A new pilot plant has begun operating at InChem Corporation, a toll manufacturing company located in Rock Hill, S.C. This new installation can provide small batches for chemical process development, process optimization, or limited quantities of product for internal evaluations or customer sampling. The facility has a modular design which allows equipment to be configured for a variety of operational situations.
Located in a dedicated building, the pilot plant has more than ample space for configuration of ancillary equipment, staging of raw materials, and privacy for our clients. Operations in the pilot plant are carried out and supervised by the InChem technical staff.
Pilot Plant Equipment
Two 316 stainless steel reactors are the heart of the pilot plant. The area is a Class 1, Division 2 location where flammable solvents can be safely handled. All process equipment can be rendered inert with nitrogen, which is hard-piped into the facility.
The smaller, 5 gallon reactor is fitted with an electrically driven helical or ribbon agitator which can process high viscosity products. This agitator can be fitted with Teflon wiper blades. It is capable of operating pressures up to 200 psi to full vacuum. The minimum operating volume for the 5 gallon is about 2 gallons.
The larger, 30 gallon reactor has a spiral, propeller agitator which is electrically driven and works best with lower viscosity liquids. The agitator seal on the 30 gallon reactor can operate up to 40 psi to full vacuum. Minimum working volume in this vessel is roughly 10 gallons. The vessel is mounted on load cells. A sightglass can be attached to the bottom discharge valve of the reactor to facilitate phase separation of aqueous and organic layers.
The reactors are heated using a hot oil system which is dedicated to the pilot plant. The 50,000 BTU Chromalox unit can provide jacket temperatures to 270o C. Other equipment in the facility includes two oil sealed, vacuum pumps which can provide controllable operating pressures in the reactors below 50 mbar. The pilot plant has a dedicated chiller providing chilled water for the condenser, jacketed receiver, and cold trap prior to the vacuum pumps. Compressed air and nitrogen are hard-piped into the facility such that there are no supply limitations for these utilities.
Sensors collect data from a variety of locations throughout the pilot plant. These include vessel internal temperature, pressure, agitator speed, condenser inlet and outlet temperatures. Operating parameters for the utilities include hot oil supply temperature and flow, oil return temperature, chilled water temperature, and pressure at the inlet of the vacuum pumps. All data is stored and analyzed using Wonderware Historian.
Pilot Plant Features Modular Configuration For Flexibility
The modular configuration of the pilot plant allows for convenient incorporation of ancillary equipment to meet customer requirements. InChem can provide filters or a small belt flaker. Other equipment could be incorporated into the pilot plant with cooperation of the client such as high shear mixer, centrifuge, or an external circulation loop for in-line testing.
The operation at InChem is suitable for a variety of process chemistries. These include: esterification, transesterification, epoxidation, isocyanate reactions, silicone chemistry, and acrylic emulsion or solution polymerizations.
Projects in the pilot plant go through a rigorous evaluation process before the batch is run. Clients are heavily involved in the process. Safe handling of raw materials and products, compatibility of 316 stainless steel with the prescribed chemicals, estimated cycle time, and sequencing or critical process events, and required analytical tests are considered. After the initial considerations, a detailed operating procedure is developed by InChem for review by the client. This procedure (the InChem jargon for the procedure is a “batch sheet”) then serves as the basis for a PHA (process hazard analysis). After the PHA a final procedure is written and “signed off” by InChem and the client. With the final batch sheet, the process in the pilot plant can be started. With the completed batch sheet and PHA, about 80 percent of the work necessary to scale-up the process into larger equipment at InChem has been completed.
QC-Analytical Laboratory Supports Pilot Plant Operations
InChem has an on-site QC/analytical laboratory to support pilot plant operations. The lab is staffed by degreed chemists and operates 24 hours a day. The lab routinely runs a variety of tests. Instrumental capabilities include gas chromatography (GC), high pressure liquid chromatography (HPLC), infrared spectroscopy (FTIR), and UV-vis spectroscopy. Routine wet chemical methods include: viscosity, density, acid number, amine number, isocyanate content, and epoxy equivalent weight. Other methods may be introduced in the lab based on customer methods. InChem has relationships with external partners for more specialized testing such as elemental analysis by ICP, NMR and DSC.
At the end of a batch or campaign, a report is prepared by the InChem technical staff which includes a summary of the process, properties of the product in comparison to the desired properties, safety concerns or issues, areas for improvement, and considerations for moving the product to larger scale equipment. The report, batch sheet, and analytical data are all property of the client.
Pilot Plant Clients Are Encouraged To Participate
Clients are encouraged to participate in all planning sessions for pilot plant operations. InChem especially encourages our partners to be on-site during pilot plant runs. This allows for good cooperation during the process and efficient decision-making as the process is running. A private office is available to our clients while in Rock Hill.