May 2017

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Water Management: How mobile water treatment solutions can benefit refineries

The Coffeyville plant is the only operating plant in North America using a petroleum coke gasification process to make hydrogen, a key ingredient in its manufacturing process.

Reyes, M., Veolia Water Americas

Coffeyville Resources Nitrogen Fertilizers LLC is a subsidiary of CVR Partners that directly owns and operates the Coffeyville Nitrogen Fertilizer Plant. The Coffeyville plant is the only operating plant in North America using a petroleum coke gasification process to make hydrogen, a key ingredient in its manufacturing process. In 2015, the plant produced 385.4 Mt of ammonia and 928.6 Mt of urea ammonium nitrate (UAN). Approximately 96% of the ammonia produced, and most of the purchased ammonia, was upgraded into UAN. The Coffeyville Resources Refining petroleum business includes a complex full coking, medium-sour crude oil refinery with a capacity of 115 Mbpd, and also provides the necessary pet coke feedstock for the nitrogen fertilizer plant.

In the spring of 2015, the nitrogen fertilizer plant faced challenges with increasing demand for plant service water, and the degradation of river water quality. The Verdigris River turbidity and suspended solids concentration had climbed significantly, reaching well over 200 NTU from the continued heavy rains of the season. To address these challenges, CVR utilized a mobile water solution.

A temporary mobile water clarifier trailer was deployed to the Coffeyville site. It was placed into service, and provided more than 1 MMgpd (million gallons per day), enabling the existing cold lime softening infrastructure to run at more desirable rates. To ensure that the mobile system continues to meet the needs of the facility, a chemical management team maintains a thorough understanding of the river quality and plant’s water system, enhancing the overall service value.

Traveling technologies for a variety of situations

Mobile water solutions can cover emergency, temporary or long-term water treatment needs. The trailers are typically deployed via stand-alone units, or in combination, to form complete systems with state-of-the-art purification technologies. A mobile water solution allows refineries to combine various technologies, proprietary chemistries and field services, and provides the flexibility to choose a stand-alone mobile equipment rental or a complete, integrated service.

FIG. 1. A view of the mobile water clarifier.
FIG. 1. A view of the mobile water clarifier.

Delivered via trailers, containers and/or skid-mounted systems, mobile-deployed processes can include clarification, membrane filtration, reverse osmosis, softening, demineralization, ion exchange and multimedia filtration (FIG. 1). Among the potential applications are physical and chemical separation for suspended solids, turbidity, hardness and metals removal; reverse osmosis membrane separation and demineralization for total dissolved solids (TDS) reduction; and specialty ion exchange for heavy metals removal.

Due to the flexibility of a mobile solution, the portable technologies can be applied to any stage of a refinery’s water cycle. In practice, mobile water services are typically used for:

  • Emergency situations, where a malfunction of existing equipment requires quick, emergency service to enable continued plant operations.
  • Planned maintenance to allow existing equipment to be taken offline for maintenance or repairs.
  • New plant processes, requiring additional water treatment capacity, such as changing a feedstock.
  • Temporary treatment when additional water treatment is needed, such as for temporary changes in production rates.
  • Plant expansions in which increased production demands require additional treatment capacity.

Temporary solutions can reap long-term benefits

The ability to bring in mobile solutions eliminates the need for production outages during emergency or planned maintenance. In addition, the temporary rental of water treatment equipment can reduce or delay capital expenditures (CAPEX) for treatment plant modifications. Implementing a mobile treatment train can also serve as a trial period for the addition of new technology or process modification, enabling process optimization prior to the design of a permanent system. The result could be significant savings in both the CAPEX and OPEX of a water treatment project. HP

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