在伊利诺伊州北部的一口试验井中进行了离子交换、石灰软化和化学沉淀直接过滤的初步研究，以确定每种技术在从地下水中去除钡方面的有效性。文中给出了与每种处理技术相关的化学要求、每种技术的物理设施尺寸确定所用的设计标准、化学沉淀直接过滤的有效性和可靠性数据，以及在试验井实施每种处理系统的详细操作和维护成本。 所有的处理技术都能有效地去除钡，而离子交换系统是最经济的。包括7个参考文献、表格、图表。

Pilot studies of ion exchange, lime softening, and chemical precipitation-direct filtration were undertaken in a test well in northern Illinois to determine the effectiveness of each technique in removing barium from the groundwater. The chemical requirements associated with each treatment technique, design criteria to be used in sizing the physical facilities for each technique, data on the effectiveness and reliability of chemical precipitation-direct filtration, and detailed operation and maintenance costs for implementing each of the treatment systems at the test well are presented. All treatment techniques were effective in removing barium, while the ion exchange system was the most economic. Includes 7 references, tables, figures.