Plant Services - November 2007 - (Page 58)

EFFICIENCY Compressors domestic hot water, space heating or both. There’s a tradeoff to be considered if the refrigeration system uses floating head pressure. Under conditions of low ambient temperature, the demand of the heat reclaim system might require the condensing pressure to be raised to supply more heat. This can reduce or eliminate the head pressure reduction benefits during certain cold weather periods. Advances in supermarket refrigeration system technology are increasing the potential for heat recovery. Because of the mandate to eliminate ozonedepleting refrigerants, designers are exploring secondary fluid loops. These loops are used for cooling display cases and rejecting heat from the system. The secondary heat rejection loop allows easy integration of direct heat recovery or heat-pump heat recovery. In direct recovery, the heat rejection loop is routed through the HVAC air handler on its way to the cooling tower. In indirect recovery, heat pumps on the heat rejection loop extract heat to provide space or water heating – similar to a water source heat pump system. In a similar fashion, refrigeration compressor (and air compressor) heat recovery can be integrated with geothermal heat pump systems. The geothermal loop is used as the heat sink for the compressors. During the cooling season, the loop rejects heat to the ground. In the heating season, the heat recovered from the compressor supplements the heat extracted from the ground by the ground source heat pumps. What gets in the way? Heat recovery is one of the most frequently recommended energy cost reduction measures (ECRM), yet it’s also one of the least often imple- mented. The biggest reason is that as a retrofit, heat recovery from compressors or any other source usually isn’t a plug-and-play proposition. Often, there’s some custom engineering involved in sizing the components, setting up the controls and optimizing the integration of the heat recovery with the overall commercial or industrial operation. That’s why heat recovery should be considered early on in the design of a new plant, process or building. That way, the engineering, component selection and controls are part of the initial design effort. This is more cost-effective at the design stage because only incremental costs are involved – there’s no labor or expense for equipment or process downtime, or for disassembly or demolition. Considering heat recovery in the initial design helps ensure that the benefits of this cost-effective technology are realized. BenJ.Sliwinskiisthetechnicaldirectorof theSmartEnergyDesignAssistanceCenter (SEDAC)locatedattheUniversityofIllinois inUrbana-Champaign.Hecanbereached through the SEDAC Web site at www. sedac.org. Our repeat customers are few and far between. And frankly, we’re pretty happy about that. More resources at www.PlantServices.com/thismonth ••• • Compressors calcs – “Benchmark your aircompressor” •Ductdesign–“HVACandindustrialven tilationductdesign” • EXcalcs–“WhatdoesMotherNature H sayaboutyourheatexchangers?” • Heat of compression – “What does Mother Nature say about cooling hot air?” • Condensate rate – “What does Mother Naturesayaboutcompressorcondensaterates?” •Chillertips–“10tipsforimprovingchill erefficiency” •Determinantsofperformance–“Apply ingthepressure” •Geothermal-basedHVAC–“Betterthan agoldmine” We’ve got a long list of satisfied customers. But as happy as they are, it will be a long time before we hear from them again. It’s because they’re using HammerTek’s Smart Elbow® in their conveying system. Other elbows wear out fast and need to be replaced often. We’ve seen it with pretty much anything transported through conveying systems. But the Smart Elbow® relies on deflection — not impact — eliminating the impact-related problems with virtually every other conveying elbow. Take advantage of our free trial* and see for yourself why the Smart Elbow® is built to endure. *please call for complete details. P.O. Box 416, Landisville, PA 17538 • 888-82-ELBOW • 717-898-7665 • Fax 717-898-9279 www.hammertek.com/impo • email: elbows@hammertek.com 58 www.PLANTSERVICES.com November 2007 Made in the USA http://www.sedac.org http://www.sedac.org http://www.PlantServices.com/thismonth http://www.hammertek.com/impo http://www.hammertek.com/impo http://www.hammertek.com/impo http://www.PLANTSERVICES.com

Table of Contents Feed for the Digital Edition of Plant Services - November 2007

Plant Services - November 2007 Contents New Tools Letters Let Us Know Where to Put the Gas Up and Running How are you Fighting Crisis? What Works Why is the Best Practice Transfer so Hard? Who are you Going to Call? Chained to Power Mobile Mindset Making Money in the Lube Lab Grabbing a Moving Target Bagging the BTUs Keeping Mellow Preserving Health and Safety The Power of Reliability Excellence

Plant Services - November 2007

For optimal viewing of this digital publication, please enable JavaScript and then refresh the page. If you would like to try to load the digital publication without using Flash Player detection, please click here.