When evaluating the corrosive effects to floors resulting from industrial food processing operations, several factors come into play. First and foremost is chemical resistance. Food product production results in corrosive materials attacking the flooring on a regular basis. In the case of ice cream production, the corrosive material is lactic acid from milk products and from bacteria that potentially can—and will—exist. Mind you, this is only a small part of the chemical attack problem. Strong, sanitizing cleaners that are used to routinely clean processing equipment, storage tanks and other items that come in direct contact with food are potential hazards as well. These chemical cleaners typically include chlorinated cleaners, hydrogen peroxide, nitric and phosphoric acids, sodium hydroxide and other caustics. Combined with hot water, these chemicals can deteriorate many types of industrial flooring, such as seamless epoxy and brick/tile installation materials that are not high-performance.
How do the effects of food wastes, chemicals and hot water deteriorate an industrial floor? While food waste exposure to the floor may be small, bacterial growth is rapid and highly corrosive. The byproducts of bacteria, lactic and formic acids, are produced in high concentrations that can deteriorate many epoxy and other resin-type materials. In addition, sanitizing agents that are chloride and nitric acid-based will erode furan resin mortars and grouts, even in low concentrations.
Finally there are the effects that result from using hot water in cleaning. First, chemical cleaners are more corrosive at elevated temperatures than at ambient temperatures (I50°F vs 70°F). Second, thermal shock becomes a factor in the flooring's performance. All flooring materials expand or contract when subjected to wide temperature shifts. When large volumes of hot cleaning solutions are poured onto the cold floor, the floor temperature is raised rapidly and then cools down. Repeated cycling of heating/cooling (expansion/contraction) stresses the floor. This can ultimately cause failure, especially if movement joints aren't performing properly. Thermal shock is especially detrimental to thin (less than 0.25 inch, or 16 mm) epoxy coatings, which can delaminate or debond from the concrete substrate.
Another major factor in flooring performance involves traffic levels and types. Forklift trucks, heavy equipment, and steel wheeled carts constantly challenge flooring integrity. Generally, acid brick and industrial-thickness vitrified tiles (pavers) provide the highest level of performance against physical abuse. It is important for the grout joints to remain full and narrow, generally less than 5/16 inch. This reduces the potential for edge-chipping of the tile.
Floor performance is affected by job conditions and specific type of floor project. For new construction, sufficient curing time is necessary so that the floor will achieve proper strengths and levels of performance. However, job temperature is always a concern. Generally low temperatures decrease the installation materials' (adhesives, grout) rate of cure. As a result, supplemental heat sources occasionally must be provided. At the other extreme, hot temperatures increase rate of cure, but sometimes reduce workability and cause installation problems. It is important to select an experienced contractor who knows how to adjust for varying job conditions. Plant additions and repairs also provide a host of installation concerns. Most often, these types of installations require rapid "back-to-service" requirements. If the installation or repair hasn't achieved a proper cure, it will not perform to specifications.
Laticrete International has developed a range of industrial systems and products that have been specifically formulated to address such problems. These products have been used successfully at a number of ice cream plants and other food processing facilities around the world.
Walt Lafleur of Property Maintenance Contractors, Inc. has been directing service programs for several milk products facilities of HP Hood in Massachusetts and Connecticut. The ice cream plant in Suffield, Conn., had a brick floor with deteriorated grout joints. "If the grout continued to deteriorate below the brick, then the whole subfloor would be subject to failure and very expensive repairs," said Lafleur. Lafleur selected Laticrete's Latapoxy, a 100 percent-solids, high-performance epoxy grout that resists corrosives and thermal shock. Additionally, Latapoxy is fast-curing and highly water-cleanable when fresh, eliminating the need to pre-wax the brick before grouting. Because it has no appreciable odor, it can be used in an active food area without closing down nearby production-a very expensive and unwelcome portion of normal repairs. Lafleur selected a dustless mechanical saw system that made his preparation fast and easy. His contractors routed out the pitted and deteriorating grout, washed with a strong cleaner, flushed with water and then dried the joint before grouting. In areas where the substrate had deteriorated (normally around drains), he used Laticrete Rapid Repair mortars to replace concrete and re-set brick. Regrouting was accomplished, allowing for a 24-h cure, sufficient for floor temperature conditions on the job.
This procedure has also been successful at the Haagen Daz facility in Woodbridge, N.J., by T & E Meyle Industrial Contracting. Ted Meyle's firm specializes in the repair of brick and tile floors in eastern Pennsylvania and southern New Jersey. He has selected Laticrete materials because, "They are easy to use and set fast, and these are important properties for the 1,000-2,000-sq. ft tear-out and repair projects that my company does over weekends." Similar comments were voiced by John Muraldo of F & M Tile, Ft Wayne, Ind., whose firm recently completed a large repair at the Edy's Ice Cream plant in that city.
A major floor renovation of the Ben & Jerry's plant in Springfield, Vt. was done by Don-Vac of Burlington. This fast track, 12,000-sq. ft. project was to be done in three sections of the factory. An important reason for selecting acid brick and Latapoxy was to avoid any noxious odor that could affect workers or contaminate production. The current plant floor was a seamless epoxy installation, approximately seven years old, that had been patched in numerous areas and was having delamination problems. New drains were being incorporated into the flooring; therefore proper pitch of the new floor was critical.
The renovation project began with surface preparation. The seamless epoxy surface was mechanically scarified to remove contaminants. Loose and hollow sections were chopped out. A thorough wash (with strong detergent, not acid!) and rinse readied the surface for the Laticrete mortar bed. A Latapoxy bonding agent was used to prime the substrate prior to the application of the Laticrete latex-fortified mortar bed. (Laticrete mortars typically have a 200-300 percent higher compressive strength rating than conventional mortars; this is an important factor relative to the way a floor handles heavy traffic.) The next day, brick flooring was installed with a chemical-resistant Latapoxy adhesive.
Should all jobs involve an epoxy adhesive when a high-performance grout is being used? This question often balances on material cost relative to the expense of a premature shutdown or repair in the future. It's true that the front line of defense against chemical attack is the brick/tile surface and the grout. However, the ultimate material costs are relatively low to the total installation cost, and especially low when one considers the costs of shutdown or repairs in the future. Also, one cannot assume that corrosive chemicals will not get through (or around) this front line of defense. Tearouts or cracked joints permit chemicals to get beneath the brick or industrial tile.
By Michael Sawicki, Laticrete International, Inc.