Reference
GKL11/3/8
Title
Photograph of P250L recorder at British Sugar Corporation, Spalding.
Date free text
1981
Production date
From: 1981 To: 1981
Scope and Content
Caption:
'Clearspan P250L multipoint chart recorders and thermocouples from Kent Industrial Measurments are helping to ensure effecient boiler operation at the Spalding factory of the British Sugar Corporation.
Heat, supplied in the form of steam, is of prime importance to the factory as the basic process of sugar production is first the diffusion of sugar from shredded beet into hot water, and then the evaporation of a considerable quantity of water from the resulting juice.
Two boilers are used to generate the steam; one is coal-fired and the other oil-fired. Each works with an economiser, which uses the hot exhaust gas from the boiler to pre-heat the water feed.
Both boilers are moitored and controlled by Kent instrumentation and produce a total of172,000 pounds of steam per hour at 400lb/in2. The outputs of the boilers are fed to the sugar process plant via a turbine, which generates all the factory's electricity.
A six-point version of the Kent Clearspan P250L recorder is installed with each boiler to monitor its performance. The instrument traces the temperatures of the water and steam into and out of both the boiler and its economiser, and also the exhaust temperatures of the boiler and its economiser. Each temperature is sensed by a Kent thermo-couple and recorded on the 25mm wide chart to an accuracy of +/- 0.25 per cent span (500 degrees C).
The chart recordings clearly show any fall in the heat transfer effeciency of the boiler or econimoser due for instance to a build up of waste materials on the boiler tubes. The feed water temperature into the economiser is especially important. Warm condensate from the evaporation of sugar juice is used as the source of supply, but should its temperature fall to a critical value, the exhaust gasses in the economiser condense as sulphuric acid on the feed water tubes, causing rapid corrosion.
The chart recording made by the Clearspan P250L provides a permanent record of such adverse trends and enables their effect onn the condition of the boiler to be assessed during maintenance shut-down.'
Level of description
item