In this post, Glen Corley, Air Handling Filed Performance Test Manager, shares strategies for pulp & paper mills to drive efficiencies and reduce emissions.
Industrial fans consume a lot of energy. ProcessBarron has been an innovator in fan efficiency from the beginning. One of our founders, Bob Perry, had insights in the 80s and 90s that helped take some client’s fans from a 30% efficient fan to a 70% or greater fan system efficiency. But as dramatic as those improvements were, many clients didn’t prioritize efficiency because power was cheap. Industrial customers could get electricity for approximately $0.03 per kilowatt hour in the early development of fan efficiency improvements, so the ROI wasn’t there. But now that industrial consumer’s electricity rates are $0.08 to $0.10 or more, fan efficiency is a hot topic.
The potential cost savings based on current energy prices means everyone has incentives to increase efficiency by reducing energy consumption. One of the best ways to improve system efficiency is to establish baselines and KPIs for system performance. Let’s look at factors that affect fan system efficiency and strategies to reduce costs and improve performance.
Factors that Can Impact Fan System Efficiency
Many factors affect fan system efficiency. Sometimes, the fan can even be the bottleneck that limits production, and that’s a big deal. That is when the real cost of fan inefficiency starts to skyrocket. Factors that affect fan system efficiency include:
- Poor design – If the fan was not properly sized based on your plant’s system needs or didn’t go through the proper testing and quality checks, it has likely underperformed from day one. This problem many times originates from too many companies getting involved in the design phase of the fan selection with each company involved adding excess safety factors into their recommendations. This creates duplication of safety factors which in turn leads to a fan being over designed for the required system demand.
- System changes – Your system may not need as much fan capacity as it did in the past due to lower system resistance. This is a source of major fan system inefficiency. This causes the fan to operation on a different system resistance curve for which it was originally designed. Fan system efficiency as low as 6% has been measured under this condition. There are also opportunities for efficiency gains for a system whose operating needs have increased and therefore requires additional fan capacity. In this scenario, the loss for the plant would be due to limited production output capacity resulting from fan limitations which can be very costly. These conditions offer an excellent opportunity for the plants to reduce the fan’s operating cost and associated carbon footprint.
- System leakage – When system air in-leakage occurs, fans must work much harder to overcome the leakage, which introduces all kinds of inefficiencies. Some examples include increased fan motor power consumption, reduced thermal heat transfer (air heaters), increased duct corrosion from ambient air infiltration, etc.
Here are five more factors impacting your pulp and paper mill’s bottom line.
The Right Way To Measure Industrial Fan System Performance
Most of the time, when plants reach out to us, they know they have a problem with their existing fans but haven’t pinpointed the root cause. They call ProcessBarron because our expertise as a total system solutions provider sets us apart. Fan system problems are frequently caused by factors outside the fan. Our expertise in the total system helps us anticipate what will happen when a fan’s operating parameters change so we can identify the real root cause of the problem. Most of our competition focuses on specific components in the system, so it’s difficult for them to see the big picture when the underlying problem lies outside their area of expertise.
Process Barron’s approach to assisting our customers with fan system problems is to not only look at how a fan system is performing but also look at the system components before and after the fan to identify if there is a problem with the fan or if there are other contributing factors in the system causing the fan to underperform to ensure we recommend the right solution.
It’s important to consider what you measure and where you measure it. We look at several factors throughout the system to identify:
- Abnormal energy usage
- Air-in leakage
- Pressure changes
- Restricted flow
- Fans with dampers closed to less than 50%
This helps us pinpoint the problem and quantify the inefficiency, including what it costs the plant. And the savings from improving efficiency add up. For example, we worked with a paper mill that had a 15% leakage in its system, costing the plant $200,000 extra a year in fan motor capacity to overcome that leakage.
Our Industrial Efficiency Program (IEP) has several benefits for pulp and paper mills. Read more about these benefits.
Establishing a Baseline
I’ve conducted these tests on fans and fan systems for 30 years, normally testing over 100 fan systems each year. Unfortunately, we usually only get calls for field performance testing once the problems have already appeared. I believe one of the best investments a plant can make is to establish a baseline test of the fan and system when they are operating at peak performance. The most opportune time to do this is right after the yearly scheduled maintenance outage. When this test data is identified and documented, we understand what the optimal system performance looks like. Then we can test the system and quickly identify what has changed when problems arise.
It’s tempting to put off fan and system testing when the system is working well. But establishing a baseline saves money in the long run because it equips the facility to diagnose problems quickly and accurately when issues arise. The ROI is there in the long run.
We spend most of our time working with engineers and maintenance managers focused on putting out fires and keeping production online. All plants have key performance indicators, but they don’t always have them identified specifically around industrial efficiency and fan system performance. We work with these clients to help them develop key indicators that pinpoint factors that can help anticipate inefficiency and solve problems before they cause unplanned downtime. An effective KPI plan includes measuring factors like fan impeller wear as a part of your annual maintenance plan. You should monitor other metrics continuously or on a routine basis. This strategy should be tailored to your plant, but you should track metrics like these at various points throughout your system.
- Velocity pressures
- Static pressures
- Barometric pressure
- Absolute pressure
- Gas temperatures
- Relative humidity
- O2 percentages
- Corresponding process activity
- Fan inlet damper positions
- Fan shaft/motor rotational speed
- Fan vibration
- Motor input power (ampere and voltage).
Understanding these KPIs will also help plants concentrate on the most valuable areas to spend their time during outage season.
Maximize Material Usage and Improve Throughput At Your Plant
Our expert onsite technical service solutions were developed with your needs in mind. We come to you with detailed inspection, testing, and analysis services that target your concerns and expand into comprehensive reviews of the total system. Our engineers and field test specialists have extensive knowledge and take the time to investigate potential causes throughout the production process. We assess your industrial fans and entire air handling systems to keep your plant up and running and provide data-based solutions focused on improving performance and reducing cost.
Contact our experts to learn more about developing custom efficiency KPIs for your plant!