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New microreactors and flow loops improve asphaltene management

| By Mary Page Bailey

Asphaltenes are an ultra-complex fraction of crude petroleum that comprise a diverse population of molecules that vary in size, solubilities, aggregation states and hetero-atom contents. Asphaltene buildup and deposits create many operational and safety issues, and can occur anywhere in crude-oil production systems where favorable conditions exist. Despite their prevalence in the oil-and-gas industry, much is still misunderstood about asphaltene chemistry and control.

A new research initiative launched by ChampionX (The Woodlands, Tex.; www.championx.com) is designing new testing and evaluation methods to create more effective chemical formulations for asphaltene control that can be easily transferred from the laboratory to the field. “We are developing better methods that narrow the gap between asphaltene-control chemical performance in the laboratory and performance in field applications. By adopting better crude-oil storage and handling for asphaltene-control testing, the chemical development and qualification process can be improved substantially,” says Chris Russell, corporate scientist at ChampionX.

Source: ChampionX

To tackle these concerns, the team developed a high-pressure, high-temperature flow loop where asphaltenic crude oil is subjected to field-relevant temperature and pressure conditions in the presence of heptane or propane. “This system has differential-pressure monitoring capabilities and can provide a qualitative, real-time deposition risk prediction during test runs, enabling the optimization of chemical supply. We have also developed a new microreactor methodology for asphaltene-deposition evaluation. This test provides a rapid measure of asphaltene deposition that can deliver effective chemical formulations in more elaborate detail, even in field applications, to help in preserving the integrity of assets,” explains Duy Nguyen, senior fellow at ChampionX.

The asphaltene rocking-cell and flow-loop methods test the effect of different chemicals to provide qualitative risk assessment for asphaltene precipitation, agglomeration and deposition. Results of these tests support the selection of the optimal chemicals to treat each scenario. The team also developed a series of complex testing processes to address precipitation, agglomeration and deposition control. This research has highlighted the fact that synergistic combinations of kinetic asphaltene inhibitors with the correct concentration of dispersant can effectively control the size of asphaltene agglomerates.