Sludge Spiral Heat Exchangers from Alfa Laval can help keep a digester warm, preheat sludge before dewatering, pasteurize sludge and perform a wide range of other sludge heating applications. The compact, energy-efficient unit is self-cleaning, reducing operating costs. Maintenance costs are reduced due to easy access and its small size means less heating medium is required. It has high heat transfer efficiency and low pumping power consumption, with the ability to handle two highly fouling fluids. Every unit is fully drainable. 866/253-2528; www.alfalaval.us.