Automation of Water Resource Recovery Facilities. Water Environment Federation

wastewater treatment project. However, previous experience with particular products and their manufacturers should also influence the final decisions. As stated previously, it is also important to solicit owner input during the selection process to match existing equipment, if appropriate, or to exclude other equipment and vendors based on the owner’s experience. Phone surveys and site visits are a good way to obtain first-hand experience with unfamiliar products. Previous experience by other owners is also valuable information to solicit during the selection process.

2.3.2.2 Incorporating Selected Technologies to Design

      When designing a control system for a WRRF, engineers must accommodate multiple vendor and equipment variations. Public works projects typically are awarded to the lowest bidder, who often chooses the least-expensive instruments that meet project specifications. As such, engineers must allow for such eventualities and adjust the design accordingly. For example, space must be allocated to accommodate differences in dimensions among various vendors’ equipment. Fortunately, wiring for most WRRF instrumentation has been standardized (e.g., 4- to 20-mA outputs, standard protocols [i.e., HART and Fieldbus]). Smart instruments incorporating wireless technologies and Ethernet communications should also be considered; these technologies are becoming more mainstream at industrial sites and may provide the solution to specific facility needs.

2.3.3 Books and Periodicals

      “Low-tech” media such as books, journals, and magazines are great sources of technical information. Many instrumentation, control, and automation trade magazines also publish annual vendor guides. For more information, see the “Suggested Readings” section at the end of this chapter.

2.3.4 The Internet

      2.3.4.1 Web Sites

      The Internet is a vast pool of information that can sometimes be overwhelming. A good place to begin research is by using a general search engine (some popular search engines are listed in the “Suggested Readings” section at the end of this chapter). Useful information is also available on Web sites of industry organizations such as WEF (http://www.wef.org), ISA (http://www.isa.org), and ITA (http://www.instrument.org).

2.3.4.2 Social Media

      There are numerous blogs, training videos (on YouTube and other Web sites), and tutorials dealing with automation and instrumentation specifically geared to the wastewater industry, including specialty groups in LinkedIn, Twitter, Facebook, and other social media outlets.

2.3.5 Training

      Appropriate training in instrumentation and control systems can be obtained from many sources, including universities, technical societies, vendors, and experienced colleagues. For example, some technical societies now offer Internet-based training, which allows individuals to earn professional development or continuing education credits without having to travel. In addition to online presentations, this training approach allows students and the instructor(s) to interact via a phone link. In addition, vendors often offer introductions to their product line via free seminars that can be held at either the engineer’s or the vendor’s facility. Most vendors also offer some form of training on their products and services that typically is tailored to users (see Chapter 16 for more details).

2.3.6 Previous Design Experience

      Many engineering firms offer a wealth of experience and can be a tremendous asset to users who may lack the time or resources to undertake the work themselves.

3.0 POSTDESIGN PHASE

      3.1 Design Services During Construction

      During project implementation, the design team should be involved in shop-drawing reviews, change-order preparation, and contractor and vendor meetings. In addition, the team should also respond to requests for information (RFI) and witness control system factory testing and other construction-assistance related activities during this time to ensure that the final control system will function as intended.

3.1.1 Submittals

      Contractors and system integrators typically prepare detailed drawings of instrumentation systems before installing them. These drawings include loop diagrams, panel drawings, manufacturers’ data, PLC programs, DCS configuration, interconnecting wiring diagrams, and so on. The design team should thoroughly review these documents to ensure that they comply with the design’s requirements. The following is a list of submittals typically expected from the contractor or system integrator for the automation portion of a WRRF:

      • System integrator technical proposal;

      • Automation system project schedule;

      • Control system architecture;

      • Instrument data sheets;

      • Detailed panel drawings, including layout, wiring schematics, and so on;

      • Automation equipment hardware;

      • Instrument installation details;

      • Software

       Human–machine interface,

       Programmable logic controller program listing,

       Distributed control system configuration,

       Simulation programs for factory acceptance test,

       Historian configuration,

       Alarm management,

       Intelligent asset management and computerized system, and

       Maintenance management systems; and

      • Alarm notification systems.

3.1.2 Change Orders

      3.1.2.1 Change Order Management

      A certain amount of change orders are inevitable for a project. Changes can be caused by user requests, design omissions, design errors, field conditions, or unforeseen situations. When such changes occur, design engineers should evaluate them, estimate their costs, and produce the documents needed to support them.

3.1.2.2 Common Risk Areas for Change Orders

      It is important to agree on a scope of work with the contractor or system integrator before proceeding with processing of the change order. This will avoid misunderstandings between the contractor and engineer as to what is being provided. In addition, upgrade and expansion work on an operating facility is more time consuming than work on a new facility and requires a lot more coordination with the facility to ensure uninterrupted or minimal effect to operations.

3.1.3 Responding to Requests for Information