British Sugar


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Introduction

ACWA has completed a turnkey contract to design, manufacture, install and commission water treatment system to provide ultra pure water for British Sugar’s 47MW Combined Heat and Power plant in Bury St Edmunds.

Description

Pretreatment
Borehole water enters a break tank from where it is pumped through multimedia iron removal pressure filters before being dosed with acid to reduce alkalinity. A 5 micron guard filter is employed before the water enters the filtered water break tank.

  Feedwater Post RO Post Mixed Beds
Conductivity (ms/cm) <1000 <25 <0.1
Silica (mg/l) 12 <0.5 <0.01
Sodium (mg/l) 4.5 <3 <0.005

Reverse Osmosis
From the pretreatment process, water is pumped to a single pass RO filtration system, designed to provide permeate of 10-20mg/l TDS for feeding to the mixed bed units. The plant is installed with five pressure tubes each containing five high rejection RO membranes, and anti-scalant is dosed in the feed line to the plant.

Demineralisation
The duplex 15m³/hr mixed bed demineralisation system removes the remaining dissolved contamination and produces a product of extremely high purity. Aspermeate passes down-flow through the mixed resin beds, the process provides a simultaneous cation and anion exchange to produce high purity water.

Mixed Bed Regeneration
As the resin becomes exhausted there is a reduction in the quality of the treated water and the bed has to be regenerated. The regeneration station is mounted on the same skid as the mixed bed columns.

Polishing
Whenever the demineralised water tanks are full, the RO plant and degasser shuts down automatically . The demineraliser feed pumps continue to operate, using actuated valves to shut off the suction from the degasser sump whilst opening a valve to allow suction from the base of the demineraliser storage tanks this then polishes the storage tanks. A unique feature of this plant, is that the operator is able to select high flow polishing and run both demineralisation tanks in parallel at 30m³/hr.

Project Details

Client: British Sugar

Industry: Water Treatment

Application: Provision of ultra pure water for use in power generation

Technologies