Abstract

Arsenic is one of the eight metals regulated under RCRA (Resource Conservation and Recovery Act). Arsenic can cause many health problems, including skin cancer, lung cancer, and bladder cancer. It is also known to be a cause of diabetes, pulmonary and cardiovascular diseases. The US EPA stipulates the limit for arsenic levels in the drinking water to 0.01mg/l or 10 parts per billion (ppb).

The main goals of this research involved the following 3 main objectives:

A. The first goal involved the engineering design evaluation of the water filter media.

B. The second goal encompassed analyzing the role of lingocellulosic fiber in the capability increase of particle adsorption and abstraction in an optimized water treatment media, purposed for arsenic removal.

C. The third objective comprised of studying the ultimate environment-benign disposal of the arsenic-laden foul media.

In view of the intended eventual disposal method for this media, other sought-after properties of its components included: ability to foment biochemical reactions, porosity, and biodegradability. The projected method for arsenic abatement and eventual disposal was through phytoremediation. The media contained lignocellulosic fiber (dehydrated Zea mays or corn husk) and coconut shell PAC (Powdered Activated Carbon), as part of its makeup. The efficacy of this arsenic-removing media was measured. Different disposal alternatives for arsenic-laden media were defined. The filter media components were measured and assembled by using the following ratios of PAC and corn husk: 75:25 and 50:50 ratios. A constant mass of an anthracite layer was used. Initially, a constant mass of Fe₂O₃ was placed on the top layer of the filter media. The estimated grade of our newly designed water filter, deduced after juxtaposing its features to the regulatory design criteria, was, approximately, equal to 75%. As expected, the total mass of the spent media decreased with the lower ratio of lingocellulosic fiber. Both ratios of PAC and corn husk removed arsenic in comparable manner, but at different rates. The lowest turbidity was observed when the Fe₂O₃ was removed from the media.