Objective:

A dairy farm was in the middle of a project that involved the process of implementing renewable natural gas capturing. The customer brought Revere in to support the current operations at the biogas plant. Revere was tasked with resolving the existing issues as already-completed portions of the project were not working as expected and with completing the work initiated by another controls integrator on the PLC and SCADA system.

Revere was asked to undertake a turnkey project to stabilize the controls strategy at an RNG facility in Stanfield, Arizona. The project included consulting, sitewide controls integration, power design, networked MCCs, instrumentation specifications, support contracts, and various additional projects. The operator and investors needed the facility online and generating ROI as soon as possible, as the project was behind schedule.

Description of Services Provided:

The project was completed in two phases.

Phase I was a time and materials assessment for the development and testing of the digester control software and HMI configuration. It included an initial site visit with the assigned project manager to determine the needs of the site and an equipment and software audit for the programming to be provided.  Revere’s team researched the level of documentation of the facility and collected the needed programs from the existing control system. The assessment prepared Revere to define a program testing plan and to execute the necessary rewrite of the PLC code and the HMI.  The IT Engineer was onsite to evaluate and address IT activities; and the FTSE Historian (OSI Pi) was reviewed to ascertain that the data was collected correctly and available in a useable format. The site visit allowed Revere to assess control panel, instrumentation, and electrical needs necessary to prepare a fixed price proposal for the hardware and services necessary to complete the Phase II digester controls.

For Phase II of the project, Revere deployed our Get2Gas packaged solution to get the facility fully operational:

  • Programming services utilizing the Rockwell Automation Studio Control system for the two Additional Digesters and supporting processes.
  • Integration of the new 3rd Party Skid mounted controls for the Amine System, Heat Exchangers, and other 3rd party systems necessary for proper control of the process.
  • Revere’s custom panel fabrication excelled at the just in time delivery philosophy:
    • A remote farm’s integration was demonstrated in Birmingham and commissioned on-site.
    • The (10) panels seamlessly integrated with their process.
    • The Clarifier’s E-house was delivered one week, then operation for functional testing the next week.
  • HMI programming services to create new graphics that integrate the new digesters with the current Rockwell Automation Factory Talk application.
  • Revere provided, developed, and demonstrated the new software function as part of a factory acceptance testing procedure.
  • Start-up and commissioning included:
    • Project management and back office support
    • Championed the various Cause & Effects to encourage a documented design
    • Created loop checkout folders for each phase
    • Lead the checkout with the support from the local technician(s)
    • Performed online operational training
    • As-built drawings

One key issue the plant had was controlling their flare blowers. The control sequence was designed poorly and PID loop not tuned properly. Working with the operations team, we developed a sequence of operations and commissioned the newly tuned PID loops that helped their plant run with less process upsets. Tightening the control loop on the flare blower system minimize the amount of gas that was sent to the flare. This helped to increase throughput for their process which, thus, decreased the amount of methane and other gases that were burned in the flare.

Customer Results:

Revere really sought to understand key performance indicators (KPIs) for the customer. Once we understood, we were able to make control system changes that helped the customer better view data on how the plant was performing (daily gas totalizers, trending, etc.). For a client that “didn’t know what they didn’t know”, this was critical to success. Revere had to manage various contractors and engineering firms to consistently deliver an accurate product in the end. The project was delivered on time and on budget, and the client has plans to work with Revere again in the near future.