Technical note

How to size an electrochemical descaling system: two inputs

Going one size up buys the wrong machine. Give us the tower rated flow and four make-up water numbers, and you get a selection report with assumptions stated.

Sizing is not "choose one size up"

In industrial equipment the safe habit is to go one size up. For electrochemical cooling water treatment that habit buys the wrong machine: oversized, the side-stream flow no longer matches the actual scaling load and the current density and operating strategy both have to be re-tuned; undersized, cycles of concentration cannot be raised and the investment does nothing.

Sizing depends on exactly two inputs: your circulating flow and your make-up water quality.

1. Match the cooling tower rated flow

Our models are named after cooling tower rated flow, so a tower model number is enough — no unit conversion needed:

• JT-ECT-330: 297–363 m³/h circulating flow (20 m³/h side-stream);
• JT-ECT-500: 450–550 m³/h (30 m³/h side-stream);
• JT-ECT-1000: 900–1,100 m³/h (60 m³/h side-stream).

With two tower groups, use the combined flow (e.g. two groups totalling 330 m³/h take one JT-ECT-330). Above 2,000 m³/h, two systems are configured.

2. Make-up water quality sets the current and the cell size

A 330 m³/h system with 80 mg/L make-up calcium hardness and one with 200 mg/L need completely different descaling duty. So we ask for four numbers:

• Calcium hardness (mg/L as CaCO₃);
• Total alkalinity (mg/L as CaCO₃);
• Chloride (mg/L);
• TDS or conductivity.

From these we calculate the mass balance — how much calcium must be removed — then convert to current and electrode area using Faraday's law to fix the cell size and operating strategy.

3. Site conditions decide whether and where it can be installed

The unit is an outdoor skid; no dedicated plant room is needed. On site you need:

• Side-stream tapping points — a branch off the circulating main with a return point;
• Footprint and maintenance access — the skid outline and footprint are given in our skid arrangement drawing (including access for maintenance and piping);
• Power: 380 V / 50 Hz;
• Compressed air: 0.4–0.6 MPa (a portable compressor is optional where no air supply exists);
• Blowdown connection to the plant drainage for periodic desludging.

Confirming these five items on site normally takes half a day.

4. What you receive

Our approach is that everything can be checked item by item, so what is delivered is not a brochure:

• Selection calculation report — recalculated from your make-up water: mass balance, Faraday calculation, equipment specification, energy consumption, applicable conditions and the assumptions used;
• Shop drawings — assembly, parts, piping, electrical and instrument index;
• A machine that can be checked item by item — drawings, calculation report and inspection criteria correspond one to one.

Energy figures are given on the same basis: descaling power consumption about 3.01 kW·h/kg CaCO₃ (operating basis; 2.47 at design condition), and installed cell power about 3.0 / 4.2 / 7.5 kW for the 330 / 500 / 1000 models (excluding pumps).

5. Next step

Send us the cooling tower model (or circulating flow) and the make-up water analysis and we will produce a first-pass selection. Incomplete data is fine to start with — we will tell you which item is missing and how to obtain it.