Case Study

The Use of Solid-Concentrates

For

Boiler Water Treatment

Midwest Facility

3-1-02

SCOPE:

This is a case study of boiler water chemical treatment at a Midwest Food Plant, utilizing SOLID-CONCENTRATES. Solid-Concentrates are a relatively new development in the water treatment industry, utilizing existing technology but providing it in a form that is safer to handle and use. United Supply Service, Inc. distributes solid-concentrate products and a dispensing system to replace liquids while still maintaining the integrity of existing water treatment programs.

BENEFITS

Eliminate chemical drum handling, lifting, disposal
Eliminate containment areas, spill, and exposure issues
Space saving wall-mounted automatic dispensing system
Continued utilization of existing bleed and feed equipment
Reduced shipping costs
Reduced inventory costs
No freezing considerations
Usage costs are the same as liquids

A complete line of products has been developed in solid-concentrate form. The chemistry of these products has been designed to correct most types of water problems, at varying ranges of hardness, pH, alkalinity, etc. United Supply Service, Inc. distributes a unique Dispenser/Dissolver. The plant’s existing pumps and feed equipment can still be used.

OPERATION

Product is provided in 4x1 gallon plastic containers (44-50 pounds/case). Generally, one case of Solid-Concentrate is equivalent to between 30-55 gallons of a liquid product. The Dissolving Unit is 24 in x 24 in and weighs 23 lbs; it is attached to a wall, connected to (A) An incoming water line and (D) an outgoing line connected to the existing feed equipment, and plugged into a 110 V outlet (for safety, all voltage is reduced to 24 volts). The plastic gallon container is then positioned into the Dissolving Unit (B). As the system calls for treatment, the reservoir in the Dissolving Unit empties. A lower level switch activates/opens a solenoid valve and incoming water dissolves a portion of the solid concentrate and begins to refill the reservoir until an upper level sensor deactivates/closes the solenoid valve. This action continues intermittently (whenever the system calls for treatment) until the one-gallon container is completely empty. The operator then replaces the empty container with a full unit and the empty container can simply be disposed. System monitoring, by means of testing, continues as it always has.

History:

Prior to the construction of a new utility plant in 2000, the Operation had been utilizing liquid chemical treatment of their water systems. This involved handling 30, 55, and 250-gallon containers. Product was transferred (mixed) into day tanks and pumped into the water system that was being treated.

Operating Parameters:

2 Nebraska water tube boilers
Steam produced/hour: 50,000 lbs
Operating Pressure: 160 psi
% Condensate returned: 50%
Boiler Water Cycles: 15 – 20
Water Source: softened make-up,

PROPOSAL:

Solid-Concentrates were introduced to the plant almost three years ago, in order to replace liquids without sacrificing the level of control that the plant was experiencing by using liquid chemicals. The new program was focused on establishing the following goals:

Maintain the same or better level of system cleanliness
Eliminate chemical drum handling/disposal
Space saving
Reduced inventory
Reduce costs and environmental concerns of containment areas
Accomplishment of all of the above without incurring increased costs

THE PROGRAM:

The system was put into operation during the summer of 2000. Solid-Concentrate feed was set up separately, in order to control the following:

Oxygen Scavenger…. boiler water treatment B-S-C Solid-Concentrate

Sludge/Scale/Corrosion Inhibitor…boiler water treatment B301-C Solid-Concentrate

Condensate Corrosion Inhibitor…condensate treatment NAD-1 Amine*

*Since the plant feeds amine directly into the steam header, it was agreed that they would continue with the FDA approved liquid product. The Solid-Concentrate amine contains an inert substance, which, although it is a food grade approved product-in fact, it is an ingredient in some soft drinks, is not approved under Title 21, Section 173.310.

RESULTS:

The system was recently opened for inspection and the results were spectacular. Both boilers were absolutely free of any scale/sludge and the passivated metal had no evidence of any oxygen pitting.

The heaviest container that an operator must handle is a 50 lb case.

We were able to effectively eliminate all liquids, except for the amine, and reduced the space for drum storage by at least 75%.

There is no container disposal necessary, except for the 5-gallon pails of liquid amine.

2001 cost for boiler treatment was $13,200. Liquids prior to this time were averaging about $15,000 per year. This results in a net savings of 12 %. The dissolving equipment cost about $1,200 so there is less than a year’s payback on the equipment.