Industries: Petrochemical

The petrochemical industry remains significantly influenced by globalization of the world economy. Rising demand for energy has translated to declines in supply and skyrocketing costs. In keeping pace with these changes, the petrochemical industry continues to adjust through divestitures, joint ventures and other forms of partnership leading to fewer and larger producers of commodity petrochemicals with broader geographical reach. The petrochemical industry has come under some scrutiny lately as world leaders debate the role that fossil fuels have on the global climate and climate change. What is often times overlooked in this debate is the economic contributions of the petrochemical industry and the many different products beyond oil and gas that have petrochemicals as a primary building block.

Primary petrochemicals
Primary petrochemicals are divided into three groups depending on their chemical structure:
  • Olefins include ethylene, propylene, and butadiene. Ethylene and propylene are important sources of industrial chemicals and plastics products. Butadiene is used in making synthetic rubber.
  • Aromatics include benzene, toluene, and xylenes. Benzene is a raw material for dyes and synthetic detergents. Manufacturers use xylenes to produce plastics and synthetic fibers.
  • Synthesis gas is a mixture of carbon monoxide and hydrogen used to make ammonia and methanol. Ammonia is used to make fertilizer and methanol is used as a solvent and chemical intermediate.
Heat Exchangers in Petrochemical Plant

As their name implies, heat exchangers can both cool and heat water, steam, gases and hydrocarbons within a petrochemical plant. For example, petrochemical plants often produce volatile hydrocarbon samples exceeding temperatures of 500°F (260°C) that need cooling, while other fuels, such as diesel, may need to be heated before being sent to a diesel generator.

Within a petrochemical plant, liquids generally do not need to be heated, and heating may change the physical properties of a liquid so it would no longer serve as a representative sample. However, many liquids and gases/vapors within a petrochemical plant – including various glycols, olefins such as ethylene, propylene or butadiene, isomers such as benzene, toluene or xylene, and natural gas liquids (NGLs) such as ethane, propane and butane – need to be cooled. Fortunately, the right heat exchanger can cool any liquid or vapor.

Heat Exchanger Failure Mechanism:
  • Process fouling
  • Process corrosion
  • Steam/condensate corrosion
  • Stress-corrosion cracking (SCC) of tubes
Three main areas for improvement to minimize future in-service tube failures.
  • Tube testing
  • Retubing strategy during turnarounds
  • Design improvements.
Tube testing

Technologies for inspecting heat exchanger tubes are rapidly changing and continuously improving. Variance in test results depending on both the instrument and operator. The impact of human factors on non-destructive examination (NDE) performance is more prominent with the increased complexity and sophistication of today`s NDE techniques. Root cause analysis of some of the tube failures identified the need for reliable technicians and technologies. APRIS provides solution to tube inspection problems with important advantages to petrochemical industry by minimizing downtime and improving operational productivity.