The basic maintenance operations that should be applied daily to all dry chemical feeders are as follows:

Clean the feeder, the feeder mechanism, and the feeder surroundings. Use a vacuum cleaner or brush to remove spilled chemicals or chemical dust. Make certain that the orifice, knife edges, scrapers, shakers, and openings are free of chemical accumulations in volummetric feeders, and that both belt rolls and belt, in belt- gravimetric feeders, are free of chemical accumulations.

NOTE When working with chemical dust, wear chemical goggles or a mask.

Check the feeder for general performance. Note and investigate unusual noises.

Observe the condition of electrical wiring, fuses, and connections

Check for oil drips and general deterioration,

Make necessary repairs to overcome deterioration and lack of good performance.

Wipe all parts of the feeder and inspect for loose bolts, cracks, defective parts, and leaks. Make the necessary repairs to eliminate undesirable conditions.

Check the solution tank for sediment or undissolved chemicals and remove accumulated material.

When the dissolver is lined with asphalt, check the lining, which should not be skinned away from the steel. Follow the manufacturer's instructions to repair such linings. Quarterly, service moving parts and lubricate, following the manufacturer's instructions.

The maintenance operation frequency and schedule of inspections for dry chemical feeders are shown in appendix III, table B

SOLUTION FEEDERS

Maintenance procedures for pot-type solution feeders include the following:

Daily operator inspection which includes observations of the amount of chemical feed to determine whether flow through the post is effective.

Monthly cleaning of the sediment trap and check of the valve.

Cleaning of the chemical pot and orifice every 6 months.

Annual overhaul that includes cleaning and painting the pot feeder and accessories.

With the decanter or swing-pipe feeder, the swing pipe should be checked monthly. The reducing gears, pawl, ratchet, and motor should be checked semiannually and overhauled annually, or as necessary. Overhauling includes cleaning, repairing, and painting all parts that require attention.

The maintenance operation frequency and schedules of inspection for liquid and solution chemical feeders are shown in appendix III, table C.

Q5. What personal safety equipment should you use when working with dry chemical feeders and chemical dust?

Q6. Moving parts and lubrication of a dry chemical feeder should by done at what intervals?

Q7. Overhauling a solution-feed chlorinator includes what three operations?

MAINTENANCE OF ION-EXCHANGE UNITS

LEARNING OBJECTIVE: Identify and understand basic maintenance requirements for Ion-exchange units and equipment.

An ion-exchange unit is shown in figure 8-4. Some of the maintenance procedures for this type of unit are given in the following sections.

SOFTENER UNIT

The softener unit itself consists of a steel shell, containing a supporting grid in the bottom, a layer of gravel, and a layer of ion-exchange resin. The shell is equipped with openings, valves, and fittings. Maintenance procedures for the unit are as follows:

Annually, the exterior of the shell should be cleaned and brushed with a wire brush and then painted to protect it against corrosion.

Quarterly, the fittings for the distribution of water and brine should be checked for possible obstructions, corrosion, and security fastness. 8-5