For industries that rely on steam as an integral part of their processes, more hp is not always needed to meet increased demand - even when existing boiler capacity just can’t keep up. A perfect example is Turtle Island Foods, Inc. of Hood River, OR, which is known for its vegetarian product, Tofurky.
From the outset, they used steam-jacketed kettles to produce their original product, tempeh. So steam has always been an integral part of their process. Steam production increased with the company’s growth. They started with a 9.5-hp, bent-tube atmospheric boiler then added another 9.5-hp bent-tube boiler. A little later, they added a 25-hp bent-tube and ultimately, a 50-hp unit in addition to that.
Starving For Steam“We were starving for steam,” said Jaime Athos, operations manager of Turtle Island Foods. “The Tofurky is all cooked in steam ovens or houses. And we were finding that though we have four steam houses in our plant, we were actually limited to running only two of those at the same time. Our existing boiler capacity just could not keep up with the steam demands.”
“Plus, we have a clean-in-place (CIP) system that requires quite a bit of steam power because you’re heating up a large volume of water with sanitizing solution in it and circulating that throughout long pipes that run throughout the plant. It definitely puts a demand on our steam system,” Athos said.
Corporate Culture ConsideredThe effect of the boiler on the environment was another factor when the decision to increase capacity was made. As Athos put it, “Concern for the environment is sort of who we are as a company.” The company’s culture is committed to environmental causes. All of their electricity is purchased through wind power programs, for example.
Fitting nicely with their concerns is the state of Oregon’s business energy tax credits program that works as an incentive to businesses to purchase energy-efficient equipment. As Athos described it, “That helps us to recoup our investment in steam production, as well. You can take that incentive in one of two ways. You can either take it as a tax credit that is distributed over five years or they also have a trading arrangement that they call a ‘pass through partnership.’ It allows a business to basically buy those tax credits from you by paying you a check - just one lump sum.” Atmospheric-style boilers weren’t eligible for the tax credit.
Turtle Island weighed several factors during its boiler investigation. One was the recovery time. That was pretty critical for because of the up and down nature of the demands on the plant’s system. Another one was energy efficiency. Athos explained, “As a growing company it is easy to just add more and more capacity in an inefficient way. But in terms of our goals, it makes a lot of sense to think long term. You pay a little bit more up front and recover that additional initial investment over the long term. The environmental effects were another major consideration.”
Turtle Island Foods had two options - add another boiler to increase capacity beyond 95 hp or replace all the boilers with a different kind of steam-producing technology that would basically have the same capacity.
The company’s management ended up selecting Miura Boiler, Inc., which has developed boilers that can be turned on and off like light bulbs so they are always operating at peak efficiency for energy savings and quick response to fluctuating demand. The company’s straight watertube, low NOx boilers are designed for steam starved, volatile demand processes.
22.9% Fuel SavingsAfter replacing their old boilers with a Miura LX100 hp, Athos saw a sizable drop in Turtle Island’s energy usage. From November 2004 to November 2005, the plant produced 45.6% more product. In that period, the price of natural gas went up 25%. To their great relief, due to the in-service efficiency of the new boiler, the increase in their gas usage was only 12.2%. So, they increased their productivity per therm by 29.8% and decreased their natural gas usage on a per-pound-of-product basis by 22.9%.
“As natural gas prices increase, the return on our investment won’t be long in coming,” Athos added.