Nominated by O'Brien & Gere
Typically, conventional Reverse Osmosis (RO) membrane based technology can effectively remove unwanted contaminants at 70-80 % recovery rate. However, the remaining brine reject stream generated (20-30%) by the conventional RO process will require disposal with associated fees. Reducing the reject volume will not only benefit in reduced discharge costs but can provide other possible disposal alternatives that can further eliminate direct discharge and it's impact on the environment. O'Brien & Gere Engineers, located in Bluebell, Pa, understood the vital need for water conservation, recycle, and the strong need to address water shortages, maximize fresh water utilization and minimize the volume of waste streams to enable their economical disposal in both the industrial and municipal markets.
O'Brien & Gere took it upon themselves to further develop the patented ARROW process to include the funding of an ARROW pilot system. The pilot system is the first step in evaluating the treatability of the water source in question. With the information/data provided by the pilot system, a full-scale system can be designed to accommodate the facilities hydraulic requirements and infrastructure modifications.In a recent case, a Mercer County, New Jersey based pharmaceutical client approached O'Brien & Gere to provide a solution in reducing and reusing their existing wastewater effluent discharge. The ARROW treated wastewater would be reused for cooling tower make-up water and other miscellaneous industrial water needs.
Sustainability Narrative
In the summer of 2007, the ARROW pilot system was employed at the pharmaceutical site to determine the treatability and maximum recovery rate that could be achieved. After three months of pilot testing, the ARROW system achieved 97% recovery rate. Based on the 97% recovery rate achieved, only 3% is considered as a waste stream requiring discharge. By reusing the ARROW purified water for Cooling water needs, the facility was able to reduce well water needs and associated costs. In addition, to well water savings the purified water quality would allow the facility to operate it's cooling towers at a higher cycles of concentration thereby reducing cooling tower blowdown and overall chemical costs. The remaining 3% waste stream would be hauled of site for final disposal. By disposing of the discharge off site, the facility no longer requires direct discharge to a local stream. Upon completion of this successful pilot, O'Brien and Gere will design the full-scale system to be put into operation by early 2009.
Results
The ARROW technology is a new and patented approach in configuring conventional water treatment equipment to meet water conservation, reduction and reuse needs in all markets. The process provides a novel, cost-effective approach for maximizing the recovery of purified water/wastewater. The benefits of this state-of-the-art technology are summarized below:
- Address increasing stringent discharge limitations placed on municipal and industrial sectors
- Comply with water reuse mandates
- Pro-active solutions to deteriorating water supply & quality
- The process integrates simple, proven membrane and conventional water treatment steps including efficient pre-treatment and pre-filtration, reverse osmosis, ion-exchange and/or chemical precipitation into a unique, highly efficient system. (See Figure 1)
- Minimum overall process cost per unit product water volume, which renders the water affordable. The savings realized in terms of raw water cost and wastewater disposal costs render the process economically viable.
- The ARROW process has a minimum adverse impact on the environment since in many cases the small volume of rejects produced by ARROW can be evaporated naturally in an evaporation pond or by using a mechanical means to achieve Zero liquid discharge.
As word gets out about this unique membrane based system, the industrial and the municipal sector, both globally and locally, will see the advantages of reducing and recycling water/waster not only for their own needs but the positive aspects it will have the environment.
