Center Ethanol plant finds efficiencies
It is no secret that U.S. ethanol feedstock prices and production have taken a hit over the past few years. Many start-up companies, once buoyed by the promise of the Energy Independence and Security Act (H.R. 6), which calls for 36 billion gallons of renewable fuels by 2022, have closed their doors.
However, according to Tim Kostecki, operations manager at the Center Ethanol plant in Sauget, Ill., the secret to surviving in this down market is not really a secret. He says reliable investor support, negotiating supplier prices, and uncovering new production efficiencies are the reasons this 54-million-gallon-capacity plant thrives today.
Since production began over one year ago, Center Ethanol has continually enhanced its operation by adding programming to its Simatic PCS 7 process control system from Siemens Industry, Inc. Installed by Delta T Corporation, the PCS 7 system has performed reliably in the green-field project that also produces 172,000 tons of dry distiller grain annually.
As Siemens’ 100th alternative fuels plant installation in the U.S., Center Ethanol has been able to draw on much process know-how collected from all those facilities. Kostecki attributes much of the success to the flexibility of the PCS 7 system combined with Siemens’ feedstock technology expertise, which has helped in numerous areas of the continuous process plant.
Added programming increases efficiency
“We received the PCS 7 system in good shape. However, to run our processes more efficiently, we needed to be able to add a lot more programming into it,” Kostecki said. “It has been easy to introduce our ideas to improve the process.”
Center Ethanol built screens on the PCS 7 system outlining standard operating procedures for starting, stopping, and shutting down various pieces of equipment. It has also introduced programming that instructs operators how to fix out-of-range process parameters. “If a process goes out of parameter, an alarm alerts technicians in a central control room that is equipped with four operator stations,” Kostecki said. “The operators can check the equipment or cross-check what the equipment is telling us against what the lab is telling us. This has greatly improved temperature, pressure, and many other control variables.”
Faceplate and interlock screens enable operators to click on a symbol—including a pump, drive, valve, or PID loop—to determine the status of the device and process interlocks. Operators also have a comprehensive view of the entire plant from the control room and are able to drill down to a specific process area or to a specific device to get more information. Center Ethanol also added programming to better control enzyme and chemical additions as well as the front end (core grinding and fermentation) of the process.
Kostecki notes, “We are now saving more money than before because we can optimize chemical additions to the process. We have also done a lot with improving the front end of our process efficiency, so the entire plant is in a steadier state, instead of up and down. The new programming ensures that we start off with the right recipe for fermentation. When you control your front end and get your fermentation in a steady state, the whole plant runs more efficiently. If you are going up and down all the time—say one fermentor is at 14% and one is at 13%—it will swing the distillation of the back end of the plant around, so you cannot get your fermentation to be the same ethanol concentration every time.”
Trending and training
Kostecki appreciates the trending capability of the control system, because it can instantly give operators at least three months of historical data that can be loaded into an Excel spreadsheet, eliminating the need for time-consuming manual data entries. “We use trending every day,” he says. “For example, we know if our system is running out of tank room. Rather than slowing down the plant, the guys in the control room can graphically track and manipulate tiny changes in tank levels. We also use the trending capability to make sure dryer temperatures, pressures, flow rates, and amps are at the right levels.”
Center Ethanol has an extra advantage when it comes to attracting operators and other plant personnel. Many of its technicians were trained at another Siemens installation—the National Corn to Ethanol Research Center (NCERC) at Southern Illinois University, Edwardsville, Ill. The 35,000-sq-ft NCERC facilitates the commercialization of new technologies for producing ethanol more effectively, resulting in improved yields and reduced costs. It also plays a key role in filling the growing need for qualified personnel to operate and manage biofuel refineries across the country.
Today, Kostecki says the PCS 7 system can accommodate more programming additions if they are needed, and he has more in mind. Center Ethanol is now considering adding APC (advanced process control) capabilities to the system to save plant energy costs. “The employees like the system and say it is well designed,” he said. “Information flows from screen to screen and is easy to understand. It is also easy to comprehend how the different characteristics of the process are controlled. Just as important, however, is the fact that the PCS 7 system increases our ability to improve the system through new ideas. The capabilities of the system are not being fully used right now, which is nice because it means we can tweak things as we go, like advanced process control. This all fits well with our recipe for success, which is to be as innovative and efficient as possible.”
Rich Chmielewski is chemical and biofuels marketing manager for Siemens Industry, Inc.