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Responsible use of chemicals

Responsible use of chemicals Chemical dosing in areas such as swimming pools or waste water treatment demands absolute reliability and accuracy.

In swimming pools, suspended solids are removed by the pool water filtration system.  If these substances are too small, they pass through the filter and get back into the pool. The tiny particles cannot be filtered without additional measures. A common measure is the use of flocculation. This process causes the tiny particles to clump together, to become larger ones, which can then be trapped by the filter.

Aluminium sulphate is commonly used as a flocculant. This chemical is classified in the dangerous substances directive as "Harmful to health and mildly hazardous for water". A surplus when dosing must therefore be avoided. Due to the good electrical conductivity of aluminium sulphate, a magnetic-inductive flow measurement is the perfect method. The Kobold MIK flowmeter detects the smallest amounts of the chemical and ensures reliable monitoring of the Al2(SO4)3 dosage. The materials used - PVDF and tantalum - are completely resistant to the reagents involved and have proven themselves in long-term usage.

Despite the MIK's small and compact design, it offers a variety of features that will make your process safe and simple: analogue signal output for connection to a PLC; switching and pulse output for control of pumps, valves, alarms; independent counting; and batching function.

Phosphate precipitation
Careful dosing and monitoring of chemicals is also important in waste water treatment plants in areas such as phosphate precipitation. By addition of Iron Chloride (FeCl3) in the aeration basin, the phosphates dissolved in excess waste water are chemically mixed with sludge flocculants and transferred with sludge to the sludge treatment stage. This process reduces phosphate concentration in our waterways and therefore minimises the potential for abnormal algae growth, and the detrimental effect for the aquatic eco-system.

As an overdose of Iron Chloride leads to a massive pollution of water, is harmful to humans and pollutes the environment, a completely dependable method of process monitoring is paramount. A continuous flow measurement of the dosing chemical with a direct data connection to the process control system guarantees you maximum safety, so that possible errors are not just discovered during sample taking, when it's too late.

Kobold's MIK magnetic-inductive flow meter, again offers an optimal and economical solution. Complete with a direct mounted transmitter with stainless steel housing, the device forms a compact yet robust unit, ideal for fitting inside cramped control cabinets. It allows detection of very small dosage amounts from 10ml/min. With an analogue 4-20mA signal (or optional pulse output) the MIK continuously communicates the measured values to the process control system, so that it allows immediate response to the latest process conditions. This increases efficiency, saving cost in the amount of Iron Chloride required to achieve phosphate removal, and protection of the environment. It also improves safety allowing automated monitoring and dosing even at unmanned plants.
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