Automation of Water Resource Recovery Facilities. Water Environment Federation

Digester Gas Withdrawal Control Strategies

       12.3.1 Process Description

       12.3.2 Process Variables

       12.3.3 Controlled Variables

       12.3.4 Control Strategies

       13.0 INCINERATION CONTROL

       13.1 Incineration Oxygen Control Strategies

       13.1.1 Multiple-Hearth Incinerators

       13.1.1.1 Process Description

       13.1.1.2 Process Variables

       13.1.1.3 Controlled Variables

       13.1.1.4 Control Strategies

       13.1.2 Fluid Bed Incinerators

       13.1.2.1 Process Description

       13.1.2.2 Process Variables

       13.1.2.3 Controlled Variables

       13.1.2.4 Control Strategies

       13.2 Incineration Temperature Control Strategies

       13.2.1 Multiple-Hearth Incinerators

       13.2.1.1 Process Description

       13.2.1.2 Process Variables

       13.2.1.3 Controlled Variables

       13.2.1.4 Control Strategies

       13.2.2 Fluid Bed Incinerators

       13.2.2.1 Process Description

       13.2.2.2 Process Variables

       13.2.2.3 Controlled Variables

       13.2.2.4 Control Strategies

       13.3 Incineration Pressure Control Strategies

       13.3.1 Process Description

       13.3.2 Process Variables

       13.3.3 Controlled Variables

       13.3.4 Control Strategies

       13.4 Offgas Wet Scrubber Control Strategies

       13.4.1 Process Description

       13.4.2 Process Variables

       13.4.3 Controlled Variables

       13.4.4 Control Strategies

       13.5 Flue Gas Carbon Feed and Baghouse Control Strategies

       13.5.1 Process Description

       13.5.2 Process Variables

       13.5.3 Controlled Variables

       13.5.4 Control Strategies

       13.6 Flue Gas Electrostatic Precipitator Control Strategies

       13.6.1 Process Description

       13.6.2 Process Variables

       13.6.3 Controlled Variables

       13.6.4 Control Strategies

       14.0 ENERGY MANAGEMENT STRATEGIES

       14.1 Real-Time Power Monitoring

       14.2 Controlling On-Peak Energy Demand

       14.3 Controlling Power Factor

       15.0 REFERENCES

       16.0 SUGGESTED READINGS

1.0 OBJECTIVE OF AUTOMATIC PROCESS CONTROL

      Process control is needed because various disturbances disrupt a process’s efficiency. Such disturbances include both known and unknown inputs and conditions (e.g., changing flows, chemical and biological compositions, temperature, and density). Process control devices (e.g., valves, flow meters, pumps, and other process equipment) can also introduce disturbances.

      Once a process is disturbed, compensation is required. Compensation can occur as part of a manual or automatic control system. Manual process control occurs when operators notice that a process variable has deviated from the desired setpoint and they manipulate a controlled variable (e.g., valve opening or pump