Streamlining Operations: How PHEs are Improving Oil and Gas Processes

Heat exchangers are essential pieces of equipment in various industries, including space heating, refrigeration, air conditioning, power generation, chemical, petrochemical, natural gas processing, and sewage treatment. One industry that relies heavily on the utilization of heat exchangers is the petroleum refining industry. 

Crude oil is refined using fractional distillation to produce valuable petroleum products, and heat exchangers play a crucial role in ensuring that the feedstock reaches the required reaction temperatures. 

In this blog, we'll explore how Plate Heat Exchangers (PHEs) are revolutionizing the oil and gas industry, and the innovative solutions they offer to enhance productivity, efficiency, and sustainability. 

MAIN COMPONENTS/EQUIPMENTS OF CRUDE REFINING 

OIL INDUSTRY

 Desalters

 Atmospheric distillation tower

 Vacuum distillation tower

 Heat exchangers, coolers, and process heaters

 Tank storage

 Heater and boiler

 Gas and air compressor

 Turbines

 Pumps, piping and valves

There are a few steps in the crude oil treatment process:

1. Desalting

2. Atmospheric distillation

3. Distillation separation

4. Treatment of residual oils

5. Storage

6. Transportation

Desalting

Did you know that crude oil often contains water, inorganic salts, suspended solids, and water-soluble trace metals that can damage equipment and cause safety issues? That's why desalting, or the removal of these contaminants through dehydration, is a crucial step in the oil and gas industry. 

Desalters, which heat the crude oil to 100-150°C and mix it with fresh water, remove inorganic salts such as sodium chloride that can cause corrosion, plugging, and fouling of downstream process equipment. This process ensures the safe and efficient production of high-quality crude oil products.

Atmospheric Distillation/Crude Oil Distillation

To refine crude oil, atmospheric distillation is essential as it is the first and crucial step in the process. The process separates crude oil into distillation cuts for further processing and sets the capacity limit for the entire refinery. The heated crude oil is injected into the distillation column, and the hydrocarbons condense at different temperatures, leading to their separation into different distillation cuts. 

These cuts are then further processed or blended into finished products. The remaining crude oil is passed through a side stripper to separate kerosene, and the bottom stream is sent to the vacuum tower for further separation.

Crude Distillation Unit

Vacuum Distillation

Petroleum crude oil is a complicated mixture that includes several hundred hydrocarbon compounds, typically ranging from 3 to 60 carbon atoms per molecule. Refining this crude oil begins with atmospheric distillation at a pressure slightly above atmospheric. The temperature must not exceed 370 to 380 °C, as high molecular weight components can crack and form petroleum coke, which can clog the furnace, piping, and column.

The residual oil produced from the atmospheric distillation consists of hydrocarbons boiling above 370 to 380 °C. Vacuum distillation is used to further distill this residual oil at an absolute pressure as low as 10 to 40 mmHg, allowing for distilling heavier materials at lower temperatures than required at atmospheric pressure and avoiding thermal cracking.

The vacuum distillation process produces heavy distillates such as light and heavy gas oil, which can be refined into lube oil base stocks or feedstock for hydrocracking to produce jet fuel, kerosene, and diesel. The vacuum tower used in this process is equipped with three padding sections, three layers of the oil sump tank, three combined liquid distributors, and metal packing.

The first and second vacuum side streams are cooled down after heat exchange and either flow out as a product or return to the upper part of the first or second padding section as vacuum overhead reflux oil. The third vacuum side stream is exhausted as excess vaporization oil and is returned to the third padding section as heavy wash oil or mixed with the second vacuum side stream and flows out as a product.

If there is any residual oil left in the vacuum distillation column, it is sent to the coker unit for further refining.

Vacuum Distillation Unit

Application of Plate Heat Exchanger in Crude Oil Refining

In the crude oil refining process, there are several applications of oil heat exchangers and gas heat exchangers.

Before desalination, crude oil with a temperature of 20-45℃ passes through a heat exchanger and then enters an electric desalter after being heated to 100-150℃.

After desalination, desalted crude oil is heated to 220-240℃ and flows into the primary tower via a heat exchanger.

After primary distillation, the oil is heated to 270-280℃ in another heat exchanger.

The overhead oil gas is cooled down to 40℃ by passing through an overhead hot-water heat exchanger and air cooler, and then flows into the overhead reflux tank via the primary overhead oil heat exchanger.

The oil gas from the atmospheric overhead enters the return tank (Volume-103) for oil-water separation after being cooled to 70℃ by the overhead oil gas heat exchanger.

Non-condensable oil gas is cooled down to 40℃ by the condenser after entering the overhead product tank for oil-water separation through the overhead oil-water cooler.

The primary distilled oil is heated up to 370-380℃ by the atmosphere furnace, and then flows into the first, second, and third-line oil heat exchangers, where it is cooled down to 45℃, 60-70℃, and 70℃ respectively.

Summary

In conclusion, plate heat exchangers are an essential component in the oil and gas industry, playing a crucial role in the refining process. They are highly efficient, compact, and cost-effective, making them an ideal choice for this industry. 

Among the many plate heat exchanger manufacturers, HFM Plate Heat Exchanger stands out for its high-quality products, advanced technology, and outstanding customer service. Their plate heat exchangers have been widely adopted in various applications in the oil and gas industry and have received positive feedback from customers. With their continuous innovation and commitment to excellence, HFM is expected to remain a leading provider of plate heat exchangers for the oil and gas industry.