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Start-up of new or modified facilities and training of operations personnel to operate the processes is the last critical step in the implementation of any pollution control technology. Start-up procedures and the training of new or experienced personnel must be very carefully planned in order to meet start-up schedules in a safe and effective manner. The essential elements necessary to establish an ongoing successful operation are de- scribed below.

Equipment Checkout

The start-up team generally becomes involved in a project when construction is nearly completed and equip- ment checkout is required. In many cases, the construction contractor will have responsibility for assuring the operability of all mechanical equipment, electric motors, and instruments, and the integrity of all piping, ductwork, and tankage. However, this normally does not include the responsibility to put the process into op- eration as a system.

Therefore, the first activity of the start-up team is to review the equipment checkout activities, including instrumentation, which is generally the last to be installed and checked, with the construction contractor in preparation for actual process start-up. The start-up team usually consists of process engineers, lead opera- tors, operations specialists in start-up and training, and supervisory and maintenance personnel for mechan- ical, electrical, and instrumentation systems, as required.

Once the contractor and start-up team agree that the process is ready to run, the start-up supervisor pre- pares a detailed plan for putting the process into operation. Some of this plan can be prepared prior to the on-site start-up, but it must include detailed instructions concerning set points, valve settings, sampling, analyses, expected performance, and potential signs of trouble. An example of such a start-up procedure is shown in Table 1.42. One other important item that should be taken care of at this point is the ordering of any special tools, chemicals, or equipment that may be needed during the start-up. This will avoid embar- rassing delays if key items are difficult or time-consuming to obtain.

The equipment checkout activity itself involves operating the entire process as a unit on an intermittent or trial basis. For example, clean water might be used for checkout of a wastewater treatment system. This pe- riod should also be used to calibrate all instruments and metering equipment. Calibration curves should be developed where appropriate, and on-line testing of all monitoring equipment should be conducted.

The time required for this activity varies widely according to the complexity of the process, the compe- tence of the construction contractor, and the adequacy of the design. However, a typical range of periods re- quired for most pollution control systems is three days to two weeks. Continuous or long-term operation of the facilities on the material to be treated (gas, liquid, or solid) should not be initiated until the operations supervisor indicates that the process as a whole is safe to put in operation.

Process Start-up

Process start-up on the actual material to be treated is initiated upon instructions from the start-up supervi- sor according to the detailed start-up plan. This period generally demands considerable time and extra effort by the start-up team, including round-the-clock coverage for critical aspects of some continuous processes. Experience and skill are also needed to make “on the run” decisions.

Key items that enhance the prospects for a successful start-up include a good start-up plan, well-briefed operators, availability of skilled maintenance personnel (particularly for instrumentation and mechanical equipment), and a detailed knowledge of the process in order to solve nonequipment, i.e., process, problems that arise. Process start-up generally proceeds rather rapidly once everything is ready. Most pollution control processes can be started up in one to two days if no major failures occur. However, achieving steady-state operation often requires considerably more time.

Steady-State Operation

Establishing the steady-state operation of a process where the operators are truly in command of the system is the goal of all start-up activities. The time required to achieve that goal can vary widely, ranging from a TABLE 1.42 Excerpt from a Start-up Procedure for a Sludge Belt Filter Press

Step sequence Information and details

1. Set HAND-AUTO switch to HAND Located on control panel. 2. Lock the belt tracking switches ON Located on control panel 3. Lock the tracking alarm switch to Located on control panel

ALARM-SHUTDOWN

4. Prepare conditioning solution Prepare proper dilution of sludge conditioning agent 5. Switch components ON in the following order: Located on control panel

a. Drive b. Spray water c. Filtrate pump d. Fan e. Conveyors f. Polymer pump g. Sludge pump

6. Adjust pressure roller See Section 3.10.1 of manufacturer’s instructions 7. Observe belt steering under operating conditions See Section 3.10.1 of manufacturer’s instructions if

few hours for a process with a short turnaround time to several months for processes with long time con- stants such as biological wastewater treatment systems. In fact, “steady-state” is somewhat of a misnomer when applied to pollution control systems because they generally operate with minimal control over the in- fluent to the process. Therefore, transition from one state or operating point to another is the rule, and a steady state can be said to be achieved when the operators can make these transitions without a process up- set. It is the responsibility of the start-up team to explore various operating strategies and control points to identify successful process settings that can accommodate the normal variability in the input.

Achieving steady-state operation is to a large extent dependent on keeping and carefully reviewing oper- ating log sheets and performance data. One of the tasks of the start-up team during this period is to establish the sampling and analytical requirements necessary to control the process. The location, frequency, and type of samples required should be specified, and the types of analyses required on each sample must be noted.

A sample log sheet, including typical process operational parameters and sampling and analytical re- quirements for a wastewater treatment process, is shown in Table 1.43. In terms of establishing steady-state operation, this information can be used to evaluate the process, determine if it is performing as intended un- der various input conditions, and identify successful and unsuccessful operating conditions that have been employed.

Operator Training

Operator training can take several different forms and occurs at various times, including prior to start-up, during start-up, and following the establishment of steady-state operation. The type of training conducted is highly dependent on the background and experience of the operating staff to be trained. The range of capa- bilities and experience may be very broad, ranging from new-hires or trainees to highly experienced supervi- sors who need to review a new process or type of equipment. For this reason, every training program must be tailored to the needs of the process and the individuals who will be in the training sessions. However, there are some common areas that are generally covered in training courses for pollution control systems.

A typical course outline covering a broad range of topics and objectives is shown in Table 1.44. For any given training course, only portions of this curriculum might be used depending on the class needs.

Key elements that should be incorporated into a training program to make it successful are as follows: 앫 Pretest to identify students’ needs and choose the areas for emphasis in the course.

앫 Operators (not engineers or scientists) should train the operators.

앫 Make a few key points; be sure they are understood; do not present too much. 앫 Use example problems freely; develop them from the actual facility data if possible. 앫 Combine classroom and on-the-job training to broaden trainees’ experience.

앫 Posttest to evaluate the training, the instructor, and to determine how much progress was made.

Recent surveys have shown that one of the most widespread, significant deficiencies of operators in the pollution control field is the lack of basic process understanding. Therefore, the training should include what a given unit process is intended to do, how it does it, and how to control it when it is in operation. Far fewer deficiencies normally exist in knowledge of mechanical equipment and maintenance than in process control and operating strategies.

Operation and Maintenance Manual

An operations and maintenance (O&M) manual should be a well-worn reference document used by the op- erators for a variety of day-to-day operations needs. Detailed, valve-by-valve reference manuals cover every aspect of the system. All are useful documents if they meet their objectives, but one must be careful not to

TABLE 1.43 Sample Operating Data Log

1 2 3 4 5 6

pH Alum Poly Recycle Rise Anti-

Flow, pH, chart, rate, TSS, rate, rate, rate, foam, H3PO4, TSS, TOC, COD, BOD5,

Date mgd units units % mg/L % gpm s % % mg/L mg/L mg/L mg/L

1 2 3 4 5 6 7 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 Remarks (continues)

TABLE 1.43 Sample Operating Data Log (continued)

7 8 9

O2 Poly Sludge Recycle Recycle Waste

MLSS, MLVSS, pH, Uptake, ZSV, SVI, rate %, depth, rate, conc., sludge,

mg/L % units mg/L·min ft/hr mg/g % gpm gpm mg/L gal

10 Discharge

TSS, TOC, COD, BOD5, pH, Phenol, Flow, Temp, Cl2, pH,

Date mg/L mg/L mg/L mg/L units mg/L mgd °C mg/L units

1 2 3 4 5 6 7 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 Remarks

prepare the wrong type of manual for a particular application. Supervisors, operators, and maintenance per- sonnel need different types of information, and it is not always productive to package it all in a single docu- ment.

A comprehensive outline for an O&M manual for a wastewater treatment facility is shown in Table 1.45. This includes all of the necessary elements for most O&M manuals and can be used as a reference to choose sections that might be suitable for a particular application.

A critical aspect of the utility of any O&M manual is that it be written for operators, not engineers, in op- erators’ language, preferably by an experienced operator. This will make the document much more useful in the field and more widely accepted by the operators. Also, graphical presentation of information is often more valuable and useful than narrative or tabular information. Finally, it is generally a good idea to bind an O&M manual in a loose-leaf binder to facilitate updating of the manual, thus making it more of a working document and easier to copy for use in the field.

Periodic Operations Reviews

Once a process is in operation and achieving good steady-state performance, one of the most useful opera- tions assistance techniques is to conduct a monthly (or other selected time period) review of the performance of the facility. This review should be done by someone not involved in the day-to-day operation or supervi- sion of that facility and should include a discussion of any problems (process or equipment) encountered, so- lutions to those problems, review of operating data, adjustment of operating strategy, and identification of any system design modifications that may be required.

TABLE 1.44 Sample Training Program Curriculum for a Wastewater Facility 1. Introduction and pretest

2. Chemistry and biology Specific to waste treatment operations

3. Wastewater characteristics Solids, COD, BOD, dissolved oxygen, temperature, pH 4. Wastewater terminology Definition of key vocabulary items

5. Wastewater calculations Basic mathematics for treatment plant operators

6. Pretreatment processes Theory, instrumentation, operating procedures, hands-on operation of equipment

7. Chemical addition and precipitation pH control, use of polymers, dosages, calculations, operating procedures; hands-on operation of equipment 8. Principles of clarification Theory and practical application, calculations; hands-on

operation of equipment 9. Equalization Theory and practical application

10. Activated sludge Theory and biology of activated sludge, control; calculations, field examination of process

11. Final clarification Theory and principles of control, operation of related equipment, hands-on operation

12. Sludge digestion Theory and practical application, control calculations, hands-on operation of equipment

13. Sludge removal Theory of operation of sludge lagoons and drying beds 14. Operation of mechanical equipment Troubleshooting of equipment, pumps, agitators, instruments,

valves, and motors, principles of lubrication

15. Sampling and analytical techniques Proper sampling techniques, demonstration of jar test, pH test, DO measurement, calibration of all lab instrumentation 16. Data Collection, interpretation, and use of data, problems in

diagnosing plant conditions through use of data 17. Summary and posttest Review of any areas where questions exist, reexamination

These reviews are an excellent way to short circuit any minor nuisances before they become major prob- lems. The plant supervisor is afforded an opportunity to discuss strategies, performance, new technology, and other operations considerations on a fairly routine basis. This practice often results in improved overall operation and successful long-term performance.