VALVES & FLOW CONTROL
PRECISE MONITORING
BURKERT
FAST, CONVENIENT WATER QUALITY
MONITORING COULD HOLD THE KEY
Water is used in so many ways throughout
the food and beverage industry, even as the
final product, which means the quality of that
water needs to be carefully monitored. With
such an influence on the finished product,
precise water quality monitoring can provide
the key to consistent quality output, so is
it time to look at the next generation of
compact continuous analysis solutions?
Greg Wainhouse, UK Water Segment Manager
for Bürkert, looks at water usage within the
food and beverage sector, and the best
practical method of continuous monitoring
for various aspects of water quality as it
enters the process.
Water is an essential element in the
manufacture of food and drink, from washing
produce to being the main ingredient,
each application has different water quality
requirements. Having access to reliable, up-
to-date data on water quality parameters is
an important step in improving productivity
as well as the quality of the final food
products.
SOURCE MONITORING
In most cases, water will be supplied by
the local water authority, which has the
responsibility to provide a service within
certain parameters. However, demands on
the treatment plants, seasonal changes
and the age of the network can have a big
influence, and this means variability in the
quality of mains-supplied water.
It is possible for the local authority to be
unaware of an ‘out-of-consent’ incident until
it is reported by consumers, but for some
industrial customers, this notification will
have come far too late. Furthermore, water
authorities are required to add sufficient
levels of chlorine to reach the furthest points
of the network. This means that those closest
to the water treatment works may receive
some free-chlorine, which can damage
sensitive equipment such as reverse osmosis
membranes for example.
The alternative is a bore hole, usually on or
near the manufacturing site, but this source
can be affected by temperature, rainfall and
local agricultural activities, which means it
needs to be tested for quality at least every
month, preferably more frequently. On-site
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treatment should be looking to remove
sediment, dissolved iron, nitrates and
bacteria.
FILTRATION SYSTEMS
Whichever source is used, manufacturers will
employ a range of water treatment processes,
depending on their application. Carbon filters
can remove chlorine, biological contaminants
and flavours, while a sand filter will remove
iron. Ion-exchange processes are used to
soften the water and both pH and conductivity
monitoring can take place at this point.
Finally, filtration is used to remove unwanted
particles, organic matter and bacteria.
Depending on the quality of water required,
manufacturers may use ultra-filtration, nano-
filtration or reverse osmosis and each process
can be equipped with sensors for turbidity,
chlorine and pH to provide feedback on water
quality.
CAPTURING VITAL DATA
To resolve this situation, manufacturers need
an accurate but flexible system that can be
built around their application and connect
directly into their control infrastructure. Some
will only need pH and turbidity, while others
require a more comprehensive solution that
includes iron, chlorine, conductivity and
oxidation reduction potential (ORP).
However, capturing the data is just the first
step, validating it for accuracy and using the
data for positive process control also need to
be considered. To this end, calibration of the
sensors is an important step that may require
a certain amount of downtime and additional
expense.
MODULAR, FLEXIBLE
SOLUTIONS
There is an opportunity for food and
beverage manufacturers to use the latest
in sensing technology that has a proven
track-record in accuracy and simplicity. As a
compact and modular design, Bürkert’s Type
8905 Online Analysis System, offers a range
of benefits that make it cost-effective and
reliable for this purpose.
The Type 8905 offers a multi-channel, multi-
function unit capable of measuring pH, ORP,
conductivity, free chlorine and turbidity,
chlorine dioxide and iron. Several of the
measurements are conducted by compact
plug-in sensor cubes, offering ease of use and
convenience. The introduction of a chlorine
monitor is an important addition due to
its popularity in the disinfection process as
an effective microbicide, disinfectant and
sanitiser.
Bürkert has also developed an auto-cleaning
process for the sensor cubes that uses a
solution of clean, filtered water and mild
citric acid, primarily to flush the turbidity
sensor cube. The accuracy of the water
analysis equipment can be maintained using
a hand-held cleaning and calibration module
that connects to the Type 8905. This enables
operators to follow simple step-by-step
maintenance instructions and procedures for
using calibration fluids. All the while, the base
unit is constantly monitoring the process and
recording the necessary data.
www.burkert.co.uk/en