2003 Progress Report: Diminishing Materials Use and Air Pollutants in Foundries via an Integrated Advanced Oxidation Process: Characterization of Materials and Pollutants at the Nano-ScaleEPA Grant Number: R829581
Title: Diminishing Materials Use and Air Pollutants in Foundries via an Integrated Advanced Oxidation Process: Characterization of Materials and Pollutants at the Nano-Scale
Investigators: Cannon, Fred S. , Komarneni, Sridhar , Voigt, Robert C.
Current Investigators: Cannon, Fred S. , Bhide, Harsh , Clobes, Jason , Firebaugh, Joel , Furness-Newburge, Jim , Goudzwaard, Jeff , Komarneni, Sridhar , Land, Josh , Milan-Segovia, Nohemi , Voigt, Robert C. , Wang, Yujue
Institution: Pennsylvania State University
EPA Project Officer: Richards, April
Project Period: January 1, 2002 through December 31, 2004
Project Period Covered by this Report: January 1, 2003 through December 31, 2004
Project Amount: $325,000
RFA: Technology for a Sustainable Environment (2001) RFA Text | Recipients Lists
Research Category: Sustainability , Pollution Prevention/Sustainable Development
The objectives of this research project are to: (1)employ a consortium of protocols to characterize and better understand the nano-scale effects that this advanced oxidation (AO) process has on green sand materials and air emissions; (2) experimentally identify and model AO effects as a function of distance from the molten metal interface; (3) apply this nano-scale data to enhance the extent to which the AO process effectively preserves and activates the coal within the green sand to adsorb and/or retain volatile organic compounds (VOCs) and thus prevent pollution before it happens; (4) apply this nano-scale data to enhance the extent to which the AO process preserves and activates clay that appears to be “dead” (i.e., unusable) in a manner that diminishes the wasting of spent clay; and (5) interface on the validation of these improvements at full-scale foundries via onsite trials informally coordinated by The Pennsylvania State University (PSU) team in collaboration with ongoing foundry operations.
Throughout the research period, tests have been conducted to characterize the effects of the AO system on emissions reduction and sand property improvements in green sand foundries. Testings conducted at the PSU laboratory indicated that AO treatment favorably changed green sand properties with respect to material conservation and emission reduction. The AO-treated green sand exhibited about twice as much pore volume and 50 to 100 percent higher m-xylene adsorption capacity as the non-AO-treated green sand. The AO-treated green sand also hosted 35 percent more cumulative surface charge than the non-AO-treated green sand. Moreover, the AO-treated green sand released less mass and VOC emissions than non-AO-treated green sand during the thermogravimetric analysis. These evaluations delivered key information to the present understanding of AO performance in full-scale foundries.
The mechanisms of AO processing on bentonite consumption reduction observed in a full-scale foundry were exploited. It was found that the ultrasonic component of the AO system could enhance the reclamation of active clay from the dust when the AO system was used in combination with the blackwater clarifier in a foundry. In addition, the ultrasonication caused a size reduction of the bentonite because of the delamination of bentonite particles. This size reduction improved the bonding efficiency of the bentonite. More important, it was found that the various advance oxidants in the AO water could degrade and mineralize the pyrolysis products of carbonaceous additives and core binders that were condensed on the bentonite surface after metal casting. This restored the damaged foundry properties of bentonite because of the pyrolysis products coating. As a combined result of these mechanisms, the bentonite consumption in the full-scale foundry could be reduced.
Experiments were conducted to evaluate the performance of the AO system (Sonoperoxone®) used in the green sand foundries. The research group monitored apparent OH*, hydrogen peroxide, and ozone concentrations in the liquid phase, along with gas phase ozone when operating an AO system. It was found that the combination of hydrogen peroxide, ozone, sonication, and underwater plasma enhanced the production of OH· radicals, and it was perceived that the OH· was the main AO species responsible for the emission reduction and clay reactivation.
Statistical tools were used to analyze critically more than 260 stack emission test results. It was found that considerable variation in VOC emissions could occur even when these stack tests were performed under identical production conditions. Furthermore, correlations between these stack test results and several lower cost surrogate sand system emissions tests were developed.
Full-scale foundries’ experience verified the effects of the AO system on material and emission reduction. When compared with non-AO-optimized conditions, the AO system diminished air emissions noticeably during mold cooling and shakeout. The emissions reductions for noncore castings have been 63 percent for VOCs (C4 to C16), 45 percent for benzene, and 36 percent for methane and ethane, and these reductions all were statistically significant to the 99 percent confidence interval. Concurrently, foundries have found they can use 20 to 35 percent less clay and coal and achieve the same casting quality.
We will study the effects of AO treatment on coal’s properties and pyrolysis behavior, test the possible mechanisms of VOC emission reduction from coal because of AO treatment, and study the possible factors that affect methylene blue test results.
Journal Articles on this Report : 2 Displayed | Download in RIS Format
|Other project views:||All 8 publications||8 publications in selected types||All 7 journal articles|
||Land JD, Cannon FS, Voigt RC, Goudzwaard J. Perspectives on foundry air emissions: a statistical analysis approach. Transactions of the American Foundry Society 2004;112(N 04-040):1075-1081.||
||Wang Y, Cannon FS, Neill D, Crawford K, Voigt RC, Furness JC, Glowacki CR. Effects of advanced oxidation treatment on green sand properties and emissions. Transactions of the American Foundry Society 2004;112(N 04-069):635-648.||