Mechanical Insulation – Revisited

 

By
Gerard Hillenbrand, P.E.

That was the subject of ASME’s Met Section Technical meeting on June 17th 2008 held at Con Edison Headquarters on 14th Street in Manhattan. This was the second time in the last three years that our section has presented a technical meeting on this important subject for the national objective of reducing carbon emissions and energy consumption. Licensed professional engineers who attended this meeting earned one PDH toward fulfilling their continuing education requirements as mandated by the N.Y. State education department.

The speaker at this technical presentation was Ronald L. King, a mechanical engineer who now functions as a consultant for the national insulation association, a $9 billion annual business entity representing more than 4000 insulation contractors and almost 80% of the labor in the insulation industry. Mr. King, who first addressed the Met Section on May 16th, 2006, is a specialist in the manufacturing and installation of insulation materials and a former President of this association, which was founded 55 years ago.

To a certain extent mechanical insulation is a forgotten technology, largely invisible, and taken for granted while being relatively low on the engineering complexity scale. Furthermore, industry studies show that frequently insulation, once properly installed initially, has been allowed to deteriorate as a result of lack of effective maintenance. Energy costs can triple or quadruple under these conditions where hot flashes, cold spots and excess gas emissions from unprotected piping compromise thermal efficiency, acoustical parameters, and personal operator safety, as well as corrosive condensation on expensive and essential equipment.

It goes without saying that process insulation is absolutely essential to reduce energy costs and achieve environmentally desirable performance. It is well known that energy costs are constantly increasing even when alternative fuels such as wind, solar, and ethanol are factored in. Government regulations continually track residential heating and lighting losses, but not those of industry. For example, inspection studies show that 3 to 5 years after installation, 10 to 30% of insulation on hot piping is missing or damaged. In petrochemical plants the figure is 21% of average, and in chemical processing plants the corresponding figure in 19%. These studies also show that heat loss from piping that is not insulated is ten times that from insulated piping. Similarly, heat loss from damaged piping is five times that of insulated piping. One specific analysis of an oil refinery showed that energy losses were equivalent to 5800 barrels of oil per day. At $130 per barrel costs, the refinery losses reached $750,000 per day due to deficient insulation. A recent assessment of processing plants by the U.S. Department of energy revealed that insulation deficiencies caused energy losses averaging 51 to 54%. Correcting these deficiencies could result in $658 million in energy savings and 5.1 million tons reduction in CO2 emissions. Similar savings at a natural gas plant could total 54.5 trillion BTUs. In view of these staggering statistics, the costs of proper insulation installation are minimal. For example, the pay back period for such usage averages about six months. Studies show that 84% of insulation installations produce a return on investment in less than one year, 14% of installations produce a return in three years or less, and 2% of installations require five years or less.

Mr. King then proceeded to identify many case studies in which process savings were as high as $1.5 million per year. Included in these studies were steam power plants, paper mills, steel mills, chemical plants, and rubber manufacturing plants, breweries, dairy farms, and food factories. One healthcare facility lost 45% of energy costs due to insulation deficiencies in it s HVAC system. Another government building experienced a 40% reduction in energy costs when insulation was upgraded. A plywood manufacturing plant achieved similar savings when insulation was added to all process controls.

Modern environmental groups have enthusiastically embraced the need for insulation installation and maintenance to assure reduction of emissions and improvements in indoor and outdoor air quality. The prominent green building movement has continually advocated the use of sustainable design technology of which insulation is a vital component. The American Institute of Architects has promoted its 2030-challenge program, which recommends 50% reductions in energy consumption in both new and existing buildings. Once again, insulation usage is a necessary part of this program. The broad acceptance of the global warming hypothesis by the scientific community has galvanized society toward achieving a carbon neutral environment within twenty years. Electric power generating plants will adopt carbon credit and trading techniques to realize these objectives. Of course, these goals cannot be achieved without suitable insulation provisions in both construction and maintenance.

The very favorable return on investment that accompanies the correct application of insulation is not the only compelling reason for its usage. Life cycle cost studies validate the value of insulation. Construction costs for process plants average from 20 to 30% of operating costs over one life cycle. The proper employment of insulation can extend operating life from 30 to 40 years. The life cycle of individual components can also be increased correspondingly. This includes properly insulating such equipment as valves, joints and inspection ports. For example, total valve insulation can produce energy savings of $412 per year per valve. Insulation gaps can cause excessive moisture condensation resulting in mold generation and corrosion necessitating pipe replacement at huge expense. The application of insulation to piping, conduits, ducts and process controls is not the only benefit provided by these materials. They commonly furnish area fire protections and protective suiting for operating personnel. These materials also have extensive weather proofing and vapor barriers.

Mr. King’s organization, the insulation manufacturers association, has published several resources for aiding engineers in their design efforts. For example:

  • The “MTL” Product catalog is an on-line library providing technical data on all forms and types of insulation materials. Updated periodically, this source provides complete product specifications on all insulation materials including the most advanced types developed in the last five years, such as duct wraps and liners, self-drying insulators, low conductivity types, and nano-plasiticity materials.
  • The monthly publication “Insulation Outlook”, a magazine with more than 10,000 subscribers. Attendees at this meeting had the opportunity to obtain a free subscription to this magazine.
  • The “3E Plus” software program which provides a systematic method for calculating the correct thickness of insulation materials to provide the appropriate reduction in heat loss, to maintain process control temperature, to provide safe insulation surface temperatures, and to control condensation. This program can also calculate the quantity of greenhouse gas emissions associated with insulation thickness, and conductivity specifications and data from all current ASTM publications, as well as guidelines from the National Institute of Building Sciences. The “3E” term stands for the energy, economic, and environmental savings achieved through the proper design of insulation materials. Attendees at this meeting also received a free copy of this computer program.

This technical presentation was a very informative example of the type of material continually available at our meetings. Please remember to join us next time, and contact www.insulation.org for answers to your technical questions.

 Posted by at 4:18 pm