February 2013 – Piacenza

This sports center is a complex consisting of a gym, changing rooms, showers and two pools of different sizes: one large, 520 cubic meters, and a smaller one. The complex uses well water, to control the limestone uses a water softener, for the reduction of the bacterial load uses chlorine.

The main objective to be reached consisted in containing within the terms of the law (<0.4 mg / l) the amount of combined chlorine of the largest pool for which, considering also the dimensions of the pool water recirculation pipe, It is decided to install an electronic unit for diam.160. However, given the availability and openness of the property of the plant, a series of tests consisting of repositioning the unit was agreed upon to see what could be achieved.

On 20 February 2013 the 5 ml unit was installed downstream of the filters and one meter from the pumps. Prior to commissioning the device, the following measurements were made:

  • Combined chlorine 0.58 (detected by the automatic chlorine doser)
  • Recirculating water temperature 28.6 ° c.
  • PH 7.19
  • Hardness 41 degrees French
  • Conductivity 872

After a week the results obtained were as follows:

  • The quantity of flocculant is halved
  • The number of counter-washes has been halved
  • Visible increase in water clarity:

On March 3, the technician moved the unit before the heat exchanger: in a week the result was the clogging of the exchanger due to the detachment of the material (limestone and bio film) formed previously on the pipe walls. This demonstrated the effectiveness of the anti-scale technology.

However, the main objective remained the decrease in the combined chlorine so that on 14 March the unit was repositioned on the pipe at the outlet of the compensation tank, at about 10 ml from the delivery pump to the filters.

After a week the amount of chlorine injected was reduced by 20% and after another week by a further 10%.

Since the quantity of chlorine injected is a function of free chlorine in the water, it became clear that if there was more chlorine in the water this had to come from other sources, ie the combined chlorine that was decomposed by the technology used in free chlorine and organic material; the latter was flocculated and stopped by the filters.

The last repositioning was made by returning the device to the initial position with the following results certified by the attached analysis laboratory

  • Free chlorine 0.90
  • Chlorine amines (combined chlorine) 0.35

The automatic dosing instrumentation of chemical products, supplied and calibrated by the same supplier, continued to give different data all the time and it was not possible to have a comparison with the supplier.

Our analysis results have been confirmed by two different analytical laboratories that are not connected to each other.