Proving Energy Efficiency in Manufacturing Delivers Serious ROI. By Anoosheh M. Oskouian

Transcription

1 Proving Energy Efficiency in Manufacturing Delivers Serious ROI By Anoosheh M. Oskouian

2 Ship & Shore offers solutions and recommendations for effective methods to reduce energy consumption, lower operating costs through waste heat recovery and assists manufacturers in taking advantage of any rebates or incentive programs available. We will briefly describe some options and benefits of our custom designed waste heat and energy recovery systems capable of capturing hot exhaust from combustion produced during various manufacturing processes and redirects to other areas of production to save and re-use energy. Don t hesitate to call us at to get started in the right direction. 2

3 TABLE OF CONTENTS Waste Heat Technology...4 Optimizing the Manufacturing Process...5 Capturing Heat Clean Tech Options Regenerative Thermal Oxidizer Economizer Heat Exchanger...6 Maximize Energy Savings...7 Case study...8 Conclusion...9 CALL OUR EXPERT TO GET A FREE INITIAL FREE INITIAL CONFIDENTIAL CONSULTATION BASED ON YOUR NEEDS

4 Waste Heat Technology For manufacturers, there are many existing recovery technologies already well-developed and technically proven that provide significant opportunities for improving industrial energy efficiency through waste heat recovery. But before beginning a waste heat recovery project, it is essential to identify all potential sources of accessible waste heat, type of recovery technologies available for these sources, and, most importantly, how the recovered waste heat energy can be utilized. After conducting a survey of plant equipment utilizing large quantities of electricity and/or natural gas, a preliminary plan for capture of waste heat energy should be developed. That way, the essential heat transfer projects can be identified and a cost analysis performed to identify the feasibility of potential projects. 4

5 Optimizing the Manufacturing Process Capturing Heat Captured industrial waste can either be reused within the same process or transferred to another process. For example, thermal oxidizers, ovens, and furnaces all exhaust hot products as a result of combustion. The hot exhausts products can then be fed to air-to-air heat exchangers to provide preheated air to combustion equipment such as boilers, furnaces and ovens, or used for space heating and drying/curing room heating. Clean Tech Options Regenerative Thermal Oxidizer Alternately, regenerative thermal oxidizers (RTO) can also be used by air-to-liquid heat exchangers to heat water, oil or other process fluids. Improving equipment efficiency through preventive maintenance and tuning must also be considered. Economizer Next, steam boiler and hot water boiler efficiency can be improved by capturing waste heat through the use of economizers, condensing economizers and blowdown heat exchangers. By preheating the boiler feed water, the amount of energy required to heat the water to operating temperature can be reduced significantly. Commercial building account for 36 percent of all US electricity consumption and cost more than $190 million in energy every year. 5

6 Heat Exchanger Finally, heat exchangers can also be used to transfer heat of combustion from thermal oxidizers and furnaces to drying ovens, curing rooms and for space heating. By doing this, the recovered heat can replace fossil fuel energy that would have otherwise been used. Such methods for recovering waste heat can help facilities significantly reduce their fossil fuel consumption and greenhouse gas emissions, as well as reduce associated operating costs. In addition, according to the European Commission, many ceramic dryers now use hot air recovered from the cooling zones of tunnel kilns, usually supplemented with hot air from gas burners - so the layout of the plant is very important. In particular, low temperature excess heat can only be managed usefully if the length of the pipes i.e. the distance between excess heat generation and use is very limited. In any case, suitable heat insulation of the pipes is required. Significant energy savings have been achieved in this way. Finally, heat recovery should be considered only after the kiln has been optimized. This minimizes the heat available for recovery, but is the most energy efficient route. Also, these tips, from Tangram Technology Ltd., can help maximize energy savings: 6

7 S&SE HAS ASSITED CLIENTS IN RECEIVING OVER 5.5 MILLION DOLLARS IN UTILITY CASH REBATES & INCENTIVES Maximize Energy Savings The United States industrial sector accounts for approximately one third of all energy used in the United States, consuming approximately 32 quadrillion Btu (1015 Btu) of energy annually and emitting about 1,680 million metric tons of carbon dioxide associated with this energy use. Efforts to improve industrial energy efficiency focus on reducing the energy consumed by the equipment used in manufacturing (e.g., boilers, furnaces, dryers, reactors, separators, motors, and pumps) or changing the processes or techniques to manufacture products. A valuable alternative approach to improving overall energy efficiency is to capture and reuse the lost or waste heat that is intrinsic to all industrial manufacturing. During these manufacturing processes, as much as 20 to 50% of the energy consumed is ultimately lost via waste heat contained in streams of hot exhaust gases and liquids, as well as through heat conduction, convection, and radiation from hot equipment surfaces and from heated product streams. In some cases, such as industrial furnaces, efficiency improvements resulting from waste heat recovery can improve energy efficiency by 10% to as much as 50%. 1 Captured and reused waste heat is an emission free substitute for costly purchased fuels or electricity. Numerous technologies are available for transferring waste heat to a productive end use. Nonetheless, anywhere from 5 13 quadrillion Btu/yr of waste heat energy remains unrecovered as a consequence of industrial manufacturing. 7

8 Case study A recent project completed by Ship & Shore Environmental for a coating operation, one which is applicable to ceramics manufacturing, included process exhaust recirculation to reduce the heating costs of the customer s wash system, which subsequently decreased the temperature of the volatile organic compound (VOC)-laden air stream handled by a regenerative thermal oxidizer. This project was achieved by installation of multiple air-to-water heat exchangers A 400 F oven exhaust was fed to an air-to-water heat exchanger, for two purposes. 1. To heat water for a plant parts cleaning operation. 2. To reduce outlet temperature of the oven exhaust, so that common spiral-wound galvanized duct could be used for transfer of the solvent-laden air stream to the regenerative thermal oxidizer, which was required to meet air pollution abatement permit conditions. By using spiral-wound galvanized ducting instead of using welded solid construction carbon steel ducting a significant cost savings resulted. Through a local utility incentive/rebate program, Ship & Shore Environmental assisted the end user with the application for an energy-saving process improvement measure. The project was pre-qualified for $145,000 rebate for the heat exchanger project and energy-efficient RTO. In addition, a $95,000 cost savings was realized due to the change in material selection for the ducting installation. Specifics include: Recirculation heat exchanger - Therm kw savings $0.07 per kwh saved Make-up up water heat exchanger - Therm kw savings $0.07 per kwh saved TRO - Therm kw savings $.32 per Therm saved 8

9 Effective Energy Recovery Solutions Expand & Upgrade with Utility Cash Incentive Programs In the end, every manufacturing facility has unique requirements that must be considered carefully. Many facilities can benefit from an energy consumption assessment, which includes recommendations for heat recovery or other energy reducing measures such as equipment tune-ups and repairs to steam lines, steam traps, compressor systems, HVAC systems and other high energy consuming equipment. As you can see from the above case study, the potential savings and impact from improving industrial energy efficiency through waste heat is a worthwhile endeavor. We are confident that our knowledge and experience can become a valuable asset when it comes to meeting air quality rules. We have experience negotiating with many different air quality agencies from EPA to the local air quality agencies, as rules vary throughout the U.S. and Canada. When a manufacturer needs help with air pollution abatement and compliance, our team can provide valuable assistance with many of the different aspects involved. CALL OUR EXPERT TO GET A FREE INITIAL FREE INITIAL CONFIDENTIAL CONSULTATION BASED ON YOUR NEEDS

10 Reference 1. US Department of Energy,Waste Heat Recovery: Technology and opportunities in U.S. Industry retrived at 10