Another invisible issue is building code changes. “Plants think they’re OK, but they start adding square footage and you discover you now need sprinkler systems, fire walls, fire doors and more exits,” warns McNabb.
“The first thing is to assume that none of the drawings is correct,” warns Gerry Gomolka, vice president of process engineering at the Stellar Group (www.thestellargoup.com), Jacksonville, Fla. “Things either are not where they are indicated to be or there things that have been added that don’t even show up on the drawings.”
With 32 prior years as a plant engineer, Gomolka has seen a lot. He especially warns about underground utilities and systems. “A few years back I was participating in the renovation of a non-dairy plant and we kept discovering things underground. We had to find a retired plant engineer and have him walk us through the plant, marking things on the floor from his memory” – which was pretty good, Gomolka adds
Younger plants tend to make less complicated renovations.
“Most plants built in the last 10-15 years are of higher quality,” says John Schook, food and beverage manager at Carter & Burgess (www.c-b.com), a Fort Worth, Texas-based architecture and engineering firm. “They likely have pre-cast columns and pre-cast double Ts [in their roof systems]. You can make vertical drops into the process area with high ceilings -- process piping, electrical, etc.”
A good wastewater system and the ability to expand beyond the current plant constraints can be important features. Air units also can make a huge difference. These can be extremely heavy units that the existing plant structure may not be able to support if they have to be added during the project.
Often, poor initial design, failure to plan for future production, and the cumulative effect of short-term solutions make major plant projects far more difficult and costly than necessary. The consequences of failing to consider the interdependencies of a plant’s individual technological, mechanical, environmental, structural and human systems may take years to become clear. But the result of the quick fixes, Sander and Harmon say, can adversely affect plant quality and productivity and seriously impede plant expansion. They call this phenomenon “facility creep.”
The man with a plan
“I’ve built over 20 plants and managed a lot of expansions,” says another engineer from a leading food firm. “But we designed our plants to be expanded. From the time they were designed, we were anticipating adding lines, extending the plant. So our projects become more expansions than retrofits.”
And therein lies the key to a retrofit’s success -- planning. The planning that went into the last major plant design will determine the complexity and difficulty of the next upgrade. The plan for the upgrade likely will determine the quality and productivity that will flow from the plant. It will impact future expansions and renovations as well.
From the time a plant is built, it is undergoing change, evolving with market and production demands, aging, adapting to regulatory changes and corporate priorities. No change is an isolated event, but one of a continuous series of changes and decisions. Each decision ought to consider the cumulative changes in the plant right up to the present. Equipment and processing systems, the physical plant, operational systems, and employee traffic and habits all enter into a sound decision.
“The issue on renovation is ‘Do you have a facility that can continue to expand?’” says Hixson’s Harmon. “Your plan should unlock constraints that may have plagued the facility earlier. You try to get a plant that is more flexible and expandable than before.”
Plant designs have changed over the decades, in some segments quite dramatically.
“Meat plants built in the 1960s and ’70s differ dramatically from those built today,” says Sander. “A renovation on one of these plants generally requires refrigeration and air handling update, a change in floors and finished product and packaging areas.”
Dairy plants, too, have emphasized hygienic environment and absolute separation of raw and pasteurized product for years.
Sometimes processors take upgrades lightly and leave the details of execution to the contractor. Engineers universally decry this approach, and their position is not entirely self-serving.
“You want all the unknowns to be known before you go in,” says Schook of Carter & Burgess.
Planning should always start with the process.
“Identify all your needs for that process,” he says. “Raw materials processing, finished product packaging, people flows, trash flows, rework flows, etc. Understand everything in that plant and what it does.”
Analysis should include an exhaustive equipment list and documentation of that equipment and all its utility loads.
“Confirm that information. Cross-check all the equipment to existing utility capabilities and identify the shortfalls,” adds Schook. “Don’t make the mistake of calling a contractor in to start building a project. You have too many loose ends at this stage that can affect the overall design and utility systems and negatively affect your project.”
Design-build projects have flourished during the current fast-track era. But Schook says that he is seeing more design-led solutions these days in which owner and engineering firm help develop the criteria, drawings and construction documents. The owner bids the project based on the design.
“You don’t have so many cost overruns and utility systems that don’t meet needs,” he says. “Projects shouldn’t be rushed. There’s definitely a trend today toward engineered solutions.”