AUTOMATION OF GASOLINE PRODUCTION PROCESS

Hexane fraction and stable gasoline (pentane sum fraction) from finished product warehouse are supplied to SM-1/1,2 mixers. Flow of hexane fraction and stable gasoline (pentane sum fraction) is controlled by sensors F317, F316 (F318) and valves FV317.3, FV316.3 (FV318.3). The mixture of components then enters the E-1 tank. The total flow rate of the mixture (sensor FIQ 320) is measured before being fed into the E-1 tank.

Operating mode of E-1 tank is provided by sensors as follows:

- high (L411.1) and low (LIT 411.2) levels are recorded and signaled;

- temperature is measured and recorded (sensor T117).

Pentanized hexane fraction is taken from tank E-1 in specified ratio by pumps H-1/1,2,3 and supplied to mixers SM-3/1,2. The pentanized hexane fraction flow rate is controlled (F319 sensor) by valve FV319.3 which is installed on the N-1/1,2,3 pump discharge line.

Safe operation of N-1/1,2,3 pumps is provided by automatic interlocks with shutdown of operating pump:

- in case of emergency pressure drop between pump discharge and discharge (PD228 sensor);

- in case of emergency level drop in the pump (L412 sensor).

The high octane toluene component from the finished product storage is supplied to tank E-2. The operating mode of the E-2 tank is provided by the sensors as follows:

- high (L414.1) and low (L414.2) levels are recorded and signaled;

- temperature is measured and recorded (sensor T119).

Toluene is taken from E-2 tank by H-2/1 pump and fed to SM-2/1,2 mixers. Toluene flow rate is controlled (F321 sensor) by valve FV321.3 which is installed on the N-2/1 pump discharge line.

Safe operation of N-2/1,2,3 pumps is provided by automatic interlocks with shutdown of operating pump:

- in case of emergency pressure drop between pump discharge and discharge (sensor PD238.1);

- in case of emergency level drop in the pump (sensor L415.1).

The high-octane MTBE component from the finished product warehouse is supplied to tank E-3. Operating mode of E-3 tank is provided by sensors as follows:

- high (L416.1 sensor) and low (L416.2 sensor) levels are recorded and signaled;

- temperature is measured and recorded (T120 sensor).

From E-3 tank MTBE is taken by N-2/3 pump and supplied to SM-2/1,2 mixers. The MTBE flow rate is controlled (sensor F322) by valve FV322.3, which is installed on the N-2/3 pump discharge line. In case of failure of N-2/1 or N-2/3 pump operation the standby N-2/2 pump operates.

Extraline from the fuel and lubricants warehouse is supplied to tank E-4. Operating mode of E-4 tank is provided by sensors as follows:

- high (L418.1) and low (L418.2) levels are recorded and signaled;

- temperature is measured and recorded (sensor T122).

Extraline is taken from tank E-4 in the specified ratio by pump N-3/1.2 and supplied to delivery pipeline of pumps N-2/1.2. The total extraline flow rate (F325 sensor) is measured and recorded on the N-3/1,2 pump discharge line.

Safe operation of the N-3/1,2 working pumps is provided by automatic interlocks with shutdown of the working pump in case of emergency reduction of the pressure drop between the discharge and discharge of the pump (PD245 sensor).

Toluene, MTBE and extraline are mixed in the SM-1/1,2 mixer and mixed with the pentanized hexane fraction into the SM-3/1,2 mixer. The hydrocarbon stream then enters the E-5/1,2 or E-6/1,2 tank. Operating mode of E-5/1,2 vessels is provided by sensors as follows:

- high (L421.1, L422.1) and low (L421.2, L422.2) levels are recorded and signaled;

- Temperature is measured and recorded (sensor THAS 1, THAS 2).

When the level in the E-5/1 2400 mm tank is reached, the shut-off valve PV607 (on the product supply line to the E-5/1) is automatically closed and the shut-off valve PV612 (on the product supply line to the E-5/2) is opened. When the shut-off valve PV607 is closed, the shut-off valve PV609 (on the product line from E-5/1) is automatically opened and the pump N-4/1 (N-4/2) is switched on.

When the level in the E-5/2 2400 mm tank is reached, the shut-off valve PV612 (on the product supply line to the E-5/2) is automatically closed and the shut-off valve PV613 (on the product supply line to the E-6/1) is opened. When the shut-off valve PV612 is closed, the shut-off valve PV610 (on the product line from E-6/1) is automatically opened and the pump N-4/1 (N-4/2) is switched on.

When the level in the E-6/1 2400 mm tank is reached, the shut-off valve PV613 (on the product supply line to E-6/1) is automatically closed and the shut-off valve PV618 (on the product supply line to E-6/2) is opened. When the shut-off valve PV613 is closed, the shut-off valve PV616 (on the product line from E-6/1) is automatically opened and the pump N-4/3 (N-4/2) is switched on.

When the level in the E-6/2 2400 mm tank is reached, the shut-off valve PV618 (on the product supply line to E-6/2) is automatically closed and the shut-off valve PV607 (on the product supply line to E-5/1) is opened. When the shut-off valve PV618 is closed, the shut-off valve PV619 (on the product line from E-6/2) is automatically opened and the pump N-4/3 (N-4/2) is switched on.

After the circulation is completed, a sample of gasoline is taken and its octane number is determined according to the research method at the UIT-85 unit. If this indicator is not lower than 80 points, then the circulation is stopped and gasoline is sent to tank E-7, where a sample of gasoline is taken and analytical control is carried out for all indicators. The high (L429.1) and low (L429.2) levels are recorded and signaled in tank E-7.

If the analysis on UIT-85 does not give the necessary octane index (i.e. below 80 points according to the research method), then additional addition of an antidetonator or a mixture of components is required. At the same time, the mixture is simultaneously circulated according to the tank-pump scheme. Further, sampling is carried out, analysis for UIT-85 and after bringing to the required octane the product is pumped to E-7.

Atmospheric sediments from the pallet of the filling point site (waste water) are supplied by gravity to the underground tank E-8 of the gasoline production plant, from where, together with the wastewater of the plant, nitrogen is transferred to the industrial effluent network for purification. Level rise and drop (L429) is signaled in waste water tank E-8.