13

2018

-

04

Common flow chart of 21 chemical plants

Author:


This article covers the flowchart:

Flow chart of isomerization device

Flow chart of benzene extraction device

Flow chart of diesel hydrogenation reaction part

Flow chart of diesel hydrofractionation part

Flow diagram of the hydrogenation reaction part of the aviation coal

Flow chart of hydrofractionation part of aviation coal

Flow chart of hydrogen production unit

Schematic diagram of the process of hydrogen and steam production

Sulfur recovery sulfur production part flow chart

Flow chart of sulfur recovery exhaust gas part

Flow chart of solvent regeneration device

Acid water stripping plant process

Flow chart of the reaction part of the PP device

Flow chart of flash and steam steaming part of PP device

Flow chart of granulation part of PP plant

Flow chart of storage and transportation system device, tank farm oil system pipeline flushing principle

Flow chart of storage, transportation and venting system

Air separation system flow chart

Chemical water flow diagram

Flow chart of circulating water field

Flow chart of saline sewage treatment

Flow chart of oily wastewater treatment

1. Flow chart of isomerization device


The isomerization plant is similar to a normal hydrorefining unit.


Taking butane isomerization as an example (see figure), the butane feed is separated from isobutane by a deisobutane column, and the bottom of the column is mainly n-butane, which is mixed with hydrogen and heated into the reactor. The reaction pressure is about 2.1~2.8MPa, the temperature is 145~205 °C, the molar ratio of hydrogen and hydrocarbons is 0.1~0.5, and the airspeed is 3~5h-1.
 


 

The reaction product is separated from hydrogen by the separator (recycled), and then a small amount of pyrolysis gas (used as fuel gas) is separated by the stabilization column and then de-isobutane tower. The n-butane cycle at the bottom of the column is reactioned, and the yield of isobutane can reach more than 90%.
 

When isobutane is fed as an alkylation supplement, the unit can be combined with an alkylation unit into a unit, which saves equipment and investment.
 

2. Flow chart of benzene extraction device
 


As a device for extracting benzene contained in reformed gasoline, the benzene extraction device mainly includes the following parts: pre-fractionation, extraction distillation, solvent recovery and regeneration, benzene refining and C6 non-aromatic hydrocarbon hydrogenation reaction, fractionation.


3. Flow chart of diesel hydrogenation reaction part
 


Under the control of the liquid level and flow of the raw oil buffer tank, the raw oil from the raw oil filter removes particles larger than 25 microns in the raw material after being removed from the raw oil filter, and enters the raw oil buffer tank, and the raw material oil buffer tank is sealed with fuel gas.


After the raw oil from the raw oil buffer tank is pressurized by the hydrogenation feed pump, under flow control, it is exchanged by the reaction effluent/raw material oil heat exchanger, mixed with mixed hydrogen into the reaction effluent/reaction feed heat exchanger, and then heated to the temperature required for the reaction by the reaction feed heating furnace and enters the hydrorefining reactor. The reactor is equipped with two catalyst beds with quenching hydrogen injection facilities between the beds.


The reaction effluent from the hydrorefining reactor is cooled to 45 °C by the reaction effluent/reaction feed heat exchanger, reaction effluent/low oil heat exchanger, reaction effluent/raw material oil heat exchanger in turn with the reaction feed, low oil separation and raw material oil, and then cooled to 45 °C by the reaction effluent air cooler and water cooler, and enters the high-pressure separator. In order to prevent the precipitation of ammonium salts in the reaction effluent at the low temperature, the deaerated water is injected into the pipeline on the upstream side of the reaction effluent air cooler by a water injection pump.


The cooled reaction effluent is separated in a high-pressure separator with oil, gas and water. After the high separation gas (circulating hydrogen) is discharged by the inlet separating tank of the circulating hydrogen compressor, it enters the circulating hydrogen compressor for boosting, and then divides into two ways: one way as quenching hydrogen into the reactor; All the way it is mixed with new hydrogen from the new hydrogen compressor, and the mixed hydrogen is mixed with the raw oil as a reaction feed. Sulfur-containing and ammonia-containing wastewater is discharged from the bottom of the high-pressure separator to the acid water stripping device for treatment. The high-content oil phase enters the low-pressure separator through a pressure reducing control valve under level control, and its flash gas is discharged to the plant's fuel gas network.


The low-separation oil enters the diesel stripper after being exchanged with refined diesel and low-oil heat exchanger and reactive effluent/low-oil heat exchanger with refined diesel and reaction effluent respectively. The incoming column temperature is controlled by a bypass adjustment of the reaction effluent/low oil separator. The new hydrogen enters the new hydrogen compressor after being separated by the inlet dispensing tank of the new hydrogen compressor, and is mixed with circulating hydrogen after two stages of boosting.


4. Flow chart of diesel hydrofractionation part
 


The low-separation oil from the reaction part enters the diesel stripper through the refined diesel/low-oil heat exchanger, reaction effluent/low-oil heat exchanger to about 275 °C.


The bottom of the tower is stripped with 1.0MPa superheated steam, and the oil and gas at the top of the tower are condensed and cooled to 40°C by the top air cooler of the stripper and the top aftercooler of the stripper, and enter the top return tank of the stripper tower for the three-phase separation of gas, oil and water. The flash gas is discharged to the catalytic unit. After the oil phase is boosted by the stripper top return pump, part of it is used as the top return flow of the tower, and part is used as the crude gasoline decatalytic device. Sulfur-containing ammonia-containing wastewater is sent out of the device together with high-content sewage.


In order to inhibit the corrosion of hydrogen sulfide on the top pipeline and cold exchange equipment, the injection of corrosion inhibitor measures is adopted in the top pipeline of the tower. The corrosion inhibitor self-inhibitor tank is injected into the top pipe of the tower by the corrosion inhibitor pump.


The refined diesel fuel at the bottom of the tower is pressurized by the diesel pump and exchanged with low oil to about 80 °C, and then cooled to 50 °C after entering the diesel air cooler.


5. Flow chart of aviation coal hydrogenation reaction part
 


6. Flow chart of hydrofractionation part of aviation coal
 


7. Flow chart of hydrogen production device
 


8. Simplified diagram of the flow of hydrogen and steam production
 


9. Flow chart of sulfur recovery and sulfur production
 


10. Flow chart of sulfur recovery exhaust gas
 


11. Flow chart of solvent regeneration device
 


12. Acid water stripping device process
 


13. Flow chart of the reaction part of the PP device
 


PP plant in the petrochemical industry, refers to polypropylene production equipment, mainly used to polymerize propylene to produce polypropylene equipment.


The reaction part includes the first polymerization reaction unit and the second polymerization reaction unit.


The first polymerization reaction unit refers to the horizontal stirred bed reactor under a certain temperature and pressure, with propylene as the main raw material, hydrogen as the relative molecular weight regulator, under the action of the catalyst system, by gas-phase reaction polymerization to generate polypropylene powder.


The setting and control method of the second polymerization reaction unit is basically the same as that of the first polymerization reaction unit, the purpose is to improve the utilization efficiency of the catalyst, and at the same time, using the tandem characteristics of the second polymerization reaction unit and the first polymerization reaction unit, ethylene is added to produce impact copolymers.


14. Flow chart of flash steaming and steam steaming part of PP device
 


15. Flow chart of granulation part of PP plant
 


Polypropylene resin is mixed with different types of additives, heated at high temperature (200-300 °C) to reach a molten state, and underwater granulation is carried out through the template under the action of twin screw extruder and molten gear pump.


The main purposes of granulation are:


Add various additives to improve product performance;


Easy to package and transport products;


Improve product quality.


16. Flow chart of pipeline flushing principle of storage and transportation system device and tank farm oil system
 


17. Flow chart of storage, transportation and venting system
 


18. Air separation system flow chart
 


Air separation unit is a set of industrial equipment used to separate the components of the air and produce oxygen and nitrogen.


Generally speaking, air separation unit refers to the separation device of various air components in a chemical plant. Specifically, gases such as nitrogen, oxygen, argon and some other gases are separated from the air.


19. Chemical water flow chart
 


20. Flow chart of circulating water field
 


The circulating water is output after pressurization by the circulating water pump, most of which is exchanged in the water workshop for heat exchange, and the return water of heat exchange enters the pool after cooling down through the cool water tower, and part of it returns to the pool after being filtered by the valveless filter. When the circulating water index is close to the high limit, turn on the sewage pump for replacement, and replenish water to the circulating pool at the same time.


21. Flow chart of saline sewage treatment
 


22. Flow chart of oily sewage treatment
 

 
 
 

Device, flow chart, reaction, partial, effluent, ingress, feedstock oil, oil separation, diesel