title: Characteristics and composition of fouling caused by pig slurry in a tubular heat exchanger--recommended cleaning systems.
abstract: The structure and composition of the fouling deposits caused by pig slurry heated in a tubular heat exchanger were characterized to understand their formation and thus be able to minimize fouling and define effective routine cleaning methods. Two temperatures (55 °C and 80 °C) were investigated. Two types of fouling were identified: organic/mineral and biofilm. The first only formed at temperatures above 50 °C, often during the heating phase, and was the main problem encountered in treatments at 80 °C. Organic/mineral deposits formed a thin compact sub-layer and a thick porous top layer composed of 67-76% minerals, 9-15% proteins, 8-20% carbohydrates and 0-5% fats. Biofilms formed at temperatures between 25 °C and 70 °C in both the cooling and heating sections of the exchanger. This type of fouling predominated at temperatures below 55 °C. The biofilm covered a thin mineral base layer. Strongly acidic or alkaline washing cycle are recommended to clean Type I deposits, while in-line gas-rumbling is recommended for Type II fouling.
authors: Irstea-Rennes, Rennes, France.
authors: C
authors: C
authors: Cunault
authors: Y
authors: Y
authors: Coquinot
authors: C H
authors: CH
authors: Burton
authors: S
authors: S
authors: Picard
authors: A M
authors: AM
authors: Pourcher
mesh_terms: D000822:Animal Husbandry; D000818:Animals; D018441:Biofilms; D057219:Biofouling; D052918:Environmental Restoration and Remediation / Q000295:instrumentation / Q000379:methods*; D006358:Hot Temperature; D007700:Kinetics; D008372:Manure / Q000382:microbiology*; D008855:Microscopy, Electron, Scanning; D010865:Pilot Projects; D013552:Swine
chemical_list: D008372:Manure