By Charles Stark, Wilmer Pacheco and Adam Fahrenholz
The word sustainability has been an evolving term in the feed industry. Looking back in the Feed Manufacturing Technology V book the word doesn’t even appear in the index, but the feed industry has been talking about it for over 25 years. To some it may mean just trying to stay in business while for others it may be a new way of doing business.
Sustainability is defined in Wikipedia as “the capacity to endure in a relatively ongoing way across various domains of life. In the 21st century, it refers generally to the capacity for Earth's biosphere and human civilization to co-exist.” The definition seems to be aligned with the discussions taking place in society that are centered around climate change and carbon emissions, mainly in the form of carbon dioxide (CO2). While there are many reasons why the climate is changing, the facts are that the world temperature is rising, glaciers are melting, air and soil temperatures are rising, and carbon emissions are increasing.
The 26th United Nation's Climate Change conference is focused on having both private and corporate companies pledge to be Net Zero CO2 by 2050. Companies worldwide are committing billions of dollars to reduce or offset carbon emissions by being more efficient, investing in new technology or projects that offset carbon emissions. New technologies are targeting the removal of CO2 from the atmosphere and putting carbon back into the ground in an effort to reduce the total carbon in the earth’s atmosphere. As companies or individuals, investing in green energy (solar, wind, hydroelectric), are longer term solutions. However, there are also short term solutions, such as reducing energy usage and waste that will help the environment and improve the bottom line.
The challenge of reducing or eliminating carbon emissions may seem overwhelming but the reality is that all feed mills have an opportunity to reduce energy usage and carbon emissions, and some have already started the process. Students come back from internships and talk about doing Waste Walks where they look for waste in the feed mill. Waste can take different forms from paper bags, rework, spilled ingredients or feed, and shrink. Basically, look in the trash dumpster or the warehouse and you will find a significant portion of the potential waste that can be reduced.
Reducing energy usage in the light of rising energy costs will be a major focus for most feed mills since electrical energy, boiler fuel, and vehicle fuel make up a significant cost portion of the manufacturing and delivery costs. Reducing energy costs will also reduce carbon emissions if the feed mill uses less carbon-based energy. The first step to reducing energy usage is to understand where the feed mill is using a significant amount of energy. Typically, we tend to look at the big motors in the feed mill (grinders, mixers, and pellet mills), but when you stop and look at any one of those motors there are a significant number of other motors associated with the process. For example, let’s consider the pellet mill motor. In addition to the main drive motor there are the feeder screw, conditioner, force feeder, cooler motors, fan, crumblaer, drag conveyors, and bucket elevators (Wow, that’s a lot of motors). For each of the motors are you using high efficiency motors? Are motors shut off when not in use? Are motors correctly sized for the equipment?
The generation of steam by the boiler could be the highest single cost in the feed mill depending on the fuel source. While the cost of the energy source is important, often it’s outside of the control of the manager. Consider developing budgets, goals and KPIs around BTU inputs per ton of feed. The efficiency of the steam system can be improved by the addition of stack economizers, blowdown heat recovery units, and total dissolved solids monitoring. However, many of these improvements require capital investment; therefore, look for short term solutions such as uninsulated pipes, steam traps that are stuck open, and pellet mill operation. For example, if the door between the conditioner and pellet die/roll chamber is open, steam is escaping which is an energy loss.
Delivery of feed requires a great deal of diesel fuel. The amount of fuel required to deliver 24 or 27 ton on a delivery will be similar. Therefore, check the weight of each feed load to ensure it is as close to the legal limit without going over. The selection of equipment may depend on customer requirements or the design of the farms in the case of integrated operations, but once again there are opportunities for reducing the weight of the equipment. Oil heat exchangers, super singles, and smaller fuel tanks will reduce the unit weight and increase the amount of feed hauled. Working with customers to optimize the delivery of feed to one site and making sure that every load is full will reduce the delivery cost per ton.
Energy used for lights and HVAC may not be a significant portion of the electric bill but every little bit helps. Installing LED bulbs and motion sensors throughout the facility are relatively simple. Check that the HVAC units get properly serviced on a regular basis especially in dusty locations. Determine the SEER rating on your HVAC unit, the minimum rating for new units is now 15 with the average being 25 and the most efficient being 35. While a SEER 35 unit may not have a great ROI currently, it may in the near future.
Conserving energy and lowering carbon emissions in your facility is not something that will happen overnight in facilities, but now is a good time to start having those discussions with employees, customers, and the communities you call home. Customers may have a greater appreciation for what you are trying to do than you expected. Create a team, give them some funds and you may be amazed with the creativity they have for helping Mother Nature and future generations.