SU988320A1 - Gas condensate stabilization method - Google Patents

Description

(54) METHOD FOR STABILIZING GAS CONDENSATE

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The invention relates to the processing of unstable condensate and can be used for its stabilization in the gas industry.

There is a method of stabilizing gas condensate, which consists in the sequential decompression and separation of raw materials 1.

The disadvantage of this method is large losses of propane and butane with stabilization gases that do not meet the requirements of the existing standards. Further transportation of these gases is impossible without their multistage dozhat. Therefore, stabilization gases are usually combusted.

The closest to the proposed method is the stabilization of gas condensate, including the separation of the feedstock in a separator under a pressure of 18-22 kg / cm2, deethanization in an absorption steam column (AFL) with a portion of the liquid from the separator for irrigation, and the rest after heating to 120 150 ° C as feed in the middle of the column and stabilization of the de-ethanized condensate in the distillation column. The steam flow is generated by a firing furnace. The top product of the AOK is

The methane-ethane fraction, which is usually combined with the separation gas and after compression, is directed to the main gas pipeline, and the bottom product of the KLA is de-ethanized condensate supplied for stabilization to the distillation column 2.

The disadvantage of this method is high energy consumption, which is associated with a high fuel consumption in fire, Q chi and the cost of the subsequent compression of de-ethanized gases. In addition, the stable condensate leaving the plant has a high temperature (170-180 ° C) and its further cooling is carried out in air coolers, also

15 are very energy intensive.

The purpose of the invention is to reduce the energy intensity of the process by reducing the heat load.

This goal is achieved by the fact that in the method of stabilizing gas condensate, which includes separating the raw material in the separator, de-ethanizing in the absorption and stripping column with feeding part of the liquid from the separator to irrigation, and the rest as feeding in the middle of the column, and stabilizing the de-ethanized condensate in column, the gas stream separator is heated to the temperature of the cube of the absorption and Stripping columns and served in its lower part.

The drawing shows an installation in which the proposed method is implemented.

The initial unstable condensate expands in throttle 1 to a pressure of about 20-30 atm and enters separator 2, where it is partially degassed. The separator liquid is divided into two parts: one is fed to the top plate of the AOK 3 as cold irrigation, and the other, after being heated in a recuperative heat exchanger 4 with stable condensate (bottom product of distillation column 5) to 120-140 ° C, is sent as power to the middle part of the AOK 3. The gas of the separator 2 is heated with stable condensate in the recuperative heat exchanger 6 up to the bottom temperature of the column 3 and is directed to its lower plate for combined exposure. The AOK is equipped with a firing furnace 7, all of which is a boiling point, its boiling function.

From the top of the column 3, the methane-ethane fraction is withdrawn, and from below, the de-ethanized condensate, which, after expansion in the choke 8 to a pressure of 10-16 atm, is sent to the middle part of the distillation column 3. The products of this co-fraction are the liquid propane-butane fraction (top product) and stable condensate, giving off its heat in heat exchangers 4 and 6. Column 5 is equipped with a condenser 9 and a firing furnace 10.

An example illustrating the effectiveness of the proposed method of stabilizing gas condensate. A mixture of the composition shown in Table 1 is fed to the separation.

Pressure in AOK 3 - 20 at, in column 5 - 15 at. The number of plates in both columns is 40. The separation temperature (temperature of cold irrigation) is 15 ° C. The power is supplied to the 14th plate (top) AOK 3 at 140 ° C. The gas composition of the separator 2 is given in Table 2. When the plant is operated in the mode of a known method, the heat load on the AOK boiler 3 is 12,125,000 kcal / h. The gas of separator 2 is heated with stable condensate up to 170 ° C and fed to the 40th plate of AOK 3 to obtain de-ethanized condensate of the same composition. Heat is supplied to the AOK 3 boiler in the amount of 9,100,000 kcal / h, i.e., 25% rel. less than in the known method. Obviously, this reduction in energy consumption is achieved not only by recovering some of the heat from the stable condensate, but also by increasing the relative volatility of the key components associated with a decrease in the partial pressure of propane.

The use of the proposed method allows a 10–15% reduction in energy costs for the compression of de-ethanization gases, since it can also carry out the process at a higher pressure.

Table 1

The composition of the total liquid nutrition absorption-Stripping column

4606,131,00000

Table 2 The composition of the gas separator

Claims (1)

Claim The method of stabilization of gas condensate, including the separation of the feedstock in the separator, deethanization in an absorption 5-stripping column with a portion of the liquid from the separator to irrigate it, and the rest as power in the middle of the column and stabilization of the deethanized condensate in the distillation column, characterized in that, with the aim of ¹⁰ reducing the energy intensity of the process by reducing the heat load, the gas stream of the separator is heated to the temperature of the cube of the absorption-stripping column and fed to its lower part.