EPS vs. Acid Pickling Capital Cost Comparison

To compare the capital costs of a new EPS project and a new acid pickling project, the competing systems must have very similar output. Based on processing low carbon strip of 10mm (0.250″) thickness or less, we found that a push-pull hydrochloric acid pickling line utilizing 4 pickling tanks matched the output of a 2-Cell EPS Coil Line. Therefore, the capital cost comparison below is based on those two competing systems. 

The acid pickling line chosen is an actual operating line, not a model. It’s in North America, was supplied from a reputable equipment manufacturer, and is considered ‘service center duty’ because, among other reasons, it does not include a tension leveler. By contrast, EPS is a ‘tight line’ process with its uncoiler and recoiler providing the same overall tension as the entry and exit bridle rolls of a tension leveler found in ‘mill duty’ acid pickling lines. Therefore, to place the competing systems on equal footing, the cost of a tension leveling system must be added to the acid pickling line cost below.

4 Tank Acid Pickling Line

2-Cell EPS Coil Line

Equipment Capital Cost

While the selected four tank acid pickling line does not include a tension leveler, it is, nonetheless, a full-featured line. The cost data revealed that its total equipment cost is comparable to the 2 Cell EPS Coil Line. However, the lack of tension leveling in the acid pickling line must be rectified for to the equipment cost comparison to be accurate.

To do that, the cost of a bridle roll tension leveling system (customary for a line like this) was added to the cost of the acid pickling line. That adjustment escalates the total cost of the acid pickling line such that the 2 Cell EPS Coil Line equipment cost is 20% less than the adjusted acid pickling line equipment cost.

A tension leveling system cost is added to the acid pickling line.

Building Capital Cost

The acid pickling line has a crane-served area of 95.5 m x 24.4 m for a total area of 2330 m2 (25,040 ft2). The numbers for the EPS Coil Line are 55.2 m X 25 m = 1380 m2 (14,850 ft2).

If the acid pickling line requires 70% more space under crane as the EPS line does, it has a 70% higher building cost for that portion of the structure. At a construction cost of $1100/m2 ($100/ft2) – a reasonable number for an industrial building with foundations, columns and rails to support 50 ton cranes – that is a difference of $1,045,000 more for the acid pickling line building.

The acid pickling line requires 2X the building space of EPS.

Installation Capital Cost

We are confident of EPS Coil Line installation costs – we installed our own tension leveled EPS Coil Line  and supported installations at customer sites. For acid pickling line installation costs, we received valuable help from both acid picklers and equipment suppliers. The net result is an EPS line costs roughly 30% less to install than an acid pickling line of comparable output.

An acid pickling line  has more components to be installed: separate pre-wash and post-wash systems, bridle rolls for tension leveling, heaters, scrubbers and fume extraction systems, none of which are needed for EPS. And there is just more plumbing – valves, piping, filters, etc. – needed for an acid pickling line. 

EPS Coil Line installation costs are well understood.

Summary of Capital Cost Comparison

For pickling of low carbon coils up to 0.250”, EPS has the capital cost advantage over a tension-leveling push-pull acid pickling line of comparable capacity in each category:

  • 20% lower equipment cost
  • 30% lower installation cost
  • A $1.05 million savings in building cost

Combining these factors together, the EPS line capital cost is roughly 75% of the acid pickling line costs.

If you introduce high carbon, alloy steels, AHSS and silicon steels into the mix, the EPS capital cost advantage expands, because while the EPS line’s output would be lowered modestly for these grades, the acid pickling line’s output would drop dramatically (see details). Raising the acid line’s output back to parity would require additional acid tanks and more building space, while the EPS capital cost would increase only marginally.