Pharmaceuticals are one type of many emerging contaminants found in water supplies across the U.S. and around the world. This is due to the fact that wastewater discharged from the pharmaceutical industry cannot be properly treated in municipal wastewater treatment plant operations.
These compounds usually are manufactured in batch processes by active pharmaceutical ingredient manufacturers, bulk drug vendors and related companies. The processes introduce pharmaceutical drug residues into wastewater generated by pharmaceutical operations. In these various operations, large quantities of water are used for washing for product preparation and extraction, and for equipment washing.
A recent finding by the International Joint Commission, an association of representatives from the U.S. and Canada that reports on issues relating to the Great Lakes, indicates the presence of more than 42 pharmaceutical compounds with continuous frequency in the waters of the Great Lakes.
The impact of most of these emerging contaminants on the health of aquatic life and the public are not known. Therefore, it was concluded that better treatment methods and approaches are required to handle this issue.
Reducing Pharmaceutical Residue
There are several ways in which pharmaceuticals in water can be reduced. These methods include changes in policy and regulation, innovation in product formulation, and advanced pharmaceutical wastewater treatment that is decentralized and integrated into pharmaceutical production plants.
In terms of a policy and regulatory framework, the Safe Drinking Water Act (SDWA) is the policy that has done the most to address the issue of pharmaceutical pollution in the U.S.
The SDWA provides a Contaminant Candidate List to identify specific contaminants through a lengthy U.S. Environmental Protection Agency review process, but this does not guarantee required removal. There currently are no formal policies nor a regulatory framework specifically related to the reduction of pharmaceutical compounds in wastewater or in drinking water treatment in the U.S. and in many regions of the world.
Secondly, environmentally sustainable formulations and processes, innovations for product formulation, and treating health issues in different ways also can be components to solving the pharmaceutical pollution problem.
Lastly, the culmination of the process to reduce pharmaceuticals in the water supply is through the integration and implementation of onsite sustainable decentralized wastewater treatment. While there is no single technology to completely remove pharmaceuticals from wastewater, a combination of conventional and advanced treatment methods appear to be the best solution. These methods typically include the use of specialized electrocoagulation processes integrated with biological processes such as moving bed bioreactors or membrane bioreactors (MBR) followed by post treatment using an advanced oxidation process to reduce refractory and non-biodegradable residues.
Through the effective treatment of industrial wastewater effluent for discharge or potential reuse as well as stakeholder involvement, pharmaceutical compounds discharged into the water supply can be reduced while making a positive impact on the environment in the process.
Plan in Action
A pharmaceutical company wanted to reduce the discharge contaminants in its low-strength and high-strength wastewater streams to maintain compliance with existing regulations and meet sustainability goals.
The low-strength influent had 2,200 ppm of biological oxygen demand (BOD), 7,000 ppm chemical oxygen demand (COD), 1,200 ppm total suspended solids (TSS) and 2,700 ppm total dissolved solids (TDS).
The high-strength influent had 12,000 ppm BOD, 50,000 ppm COD, 2,600 ppm TSS and 50,000 ppm TDS with a pH between 6 and 6.5.
Genesis Water Technologies, with its local partner, designed and provided a solution to effectively handle the water streams. The high- and low-strength streams were separated into raw primary equalization tanks after an existing solvent-stripping process. The raw screened effluent was sent through a specialized electrocoagulation system followed by a dissolved air flotation process. The clarified water then was sent to an anaerobic hybrid reactor followed by biological treatment using an MBR system.
Tertiary treatment included advanced oxidation followed by distillation for the high-strength stream and reverse osmosis for the low-strength stream. Power for the treatment systems was subsidized from gas produced by the anaerobic reactor.
With these systems in place, the client met discharge requirements for TSS, BOD, COD and TDS reduction. The TSS was reduced to 1 ppm, COD to less than 100 ppm, BOD to less than 7 ppm and TDS to less than 500 ppm. The client also met its established sustainability goals.