An Introduction to Process Engineering and Design
Process engineers are responsible for designing manufacturing plants that transform raw materials into consumer products or other discrete materials. Throughout process engineering and design of manufacturing equipment, process engineers work closely with industrial manufacturers (chemicals, oils, and petrochemicals, alternative energy, etc..) and sanitary manufactures (pharmaceutical, food and beverage, consumer products, etc..) to optimize their chemical processes, controls, and overall plant design efficiency.
Process Engineer Responsibilities
When it comes to manufacturing plant design, a process engineer’s responsibilities can be wide-ranging. Often, manufacturing companies hire process engineers as “project engineers” to manage several stages of a plant design project. This can include designing process systems, providing cost estimates, equipment selection and layout, overseeing process skid fabrication, process control configuration and much more. In this blog, we’ll review the role of a process engineer in manufacturing and the breadth of a process engineer’s responsibilities during plant design projects.
Engineering Studies & Front-End Engineering Design (FEED)
The concept stage is the first step of any plant design project. What is the problem you’re trying to solve? What’s the best way to solve it? This is where a process engineer can step in. Whether the manufacturer already has a full process flow diagram (PFD) or just a sketch on a napkin, top process engineering consultants can flesh out project specifics and provide the steps required to reach an efficient solution.
Before a project gets rolling, a process engineer might recommend a feasibility study to provide a better picture of the viability of the proposed commercial process. This helps the manufacturer set reasonable expectations for their production. A process engineer can also conduct several additional engineering studies including HAZOP, safety, area classification, ergonomics and more.
Process engineering companies can also provide front-end engineering design (FEED) services. FEED provides the manufacturer with a cost estimation for their skid fabrication or plant design project. These estimates can range anywhere from a rough order of magnitude, which approximates the overall project value, to a fixed bid quotation, which totally defines and solidifies the project scope and costs. The level of completeness for the estimate depends largely on the amount of information the process engineer has at their fingertips.
Process Engineering and Design of Systems
The main role of chemical process engineers is usually to complete detailed process system design. This includes developing documents and designs including:
- General Arrangement Drawings
- Process Flow Diagram (PFD) – outlines the major chemical and equipment requirements of a process plant or process skid, as well as the general flow of the manufacturer’s new process.
- Piping and Instrumentation Diagram (P&ID) – specifies all of the valves, pipes, tanks, instrumentation, and equipment required to safely meet the precise scope of the plant design or skid fabrication project.
- Welding Procedure Specifications (WPS) – this document outlines pipe thickness, size, material construction, the technology used to weld pipes (or tubes and other structural metal of the process skid) together. A process engineers would likely work with quality assurance specialist to identify these parameters before seeking approval from the manufacturer.
- Mass & Energy Balances – conservation of mass and energy to the analysis of physical systems
- Equipment, instrumentation and valve lists
- Materials of Construction Guidelines
- Electrical design documents
- 2D & 3D process models – Some process engineering companies collaborate with process skid designers who create 2D and 3D visualizations of how a process skid will fit inside of the manufacturer’s plant prior to fabrication and installation. In some cases, process skids are designed modularly for ease of transportation from the shop to the plant.
- Process simulations – for determining the chemistry/chemical interactions (Read more about process simulations here)
- Mechanical & structural design documents
As experts in process chemistry, process engineers are focused on how the chemical interactions involved scale and interact with process equipment. Process simulations, mass and energy balances, and 2D/3D process models are the main ways these interactions are explored and designed for. These tools are used to optimize the chemistry and process flow while maintaining safety and industry standards. The other documentation listed above is produced to give process equipment fabricators with specifics around exact equipment, piping layouts, instrumentation, and fabrication procedures to successfully implement the process engineer’s design.
Similar to the chemistry of a process, equipment layout and design requires a high level of expertise and competence from a process engineer. For example, to maximize accessibility, a process engineer might arrange equipment around the outside edges of a skid, to provide both outside access and an inner pathway down the center of the skid. Similarly, logistical factors, such as floor space availability in the manufacturing plant, must be considered during process skid design.
Process Control Engineering
Process engineering and mechanical design are only part of a plant design project. Process engineers often work in tandem with process control engineers. Unlike process engineers, process control engineers focus on the electrical component of plant design projects.
Process control engineers are responsible for control panel design, electrical design and power distribution, data collection systems and generally automating industrial processes. They’re also responsible for programming programmable logic controllers (PLC), distributed control systems (DCS), human machine interfaces (HMI) and other industrial automation equipment.
Turnkey Process Systems
EPIC Systems is a process engineering and skid fabrication company employing process engineers who take turnkey responsibility for plant design projects, covering all of the stages mentioned in this blog. To learn more about EPIC’s turnkey plant design and process engineering capabilities, contact us or call 314-806-1678.