Methanol (MeOH) Recovery System

Hopewell, VA
Modular solvent recovery system designed to recover MeOH from a mixed feed stream containing MeOH, IPA, Water and Solids. Three process modules and a stair tower contain a distillation column, reflux tanks, pumps and heat exchangers. An 87"ID distillation column freestands alongside the modules where it is accessed via outrigger platforms. Working in conjunction with the client, a specialty chemical producer, this system replaced and expanded the capacity of their existing distillation units.

CASE STUDY: MODULAR DISTILLATION SYSTEM TO RECOVER SPENT SOLVENTS AND EXPAND PRODUCTION CAPACITY

KochModular’s engineering team helped the client design a modular distillation system to recover and purify spent solvents, a process that is vital for the plant’s manufacturing operations. The system was fabricated and delivered under an expedited project schedule to meet a customer specified timeline

  • CLIENT: A Fortune 500 Company
  • INDUSTRY : Specialty Chemical Ingredients

KEY ENGINEERING FEATURES

  • Turnkey scope of a multi‐step separation process to recover and purify solvents including design, equipment, piping, instrumentation, fabrication, delivery, commissioning, start‐up and performance guarantee.
  • Modular fabrication design was used instead of a more costly stick‐build design, which afforded a shorter schedule.
  • Multi‐effect distillation: the overhead vapors from the first column was used as the heat source to boil‐up the second column for energy savings.
  • Extensive additional heat integration to reduce utility cost(OPEX) versus current operation.
  • Robust control scheme to accommodate variation of feed composition and product specifications.

CORE CHALLENGES

  • Process modeling of a non‐ideal, azeotropic mixture.
  • Potential corrosion and fouling due to salts in feed.
  • Hybrid modular design ‐largest shippable footprint to contain large equipment and piping, modules mated up with a large free standing distillation column.
  • Layout ‐ensuring all equipment and instruments are accessible and maintainable within the modules.
  • Minimize site interruption and production downtime during installation and commissioning of new system.

THE SOLUTION

Koch Modular was awarded this job from a repeat customer due to a successful previous project. The client had recently acquired a new plant‐site and was in the process of expanding its manufacturing operations due to increased product demand. The existing equipment was bottlenecking the process and was also at the end of its operational lifespan. Due to these considerations, the new system had to be delivered, installed and commissioned on an expedited schedule with minimal site‐interruption and production downtime.

During the front end engineering phase, Koch Modular took the client‐provided project specifications and modeled the process with proprietary simulation software. Because the solvent mixture was non‐ideal and azeotropic, special care was taken in the selection of vapor‐liquid equilibrium data.

Koch Modular used a value engineering approach and developed a multi‐step distillation system that resulted in lower energy consumption than the existing process due to incorporation of a multi‐effect distillation sequence and extensive heat integration. The general concept was discussed and reviewed with the client in detail, along with the Process Performance Guarantee that Koch Modular typically provides.

To address corrosion concerns due to salts in the feed, Koch Modular proposed using duplex stainless steel equipment and piping specifications for the front end of the process. In order to eliminate the potential for fouling, proprietary column internals were used in the first distillation column along with special considerations in there boiler design.

After the conceptual design and a proposal for the remainder of scope was accepted by the client, Koch Modular started detailed engineering and procurement. PFDs & P&IDs were developed and module design and piping layout began using 3D modeling software. Fabricated equipment was designed and purchased, and instruments were specified. KochModular participated in a client‐led HAZOP review, and then invited the client to participate in a 3D piping review that uses special software to simulate a walk‐through of the modules.This process insured that sufficient access was provided and every component was accounted for.

While the modules were being assembled, Koch Modular provided the client with information to prepare the jobsite for delivery. KochModular supplied foundation loads, anchor bolt patterns, piping tie‐in coordinates, and electrical drawings. Since the customer opted to utilize their existing control system, Koch Modular provided guidance in the form of a Controls Functional Description. In short,the client received all the information necessary to perform site preparations while the modules were being assembled, and Koch Modular supported this effort as necessary.Performing these site activities ahead of module delivery greatly streamlined and shortened the installation process.

The finalized design included the following:

  • Three process modules (each approx. 11’ x 14’ x 80’) & one stair tower
    • (1)  Distillation column (66” ID x 55’ T/T in‐module)
    • (13) Shell and tube heat exchangers
    • (6)Centrifugal pumps
    • (3) Vessels/drums
  • Free standing distillation column with operating platforms (87” ID x 78’ T/T)

Koch Modular shipped the entire project by truck to the job site after the modules had been assembled. Before the units shipped, a complete Factory Acceptance Test (FAT) was conducted, insuring that the system was ready for operation. After installation was complete, Koch Modular provided commissioning and startup services which included operator training and a Performance Test.

IMPACT

  • Koch Modular designed, built, and delivered a new modular solvent recovery system under an expedited schedule in order to meet market demand. The new system was more energy efficient that the current operation and was designed for 40% more capacity.
  • Modular fabrication allowed the new process plant to be fabricated off‐site while the client performed field installation efforts, drastically reducing project timeline and man‐power requirements.
  • Modular fabrication also allowed production to continue operations without interruption while the new distillation system was being fabricated.

WHY MODULAR FROM KOCH MODULAR?

Koch Modular used a value engineering approach during the front end engineering phase to save the client time and money, and also provided a Process Performance Guarantee to eliminate the risk of non‐performance. Our modular fabrication approach to process systems has many advantages, the main points of which are highlighted below. To learn specifically how modular fabrication achieves these benefits, please visit our website: http://www.kochmodular.com/

  • Shorter schedule/faster time to market
  • Lower cost/lump sum bid/single source
  • Minimal plant site interruption/improved safety

KOCH MODULAR PRODUCTS & SERVICES

Specialists in Process Design and Construction of Modular Mass Transfer Systems for the Chemical Processing Industry.