Project SynopsisIdentify process changes to reduce cycle times of a silica based batch chemical reaction process and develop process engineering documentation to facilitate the implementation of these improvements.
BATCH REACTOR CYCLE TIME REDUCTION PROJECT ALTERNATIVES EVALUATION and DESIGN
The client, a world-wide chemicals and materials manufacturer, contacted Process Engineering Associates, LLC (PROCESS) to perform a technical alternatives evaluation to reduce the cycle time on an existing batch reactor at one of their U.S. facilities. A production area at the facility which produces a silica based product, has a single reactor with two regenerators. The reactor was gravity drained into a regenerator at the completion of a reactor cycle. The existing draining procedure was slow and if done faster a new batch could be started quicker, thus decreasing the overall process cycle time. The purpose of this project was to evaluate and select the best alternative to reduce the existing batch reactor cycle time and to develop conceptual level design documents for the selected alternative.
Project tasks included the following:
- Preliminary process design basis preparation
- Process alternatives identification
- Alternatives technical and economic evaluations
- Selected alternative for Process Flow Diagram (PFD) development
- Modified preliminary piping and instrumentation diagrams (P&IDs) preparation
- Major process equipment and instrument duty specifications preparation
- Preliminary capital cost estimate preparation
- Develop rate model for proposed system and evaluate production increase
- Process hazard review of the proposed system
- Develop tie-in P&ID for the new system
- Choose site location of new system
- Develop as built P&ID for demolition and tie-in drawings.
After reviewing the available information gathered to date as well as discussions with client project team members, PROCESS developed the baseline information that governed subsequent process design tasks.
PROCESS executed technical and economic evaluations for processing alternatives selected for evaluation for draining of the reactor and subsequent draining of the regenerator at the completion of a batch cycle. The technical evaluation involved comparison of the alternatives relative to items such as commercial experience, simplicity of operation, flexibility of operation, maintenance requirements, quantity/quality of waste generated, and relative (order of magnitude) capital and operating costs etc.
PROCESS developed a detailed process flow diagram for the selected alternative. PROCESS developed a comprehensive mass and energy balance for the modified process that included major, minor, and utilities streams flow rates, compositions, temperatures, pressures, and applicable physical/chemical properties. This involved the set-up of the process simulation model in CHEMCAD software as well as an Excel based analysis. The information was then used utilized to generate a PFD that depicted the primary unit operations and major process and utility streams. The PFD was prepared using AutoCAD software using PROCESS drafting standards.
PROCESS utilized the information gathered and generated to modify the existing P&IDs to reflect the proposed modifications. PROCESS also prepared a general process controls description that described in words the functionality of all major process controls, monitoring points, alarms, and interlocks set forth in the P&IDs. Process prepared preliminary specifications for all new major process equipment and any new major instruments.
PROCESS developed an estimate for completing design, procurement, and installation of the reactor/ regenerator modifications. PROCESS solicited information from qualified equipment manufacturers to obtain budgetary equipment and instrument purchase price information. For standard equipment and instruments, PROCESS used information contained in in-house equipment cost information or relied on previous information gathered by the client. This information was summarized and formed the basis for a factored capital cost estimate (CAPEX).
- Specialty Chemical Manufacturing
- Batch reaction cycle time analysis
- Process evaluation
- Process improvement engineering.