The gravity separator—also known as a gravity sorter—is a precision processing machine distinct from the preliminary coarse-cleaning gravity destoner. It is utilized after air-screen cleaning and destoning to perform fine sorting based on differences in particle density (specific gravity). It is specifically designed to remove particles that share the same size as good product but differ in weight—such as shriveled, insect-damaged, moldy, or immature light grains, as well as half-broken seeds, empty husks, and diseased or damaged kernels—while also providing supplementary destoning capabilities.
It is widely integrated into processing lines for sesame seeds, coffee beans, various coarse grains, and seeds.
The gravity separator core components
Uniform Feeding Hopper
Equipped with a flow-regulating gate to ensure even and stable material distribution and controllable layer thickness. It connects directly to elevators for continuous, automatic feeding, preventing material clustering or uneven layering.
304 Stainless Steel Honeycomb Air-Distribution Gravity Deck (Core Component)
Features a honeycomb structure for uniform airflow, eliminating localized high-velocity currents and ensuring consistent suspension height across the material layer. The deck inclination, vibration amplitude, and air pressure are all adjustable to suit various particles such as coffee beans, sesame, legumes, and seeds. The wear-resistant woven mesh resists clogging and corrosion.
Multi-Channel Independent Fan System
Utilizes segmented, independent air chambers allowing for precise fine-tuning of airflow in each zone for accurate stratification. Positive-pressure fluidization ensures clear material suspension and separation, while the enclosed air duct design prevents dust leakage.
Dual Vibration Motor Drive Mechanism
Symmetrical vibration motors provide reciprocating directional oscillation, supported by shock-absorbing rubber mounts. This ensures low machine vibration and noise, maintaining stability without shifting during prolonged operation.
Multi-Channel Discharge Outlets
Four-way separation: plump/heavy finished product, semi-plump semi-finished product, light impurities (shriveled/moldy grains), and heavy impurities (stones). Semi-finished products can be recirculated for a second pass to maximize raw material utilization.
Maintenance/Cleaning Access & Mobile Frame
Side-opening, quick-release access panel allows for rapid removal of residual material. The unit is equipped with both swivel casters and leveling support feet, facilitating easy relocation within the workshop and preventing cross-contamination when switching between product varieties.
Material is evenly spread across an inclined vibrating gravity table; a bottom-mounted fan continuously blows air upwards, creating a fluidized suspension layer of particles.
Automatic Stratification: High-quality, dense, and plump coffee beans or sesame seeds sink to rest against the screen mesh; moldy, insect-damaged, shriveled, or broken lightweight particles float in the upper layer; the heaviest items—stones and soil clods—settle at the very bottom.
Vibrational Separation: The table undergoes directional reciprocating vibration; dense, plump particles from the bottom layer move up the slope and are discharged through the finished product outlet, while lightweight impurities and shriveled grains in the upper layer slide down the slope to be collected at the light-impurity outlet; stones at the bottom are separately discharged through a side stone-removal outlet.
Recirculation for Secondary Sorting: Semi-finished products (partially filled grains) are recirculated to the feed end for re-sorting, minimizing product loss and raising the final purity level to over 99.5%.
1. Coffee Bean Processing Line
Removes shriveled, insect-damaged, moldy, and broken raw beans after dehulling; standardizes bean plumpness; reduces the workload on color sorters; and upgrades the quality of export-grade green coffee beans.
2. Sesame Processing Line (White and Black Sesame)
Removes shriveled seeds, empty hulls, and sprouted or spoiled sesame; performs pre-processing (refining) prior to oil extraction and color sorting to increase oil yield and enhance the visual appeal of the final product.
3. Coarse Grain and Legume Processing
Precision sorting of chickpeas, soybeans, mung beans, peanuts, and sunflower seeds; removes diseased and insect-damaged kernels; suitable for the export of premium coarse grains.
4. Seed Processing
Precision sorting of wheat, corn, vegetable, and forage seeds; retains only plump seeds with high germination rates to meet standards for breeding and precision sowing.
Nov. 07, 2026
2026 gravity separator utilizes differences in material specific gravity to perform sorting. It is specifically designed to remove impurities and inferior-quality grains that are similar in size to the target seeds—particles that are otherwise difficult to separate using conventional air-screen or vibrating-screen cleaners. It serves as a core piece of precision-sorting equipment in processing lines for grains, sesame seeds, and legumes.
Nov. 05, 2026
Sesame seeds are extremely small (approximately 1.5–2 mm in diameter) and flat-oval in shape, with a smooth surface, high oil content, and relatively low specific gravity. These physical characteristics present unique challenges for cleaning: while light impurities—such as stalks, husks, dust, and shriveled or empty seeds—can be removed via air classification (aspiration), and oversized or undersized debris can be intercepted through screening, certain contaminants pose a greater difficulty. Specifically, stones, sand, clods of soil, and metal fragments—which are similar in size to sesame seeds but have a significantly higher specific gravity—cannot be effectively separated by either air classification (as they are too heavy to be moved by airflow) or screening (as they pass through or are retained alongside the seeds).
Nov. 05, 2026
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Nov. 04, 2026
Pakistan is a significant global producer and exporter of sesame seeds, ranking as one of the few oilseed crops for which the country maintains a net export position. According to data from Pakistan’s Ministry of National Food Security and Research, the area under sesame cultivation expanded substantially from approximately 259,900 hectares in the 2022/23 crop year to about 399,800 hectares in 2023/24—an increase of 53%. Production reached approximately 301,200 tonnes, a sharp year-on-year rise of 97.7%. For the 2024/25 crop year, production is projected to climb further to approximately 440,000 tonnes (a 44.7% year-on-year increase), with the harvested area—as recorded by FAOSTAT—exceeding 700,000 hectares. The primary production regions are concentrated in Punjab province (cultivated during the *Kharif* monsoon season, covering approximately 1.76 million acres in 2024) and parts of Sindh province. In recent years, technical cooperation between Pakistan and China, alongside the adoption of contract farming, has led to significant improvements in both crop yields and the level of commercialization.
Nov. 02, 2026
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Nov. 02, 2026
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