While perhaps not quite as frightening as the famous Alfred Hitchcock shower scene, just imagine the shock of stepping into a hot shower, unwrapping your favorite bar of soap and discovering that it is already dirty. It can happen.

That is because soap contains glycerin, which brings with it important moisturizing properties. During the manufacturing process, glycerin is added to the soap formulation before it goes to final production. The temperature control during manufacturing must be precise, with little margin for error. When the temperature is not controlled properly, the soap can turn brown and even form brown specks — small but still very much noticeable. That is hardly the 99 and 44/100ths percent pure that a good soap needs to be.

The Advantages of Upgrading Your Filtration Systems

Industrial processors can experience significant benefits by filtration. Some typical applications are described below:  

  • In papermaking and other process applications, many processors incorporate prefilters upstream of expensive membrane filtration systems. The prefilter — typically either a bag or clean-in-place (CIP) filter — removes suspended solids that could prematurely foul or damage the membrane system.
  • Adding a filtration system before a liquid passes through spray nozzles offers several benefits. Filtration prevents solid particles from reaching the nozzles, preventing unnecessary wear on the nozzles. Removing solid particles also prevents passage of debris through the nozzles and into the process or on the products. Spray patterns and process quality are improved, and defects are reduced.
  • A knife manufacturer was able to use well water instead of city water to cool its molding machines by adding a stainless steel CIP filter. In order to make the switch, the well water had to be filtered to a level as clean as or cleaner than the city water. The CIP system met the companys water-cleaning requirements and allowed it to save $25,000 annually in city water costs.
  • In plastics molding and extrusion operations, cooling water readily picks up small plastic particles, lime scale and airborne particulates — especially if the cooling water is kept in a central sump. Removing suspended solids from this cooling water results in decreased maintenance, downtime, equipment wear and utility costs. Consequently, cycle times and production rates remain high while rejects are minimized.

For one of the world’s largest suppliers of bar, detergent and body soaps, meeting that lofty purity goal is imperative to success. Supplying virtually every type of soap made, the company sees some 25 different brands of soap rolling down its production line on any given day. With multiple brands and products at stake and high quality standards to live up to, the company remains focused on creating an efficient production process.

Before its recent plant and process upgrade, the company often had to reroute soap into the assembly line to remove the brown haze and specks caused by the improperly handled glycerin to ensure that quality objectives were always achieved. The rerouting was necessary but inefficient, expensive and time-consuming. Additional labor also was required, resulting in added costs and downtime.

To address these process limitations, the company upgraded its filtration system as part of streamlining the manufacturing operations.

Many manufacturers consider upgrading existing filtration systems or adding new filtration systems an unnecessary expense. This is understandable: The solids in process fluids only occasionally cause catastrophic failures and time-consuming inefficiencies. Installed costs must be weighed against operating costs. However, the hidden costs created by contaminants are significant. Their ongoing carrying costs render the expense of removing and replacing the filtration system modest and one that can be recovered quickly. With the proper systems in place, significant benefits can be achieved.

Selecting filtration equipment is the combined result of many considerations. In addition to removing undesirable material from a liquid stream, the filtration method selected must also satisfy other requirements:

  • Is continuous flow a requirement of the application, or can the filtration equipment be operated intermittently?
  • Is worker exposure to the process liquid during filter cleaning or replacement a problem?
  • What are the waste disposal costs?

These and other factors were considered by the company when choosing a new filtration method for its operations.

Before its recent plant and process upgrade, while the final product eventually met purity goals, the soap giant wanted to clean up the process. As a part of the revamped process, the soap maker installed a DCF-800 automatic self-cleaning filter from Eaton’s Filtration Division for a 90-day trial run.

The filter performs a self-cleaning action that does not interrupt production or impede flow rate. The self-cleaning action mechanically scrapes collected debris from the filter screen with a disc that moves up and down the screen, parallel to the liquid flow. Collected debris then is automatically purged from the collection chamber at the bottom of the filter. This self-cleaning action provides the filtering under continuous demand. Because the screen is cleaned continuously, a consistently high flow rate is maintained. Uninterrupted filtering also helps ensure consistent temperatures — a feature essential to meeting quality objectives at the soap maker’s plant.

Before the 90-day test was completed, the soap company was already washing its hands of the brown mess that had caused so much product rerouting. The company has since ordered two additional filters.

As the trial demonstrated, careful consideration and testing when choosing a liquid filtration system will offer many potential benefits. many potential benefits. A wise filter selection can:

  • Minimize process downtime.
  • Reduce waste disposal costs.
  • Limit worker exposure to the process liquid.
  • Reduce maintenance time and expense.
  • Improve product quality.

Therefore, it is important to review all the available filtration options and identify potential areas where adding or upgrading filtration can provide cost savings.

 As a result of testing this new approach, the costly rerouting of soap will soon be virtually eliminated. While, it is still too early to gather a measurable return on investment, based on the results of the trial, the number of bars of soap that the company produces, and the cost to rework an out of spec product, payback is likely to be short term.