Arvia Technology has developed a new approach to waste water treatment that promises to help API manufacturers remove complex contaminants cost-effectively. Technical director Nigel Brown explains
For nearly all industrial activity, water is a crucial resource and an increasingly significant overhead. Whether it is securing the supply of the required volume and quality of water, or the safe and secure disposal of waste and contaminated water, the increasing pressure on resource management and sustainability will only make "the right" water more expensive to acquire - and, crucially, to dispose of.
This is particularly true for the pharmaceutical sector, which not only requires access to the highest quality water, but also creates waste water that is often packed with complex contaminants, including Active Pharmaceutical Ingredients (APIs).
The most cost-effective approach to the treatment of these waste waters is using traditional biological processes; however, the APIs can pass through these with limited removals. Since these compounds must be removed prior to discharge, additional chemical or physical treatments must be employed, either in-house or by off-site specialist companies.
Activated carbon is the most widely used treatment process to achieve the removal of the non-biodegradable APIs. While technically efficient, it is only a concentration process, and once loaded the adsorbent material must be disposed of or regenerated.
Regeneration is often the most cost-effective and environmentally acceptable option. Industrially, regeneration is achieved using high temperature, high cost, thermal processes that give a 5-10% material loss and will often require transportation of loaded adsorbents to specialist off-site regenerators.
Other physical and chemical treatment methods require the use of hazardous and expensive chemicals, and/or produce secondary liquid or solid wastes that require further treatment and disposal, usually by landfill or incineration. Off-site transportation also presents a security risk, as third parties are then responsible for safeguarding precious compounds.
a new approach
Arvia has developed a technology that not only treats water without the need for added chemicals, but also creates no secondary waste other than innocuous gases (e.g. CO2) that can be directly released to the atmosphere.
This is achieved through adsorption and electrochemical regeneration. Pollutants are captured using Arvia's patented renewable adsorption material, Nyex, which is regenerated by a low-power electric current. Regeneration is achieved by electrochemical oxidation of the organic contaminants.
Nyex is a non-porous, highly conducting, adsorbent material that allows for rapid adsorption and electrochemical regeneration. This has allowed Arvia to create a process that completes the removal and regeneration in one self-contained unit with no internal moving parts as the operation is controlled through the injection of air. This innovation can be up to 50% more cost-effective than conventional techniques.
Sedimentation of the Nyex produces a bed of particles through which the current is passed, but the high conductivity of the adsorbent material means that only a low voltage (and hence low power requirement) is needed.
Tests on a range of combinations of APIs have so far proved successful, and there is significant interest from both the pharmaceutical and biotech industries. The obvious benefit is the cost. There is no longer the need for expensive chemical treatments and costly disposal or regeneration of secondary waste streams.
Nyex's simple regenerative qualities also result in improved efficiency as, unlike activated carbon, there is no need to shut the treatment process down in order to replace spent materials.
Zero solid waste means there is nothing to dispose of, which is increasingly significant, as April 2009 saw yet another hike in UK landfill taxes, now up to £40/tonne, and this will continue to rise by £8/tonne until 2013.
And because Arvia gives manufacturers the power to treat water in situ, it nullifies the security and cost implications of off-site treatment. This also raises the opportunity to reuse the treated water on site, reducing water bills or extraction costs.