SBIR Phase I: Neutralizing Utility Mercury Control Sorbents for Fly Ash Use in Concrete

这个小企业创新研究（SBIR）第一阶段项目将开发廉价的方法来预处理用于电厂汞控制的商用粉状活性炭（PAC），使它们不会干扰混凝土中粉煤灰的有效利用。本课题的目的是筛选和优化这些预处理方法。主要项目任务包括生产预处理样品；对原子吸收剂的影响、产生的胶结物和除汞性能的测试；并对所涉及的化学过程有了基本的了解。布朗大学的碳材料研究人员及其能源与环境技术实验室将协助这项工作。在商业上，粉煤灰废料在建筑应用中代替水泥是美国的一项技术。美国最大的回收成功案例。不幸的是，最近发现，即使为控制汞排放而向电厂烟道气体中注入极少量的PAC，也会使飞灰无法用于混凝土。高吸附性碳严重干扰了混凝土中添加的引气掺合料（AEAs）的引气和稳定作用。这对公用事业的经济影响可能是巨大的。因此，在此开发的PAC预处理方法将对AEA的不利影响降到最低，同时提高或至少不降解PAC的除汞性能，这是至关重要的。

This Small Business Innovation Research (SBIR) Phase I project will develop inexpensive methods to pretreat commercial powdered activated carbons (PAC) used for power plant mercury control so that they will not interfere with effective use of fly ash in concretes. The objective of this project is to screen and optimize such pretreatment methods. Major project tasks include producing pretreated samples; testing for effects on AEAs, resulting cements, and mercury removal performance; and developing a fundamental understanding of the chemical processes involved. Carbon materials researchers at Brown University and their Energy and Environmental Technologies Laboratory will assist in the effort. Commercially the substitution of fly ash wastes for cement in construction applications is one of America.s biggest recycling successes. Unfortunately, it was recently discovered that if even minimal PAC is injected into power plant flue gases for mercury emission control, the fly ash will be rendered unusable for concrete. The highly-adsorbent carbons severely interfere with the air-entraining admixtures (AEAs) added to concrete for air entrainment and stabilization. The economic implications for utilities may be huge. Thus the PAC pretreatments developed here which minimize adverse effects on AEA while enhancing, or at least not degrading, PAC mercury removal performance are of prime importance.