STEAM FILTRATION :

Steam is commonly used for cleaning, sterilizing, heating , as a power source and as a feedstock in chemical reactions. Un all these cases the steam supply should be fine filtered to remove the significant amount of scale and debris produced by the boiler and distribution system pipe work.

When the steam is used for heating food or beverage products by direct injection – for example in the continuous sterilization of dairy products by uperisation – then the steam is known as culinary steam and will be subject to a range of purity requirements.

Direct steam injection using culinary steam in food processing is an effective method to warm food and reduces the speed of production because the product absorbs the heat more rapidly. Culinary steam “should be free of entrained contaminants (e.g., excess condensate, rust, pipe scale, and boiler feed water additives) and relatively free of water in liquid form.”

Accepted practices require that the filters used should be nontoxic and should not release media, toxic volatiles, or other contaminants into the steam. The bonding materials should be nontoxic, non-volatile, and insoluble under the intended conditions of use. Accepted practices require the filter to be capable of removing 95% of particles that are 2 µm or larger with an associated condensate trap. Presents an overview of a system for direct steam injection.2

Cahoon Farms (Walcott, N.Y.), a manufacturer of private label applesauce, recently described an example of the use of a coalescing filter for the purification of steam for direct steam injection.3 This filter system provides steam with an efficiency of 98%, removing all particles of rust, pipe scale, and other contaminants.

These filters are in full compliance with the 3A accepted practices (609-04) for producing culinary quality steam. In addition, they meet the regulations for Indirect Food Additives used as Basic Components for Repeated Use Food Contact Surfaces as specified in 21 CFR 177, Current Good Manufacturing Practices 21 CFR Part 110, and have been accepted by the U.S. Department of Agriculture for use in federally inspec

CulinarySteam

Culinary steam is defined by 3A Standard 609-01 as “Steam that is free of entrained contaminants, relatively free of water in liquid form and is suitable for use in direct contact with milk or milk products or product contact surfaces.” In practice this means that the steam filter should be capable of removing 95% of particles 2 microns in size and be manufactured from 300 series stainless steel or higher. Suitable grades are available in sintered metal fibre, mesh and powder for this application. Steam filtration increases system efficiency and protects sterile equipment, removes pipe-scale to prevent fouling of valves or injectors and inhibits contamination of product.

BENEFITS OF STEAM FILTRATION :

• Prevent fouling of critical orifices and components.
• Prevent contamination of sterile equipments.
• Prevent contamination of food and beverage products.
• Increase process efficiencies.
• Prevent premature blockage of downstream filters.  

Results into :

• Increased cleanliness
• Better products quality – no particulate matters.
• Less down time in plants.

FILTER MEDIA :

The steam filter is generally made up of S.S. 316 or S.S.316L material which is converted in to steam filter by sintering process to control pore structure. The sintered stainless steel media

• Physically strong hence no damage during use
• Low resistance to flow hence less pressure drop
• Good corrosion resistance hence longer service life
• High temperature withstanding capacity
• Repeatedly cleanable hence economical option.
• No extractable or no media migrations.