Improving Process Sustainability and Profitability for a Large U.S. Gray Iron Foundry (Electronic Poster Presentation)

Improving Process Sustainability and Profitability for a Large U.S. Gray Iron Foundry

Prashant Nagapurkar, Shyam Paudel and Joseph D. Smith, PhD.

Missouri University of Science and Technology, Rolla, Missouri, USA

Abstract

Energy savings and sustainability has been an important topic in many industrial processes.  Limited energy resources and increasing electricity prices make foundry processes less competitive in today's world economy.  For foundry processes, the energy costs generally represent 5-7% of the total sales. Most of the energy used in an foundry is directly related to melting and heat treatment operations.  Integrating heat and power systems in a foundry through waste heat recovery techniques can lead to energy reutilization that improves process sustainability and profitability.  The work presented here is an in-depth energy management analysis using Powersim^TM to identify potential energy savings through process optimization and advanced control strategies. A system dynamics model based on the interactions among the major energy intensive variables has been developed using Powersim^TM to estimate energy consumption. Our dynamic model estimates the monthly energy usage and its costs for a full calender year. The estimated energy consumption and its costs have been validated by comparison to the actual plant data obtained from the Mapleton foundry.

The average metal caster has a 2.4% pre-tax operating profit on sales. This profit is susceptible to fluctuating utility costs and process disturbances. Since foundry operates with very thin profit margins it is imperative to ensure that the foundry is running with efficient process control. Hence, advanced control strategies for the melters, dust collectors, fans and burners have been proposed and  implemented in the Powersim^TM model for optimum energy usage. Our results show that these control strategies along with waste heat recovery techniques could save nearly 18% in energy savings and $1.8 million in costs annually for the Mapleton foundry.