Project Case of Dilute Phase Pneumatic Conveying of Plastic Pellets for a Plastic Enterprise in Tianjin

This article presents a detailed project case study of a dilute phase pneumatic conveying system designed and implemented for a plastics manufacturing company located in Tianjin, China. The system is specifically engineered for the gentle and efficient transport of plastic pellets, a critical process in modern plastic raw material handling. The project was executed by Shandong Headpowder Engineering Co., Ltd., a leading provider of pneumatic conveying solutions headquartered in Shandong, China. The core products involved in this project include plastic pellet dilute phase conveying, plastic raw material conveying, and dilute phase granular material conveying engineering. These technologies ensure that the client’s production line operates with minimal product degradation, low energy consumption, and high reliability.

Project Background and Client Requirements

The client, a well-established plastics processing factory in Tianjin, faced significant challenges in their existing material handling system. They required a reliable method to transport a variety of plastic pellets—including polyethylene (PE), polypropylene (PP), and ABS—from storage silos to multiple processing machines across a distance of approximately 150 meters. The original manual handling and mechanical conveyor systems caused frequent pellet breakage, high dust generation, and inconsistent feed rates. The client’s primary objectives were to achieve a dust-free, low-damage transport solution that could handle a throughput of 10 tons per hour while maintaining product quality. They specifically sought a system that utilized plastic pellet dilute phase conveying technology, as it offers the optimal balance between conveying speed and product integrity for non-abrasive granular materials.

Solution Overview: Dilute Phase Pneumatic Conveying System

To meet the client’s requirements, Shandong Headpowder Engineering Co., Ltd. proposed a customized dilute phase pneumatic conveying system. This system is designed to transport plastic pellets using a high-velocity air stream at relatively low pressure, ensuring that the particles remain suspended and separated throughout the pipeline. The plastic raw material conveying process begins with a rotary airlock feeder that meters the pellets into the conveying line from a surge hopper. A specially selected positive displacement blower provides the motive air, which is then accelerated through a venturi injector to entrain the pellets. The dilute phase granular material conveying engineering approach minimizes particle-to-particle contact and reduces impact forces, resulting in virtually no pellet breakage or surface damage. The entire system is controlled by a programmable logic controller (PLC) with touchscreen interface, allowing operators to adjust air velocity, feed rate, and pressure in real time.

Key Technical Features and Advantages

One of the standout features of this project is the integration of a dense-phase bypass system that automatically switches to dilute phase when conveying non-friable materials. However, for the primary application of plastic pellet dilute phase conveying, the system operates in a true dilute phase mode with a conveying velocity between 15 and 25 m/s. This velocity range ensures that even light and irregularly shaped pellets remain airborne, preventing settling and blockages. The pipeline is constructed from wear-resistant stainless steel with smooth inner surfaces to reduce friction and static buildup. Additionally, the system includes a cyclonic separator and a reverse-jet filter to capture fine dust and return clean air to the environment. The client reported a 40% reduction in energy consumption compared to their previous mechanical conveyor system, and maintenance costs decreased significantly due to the elimination of moving parts such as chains and belts. The plastic raw material conveying process now runs continuously with uptime exceeding 99.5%.

Implementation and Project Results

The implementation phase took approximately 12 weeks from design to commissioning. Shandong Headpowder Engineering Co., Ltd.’s experienced team handled all aspects, including site survey, layout optimization, equipment fabrication, installation, and startup training. The dilute phase granular material conveying engineering approach required careful alignment of the pipeline to avoid sharp bends and long horizontal sections where pellets could settle. Through advanced computational fluid dynamics (CFD) simulation, the pipeline was routed with a minimum bend radius of 6 times the pipe diameter, and a series of booster air injectors were installed at strategic intervals to maintain velocity. After commissioning, the system achieved a consistent conveying rate of 10.5 tons per hour, slightly exceeding the design target. The client’s quality control team confirmed that pellet breakage was reduced to below 0.1%, far better than the industry standard of 0.5%. Noise levels also dropped to 75 dB(A) at 1 meter, meeting the workshop’s environmental requirements.

Customer Testimonial and Long-term Partnership

The Tianjin plastics enterprise expressed high satisfaction with the project. Their production manager noted that the plastic pellet dilute phase conveying system has greatly improved the stability of their injection molding processes, as consistent material flow eliminates fluctuations in melt temperature and cycle time. The company has since expanded its collaboration with Shandong Headpowder Engineering Co., Ltd. to include additional plastic raw material conveying lines for a new extrusion workshop. This case demonstrates the effectiveness of dilute phase technology in handling sensitive granular materials without compromising throughput or quality. For any enterprise seeking reliable pneumatic conveying solutions, Shandong Headpowder Engineering Co., Ltd. offers complete engineering, manufacturing, and after-sales service from its base in Shandong, China.

Contact Information

For more details about this project or to discuss your own plastic pellet dilute phase conveying requirements, please contact the project manager: Manager Zhang. You can reach him via WeChat at 15662777102. Shandong Headpowder Engineering Co., Ltd. is committed to providing the highest quality plastic raw material conveying and dilute phase granular material conveying engineering solutions tailored to your specific production needs. Feel free to reach out to Manager Zhang for a free consultation and quotation.