I. Background: From “ Sugar Production ” To “ Refined sugar ” , The filtering process determines the profit.

In the modern sugar industry, filtration and pressing have long ceased to be mere steps for simple solid-liquid separation—they directly influence sugar juice yield, energy consumption levels, and the final product quality.
In the past, sugar companies primarily used sugarcane or sugar beets as raw materials, but today, with the advancement of comprehensive resource utilization and the bio-based industry, Corn Cob Sugar Production It is gradually entering the mainstream spotlight.

Corn cobs contain hemicellulose-derived sugars such as xylose and arabinose, which can be converted into chemical building blocks like xylitol, furfural, and ethanol through acid hydrolysis or enzymatic breakdown.
However, the production of corn-cob sugar is characterized by high slurry viscosity, coarse and long fibers, and a high moisture content—especially during Secondary Pressing and Dewatering Stage In this process, insufficient separation efficiency will lead to significant sugar loss and filter cloth clogging issues.

Therefore, How to enhance sugar liquid recovery, reduce moisture content, and extend filter cloth lifespan through the synergistic operation of industrial filter cloths and belt press filtration machines. , becoming a key issue in the sugar industry.

II. Challenges and Filtration Requirements of Secondary Pressing Corn Cobs

After the corn cobs are hydrolyzed, the residue still retains approximately 8%–12% The soluble sugars. This portion of sugary liquid is trapped within the fiber pores, making it difficult to effectively release through conventional pressure filtration.
In the secondary pressing process, the material forms a semi-solid, fibrous slurry that is neither suitable for high-speed centrifugation nor easily processed using a plate-and-frame filter press.

The main challenges include:

1. High viscosity, prone to paste the fabric : Corn cob residues have high sugar content and significant surface tension, making them extremely prone to forming on the filter cloth surface. “ Sugar Film ” , blocking the filter pores.
2. The filtrate has low clarity. : Fine fibers and colloidal particles are difficult to completely intercept, causing the filtrate to remain cloudy and affecting subsequent sugar solution purification.
3. Dehydration is difficult, and the filter cake has a high moisture content. : Traditional pressing struggles to form a uniform filter cake, resulting in low pressing efficiency.
4. Filter cloth has a short lifespan. : High-temperature, highly acidic sugar liquid environments accelerate the aging of filter cloths, requiring frequent replacements and increasing costs.

Precisely for this reason, sugar factories have been actively introducing Belt Press Filter Machine Belt Filter Press ） and is equipped with high-performance industrial filter cloths to enable continuous, automated, and energy-efficient production.

III. Belt Press Filter: An Efficient Solution for Continuous Separation

A belt press filter is a continuously operating solid-liquid separation device, with its core consisting of two filter cloths—one above and one below—that achieve multi-stage squeezing via a roller system.
Its typical workflow consists of three stages:

1. Gravity Pre-Dewatering Zone :The slurry is evenly spread onto the filter cloth, allowing free water to drain off under gravity, thereby reducing the load on subsequent pressing.
2. Wedge-shaped Pre-compression Zone : The upper and lower filter cloths gradually converge, and gentle pressure is applied as the material passes between the rollers, loosening its structure and forcing liquid to drain out.
3. High-pressure Squeezing Zone :The filter cake is repeatedly compressed between multiple sets of pressure rollers, removing bound water and achieving thorough dewatering.

This structure gives the belt press a significant advantage in the secondary pressing of corn cobs:

• Continuous operation with high throughput;
• Low energy consumption, smooth operation;
• The filtrate has high clarity;
• The equipment features a compact design and is easy to maintain.

Especially in continuous production scenarios at sugar mills, the belt press's online cleaning system ensures long-term, unobstructed operation of the filter cloth, preventing downtime caused by sugar liquid solidification.

IV. Key Technologies for Industrial Filter Cloth: From “ Dehydration ” To “ Anti-stick ”

The filter cloth is for the belt press filter machine. “ Soul Components ” It both undertakes the separation task and determines the overall system's flux and lifespan.
Given the characteristics of sugar production from corn cobs, the filter cloth design must be carefully considered. “ Dehydration speed, anti-clogging capability, and dimensional stability ” Achieving a balance between them.

1.  High-throughput and low residual sugar rate

The filter cloth pore size must be controlled within a reasonable range, ensuring that the sugar liquid can pass through quickly while solid particles are effectively retained.
A filter cloth that is too dense will reduce the flow rate, while one that is too sparse will cause sugar liquid entrainment. Therefore, precise air permeability design is essential—approximately 100–200 L/m²·s ) Particularly crucial.

2.  Surface Anti-Clogging and Self-Cleaning

Corn cob pulp is rich in glycosaminoglycans, making it highly prone to forming filter cake adhesion. For this reason, the surface of filter cloths often employs Smooth weaving structure or non-stick coating , when combined with a high-pressure water cleaning system, can significantly delay the caking of the fabric.

3.  High strength and dimensional stability

In belt press machines, the filter cloth must withstand long-term tension and repeated bending; therefore, its warp-and-weft structure needs to exhibit excellent tensile and flexural resistance to ensure smooth operation without deviation.

4.  Chemical Resistance and Food Safety

The filtration process involves contacting weakly acidic sugar liquid with hot water. The filter cloth must exhibit acid- and alkali-resistant properties as well as hydrolysis resistance, and it should meet food-grade production standards to ensure the sugar liquid remains pure and free from contamination.

V. Process Optimization: A Key Step to Enhancing Sugar Factory Profits

Besides the filter cloth and equipment performance, system operating parameters also determine the filtration efficiency.
The following four aspects are the core of optimizing the corn cob secondary pressing system:

1. Feed Conditioning and Flocculation Control
   By adding an appropriate amount of inorganic or organic flocculants, fine particles can be promoted to coalesce, improving the filter layer structure and resulting in clearer filtrate.
2. Speed and Tension Adjustment
   Control the filter cloth line speed (usually 1.5–3 m/min ) Along with the squeezing pressure gradient, it can balance the dewatering rate and filter cloth wear.
3. Cleaning and Maintenance System
   The online spray, backwash, and recirculation flushing system prevents filter clogging and extends the lifespan of the filter cloth.
4. Segmented Squeezing Design
   Based on the moisture characteristics of corn cob residue, a multi-stage roller press structure can be employed to achieve “ Step-by-step dehydration ” , reducing the moisture content of the filter cake to 40% The following.

After optimization, typical sugar refinery data show:

• Sugar liquid recovery rate improved by approximately 3%；
• The moisture content of the filter cake decreases. 10% to 15% ；
• Filter cloth lifespan extended 30%；
• Overall energy consumption decreases 12%。

6. Xadias' Filtration Technology Practices

In the sugar and biomass industries, Xiamen Xiadis Filtration Materials Technology Co., Ltd. ( CITIUS Filter Media ) Long-term provision of matching filter cloth solutions for belt press filters.
For sugar-cane bagasse, sugarcane pulp, beet pulp, and other by-products from the sugar-extraction process, Xadias has developed Highly Hydrolysis-Resistant Filter Cloth Mesh Belt It has the following features:

• High-Strength Structural Design : The tension of the latitude and longitude lines remains balanced, ensuring no deformation during long-term operation;
• Anti-clogging and Quick-Wash Process : The filter cloth boasts high surface smoothness, enabling more thorough online cleaning;
• Customized sizes with edge reinforcement : Meeting the pressing needs of different models;
• High water permeability and excellent filtrate clarity : Effectively enhances sugar liquid recovery rate;
• Optional food-grade non-stick coating : Prevent the sugar liquid from carbonizing and sticking.

In the operation of several sugar factories, Xadias filter cloths have helped customers achieve “ High recovery rate, low energy consumption, long lifespan ” Its stable operation helps the industry save significant operational costs.

7. Trend Outlook: Intelligentization and Green Manufacturing Moving in Parallel

The sugar industry is transitioning from traditional, extensive-type production to “ Intelligent, low-carbon, clean ” Directional development. The future belt press systems will no longer be merely separation equipment—they will become intelligent process nodes.
The main trends include:

1. Online Monitoring and Intelligent Control
   Key parameters such as filter cloth tension, filtrate turbidity, and moisture content can be monitored in real time, while the system automatically adjusts operating speed and pressure to enable unattended operation.
2. New nanomicro-fabric filtration material
   By utilizing nano-modified fibers or functional coatings, more precise particle retention and self-cleaning effects can be achieved.
3. Energy Recovery and Recycling
   By integrating a heat recovery system, the waste heat from pressing can be utilized in sugar liquid concentration or drying processes, thereby enhancing overall energy efficiency.
4. Sustainable Material Applications
   Promoting renewable, polymer-based eco-friendly fiber filter fabrics aligns with the green manufacturing and environmental sustainability trends in the food industry.

VIII. Conclusion: Efficient Filtration Powers Sustainable Development in the Sugar Industry

Corn cob sugar production through secondary pressing is not only a technical step to enhance sugar yield, but also a crucial move toward achieving resource recycling.
The combination of belt press filters with high-performance industrial filter cloths has breathed new life into this traditional process.

In the future, as equipment becomes smarter and filter cloth technology advances, the filtration process will become a key component of the sugar-making industry. “ Efficiency Amplifier ”。
Xadiaas CITIUS ) Will continue to leverage 30 years of industry experience to provide professional filtration solutions for the global sugar, chemical, and biomass utilization sectors, driving industrial separation technologies toward greater efficiency, sustainability, and intelligence.