Design and construction of gas condensate distillation unit
1.Introduction
Pishgam Palayesh Force Company is a designer and manufacturer of gas condensate and petrochemical distillation units that have been implemented in various projects such as: Kuwait-Iraq, Damascus-Syria, Aleppo-Syria, Yazd-Iran-Sadr Gostar Shimi and Qom-Iran-Petroaspashid,... and is currently being implemented on the Satrap Topping project located in Mehr Industrial Park - Parsian Special Economic Zone.
Gas condensate distillation units process gas condensates. These units separate hydrocarbon mixtures into different parts based on boiling points and enable the recovery of valuable products such as LPG, naphtha and heavier hydrocarbons.
2.Design Components
A typical gas condensate distillation unit consists of several key components:
Distillation Tower: The central element where the separation occurs. It facilitates the contact between rising vapor and descending liquid, allowing for mass transfer and fractionation.
Reboiler: Heats the bottom of the distillation column, providing vapor to drive the separation process.
Condenser: Cools the overhead vapor from the distillation tower, converting it back into liquid form.
Auxiliary Equipment: Includes pumps, heat exchangers, and control systems that support the operation of the main components.
The distillation unit (atmospheric and vacuum) is the first refining unit and one of the most important refinery units, separating the incoming raw feed into different oil cuts. The products of the distillation unit are mainly considered mid-range products in the refining industry. In many cases, increasing the quantity or quality of a specific cut using operating parameters and without changing the design and size of the various equipment of the unit is intended, in which case the existence of an accurate simulation file is of particular importance.
After simulating the distillation unit process, the created file can be used as a suitable tool for studying and optimizing them, in order to determine the optimal process conditions in order to increase the unit's profit, considering the desired product specifications, changing process parameters, and defining different scenarios. The distillation unit performance index is studied both at the refinery level and at the unit and equipment level, as well as general indicators such as water consumption, steam consumption, electricity consumption, and the ratio of light to heavy products.
3. System modeling
Simulation and optimization of the crude oil distillation unit is carried out with the aim of optimizing performance and reducing costs.
– Definition of inputs and outputs: First, the process inputs such as the type and composition of crude oil, temperature, pressure, and also the expected outputs (various products such as gasoline, gas oil, etc.) are defined.
, The distillation unit model is designed using elements such as distillation tower, tanks, pumps, Aspen HYSYS: It is designed using Aspen HYSYS software and heat exchangers.
3.1. Process simulation
– Adding various equipment: Simulation of all equipment and processes in the distillation unit is carried out along with their operating parameters (temperature, pressure, flow rate).
– Setting operating conditions: Operating conditions and determination of physical and chemical characteristics of fluids are carried out with maximum accuracy to create a reliable model.
– Obtaining internal flows: After simulation, various flows, temperatures and pressures at different points in the system are calculated and analyzed.
4. Process Flow
4.1. The process typically involves several stages:
Feed Preparation: The gas condensate is preheated and often dehydrated to remove water before entering the distillation unit. This step is crucial for efficient separation.
Flash Separation: Initial separation occurs in a flash vessel where lighter components are removed under reduced pressure.
Distillation: The feed enters the distillation tower where it is heated by the reboiler. As it rises through the column, lighter fractions vaporize and move upwards while heavier fractions descend.
Product Recovery: The overhead products are condensed and collected, while bottom products are removed for further processing or storage.
5. Operational Considerations
5.1. Temperature and Pressure Management:
The operating pressure in a gas condensate distillation unit is typically maintained around 10 to 30 bara, depending on the desired product specifications.
Temperature control is critical; reboilers often operate at around 190 °C to ensure effective separation of components based on their boiling points.
6. Efficiency Enhancements:
To optimize performance, several strategies may be employed:
Heat Integration: Utilizing heat exchangers to recover energy from various streams can significantly reduce operational costs.
Column Design Variations: Different configurations (e.g., tray vs. packed columns) can be analyzed to improve separation efficiency while minimizing capital costs.
Reflux Management: Adjusting reflux ratios can enhance product purity and yield by allowing better contact between vapor and liquid phases within the column45.
The overall process of simulation and optimization of the ongoing Topping Satrap project unit is shown below:

Pishgam Palayesh Force Company is a designer and manufacturer of gas condensate and petrochemical distillation units that have been implemented in various projects such as: Kuwait-Iraq, Damascus-Syria, Aleppo-Syria, Yazd-Iran-Sadr Gostar Shimi and Qom-Iran-Petroaspashid,... and is currently being implemented on the Satrap Topping project located in Mehr Industrial Park - Parsian Special Economic Zone.
Gas condensate distillation units process gas condensates. These units separate hydrocarbon mixtures into different parts based on boiling points and enable the recovery of valuable products such as LPG, naphtha and heavier hydrocarbons.
2.Design Components
A typical gas condensate distillation unit consists of several key components:
Distillation Tower: The central element where the separation occurs. It facilitates the contact between rising vapor and descending liquid, allowing for mass transfer and fractionation.
Reboiler: Heats the bottom of the distillation column, providing vapor to drive the separation process.
Condenser: Cools the overhead vapor from the distillation tower, converting it back into liquid form.
Auxiliary Equipment: Includes pumps, heat exchangers, and control systems that support the operation of the main components.
The distillation unit (atmospheric and vacuum) is the first refining unit and one of the most important refinery units, separating the incoming raw feed into different oil cuts. The products of the distillation unit are mainly considered mid-range products in the refining industry. In many cases, increasing the quantity or quality of a specific cut using operating parameters and without changing the design and size of the various equipment of the unit is intended, in which case the existence of an accurate simulation file is of particular importance.
After simulating the distillation unit process, the created file can be used as a suitable tool for studying and optimizing them, in order to determine the optimal process conditions in order to increase the unit's profit, considering the desired product specifications, changing process parameters, and defining different scenarios. The distillation unit performance index is studied both at the refinery level and at the unit and equipment level, as well as general indicators such as water consumption, steam consumption, electricity consumption, and the ratio of light to heavy products.
3. System modeling
Simulation and optimization of the crude oil distillation unit is carried out with the aim of optimizing performance and reducing costs.
– Definition of inputs and outputs: First, the process inputs such as the type and composition of crude oil, temperature, pressure, and also the expected outputs (various products such as gasoline, gas oil, etc.) are defined.
, The distillation unit model is designed using elements such as distillation tower, tanks, pumps, Aspen HYSYS: It is designed using Aspen HYSYS software and heat exchangers.
3.1. Process simulation
– Adding various equipment: Simulation of all equipment and processes in the distillation unit is carried out along with their operating parameters (temperature, pressure, flow rate).
– Setting operating conditions: Operating conditions and determination of physical and chemical characteristics of fluids are carried out with maximum accuracy to create a reliable model.
– Obtaining internal flows: After simulation, various flows, temperatures and pressures at different points in the system are calculated and analyzed.
4. Process Flow
4.1. The process typically involves several stages:
Feed Preparation: The gas condensate is preheated and often dehydrated to remove water before entering the distillation unit. This step is crucial for efficient separation.
Flash Separation: Initial separation occurs in a flash vessel where lighter components are removed under reduced pressure.
Distillation: The feed enters the distillation tower where it is heated by the reboiler. As it rises through the column, lighter fractions vaporize and move upwards while heavier fractions descend.
Product Recovery: The overhead products are condensed and collected, while bottom products are removed for further processing or storage.
5. Operational Considerations
5.1. Temperature and Pressure Management:
The operating pressure in a gas condensate distillation unit is typically maintained around 10 to 30 bara, depending on the desired product specifications.
Temperature control is critical; reboilers often operate at around 190 °C to ensure effective separation of components based on their boiling points.
6. Efficiency Enhancements:
To optimize performance, several strategies may be employed:
Heat Integration: Utilizing heat exchangers to recover energy from various streams can significantly reduce operational costs.
Column Design Variations: Different configurations (e.g., tray vs. packed columns) can be analyzed to improve separation efficiency while minimizing capital costs.
Reflux Management: Adjusting reflux ratios can enhance product purity and yield by allowing better contact between vapor and liquid phases within the column45.
The overall process of simulation and optimization of the ongoing Topping Satrap project unit is shown below:
