Why save energy? Simple answer — it saves money.
Focusing on energy-efficient and substantial cost savings, key findings and recommendations from an energy assessment conducted at an asphalt terminal facility in New York was recently uncovered. Ultimately, the energy assessment revealed significant energy savings which can translate into huge cost benefits.
Energy efficiency and cost savings in asphalt facilities
Thermal imaging indicating heat loss from missing or crushed insulation.
The ability of an asphalt terminal facility to make money depends on two main factors: lowering energy costs and improving operations. With fuel prices constantly on the rise, asphalt producers are challenged more than ever to reduce operating and energy costs. So, how does an asphalt producer save energy? Where do we start?
The first question asphalt facility decision makers must ask is, "What is the least expensive form of energy for heating?" This is where heat-transfer experts can guide decision makers to make sound assessments for the long-term benefit of the facility.
This recent energy assessment uncovered potential savings of more than 1 trillion Btu over the next 10 years given how certain high-ROI projects are executed. To have the largest savings possible, a new heat recovery steam generator (HRSG) was recommended, which would be fully dedicated to making steam that heats rail cars and any other steam user in the facility. With this change, two of the three existing hot oil heaters can be idled. This change would result in substantial annual energy cost savings and would save energy in three different ways:
First, the asphalt facility’s heating system was initially set up to run three hot oil heaters. The majority of the heater capacity was dedicated to transferring heat from hot oil to the steam boiler for steam generation, thereby classifying steam as a tertiary energy source. The overall efficiency of the system was only 64% calculated as the product of the hot oil heater’s 80% efficiency and the oil-to-steam heat exchanger’s 80% efficiency. By removing the hot oil heaters and making steam directly in an HRSG from natural gas, the system would become greater than 85% efficient — Btu-to-Btu.
Second, electrical energy would be saved by turning off two of the three hot oil heaters. A single high-pressure pump running 24/7, 365 days per year uses about 130,000 kW of power. This change would save the facility almost 1 million Btu/yr of power or about $45,000 annually and would save the world 20 million Btu/yr over 10 years.
Third, converting to newer steam and addressing any steam leak as part of the change would save the plant almost $180,000 annually. Steam leaks, even small ones, are surprisingly low-lying fruit when it comes to saving energy. The DOE estimates that each steam leak costs about $6,000 in energy waste per year. Additionally, by minimizing steam leaks, the asphalt facility can reduce the loss of condensate, eliminating the need for excessive make-up water to maintain a fully operational closed-loop boiler system.
Other findings conducted during the energy assessment:
- Converting tanks from steam to hot oil heating is highly recommended. Hot oil heats tanks faster and reduces energy loss from steam leaks and traps.
- Minimizing steam consumption, such as addressing steam leaks and reconsidering the need to leave steam valves open year-round, is advised. Fixing leaks would also save a calculated 300 gallons per hour of make-up water.
- Insulating exposed piping and equipment is essential for safety, process stability and energy conservation. The report suggested insulating gate valves, asphalt-storage tank manways and steam tracing areas to prevent energy loss.
- Using steam tracing for asphalt piping, where applicable, is recommended, as well as enhancements like aluminum tracing for better performance. Electric tracing, though easier to install, is not suitable for asphalt lines due to its limited heat-up capability.
- Operating pumps efficiently in such facilities will minimize energy usage since they are a major energy consumer.
Through these recommendations, other facilities can achieve similar results, including enhanced operational efficiency, reduced energy costs and environmental sustainability. Finding solutions to meet current energy challenges is not only possible but can pave the way for a more sustainable future.
For more information, visit qmaxindustries.com.
