In the heart of Xinjiang, Urumqi stands as a major industrial hub for chemical processing, particularly for enterprises dealing with highly reactive materials. One such facility, a chemical plant specializing in sodium sulfide production, faced a critical challenge: how to safely and efficiently transport sodium sulfide powder from storage to downstream processing units without exposing the material to oxygen. Sodium sulfide, a yellowish flake or powder, is notorious for its strong reducing properties. When exposed to air, it rapidly oxidizes, generating heat and potentially leading to combustion or release of toxic hydrogen sulfide gas. Traditional pneumatic conveying systems using ambient air were simply not an option. The plant needed a reliable, closed-loop solution that could maintain an inert atmosphere throughout the entire material handling process. This is where Shandong Headpowder Engineering Co., Ltd. stepped in, bringing its proven expertise in nitrogen protection conveying engineering to design a customized system tailored to the specific properties of sodium sulfide powder.
Easily oxidized chemical materials, such as sodium sulfide powder, require extraordinary precautions during transport and processing. The primary risk lies in the exothermic oxidation reaction that occurs upon contact with oxygen. This reaction not only degrades the product quality—causing discoloration, caking, or complete loss of active content—but also poses serious safety hazards including dust explosions or toxic gas releases. The Urumqi facility had previously attempted conventional dilute-phase conveying with compressed air, but the results were disastrous: the powder oxidized rapidly inside the pipeline, leading to frequent blockages, equipment corrosion, and unplanned shutdowns. The plant's management realized that a fundamental redesign was necessary. They needed a system that could replace the conveying gas with an inert medium, maintain a positive pressure of nitrogen throughout the entire closed loop, and ensure that no oxygen ingress occurred at any point—from the feeding hopper to the storage silo. This requirement perfectly aligned with the core capabilities of Shandong Headpowder Engineering Co., Ltd., a company renowned for its bespoke solutions in the field of nitrogen protection conveying engineering.
After a thorough site audit and material analysis, the engineering team at Shandong Headpowder Engineering Co., Ltd. proposed a nitrogen circulation pneumatic conveying system designed specifically for sodium sulfide powder. The system operates on a closed-loop principle: nitrogen gas is continuously recirculated through the pipeline, picking up the powder from the feed point and transporting it to the destination, while any entrained particles are separated by a high-efficiency cyclone and bag filter. The cleaned nitrogen is then recompressed and returned to the circuit, with only a minimal amount of fresh nitrogen added to compensate for leakage. This design eliminates the need for venting to the atmosphere, thereby preventing any oxygen intrusion. Key components include a nitrogen generator with a purity monitor, a pressure-maintaining rotary valve, a specially designed venturi pick-up device to minimize particle attrition, and a PLC-based control system that continuously monitors oxygen concentration, pressure, temperature, and flow rate. The system is capable of conveying sodium sulfide powder at a rate of 5 tons per hour over a distance of 150 meters, with a conveying line pressure drop of less than 0.3 bar. The entire conveying process is carried out under a nitrogen atmosphere with an oxygen content maintained below 2% by volume, effectively suppressing any oxidation reaction.
Several engineering innovations distinguish this project as a benchmark for nitrogen protection conveying engineering. First, the system employs a dual-inerting strategy: nitrogen is introduced not only as the conveying gas but also as a blanket gas in the feed hopper, filter receiver, and storage silo. This triple-layer protection ensures that even during transient events such as valve cycling or filter cleaning, no oxygen can enter. Second, the rotary valve is equipped with a nitrogen purge port that continuously flushes the rotor pockets, preventing any powder accumulation that could smolder. Third, the pipeline is constructed from electropolished 316L stainless steel with a smooth interior surface to reduce friction and minimize the risk of static electricity buildup, which is critical for a material that can generate flammable dust clouds. Fourth, the system includes an automatic emergency nitrogen purge sequence that activates if the oxygen sensor detects a level exceeding 3%, quickly flooding the entire circuit with nitrogen to inert the atmosphere. The project also incorporated a remote monitoring interface that allows the plant's operators to view real-time data from a control room located 500 meters away, ensuring that any anomalies are detected immediately.
The installation was completed in eight weeks, followed by a rigorous commissioning phase that included a 72-hour continuous run under full load. During this test, the system demonstrated exceptional reliability: the sodium sulfide powder showed no signs of oxidation, with the product's color, particle size distribution, and active content remaining unchanged compared to the original material. The nitrogen consumption was measured at an average of 8 cubic meters per ton of conveyed powder, which is 30% lower than the client's original budget. The plant reported a 95% reduction in maintenance downtime related to the conveying system, and the elimination of hazardous gas emissions. The success of this project has prompted the client to order a second identical system for a parallel production line. The project also earned recognition from the local environmental protection bureau for its contribution to reducing industrial risks.
Shandong Headpowder Engineering Co., Ltd., headquartered in Shandong, China, has been a pioneer in the field of pneumatic conveying and powder processing for over 20 years. The company's core competency lies in handling difficult-to-convey materials—those that are abrasive, friable, hygroscopic, or, as in this case, easily oxidized. The engineering team comprises specialists in chemical engineering, mechanical design, and automation control, who work closely with clients to develop customized solutions. For any project involving sodium sulfide powder conveying, potassium sulfide, sodium hydrosulfide, or other reducing agents, headpowder offers a complete range of services: feasibility study, process simulation, equipment design, fabrication, installation, commissioning, and after-sales support. The company's nitrogen protection conveying engineering technology has been validated in dozens of installations across China, including in the chemical, metallurgical, and pharmaceutical industries.
If you are interested in learning more about how Shandong Headpowder Engineering Co., Ltd. can help you solve your challenging material conveying problems, please feel free to reach out to our project manager, Mr. Zhang. He can provide detailed case studies, technical drawings, and a preliminary proposal tailored to your specific requirements. Mr. Zhang is available via WeChat at 15662777102. We welcome inquiries from all over the world and look forward to discussing how our nitrogen protection conveying engineering can bring safety, efficiency, and reliability to your production line.
The Xinjiang Urumqi project stands as a testament to the effectiveness of well-designed nitrogen circulation pneumatic conveying systems in handling easily oxidized chemical materials. By combining advanced engineering principles with rigorous attention to safety, Shandong Headpowder Engineering Co., Ltd. delivered a solution that not only met but exceeded the client's expectations. The project demonstrates that with the right partner, even the most challenging materials can be transported reliably and safely. For any enterprise dealing with sodium sulfide powder, sodium hydrosulfide, or similar reactive substances, investing in a nitrogen protection conveying engineering system is not just a technical upgrade—it is a fundamental step toward operational excellence and risk mitigation. Contact Mr. Zhang at WeChat 15662777102 to start your journey toward a safer and more efficient powder handling process.
Shandong Headpowder Engineering Co., Ltd.
156-6277-7102（Zhang manager） 
0531-83386006 
Jinan City, Shandong, China Province 
telephone
WeChatconsult
top