How can hot air circulation technology be used to reduce energy consumption and carbon emissions during the production of PE recycled pellets?
Release Time : 2026-01-26
In the production of PE recycled pellets, hot air circulation technology has become a key means of reducing energy consumption and carbon emissions by optimizing thermal energy utilization efficiency and reducing energy waste. Its core logic lies in recovering, redistributing, and recycling waste heat generated in the production process, forming a closed-loop thermal energy management system. This reduces dependence on external energy sources and simultaneously lowers greenhouse gas emissions. This technology is applied throughout key processes such as raw material pretreatment, melt extrusion, and pelletizing. By precisely controlling the hot air temperature, flow rate, and circulation path, it achieves efficient energy conversion and cascaded utilization.
In the raw material pretreatment stage, hot air circulation technology dries waste PE plastic by heating air, removing surface moisture and impurities. Traditional drying methods often rely on direct heating, resulting in low thermal energy utilization and a tendency for localized overheating, leading to a decline in raw material performance. The hot air circulation system, however, uses closed pipes to evenly deliver heated air to the drying chamber, creating a stable airflow field that ensures uniform heating of the raw material. Simultaneously, the system can recover the humid and hot air discharged during the drying process, dehumidify it, and reheat it for reuse, significantly reducing the energy consumption required for heating fresh air. This process not only reduces carbon emissions but also avoids subsequent processing defects caused by fluctuations in raw material moisture content.
Melted extrusion is the most energy-intensive stage in PE recycled pellet production. Traditional extruders maintain the melt temperature through electric or gas heating, resulting in significant heat loss and low temperature control precision. Hot air circulation technology constructs a hot air jacket outside the extruder, uniformly enveloping the barrel with high-temperature hot air to create a stable heat conduction environment. The hot air temperature can be adjusted in real time according to process requirements, avoiding energy waste caused by localized overheating or insufficient temperature. Furthermore, the system can recover waste heat discharged from the extruder; after cooling through a heat exchanger, part of it is returned to the heating system, and the remainder is used to preheat raw materials or auxiliary equipment, forming a multi-stage heat utilization chain to further reduce overall energy consumption.
In the pelletizing stage, hot air circulation technology reduces pellet adhesion and deformation by precisely controlling the pelletizing chamber temperature. In traditional pelletizing processes, the pelletizing chamber temperature fluctuates greatly, requiring continuous replenishment of heat energy to maintain processing stability, leading to increased energy consumption. The hot air circulation system, by arranging temperature sensors and hot air nozzles inside the pelletizing chamber, monitors and adjusts hot air flow and temperature in real time. This ensures that the pellets cool and solidify rapidly after leaving the die, preventing sticking or deformation due to excessive temperature. Simultaneously, the system recovers waste heat generated during pelleting to preheat the raw materials entering the pelletizer, forming an internal heat energy circulation and reducing external energy input.
The energy-saving effect of hot air circulation technology is also reflected in equipment maintenance and operational optimization. Traditional heating systems are prone to equipment aging due to localized overheating, requiring frequent replacement of heating elements, increasing maintenance costs and energy consumption. The hot air circulation system, by evenly distributing heat energy, reduces localized temperature peaks in the equipment, extending its service life. Furthermore, the system is equipped with an intelligent control system that automatically adjusts hot air circulation parameters according to production load, preventing idling or overheating and further reducing standby energy consumption.
From a carbon emission perspective, hot air circulation technology directly reduces carbon dioxide emissions by reducing fossil fuel consumption. Traditional PE recycled pellet production relies on fossil fuels such as coal and natural gas, whose combustion processes produce large amounts of greenhouse gases. Hot air circulation systems indirectly reduce carbon intensity by improving thermal energy utilization efficiency and reducing energy consumption per unit of product. For example, in the melt extrusion stage, improved thermal energy utilization reduces fuel consumption, thereby lowering carbon dioxide emissions from combustion. Simultaneously, the system reduces external energy demand by recovering waste heat, further compressing carbon emission space.
The widespread adoption of hot air circulation technology also faces challenges in terms of technological adaptability and cost control. Different types of waste PE plastics exhibit significantly different melting characteristics, requiring customized design of hot air circulation parameters to ensure processing stability. Furthermore, initial equipment investment and retrofitting costs are high, necessitating cost amortization through large-scale application. However, with technological maturity and policy support, the economic and environmental benefits of hot air circulation technology in PE recycled pellet production are becoming increasingly prominent, making it an important direction for the industry's green transformation.
Hot air circulation technology provides a sustainable solution for PE recycled pellet production by optimizing thermal energy utilization efficiency and reducing energy waste and carbon emissions. Its application not only reduces production costs but also promotes the development of a circular economy for plastics towards low-carbon and high-efficiency directions. In the future, with technological iteration and policy guidance, hot air circulation technology is expected to be applied on a larger scale in the field of recycled plastics, contributing to global carbon emission reduction goals.