FOULING DURING THE USE OF ‘FRESH’ WATER AS COOLANT- THE DEVELOPMENT OF A ‘USER GUIDE’

IHS ESDU recently published its latest ‘User Guide’ to fouling in heat exchange systems, for systems with fresh water as the coolant. ESDU 07006 [1] is the third in a group, following the development of the Crude Oil Fouling User Guide [2] issued in 2000 and the Seawater Fouling User Guide [3] issued in 2004. ESDU 07006 was developed by IHS ESDU over a period of five years under the guidance of the Oil Industry Fouling Working Party, a collaborative team of oil refiners, heat transfer equipment and services suppliers and Universities. It provides designers and operators of cooling water facilities with a practical source of guidance on the occurrence, the mechanisms and the mitigation of fresh water fouling in these systems. IHS ESDU’s Oil Industry Fouling Working Party was formed in recognition of the huge economic and environmental importance of heat exchanger fouling and the potential benefits that can accrue from better understanding of mitigation strategies. Work is now underway on reboiler and FCCU fouling. The development of the User Guide ESDU 07006 is discussed in this paper and its technical content is summarized

Study of The Influence of Bulk Properties and Surface Tension on the Deposition Process of Calcium Phosphate on Modified Stainless Steel

In order to reduce the fouling caused by milk during heat treatment, it is important to know more about the deposition process of calcium phosphate, one of the main components of milk fouling, on stainless steel surfaces. The fouling behaviour of calcium phosphate is controlled by several factors related to both the fouling solution properties and the surface characteristics. The present work is focused on the influence of two of these factors: 1) the size and size distribution of the calcium phosphate aggregates formed in solution upon heating and 2) the surface tension values of the deposition surface. It was possible to conclude that maximum deposit build up occurs at the temperature corresponding to the formation, in the bulk, of amorphous sphere-like calcium phosphate particles of about 0.1mm diameter and considering the surface effect, the maximum deposition is obtained on those surfaces having higher surface tension values

FLOW CELL STUDIES ON FOULING CAUSED BY PROTEIN -CALCIUM PHOSPHATE DEPOSITION IN TURBULENT FLOW

A comparative study of the calcium phosphate fouling process, with and without proteins, was carried out using both standard 316 2R stainless steel and 2R surfaces modified by TiN magnetron sputtering. Fouling behavior was assessed in a heat transfer flow cell operating in the turbulent flow regime. The fouling curves resulting from calcium phosphate deposition in the absence of proteins were substantially different from the ones obtained when protein was present. In this last case, two different fouling periods could be observed. The surface energy of the modified materials was found to affect the deposition parameters (rate of deposition and final amount of deposit) leading to higher amounts of deposit on higher energy surfaces in the absence of protein, while leading to less deposit in its presence. The standard 316 2R substrate proved to be less prone to fouling from protein-calcium phosphate solutions than the TiN modified surfaces. However, the same conclusion could not be drawn for calcium phosphate solutions

New records from the southern North Sea and first records from the Baltic Sea of Kornmannia leptoderma

Combined genetic, morphological and ontogenetic observations show that the circumarctic boreal green algal macrophyte Kornmannia leptoderma has expanded its distribution range into the Baltic Sea, on a German coastal section of 220 km length. The species is also again (or still) established at its former extreme southern distribution limit in the North Sea, the German island of Helgoland, where it has not been detected during the last four decades. Macroscopic visible sporophytes of K. leptoderma are nowadays present in the Baltic Sea and at Helgoland from February to September, while they were in the past only detected from February to May at Helgoland. This capacity for formation of sporophytes in summer correlates with the circumstance that K. leptoderma from the Baltic Sea can complete its life cycle at 15°C while several studies conducted decades ago with material from Helgoland and from Pacific coasts consistently reported an inhibition of the algal gametogenesis at temperatures that exceed 12°C. Possibly K. leptoderma has undergone adaptations that facilitate its spread into warmer environments, unless the Kornmannia present in the Baltic Sea and on Helgoland today represents a newly introduced cryptic species

Vegetation of the supralittoral and upper sublittoral zones of the Western German Baltic Sea coast: a phytosociological study

Supralittoral and shallow water seaweed communities are particularly exposed to impacts such as climate change and disturbance by humans. Therefore, their classification, the study of composition, and the monitoring of their structural changes are particularly important. A phytosociological survey of the supralittoral and upper sublittoral vegetation of the South West Baltic Sea revealed eight phytobenthos communities with two variants comprising 35 taxa of macrophytes (18 taxa of Chlorophyta, 13 taxa of Rhodophyta and four taxa of Phaeophyceae, Ochrophyta). Five of the eight communities were dominated by Ulvales (Ulva intestinalis, Kornmannia leptoderma, and three Blidingia species), the other three by Fucus vesiculosus. Most Fucus vesiculosus-dominated communities contained U. intestinalis and U. linza as subdominants. Only one of the communities had until now been described as an association ( Ulvetum intestinalis Feldman 1937). The syntaxonomic composition of the investigated vegetation includes both phytocenoses with the domination of green algae ( Ulvetum intestinalis Feldman 1937 and communities of Blidingia marginata, unidentified Blidingia spp. and Kornmannia leptoderma), as well as a number of communities dominated by Fucus vesiculosus. Mainly boreal Atlantic species and cosmopolitans make up the bulk of the species in these associations