Municipal Solutions
Municipal wastewater treatment poses two key challenges: nitrogen pollution and waste sludge disposal. CASTion can help you address these challenges efficiently, cost-effectively and responsibly. We can help you convert ammonia from filtrate and centrate streams into a commonly used fertilizer and increase the energy content of waste sludge so it can be recovered as fuel. The bottom line? A more cost-efficient, responsible treatment method than traditional enhanced nitrogen removal and sludge landfilling.
Why Are Our Municipal Solutions Better?
Maximum Recovery and Sustainability
At CASTion, we don't just treat wastewater--we recover the value in it for you. Our Ammonia Recovery Process (ARP) can recover 80% or more of the ammonia in centrate and filtrate streams and reuse or recycle the ammonia as ammonium sulfate fertilizer. Our ThermoFuel Process reduces water in sludge to increase its energy content, which can then be recovered as a fuel.
Superior Technology with a Smaller Footprint
Now you can get advanced technology that helps save money and the environment. CASTion's solutions are far more efficient and cost-effective than traditional technologies. Our Ammonia Recovery System offers lower capital and operating costs as well as a much smaller footprint. As a retrofit to an existing wastewater plant, it can reduce or eliminate the need for enhanced nitrogen removal.
Significantly Lower Operating and Capital Costs
How do we help you save? Our systems are easy to operate and maintain. Because they are manufactured, you avoid the capital costs associated with the design and construction of in-place systems. And because we recover ammonia rather than just treating it, your costs are significantly lower.
Minimal Emissions
Our CAST and RCAST technologies are enclosed systems. That means they produce minimal air emissions. And because we recover rather than just treat, our systems offer much lower greenhouse gas emissions.
Ammonia Recovery Process (ARP)
So how does it work? To begin the ARP, the wastewater is conditioned so that neither suspended solids nor precipitates can reach the ammonia removal operations. If the ammonia concentration is high, vacuum stripping--using our patented RCAST system--is used to capture the ammonia that would readily volatilize (about 80%).
Influent (with 300 ppm ammonia-nitrogen or less) is then input to an industrial grade ion exchange resin that selectively adsorbs the ammonia. The adsorption columns are regenerated using either brine or sulfuric acid. The regeneration solution is used repeatedly, where the ammonia concentration builds up to several thousand ppm. The spent ammonia-laden regeneration solution is stripped of ammonia to produce a commercial-grade (about 40%) solution of ammonium sulfate. This figure illustrates the process:
ThermoFuel Renewable Energy Process
The ThermoFuel Process is an innovative renewable energy process that provides a permanent solution for biosolids disposal. This patented technology (US patent 6,893,566) was designed as a low-cost, environmentally effective method of upgrading existing wastewater treatment plants to EQ Class A biosolids production without the use of storage ponds or lagoons. ThermoFuel lowers the operating cost of the overall wastewater plant while improving treated water quality.
ThermoFuel produces a sterile, stable product that exceeds the requirements of Class A Exceptional Quality Biosolids and meets the pathogen and vector attraction reduction requirements of 40 CFR Part 503 Regulations. Plant operators can use the ThermoFuel high-energy product on-site to generate heat and power or export it for use as a fuel substitute or blending agent for power plants, municipal solid waste incinerators, cement kilns, and similar applications.
The ThermoFuel Process represents a significant advancement of the sludge-to-oil reactor system (STORS) process licensed from Battelle Memorial Institute. ThermoFuel is designed to react the thickened waste activated sludge (WAS) at elevated temperature (530°F) and pressure (1,200 psi) to convert the sludge into a high-energy solid fuel, with an average range between 9,000 – 10,000 Btu per pound. In addition, it will remove the nitrogen (ammonia) and convert it to an ammonium sulfate solution and produce a low-nitrogen stream of soluble organics and fatty acids. This stream will be returned to the plant for use as a carbon source for biological nitrogen removal (BNR) and biological phosphorous removal (BPR).
The heat used in the ThermoFuel Process is recovered and can be used to pre-heat primary sludge to the temperature needed for thermophilic anaerobic digestion. Due to the thermal recovery using temperature differentials to drive heat transfer, and the extended thickening of the WAS, the ThermoFuel Process requires less energy to achieve thermophilic digestion than conventional heating of the combined WAS and primary sludge.
Find our how our Municipal Solutions can help you meet your wastewater challenges; visit our Case Studies and Technologies pages.
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