Project SynopsisProvide engineering services for the creation of process modeling tools to for predictive use in a variety of soil decontamination process configurations.
SIMULATION OF CONTAMINATED SOLIDS/SOILS THERMAL DESORPTION AND GAS CLEANING SYSTEMS
The client is an environmental consulting company that is a worldwide specialist in the evaluation, design, operation, testing, regulatory evaluation, and permitting of thermal treatment systems used to remove and/or destroy hazardous chemicals from the soils of sites that have been contaminated. A number of different types and combinations of thermal equipment, heat recovery equipment, solids handling equipment, and off-gas cleaning equipment can be used to accomplish decontamination. As part of its services, the client is routinely required to develop and use process simulations of these many potential process equipment combinations and to calculate the flows and compositions of process streams for such purposes as equipment sizing, equipment operational trouble shooting, stack emissions evaluation, etc.
Process Engineering Associates, LLC (PROCESS) was contracted by the client for a number of different projects to prepare process simulation models for several of the combinations of thermal desorption, solids handling, heat recovery, and gas cleaning system process units to be potentially used by the ultimate clients. The following are the types of thermal processes used for decontamination that were modeled:
- Batch box thermal desorber systems
- Indirect heated rotary dryer systems
- Direct fired rotary kiln dryer systems
- Direct fired rotary kiln incineration systems
- Pugmill systems for cooling treated solids.
Gas cleaning processes that were modeled included:
- Gas-to-gas and gas-to-liquid heat exchange for heat recovery
- Thermal oxidation for destruction of the hazardous organic chemicals desorbed from solids
- Wet and dry scrubbing for acid gas (SO2SO2 and HCl), particulates, heavy metals, and mercury removal from desorption system off-gas.
Based on sets of Excel calculations previously developed by both client and PROCESS personnel, PROCESS developed two (2) generalized process simulation models in Excel. One model was specifically for the batch box process. The second model was designed and built as a general model that could be configured for all thermal desorption processes and all associated solids handling, heat recovery, and gas cleaning processes described above. Each model included the capability for accepting inputs from PROCESS‘ licensed commercial simulation software (CHEMCAD).
PROCESS trained the client personnel in the use of the models. On several occasions, PROCESS was called on to configure the models for some of the ultimate clients’ specific applications, including for the removal and recovery of crude and processed oil, which required further use of CHEMCAD to enable calculation of vapor liquid equilibrium for the different oil components.
- Environmental Decontamination Services
- Process modeling tool development
- Process simulation