Table 1. Reduced Emissions Using a Seacoal-Free Green Sand Mixture Process Sources of CO
Cast Iron Other Process Sources (clays, etc.) Total of Iron and Other Sources Phenolic Urethane Cores in Green Sand (no seacoal) Phenolic Urethane Cores in Green Sand (with seacoal) Green Sand Molds with Seacoal (no cores) Green Sand Molds with Graphite Parting (no cores or seacoal)
of the metalcasting facility workers to hazardous emissions. Individuals were fitted with personal sampling pumps to determine their actual exposures. To Pride’s surprise, OSHA measured for coal tar pitch
volatiles emissions. Unaware of the maximum allowable level of this byproduct of heating coal tar, the metalcasting facility thought its results would be acceptable. Its test values were above the allowable level. In response to the failed test, Pride began the process of con-
verting to a sand mixture containing no carbon. Te new mix- ture has had little effect on the company’s green sand properties. Pride isn’t the only metalcasting facility that has experi- mented with green sand mixtures using reduced or no seacoal, a carbonaceous material commonly used to improve mold properties. A number of facilities in Europe, including a large iron foundry in the Netherlands, also have taken up the strategy. Te topic of carbon monoxide (CO) emissions in green sand facilities also has drawn the attention of industry trade groups and been discussed by numerous researchers at conferences and seminars over the past five years. With this attention, industry analysts expect a growing trend toward reduced seacoal.
CO (lbs./ton of metal) 0.97 0.43 1.4 1.82-2.05 4.23-4.73 5.53-5.6 1.35-2.75
排放量来衡量危害程度。在不知道加热煤沥青这个副产 品的最大允许水平的情况下，原以为铸造厂的排放量是 可以接受的，但实际检测结果却显示高于允许值。 为解决这次测试中的问题，Pride 公司开始转成使用 无碳混合砂工艺。新混合砂对该公司的湿型砂性能几乎 没有影响。
虽然碳质材料通常可用来改善铸型性能，但Pride 公 司并不是唯一进行降低煤粉使用或采用无煤粉混合砂 铸造设备试验的工厂。欧洲一些铸造厂，包括荷兰的一 个大的铸铁厂，也已经采取了这一战略。湿型砂设备中 CO排放议题已经提交给行业贸易团体，并在过去五年 中被许多研究人员在研讨会上讨论过。鉴于这种关注程 度，业内分析师预计，降低煤粉使用是大势所趋。
了解你的排放量
由加利福尼亚州麦克莱伦LLC技术大学执行的铸造排 放量降低项目测试发现，在浇注、冷却和落砂过程中一
Fig. 1. A Netherlands- based ferrous facility achieved significantly reduced emissions using a seacoal-free green sand mixture.
图1 荷兰铸铁厂使 用无煤粉湿型砂混 合物取得了降低排 放的显著效果
May 2013
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