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CHAPTER 15

CHEMICALS AND

CHEMICAL HANDLING

Jerry L. Anderson, P.E.
CH2M HILL
Louisville, Kentucky

A principal issue in modern water treatment plant design is the decision of what chemi-
cals are to be used for treatment processes, how they are to be shipped and stored, and
what type of chemical feed equipment should be used. This chapter summarizes alterna-
tives and issues associated with gaseous, dry, and liquid chemicals and the associated
equipment and piping necessary for their use. Other issues for the designer to consider
involve the many regulations that must be met and safety considerations in planning the
chemical feed systems. Finally, the importance of securing and hardening of chemical
handling facilities is a part of modern design.
Additional discussions of the theory of chemical treatment may be found in detail in
Water Quality and Treatment. Details of specific chemicals commonly used in water treat-
ment processes are provided in Appendix A.

RECEIVING AND STORING PROCESS CHEMICALS
Many alternatives are available for receiving and storing process chemicals, depending
on plant size and location, treatment processes to be used, and many other factors.

Sizing Storage and Feed Systems
Sizing of storage and feed systems begins with an investigation of dosage requirements
for each chemical used. Chemical feed rates (lb/day, ft3/h, gal/day, kg/day, etc.) can be
computed from dosages (mg/L) and plant flow rates [million gallons per day (mgd), ML
per day]. For chemicals in dry form:
Feed rate (lb/day) = 8.34 lb/gal × dosage (mg/L) x flow (mgd)

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