 

Estimating the general nature of crude oils by measurement of two specific gravities. j... 

Specific gravity is important commercially because the crude oil price depends partly on this property. The specific gravity is expressed most often in degrees API (see Chapters 1 and 4). 

During loading and unloading of crude oil tankers, the specific gravity of the crude is measured to confirm it meets the specifications for the case where payment is made on a barrel basis, or when the volume is converted into weight if the transaction is based on a price per ton (Hayward et al., 1980). 

Generally, the crude oils are classed according to specific gravity in four main categories ... 

Table 8.1 gives the average specific gravities of some typical crude oils. 

Crude oil name Country of origin Specific gravity... 

It is worthwhile to mention that the distribution of naphthenic acids is not uniform in a crude oil since a maximum value is observed in the fractions distilled between 400 and 450°C and whose average specific gravity is 0.950 (Figure 8.2). 

The specific gravity ol the crude oil at C. = 0 S705 rotation a = -(- 15-1 relractiTe index at23 C. = lAtHl. The saponification number is 2 4, equal to (l 84 per cent, of ester as bornyl or gemoyl acetate. 

Specific gravity is used to calculate the mass of crude oils and its products. Usually, crude oils and their liquid products are first measured on a volume basis, then changed to the corresponding masses using the specific gravity. 

A correlation index is a useful criterion for indicating the crude class or type. The following relationship between the mid-hoiling point in Kelvin degrees (°K) and the specific gravity of a crude oil or a fraction yields the correlation index (Bureau of Mines Correlation index). 

A tank 100 ft in diameter and 20 ft tall is filled with crude oil to within 2 ft of the top of the tank. One accident scenario is that a 6-in-diameter line connected to the bottom of the tank might break loose from the tank, allowing crude oil to drain out. If a 30-min emergency response time is required to stop the leak, estimate the maximum amount of crude oil (in gallons) leaked. The tank is vented to the atmosphere, and the specific gravity of crude oil is 0.9. 

A relief device must be designed for a vessel to relieve 1800 gpm of crude oil liquid in the event that a discharge line is blocked. The MAWP is 250 psig, and a maximum backpressure of 50 psig is expected. The specific gravity of the oil is 0.928, and its viscosity is 0.004 kg/m s. 

---