Pilot Plants

Session Chair & Co-Chair:

• Ross Topliff, Tops Engineering
• Donald Todd, T&T Solutions

Session Description:

Whether scaling up a laboratory process or working on process optimization, we often need to run the process in pilot-scale equipment to check certain aspects of the process. Unless it is dedicated to a single product or process, the pilot plant must remain flexible to allow changes to present and future operations. This session will explore some of the challenges present in laying out and operating a pilot plant along with recommendations on how to maximize the space utilization. It will include procedures to help improve the effectiveness and sustainability of a process.

Schedule:

Successful Scale-up and Piloting - Overcoming Challenges Other than Obvious Technical Issues

Rudolph Krack, Virginia Commonwealth University

Scale up and piloting is one of the most challenging steps of bringing a new product or process to market.  It’s a technology transfer process between individuals from different parts of an organization; possibly from different organizations; even from different counties.

Scaling up a process by a factor of hundreds or even thousands from laboratory glassware to pilot scale equipment has many expected technical issues to resolve, such as heat and mass transfer differences.   But there are also personal and company cultural issues involved such as plant personnel interacting with corporate development staff, chemical engineers interacting with chemists.  The knowledge and information to be assimilated and transferred is usually more important than the material actually produced in the piloting phase.

This presentation will touch on several of these non-technical issues, based on the author’s experiences in scale up and transfer of products with several organizations’ pilot facilities.

An Integrated Biorefinery Pilot Plant

Ravi Chandran, ThermoChem Recovery International

We offer a proprietary two-stage gasification technology for carbonaceous feedstock such as woody biomass, agricultural waste, Municipal Solid Waste (MSW) and young coals that has some unique attributes: production of a medium calorific value syngas, ability to dial in the H₂ to CO molar ratio to match the synthesis reaction step for biofuels and/or biochemical production, feedstock flexibility, generation of the highest syngas flow for synthesis reaction due to the indirect heating method, and opportunity for superior thermal and process integration.

In order to validate and demonstrate the technology and generate scalable data that confirms the design and warrant the commercial system, we initially proposed to design and build a pilot plant gasification and gas cleanup system. Later, with a first commercial product target of Fischer-Tropsch (F-T) liquids it was realized that the pilot plant needed to represent and include every single unit operation envisaged in the commercial system for technology success. Therefore, we designed, constructed, commissioned and performed trials at an integrated biorefinery pilot plant at Durham NC. This plant is designed to process 4 dry tons per day of carbonaceous feedstock, generate, clean up, compress and condition syngas, and catalytically convert it to F-T liquids. It comprises the following sub-systems: feedstock storage and feed system, gasification system, primary gas cleanup system, secondary gas cleanup and conditioning system, synthesis reactor system and a Regenerative Thermal Oxidizer (RTO). The feed system is capable of feeding a wide range of feedstocks.  The gasification system uses proprietary indirectly heated gasification technology.  The synthesis reactor is an Emerging Fuels Technology (EFT) F-T reactor with their proprietary cobalt catalyst to produce fuels and waxes. The PDU is designed to be integrated to any number of alternate downstream catalytic or fermentation processes to produce fuels and chemicals from syngas. Feedstocks tested to date include woody biomass, agricultural waste, switch grass and MSW.

The feed system and gasifier have operated for more than 8,000 h, and the pilot plant has operated in the fully integrated mode, generating F-T products for 2,800 h, all on woody biomass. The trials have demonstrated clean syngas production with stable H₂ to CO molar ratio (~1.9), 60+% CO conversion in a single stage of F-T and the generation of high quality, sulfur-free, 100% renewable fuels i.e. pure white wax and water clear, medium fraction hydrocarbon liquids.

Many challenges were encountered in design, equipment selection, instrumentation, installation, commissioning, shakedown and operation. Standard engineering tools such as computer-aided engineering, design review, Hazop analysis, project management, quality control and root cause analysis were utilized to successfully complete the tasks. This story or experience from idea to results will be presented. 

Filtration, Cake Washing & Drying: Lab Testing to Pilot Testing to Project Installation and Performance Guidelines

Barry Perlmutter, BHS-Filtration Inc.

This presentation will discuss lab testing, pilot testing, scale-up,  installation and performance guarantee for a candle filter technology.  The overall scheme can be used by process engineers to develop optimum filtration solutions for pressure or vacuum, batch or continuous and high-solids to clarification applications.

The original process filtered a specialty chemical in a filter press using a paper filter media at 170 degrees C.  Diatomaceous earth and/or activated carbon were used as a body feed and precoat. The process had the typical problems associated with a filter press including bypass of slurry, manual operation, filter media plugging, non-reproducible quality plus the safety concerns of being burned with hot oil.

Application testing began in the laboratory using the a Pocket Leaf Filter.  These tests determined the filtration pressure, cake thickness, filter media, cycle times and other parameters such as filtrate quality and final moisture content.  The lab testing showed that the Candle Filter technology worked very well for this application.

Following the lab testing, the plant then rented a pilot candle filter with 1 m2 of filter area.  The testing objectives were to confirm the laboratory results, observe cake discharge and develop the design parameters for the final scale-up and performance guarantees.

The presentation concludes with a description of the installation, PLC controls and performance guarantees.