Efficient powder recovery after spray drying can be very challenging, especially for expensive products or small particle sizes. Spray dryers typically have a high-efficiency cyclone and baghouse after the drying chamber to prevent product from escaping into the exhaust gas.

Cyclones offer excellent hygienic properties. Unlike baghouses, cyclones avoid product contamination through filter fibers, making them a must-have spray drying layouts in pharmaceuticals. Cyclones are easy, fast and effective in clean-in-place, allowing for the rapid and effective separation of different powder batches without cross-contamination of products. Therefore, a baghouse placed downstream of the cyclone only serves to protect the HEPA filter, and the collected powder may be discarded. Product losses caused by using an inefficient cyclone result in increased costs. Even if the product is inexpensive, it is considered to be environmentally and socially irresponsible, so improving product collection efficiency is also a waste management issue that needs to be addressed. It is important to use cyclones that are easy and quick to clean, not only to maximize powder yield but also to enable rapid product changeover.

Featuring a range of GMP-compliant, high-efficiency cyclones, ACS solutions dramatically reduce losses, even with the finest products. Every model is individually optimized to meet the requirements of the installation. Smaller units use only a tri-clamp and can be disassembled for quick and hassle-free cleaning.

Tablet pressing and encapsulation processes may pose a risk to workers due to dust generation and potential cross-contamination of products between subsequent batches. Therefore, these processes are connected to a local exhaust ventilation system (LEV) equipped with cartridge filters, followed by HEPA filters. ACS cyclones offer best practice waste powder management by providing highly efficient recovery of fine powders, which can be reintroduced into the process, and improving product yield.

ACS offers a wide range of GMP-compliant cyclones for tableting and encapsulation. Cyclones can be applied both for waste powder collection and powder recovery, and are much more efficient than other common cyclones. The cyclone unit includes a catch pot with sight glass and a base on wheels, and can be disassembled using only a tri-clamp for quick and hassle-free cleaning.

There is a wide variety of needs to separate powders from a gas in many industries, from dairy and chocolate to beverages, starch and yeast. Processes requiring product separation include drying (e.g. spray dryers or flash dryers), grinding and mixing. Efficient recovery of food powders can be challenging, especially when the particles are fine. This challenge is particularly seen in spray drying, a process used to dry high-value powder products such as demineralized whey and whey protein concentrate. Spray drying processes typically include a process cyclone and a final dedusting system (such as a baghouse, wet scrubber, or WESP).

In spray drying, process cyclones separate and collect dry powders from gas that has passed through the drying chamber. The portion of the fines that flows into the final removal system is considered a loss because it is waste (WESP and wet scrubber) or not considered a first-grade product (baghouse). The reason why it is not considered as first-grade products is due to the risk of contamination from filter fibers as well as product cross-contamination. The preferred method for highly efficient recovery of expensive powder products is to use cyclones, which capture powders directly and hygienically, not only for initial product recovery but also for final dust removal. Unlike baghouses and wet scrubbers, cyclones can avoid filter contamination and product cross-contamination. For fine powders with a volume median diameter (MVD) below 5 μm, losses due to low cyclone collection efficiency can be 25% or more. Even if the product is inexpensive, it is considered environmentally and socially irresponsible, so improving product collection efficiency is also a waste management issue. The advantages, disadvantages, investment and operational costs of final dedusting options are as follows: