The Technology Behind One of the World’s Longest Pipe Conveyors
A 15-kilometer-long pipe conveyor near Hebi, China, was successfully commissioned in 2017. The conveyor carries 1,000 metric tons per hour (T/hr) of coal from the Yubei coal base to two 660-MW coal-fired boilers at the Hebi Heqi Power Plant. The system is the world’s longest single-flight pipe conveyor, surpassing the previous record of 8.2 kilometers (km) by a wide margin.
This article reviews some of the unique technical features of this conveyor system, including its low-rolling-resistance belt, light-weight elevated truss, self-powered maintenance trolley, and mid-booster drive design.
The belt is folded into a tubular shape with overlap by six idler rolls forming a hexagon. The main benefits of pipe conveyors are their ability to accommodate sharp curves and seal the transported material. The pipe belt encloses and separates the material from the environment. The pipe belt also has smaller area moment of inertia compared to a trough belt with the same width, which facilitates the bending of the pipe belt over horizontal and vertical curves. Over the last 15 years, pipe conveyors not only have more installations, longer conveyor lengths, and higher capacities, but also have gained better recognition among end-users in different industries as a feasible material-handling system.
The Yubei Coal Logistic and Storage Base is located in the northern part of the Henan province in China, near Hebi. The coal base is designed to handle 20,000,000 metric tons of coal per year and can store 800,000 metric tons of coal at any given time. It receives coal from nearby mines by rail and truck transport, stores and blends coal of different grades, and sends the coal to local consumers. About 7,000,000 metric tons are transported to two power plants, using a 30-km-long conveyor system.
The first 15-km conveyor—Yubei Section A—starts from the Yubei coal base and ends at the Fenghe Tongli Power Plant, which has two 300-MW and two 600-MW units. Yubei Section A has a design capacity of 1,850 T/hr. Some of the coal is consumed by the Fenghe Tongli Power Plant, and some is transported by a second 15-km conveyor—Yubei Section B—from the Fenghe Tongli Power Plant to the Hebi Heqi Power Plant.
Yubei Section B has a design capacity of 1,000 T/hr. There are two 4,000-metric-ton silos between the Section A and Section B conveyors. Figure 1 shows the Section B pipe conveyor coming to the coal storage yard of the Hebi Heqi Power Plant. Yubei Section B was commissioned in 2017.