Project SynopsisDevelop process design information and perform a detailed technical review including process alternatives evaluations of an existing pilot-scale process that converts waste plastics/fiber to an engineered fuel product for use in power plants.
ENGINEERED FUEL PROCESS DOCUMENTATION AND DETAILED TECHNICAL REVIEW
The client, a waste recycling company, had developed a proprietary process for manufacturing an Engineered Fuel from unrecyclable plastic and fiber waste. The product is said to have the potential to replace up to 25% of coal used in coal fired power plants. Process Engineering Associates, LLC (PROCESS) was contracted to generate engineering documentation for the existing pilot plant and to perform a detailed technical review of the high temperature fusion (HTF) operation specifically so that the client would be prepared to move forward with a full-scale facility design, which is to be completed as part of a technology transfer to a third party. During the course of the project, the technical review was expanded to include other areas of the pilot plant.
PROCESS performed the following project tasks:
- Preparation of detailed heat and material balance (HMB) calculations and process flow diagrams (PFDs) for the existing pilot process already being operated by the client. This involved a detailed review of existing R&D data and minimal actual process data in an effort to define a potential envelope of operation for a process that involves processing a highly variable waste stream. PROCESS generated a design case based on the data provided by the client. PROCESS then prepared HMB calculations and PFDs for several production cases using its licensed commercial computer process simulation software (Chemstations’ CHEMCAD).
- Identification of system capacity and heat transfer issues with the existing pilot process equipment as-installed based on the HMB data generated. PROCESSidentified design issues with the existing hot oil system and rotary equipment that would prevent the client from meeting the desired throughput requirements as well as potentially lead to system safety issues. PROCESS generated a list of action items that included both equipment modifications and operating changes for the HTF system to overcome some of the shortcomings.
- Preparation of piping and instrumentation diagrams (P&IDs) for the existing pilot process for both the fiber processing area and the polymer processing area. The client requested this documentation for the existing operation so that it could be used as a basis for modifying the system as well as for future scale-up of the process.
- Execution of a detailed technical evaluation of alternative equipment and overall system configurations that would allow the client to generate the desired product. PROCESS performed a literature review for alternative equipment for both the HTF polymer processing system and the fiber processing system in the existing pilot plant. As part of this task, PROCESS prepared detailed HMB data and process schematics for four (4) technically feasible alternatives. This information will be used by the client in soliciting budget pricing for full-scale processing equipment and in selection of the final design configuration.
- Facilitation of a process hazard analysis (PHA) of the existing pilot process and development of an action items list to be addressed in both existing and scale up design.
Equipment involved in this project included rotary kiln, extrusion screw, high temperature screw reactor, rotating cone reactor, pellet mill, roller mill, grinders, hot oil systems, scrubber systems, and hammer mills.
- Waste Recycling / Alternative Fuels
- Pilot plant review
- Pilot plant optimization
- Process scale up alternatives evaluation