In this issue of Process Heating, we have a great line of articles that cover a range of process heating issues. Here’s a quick rundown of each.
  • Electric Thermal Fluid Heaters. Electrically heated thermal fluid systems are extremely useful for heat processing applications, but regular contributor Jay Hudson, P.E., cautions that the user should understand what’s “inside the box” when specifying and purchasing this equipment. In this installment of his six-part series on specifying a thermal fluid system, Hudson, who is president of a consulting firm, J.G. Hudson &Associates, based in Salisbury, N.C., provides an overview of the general types of equipment available as well as the details of construction to look for.
  • Multi-Zone SCR Power Control. By using multiple zones of heat control, you put the heat where it is needed most. So says George A. Sites, director of engineering at Ametek HDR Power Systems, Columbus, Ohio. Sites describes applications that lend themselves to multi-zone control as well as those better suited to single zones of control. For those applications that suit multi-zone control, however, the method provides a sophisticated means of managing your process equipment.
  • Heat Recovery Using Plate Heat Exchangers. Though in the past, many processors regarded heat recovery as not worth the capital expenditure, with today’s high energy costs, they’re taking a second look, according to Cheryl J. Shoemaker, a senior application engineer with APV North America in Getzville, N.Y. Shoemaker notes that plate heat exchangers designed for heat recovery can be specifically configured to meet the duty, taking into account the product characteristics. Heat recovery even is possible with two different products or with uneven flows. What is key, Shoemaker says, is capturing the heat before it is lost.
  • Functional Safety for Instrumented Systems. The global importance of safety-integrity levels (SILs) has grown substantially in the oil/gas, petrochemical and other process industries over the last 10 years. However, for many end users, systems integrators, and even product vendors, SIL is still a somewhat ambiguous concept that often is misinterpreted and incorrectly implemented, say engineers from General Monitors Inc., Lake Forest, Calif. Intended as a primer on SIL, the article notes that a safety instrumented system (SIS) is designed to prevent or mitigate hazardous events by taking a process to a safe state when predetermined conditions are violated.
  • Equipment Overview on Dryers. Rounding out the lineup of feature articles this month is our annual bullet chart on dryer manufacturers. This comprehensive selection guide can ease the dryer specification process by identifying manufacturers with the experience you desire. Also offered online at, the guide is a year-round reference worth retaining.
            Consider keeping these feature articles around your office for future reference. And when you’re out of the office, remember that these articles and more are fully searchable at using BNP Media’s Google-powered search function.

Linda Becker
Associate Publisher and Editor