What is a Scraped Surface Heat Exchanger?
A scraped surface heat exchanger uses rotating blades to continuously scrape product from the heat transfer surface, preventing fouling and enabling processing of materials that would clog conventional heat exchangers. The scraping action maintains a clean heat transfer surface, ensures uniform product treatment, and handles viscous, sticky, and crystallising products that defeat shell and tube and plate heat exchangers.
The scraped surface design provides several unique capabilities: it processes highly viscous products by mechanical transport rather than relying on fluid flow; it prevents burn-on and fouling by continuously renewing the product layer at the heat transfer surface; and it enables crystallisation and freezing applications where solid formation would otherwise block heat transfer. These capabilities make scraped surface heat exchangers essential for food processing and specialty chemical applications.
How Does a Scraped Surface Heat Exchanger Work?
Rotating Scraper Mechanism
A central shaft with attached scraper blades rotates within a cylindrical heat transfer tube. The blades maintain close clearance to the tube wall, continuously removing product from the heat transfer surface. This mechanical action ensures all product contacts the temperature-controlled surface for uniform heating or cooling.
Heat Transfer Surface
The heat transfer tube is jacketed for circulating heating or cooling media—steam, hot water, glycol, ammonia, or other thermal fluids. Heat transfers through the tube wall to the product film created by the scraper action. The thin, constantly renewed product film provides efficient heat transfer despite high product viscosity.
Product Flow
Product flows axially through the annular space between the rotating shaft and the heat transfer tube. The scraper blades transport product forward while ensuring contact with the temperature-controlled surface. Multiple units can be arranged in series for staged heating, cooling, or crystallisation.
Types of Scraped Surface Heat Exchangers
Votator-Type Scraped Surface Heat Exchangers
Votator scraped surface heat exchangers represent the original and most widely recognised design. The horizontal cylinder with rotating mutator shaft and spring-loaded blades handles diverse food processing applications. Votator units are industry standards for margarine crystallisation, ice cream freezing, and viscous product heating/cooling.
Contherm Scraped Surface Heat Exchangers
Alfa Laval Contherm scraped surface heat exchangers feature vertical or horizontal configurations with various scraper designs for different product characteristics. Contherm units serve food, dairy, and specialty applications requiring gentle or intensive scraping action.
Terlotherm Scraped Surface Heat Exchangers
Terlet Terlotherm scraped surface heat exchangers provide efficient thermal processing for food and chemical applications. The robust design handles demanding products and operating conditions.
Scraped Surface Heat Exchanger Applications
Scraped Surface Heat Exchangers for Food Processing
Food scraped surface heat exchangers process viscous products that would foul conventional exchangers. Applications include margarine and shortening crystallisation, ice cream and frozen dessert freezing, sauce and filling heating/cooling, peanut butter tempering, and chocolate processing. The scraping action prevents burn-on, ensures uniform treatment, and handles products that change viscosity dramatically during processing.
Scraped Surface Heat Exchangers for Dairy Processing
Dairy scraped surface heat exchangers freeze ice cream mix, cool cultured products, and process cream-based products. The gentle scraping action preserves product quality while achieving required temperature changes. Hygienic design with CIP capability meets dairy industry standards.
Scraped Surface Heat Exchangers for Chemical Processing
Chemical scraped surface heat exchangers handle crystallisation, cooling of viscous polymers, and processing of fouling chemical streams. The mechanical scraping prevents surface build-up that would reduce heat transfer and cause quality problems. Specialty materials handle corrosive products.
Scraped Surface Heat Exchangers for Pharmaceutical Production
Pharmaceutical scraped surface heat exchangers process ointments, creams, and viscous formulations requiring precise temperature control. Sanitary construction meets GMP requirements. The gentle processing preserves product quality while achieving thermal objectives. Products may proceed to mixers for blending or filling equipment for packaging.
Scraped Surface Heat Exchanger Manufacturers at Foeth
Votator – The original scraped surface heat exchanger design, industry standard for food processing
Alfa Laval – Contherm scraped surface heat exchangers for food and dairy applications
Waukesha Cherry-Burrell – Scraped surface heat exchangers for food and beverage
APV – Thermal processing equipment including scraped surface designs
Terlet – Terlotherm scraped surface heat exchangers for food and chemical industries
HRS Heat Exchangers – Scraped surface and corrugated tube heat exchangers
Why Buy Used Scraped Surface Heat Exchangers from Foeth?
Specialised Capability
Scraped surface heat exchangers solve thermal processing challenges impossible with conventional exchangers. For viscous, fouling, or crystallising products, scraped surface technology is often the only viable option.
Proven Performance
Used scraped surface heat exchangers from Votator, Alfa Laval, and other premium manufacturers deliver proven thermal processing performance. The robust construction ensures long service life even in demanding food processing environments.
Cost-Effective Solution
Pre-owned scraped surface heat exchangers provide significant savings compared to new equipment while delivering equivalent processing capability. For capacity expansion or equipment replacement, used units offer compelling value.
Immediate Availability
Our scraped surface heat exchanger stock enables rapid deployment without lengthy manufacturing lead times. Tested units are ready for installation and production.
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Request a Scraped Surface Heat Exchanger Quote
Find the right scraped surface heat exchanger for your viscous product processing needs. Browse our scraped surface heat exchanger inventory and request a quote online, or contact our team for expert advice.
