The goal of the project was to eliminate the need to landfill-dispose of spent semiconductor-grade ion exchange resin used for deionized water production by finding viable recycling or reuse options for the material. The resin was generated between May and November of 1990.
Ion exchange resin from 2 anion and 3 mixed beds, although no longer useful for the purpose of producing semiconductor- grade deionized water, was analyzed and found to have a sufficient life expectancy remaining in it for use in other applications, such as boiler water, condensate, and wastewater treatment. By finding an interested party who could further utilize the resin's remaining exchange capacity in another application, the resin lost its status as a waste, and became a partially-used raw material instead. A Tennessee-based company specializing in portable water treatment systems was interested in using the resin in their facilities.
Spent ion exchange resin is listed on the company's NOR as a Class I nonhazardous waste, requiring manifested disposal in either a Class I secured landfill, or incineration. In addition, manifested disposal amounts must be reported on the company's annual waste summary. The total amount of spent resin was 434 ft3, or 26,350 lbs., in sixty-two 55-gal drums. Incineration by-products potentially produced would include carbon monoxide, styrene, and divinylbenzene. Although generally considered to be inert, it is possible that heavy metals retained by the resin over its life expectancy could cause a potential leachate problem in a landfill as it decomposed. Once the resin has been totally expended, it may be processed and reclaimed for its polymer value in the manufacture of other plastics or resins.
Details of Reductions
Additional Information :
The company avoided costs for disposal, manifesting and reporting requirements, and the portion of the annual Texas Hazardous Waste Generation fee that would have been due from the additional weight reported. In addition, the receiving company avoided potential costs for purchase of virgin resin.
1. SGS-Thomson disposal costs avoided: (for a 1-year period)
Landfill disposal $175/drum = $10,850 or
Incineration $275/drum = $17,050
Manifest/report burden 2 hrs = $ 37
Hazardous waste fee = $ 250
Total potential cost = $11,137 - $17,337
Resin analysis (5 exchange capacity profiles and RCRA waste profile analysis w/TCLP for one sample) = $1,820
Total cost avoided = $9,317 - $15,517
2. Tennessee-based mobil water treatment company virgin material costs avoided: (for a 1-3 year period)
Total cost for new ion exchange resin for 2 anion and 3 mixed beds:
2 an. beds, 95 ft3 ea., @ $175-190/ft3 $33,250-36,100
3 mxd. beds, 49 ft3 cation resin ea., @ $55-65/ft3 $ 8,085- 9,555
3 mxd. beds, 49 ft3 anion resin ea., @ $175-190/ft3 $25,725-27,930
Total potential cost $67,060-73,585
Subtract used resin acquisition costs:
Transportation from SGS-Thomson to Tennessee-based company $ 900
Commodity compensation to SGS-Thomson = $ 200
Total acquisition cost = $ 1,100
Total potential cost avoided = $65,960-72,485