The drive by some chemical companies to improve energy efficiency extends well beyond their production processes. For instance, Eastman Chemicals, BASF, AkzoNobel and Dow are working hard to find energy savings in all aspects of corporate life.
One of the main efforts of Kingsport, Tenn.-based Eastman Chemicals focuses on reliable supply of high-pressure steam for powering several large compressors for the cracker at the company’s Longview, Texas, plant. The steam comes from either an on-site cogeneration facility or less efficient boilers within the cracker operation itself. The reliability problem was highlighted one night last year when the limited turndown of the cogeneration facility forced the shutdown of one of its two combustion turbines. This reduced the reliability of the high-pressure steam supply, causing the cracker to produce the steam using its own boilers.
To solve this problem, the company has installed novel burner technology in the two cogeneration combustion turbines. This greatly increases their turndown, allowing both to remain online at all times.
“This improved steam reliability to the point that high-pressure steam production could be shifted from the cracker to the cogeneration plant. The two units worked together to reduce the cracker boilers use and increase the steam from the cogeneration plant. Controls were installed to control the steam header pressure while minimizing steam produced by the boilers. In all, the project will save 156,000 MMBTU/y,” explains Sharon Nolen, Eastman’s manager, global natural resources management.
Since 2012, Eastman has been collaborating with Purdue University, West Lafayette, Ind., and the Process Science and Technology Center at the University of Texas, Austin, in an ongoing effort to improve the energy efficiency of its energy-intensive distillation units using dividing-wall column technologies. To date, Eastman has committed over $1.5 million in funding to the project.
“Distillation accounts for roughly 40% of all energy consumed by industrial chemical processes. Our efforts thus far have shown that new distillation schemes/technology can reduce the energy consumption by up to 50% and the capital investment by over 30%,” notes Scott Owens, Eastman’s scale-up project leader.
The academic collaborators currently are evaluating system selection, column design/construction, process simulation and operation/control of new distillation technology.
“This work gave us a significant jumpstart on our internal efforts to add or upgrade experimental facilities and understand and apply the new technologies to our own proprietary processes. We have already identified several processes which would see large financial benefits from retrofitting to a more-advanced distillation technology. In many cases, the process would enable reduced energy intensity and line expansion with minimal capital investment,” he adds.
The company also is tackling non-process-related energy inefficiencies. For instance, a project to upgrade lighting is underway at various company sites, building on ongoing efforts at the Kingsport headquarters. “The majority of installations involve replacing less efficient lighting with LEDs [light-emitting diodes]. Energy savings for 2016 equate to more than $390,000,” says Lisa Lambert, Tennessee site energy coordinator.
Broad Energy Certification
For its part, BASF, Ludwigshafen, Germany, is committed to achieving certification to the ISO-50001 energy management standard by 2020 for the sites that account for 90% of its total purchased energy. It also aims to increase energy efficiency in its production plants by 35% by the same year (2002 baseline).
In North America, this so far has involved the implementation of 14 energy efficiency projects at seven different production sites.
Among these is a project at its Wyandotte, Mich., complex. In 2014, site management learned that Wyandotte Municipal Services would stop providing steam to the site after 2016. After evaluating nine different options, the site decided to reactivate a large steam plant that had stood idle for more than a decade. Over the next two years, a project team converted the plant, which originally was coal-fired, to natural gas. This involved installing high-efficiency natural gas burners, a new control system and water-treatment system, enhancing the plant’s electrical infrastructure, and hiring a team of ten employees to run the unit. The steam plant began operating at the end of last year (Figure 1).
“The project at our Wyandotte site exemplifies our strategic approach to integrate energy management goals into our efforts to optimize our processes at BASF,” stresses Ty Geiger, vice president of energy management, BASF, Houston. “It is for these efforts that BASF has been recognized by the American Chemistry Council for its energy efficiency improvements for 20 consecutive years,” he adds.
Efforts, of course, are taking place worldwide. For instance, BASF has been implementing a “triple E” (excellence in energy efficiency) project at its Guaratinguetá complex in Brazil where 12 plants with a total capacity of over 260,000 t/y manufacture more than 750 different products (Figure 2).