Industries

As with most major process plants, refineries and petrochemical plants periodically need to shut down the entire plant or major portions of it for major maintenance activities. These time periods are referred to as ‘turnarounds’ and are time periods of intense activity. Once the plant shuts down, a considerable amount of money is being spent without any revenue being generated.

A Gulf Coast chemical manufacturer of oxo derivative and intermediate products including alcohols, polyols, carboxylic acids, specialty esters, and amines experienced a failure in a critical chiller that shut down its entire Gulf Coast plant. A plant manager estimated a potential financial loss of over $1,000,000 each day the plant was down. The incident occurred over the weekend and there was great concern that locating a replacement chiller with sufficient capacity would be challenging.  

Plastics processors are looking to advanced process cooling equipment to lower operational costs, and in many cases, improve the quality of products and achieve sustainability goals. But it’s more than just a matter of finding a better mousetrap and putting systems to work. Instead, it requires a keen understanding of the processes involved, followed by the design and installation of advanced technology in combination with the right process cooling systems matched to a company’s goals.

Controlled cooling is an essential part of manufacturing polyethylene stretch film. The process starts with granulated polyethylene raw product with very low strength, and develops thin, clear, strong film used in a variety of applications.  It does this by melting, extrusion, “casting” and winding.  See Figure 1 for a typical system diagram.  “Casting” is forming and cooling at the same time. The extruded polymer is stretched and cooled on large, chrome-plated rollers with cooling water flowing inside. Thinner film is for manual use, like wrapping around food products.  Thicker, stronger product is made for machine use, like automatically wrapping pallets of concrete bags.

Intelligent process cooling describes an approach to cooling in beverage production and packaging that moves beyond evaporative cooling towers and the use of traditional central chiller systems that rely on ammonia as a refrigerant. Unlike traditional methods, it intelligently matches process cooling systems to individual cooling loads without an evaporative process or the use of ammonia to gain verifiably better results in energy efficiency, water use, and safety.

Long known as water hogs, resistance welders are widely used in factories that manufacture products made from sheet metal and wire. Sub-categories of the resistance welding process include spot welding, projection welding, seam welding, butt welding and flash welding. An adequate flow of cooling water is one of the most important variables of the resistance welding process, and the typical machine requires 2 to 3 GPM of water per cooling circuit.  

This major mill complex upgraded their compressed air system and thereby eliminated $500,000 in annual rental compressor costs, reduced annual cooling-water costs by $500,000, and reduced electrical energy costs by $135,000 per year.

Air compressors are very effective heaters. Over eighty percent of the energy input from the motor is converted into compression heat. That heat must be rejected from the compressor package in a way that maintains a variety of temperatures in a reliable manner. The laws of physics demand that the air temperatures go up with compression.

No matter what your application, there is a single formula for determining the size of chiller you need. There also industry-specific, rules-of-thumb for chiller sizing. These may vary depending upon the application. These guidelines and formulas may be used for sizing chillers for plastic process cooling applications.