Global Processing

Chinese port terminal cleans grain efficiently with high-capacity screener

August 23, 2005

The new port terminal at Dalian, China is one of the most modern in the world, and is the integral component in an ambitious, long-term program to modernize the national grain storage and handling infrastructure of the People’s Republic of China. This high capacity, state-of-the-art facility is the primary port for China’s northeast grain corridor and is owned and managed by the Dalian Beiliang Co. Ltd. Officially called the Beiliang Port, Dalian Bulk Grain Handling Facility of the China Grain Distribution and Marketing Project, it is one of the largest terminals of its type ever built. Its primary purpose is to handle grain imports and exports on the world market, and is the focal point of grain handling and shipment in the North China region. Original plans for the Dalian Port Terminal called for only a main transfer storage facility consisting of 128 silos with a total capacity of 400,000 metric tons to hold grain awaiting shipment. Twenty long-term storage tanks, each with a 30,000 metric ton capacity, were added to the project in 1999 and 2000, giving the Dalian Port Terminal a total grain storage capacity of one million metric tons, or more than 33 million bushels.

The Dalian Port Terminal also includes a 600 million metric ton long-term storage complex. This complex has 20 silos filled with wheat, corn and soybeans and is part of the Chinese national grain storage program. The primary grain import at the Dalian Port Terminal is wheat at a projected volume of approximately three million metric tons (MT) a year. Corn is the main export, with an estimated volume of 8.1 million MT annually. It is stored at the Dalian Port Terminal and is exported to other parts of China or the Far East.

Adding high efficiency screening

Site work on the dock and silo complexes began in 1995 and operations began in 2000. Early in the planning process, Dalian Beiliang turned to ROTEX Inc. in Cincinnati, OH for expertise in specifying a high volume grain screening system to remove dockage from wheat prior to long-term storage. ROTEX Sales Representative Leon Feng, based in Shanghai, made an initial sales presentation describing the grain cleaning capabilities of the Rotex MEGATEX™ Screener to Dalian Beiliang officials in China in 1998. Later that year, a delegation from Dalian Beiliang had an opportunity to see several screeners in action, including a MEGATEX Screener, during a U.S. tour arranged by T.E. Ibberson Co. of Hudson, MN. They were impressed by the capability of the MEGATEX Screener to screen grain up to 1,000 TPH.

As the group narrowed its options, Rotex Vice President of Sales and Marketing Nash McCauley and Feng made a technical presentation on grain cleaning to a group of 20 engineers from Dalian Beilang, describing how the MEGATEX Screener combines high capacity without loss of good grain. The Chinese chose the MEGATEX Model 4280-2 Two Deck Screener, with 280 square feet (26 square meters) of screening area, per deck.

The most important factor in the selection of the MEGATEX Screener was its successful use in most of the major U.S. export grain terminals for 30 years. The ability to change screens easily was also an important factor since the port facility handles three grains — soybeans, corn and wheat. The proven drawer type screen frames of the MEGATEX design provided easy-change capability.

The MEGATEX Screener has been operational since November 2000, and is cleaning wheat at a rate of 500 mtph, with the final product containing less than 0.5 percent dockage. It cleans corn at a rate of 1000 mtph, and removes 70 percent of all foreign material, with the final product containing less than 0.5% dockage.

Design enhances performance

MEGATEX Screeners achieve greater productivity by combining two design innovations: wide screens and long-stroke, gyratory motion. Utilizing screen surfaces that are wider, rather than longer, significantly reduces bed depth, which enables MEGATEX Screeners to handle increased capacity while maintaining screening accuracy. To achieve a wide screening area in a compact design, MEGATEX screeners use a two-bank, multi-level screen deck arrangement to present 16'' to 50'' of width to the feed. This keeps bed depth low and maintains screen accuracy and efficiency at high capacities.

The MEGATEX Screener’s long stroke, low frequency motion creates a force level that serves two important functions. First, it equally spreads the material across the full width of the distribution panel and into the feed doors to proportionally feed each of the screen levels. This ensures full use of all the screening area. Secondly, it produces effective ball mesh cleaning to control screen blinding and provide long-term, uninterrupted operation that ensures product quality. The low frequency, gyratory screening also produces extremely low noise levels, far lower than those produced by vibratory screeners, and well within the comfort zone.

The MG model is available in three sizes – 210, 280 or 350 square feet of screen area, and is designed for higher capacity applications of materials in the 12 mm to 850 microns size. The MG is ideal for high capacity screening demands in export grain terminal operations, inland grain cleaning, fertilizer loading, particle board face/core separations and wood chip classification. The MA models feature an auto-tensioning design that utilizes spring tension clips to provide constant screen tension, which when combined with a drawer type screen frame, provides quick and easy screen changes.