PhosphoReduc™ — Emerging Solutions For Phosphorus Removal And Reuse

By Aleksandra Drizo

Nutrients such as nitrogen and phosphorous can provide many benefits when they are properly used.  When they are applied as a fertilizer at agronomic rates they improve crop production. However, when they are used improperly or disposed of as waste they can negatively impact the environment. Water eutrophication caused by excess nutrients loading from human activities has been recognized as one of the major water quality impairments. The addition of just 1 g of phosphorus promotes growth of up to 100 g of blue green algae in recipient waters. Thus, excess phosphorous in waterwaysis recognized as the principal trigger of eutrophication and toxic blue-green algae blooms.

In March 2013, the USEPA reported that 40% of the nation’s streams and rivers have elevated phosphorus concentrations, while 55% of the waters cannot sustain the native aquatic life.The current cost of phosphorus pollution to the US economy is $4 billion/year when only lost recreation and depressed property values located near water fronts are accounted for. Currently, phosphorus(P) removal is generally only required only for municipal wastewater treatment facilities (WWTFs) and some stormwater applications (through best management practices, BMPs). Moreover, in the US for example,only 70% of the WWTFs are equipped to provide P removal, made either via conventional chemical or biological processes. These processes are complex, expensive,consume large amounts of energy, require intensive and costly operation and maintenance, and generate large volumes of sludge that must be appropriately disposed.In 2005, Jiang et al [1] developed comprehensive cost estimationsfor upgradingexisting WWTFswithenhance phosphorus removal. Two different configurations of phosphorus removal processes were compared: the Anoxic/Oxic (A/O) or Anaerobic/Anoxic/Oxic (A/A/O) processes, and the Activated Sludge (AS) process using chemical addition. The analyses were made for 4 different total phosphorus (TP) discharge limits (2 mg/L, 1 mg/L, 0.5 mg/L and 0.13 mg/L). The results showed that for all adaptation configurations, meeting the TP limit of 1 mg/l would require capital investments of hundreds of millions of dollars. In today’s global economic crisis many municipalities simply cannot afford the cost of retrofitting their WWTFs for P removal.

Apart from extremely high costs, the conventional chemical and/or biological methods used for P removal on WWTFs are not feasible for other phosphorus pollution sources such as, rural communities’households (septic systems) or agricultural activities such are animal, crop and other food production areas, and stormwater runoff.

Today, about 30% of population in developed countries relay on onsite wastewater treatment and disposal systems, e.g. septic systems, a methodwhich was developed over 100 years ago and typically consist of a septic tank and drain fields. Septic tank effluent, which can contain as much as 10-13 mg/L P is conveyed by gravity to a drain field where soils or other natural materials are assumed to provideP removal by assimilation and further effluent polishing.However, P retention capacity of soils is a finite process, and thus their ability to retain P significantly diminishes over time.Thus many of the drain fields installed over 15 years ago have long lost their P retention capacities. Despite growing scientific evidence that septic drain fields can represent a significant source of phosphorus loading to the watersheds (14 lbs P/single household/year), apart from Scandinavia, phosphorus removal regulations for onsite wastewater and disposal systems do not exist in the developed world.

Agriculture is the largest user of freshwater resources (85% of water globally) and consequently the largest polluter: phosphorus concentrations in livestock operations wastewaters and runoff range from 30 mg/L P (barnyards runoff, milk parlor, cheese processing effluents, heavy animal use areas) to as high as 200 mg/L P(feedbunks and silage runoff). Although surface and subsurface drainage runoff from crop production has low P concentrations (average below 1 mg/L P), P loading from croplands can represent significant P load to nearby streams, due to large volumes of water created by precipitation events. Yet, regulations that would require P removal from agricultural activities do not exist anywhere in the world.

Methods for phosphorus removal from wastewaters and stromwater runoff have emerged over the past few years. However, the current absence of the governmental regulations for phosphorus discharge limits (other than wastewater treatment plants, stormwater BMPs, and phosphorus detergent bans), coupled with the extremely high costs of environmental technologies verification (ETV) programs imposeinsurmountableobstacles in innovative phosphorus removal technologies applications. In the United States and Canada for example, the costs of federal applications for novel methods and technologies range from $120-140,000 per application, lasting 24-36 months. Individual State Permits do not require financial investments at the time of application, however, the review process can last from 12 to 18 months. Moreover, even when the initial approval is obtained, State regulators require investment of at least $20,000 for the innovative product installation and 12+ months obligatory water quality monitoring by a third party.

Over the past 6 years, PhosphoReduc (www.phosphoreduc.org) has developed ground breaking solutions to phosphorus polluted watersby combining readily available recyclable industrial raw materials and cutting edge design. Since their entrance in the market in 2008 with prototypes and product verificationsin the US and an exclusive license to two patent-pending technologies, PhosphoReducexpanded their wastewater and runoff treatment products from US across two additional continents, in ROC Taiwan (2010) and Brazil (2013).Moreover, PhosphoReduc^TMproducts are the only one on the market which provide both

• Phosphorus reduction from any point and/or diffuse pollution source and
• Phosphorus re-usefrom any point or nonpoint pollution source, through creation of value added phosphorus-rich products and soil amendments from PhosphoReduc^TM water filtration materials.

PhosphoReduc^TM phosphorus reducing products are energy efficient passive filtration systems consisting of one or more filter units filled with iron and/or calcium based PhosphoReduc^TM filtration media (PRFM). Phosphorus is removed via filtration, adsorption and chemical precipitation during passage of the polluted water through the system at specific hydraulic residence times.

They are customizable and scalable to provide over 90% phosphorus reduction of any pollution source, ranging from a single house onsite residential septic system (450 gal/day) to small scale wastewater treatment plants (e.g. up to 100,000 gal/day) and urban stormwater runoff.

In addition,PhosphoReduc^TMproducts offer the first solution to agricultural phosphorus pollution mitigation from livestock (barnyards, dairy and dairy by-products processing effluent, feedbank runoff treatment) and crop production (agricultural tile drainage, biofuels surface and subsurface runoff treatment).

PhosphoReduc^TM products can achieve phosphorus removal discharge requirements as low as 0.05 mg/L. In addition to phosphorus reduction, they provide 90% reduction in other water contaminants: pathogens, metals and minerals, organic matter and suspended solids.

As passive gravity-fed filtration systems, they are energy efficient, have simple installation with minimal land disturbance (e.g. reduced investment for landscaping), resulting in lower operational expenditure and capital expenditure compared to other phosphorus removal methods.

PhosphoReduc^TM Filtration media have significantly longer lifespans compared to other available on-site filter systems on the market. Additionally PhosphoReduc^TM products eliminate the need for phosphorus-removing salts addition thereby minimizing sludge accumulation for municipal and industrial wastewater treatment facilitieswhich leads to significant cost savings.

In addition to all of the above advantages in providing a solution to phosphorus pollution, PhosphoReduc^TM productsspent water filtration media enables phosphorus recycling through creation of phosphorus rich products for use as a soil amendment for acid mine reclamation, forestry, horticulture and landscaping (e.g. construction sites and new urban development landscaping).

Phosphorus recycling and re-use feature of PhosphoReduc^TM products is extremely important given increasing concern over world P reserves decline and its potential impacts on food prices and food security.

PhosphoReduc CEO, Dr. Aleksandra Drizo, is one of the three world pioneers who established the research field on phosphorus removal via industrial by-product materials in the 90s. She has been recognized worldwide as a thought leader in innovative phosphorus removal technologies.

For more information visit PhosphoReduc website (www.phosphoreduc.org) or contact Dr. Aleksandra Drizo, CEO at adrizo@phosphoreduc.com