Illuminate Your Filtration: Exploring Candle Filters in Pharma
March 15, 2024

Illuminate Your Filtration: Exploring Candle Filters in Pharma

In pharmaceutical manufacturing, ensuring purity and clarity of products is paramount. Among the array of filtration techniques, one stands out for its efficiency and effectiveness - the candle filter. In this article, we delve into what candle filters are, their purpose in pharmaceutics, and their significance in maintaining quality standards, along with exploring innovative solutions for filtration.

What is a Candle Filter in Pharmaceutics?

A candle filter is a type of depth filter used in pharmaceutical manufacturing processes. It consists of a cylindrical housing filled with stacked candle-like filter elements. These elements are typically made of porous materials such as ceramic, metal, or polymeric membranes. Each candle acts as an individual filtration unit, collectively forming a barrier that traps impurities while allowing the desired components to pass through.

Purpose of a Candle Filter:

  1. Particle Removal: One of the primary purposes of candle filters is to remove particles and contaminants from pharmaceutical formulations. These particles can include debris, microorganisms, and other impurities that may compromise the quality and safety of the final product.
  2. Clarification: Candle filters are instrumental in achieving product clarity by effectively separating suspended solids and turbidity from liquids. This clarity is crucial for ensuring visual inspection of the product and maintaining its aesthetic appeal.
  3. Product Quality Assurance: By providing a reliable means of filtration, candle filters play a vital role in upholding quality standards in pharmaceutical manufacturing. They help prevent product defects and ensure consistency in composition and purity.
  4. Process Efficiency: Candle filters offer efficient filtration with minimal product loss, making them a cost-effective solution for large-scale production. Their high dirt-holding capacity and ability to withstand repeated use contribute to process efficiency and productivity.
  5. Regulatory Compliance: Pharmaceutical manufacturing processes must adhere to stringent regulatory guidelines to ensure product safety and efficacy. Candle filters aid in compliance with these regulations by facilitating the removal of impurities and maintaining product integrity.

Innovative Solutions

Schematic specialises in designing and manufacturing advanced candle filter systems tailored to meet the specific needs of pharmaceutical and industrial applications. These systems feature a unique design comprising a group of columnar filter elements sealed within a robust pressure vessel. This configuration enables the production of a cake with dry solids contents of up to 80% and filtrate of extremely high clarity, surpassing industry standards.

Customisable and versatile, these candle filters offer a range of functionalities including thin-cake pressure filtration, cake washing, drying, re-slurry, automatic discharge, and heel filtration. Whether for clarification or recovery applications, these filters excel in handling liquids with low solids content ranging from 5% to less than 1%, and even trace amounts.

Safety is paramount in these designs. Unlike traditional leaf filters where carbon removal poses a manual handling risk, candle filters feature a multi-tube carbon filter design with automatic discharge. This innovative feature ensures that carbon is directly discharged into a container without any manual human contact, mitigating the hazards associated with pyro-hazardous materials.

Moreover, these candle filter systems are engineered to handle a wide range of challenging substances, including solvents, concentrated acids, and other toxic products. With complete containment during filtration, these systems provide a safe and reliable solution for processing hazardous materials.

Explore our product here.

Difference Between Candle Filter and Leaf Filter

While both candle filters and leaf filters are used for filtration purposes, they differ in their design and operation. Candle filters, as described earlier, utilise stacked candle-like filter elements within a cylindrical housing, offering efficient filtration with minimal product loss. In contrast, leaf filters consist of a series of filter leaves arranged in a vertical or horizontal configuration, requiring manual handling for carbon removal after each operation, which poses potential safety risks. The multi-tube carbon filter design of candle filters, with automatic discharge, ensures safer operation and enhanced efficiency compared to traditional leaf filters.


Candle filters, with their efficiency in removing impurities while maintaining product integrity, are pivotal in pharmaceutical filtration processes. The integration of innovative candle filter systems further elevates filtration standards, offering customisable solutions for diverse applications. As technology advances, the synergy between traditional filtration methods and cutting-edge solutions like candle filters promises a future of enhanced quality and safety in pharmaceutical manufacturing. For more information on these innovative solutions, contact us for personalised assistance.

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