District cooling systems (DCS) utilize centralized plants to deliver chilled water via insulated pipelines, achieving 40-50% energy savings over conventional air conditioning through economies of scale and advanced chiller technology. However, water quality challenges—particularly with treated sewage effluent (TSE) and potable water—limit operational efficiency. TSE’s high total dissolved solids (TDS) with chemical treatment and organic content increase blowdown frequency and corrosion risks, while potable water use strains scarce resources across the globe with water being a precious commodity. Bio Organic Catalyst (BOC) addresses these issues through a patented formulation that enhances dissolved oxygen transfer, accelerates organic waste breakdown, and reduces chemical dependency, enabling sustainable water reuse and compliance with Local and International regulation.

Root Cause:

District cooling systems face inherent water quality challenges when utilizing alternative sources like treated sewage effluent (TSE) or managing potable water consumption. TSE, while cost-effective and aligned with circular water goals, introduces high total dissolved solids (TDS >1,200 ppm), organic contaminants (COD 5–40 ppm), and microbial risks (e.g., Legionella). These factors accelerate scaling, corrosion, and biofouling, forcing operators to increase blowdown frequency and chemical dosing—undermining water conservation efforts and energy efficiency. Meanwhile, reliance on potable water strains scarce resources in arid regions where policies mandate sustainable alternatives

1. TSE Water Limitations

• High TDS/Chlorides: Elevated total dissolved solids (e.g., chlorides >500 ppm) in treated sewage effluent (TSE) accelerate corrosion and scaling, reducing cycles of concentration and increasing blowdown frequency.
• Organic Contaminants: Starches, fibers, and microbial nutrients in TSE promote biofilm growth on heat exchangers, impairing thermal efficiency.
• Anaerobic Conditions: Low dissolved oxygen (DO <2 mg/L) in TSE systems fosters Legionella proliferation and hydrogen sulfide generation, leading to odor and infrastructure corrosion.

2. Potable Water Dependency

• Resource Strain: High freshwater consumption conflicts with water-scarce regions’ conservation mandates
• Operational Costs: Potable water treatment and blowdown management escalate expenses due to chemical dosing and energy use.

3. Chemical Treatment Shortfalls

• Toxic Inhibitors: Zinc, molybdate, and biocides introduce environmental hazards and corrode pipelines through by-product formation.
• Limited Efficacy: Traditional chemicals fail to address biofilms and organic waste under low-oxygen conditions, necessitating frequent cleaning.

4. Infrastructure Stress

• Scaling: Calcium carbonate and silica deposits on heat exchangers reduce heat transfer efficiency, increasing chiller energy loads by 10–20%.

Foaming: Microbiological contaminants and fine particulates (<5 microns) generate stable foam, causing pump airlocks and downtime.

Solutions:

Traditional chemical treatments, such as zinc-based inhibitors and biocides, offer limited efficacy against biofilms and introduce environmental hazards. This creates a critical gap between regulatory demands for non-potable water use and the operational realities of maintaining system integrity. Bio Organic Catalyst (BOC) bridges this gap by addressing TSE’s limitations and reducing potable water dependency through advanced oxygenation and enzymatic processes, enabling higher cycles of concentration without hazardous chemicals.

1. TSE Water Optimization

• Microbubble Oxygenation: BOC’s amphiphilic molecules generate ultra-fine Nano bubbles elevating DO to suppress Legionella and eliminate hydrogen sulfide.
• Enhances aerobic biodegradation of organic waste, reducing TDS-related blowdowns by 50–70%.
• Organic Waste Breakdown: Accelerates decomposition of starches and fibers via enzyme-driven catalysis, preventing biofilm formation on heat exchangers.
• Enables higher cycles of concentration in TSE systems, minimizing freshwater/ Make Up Water intake.

2. Chemical Elimination

• Non-Toxic Catalysts: Replaces zinc and molybdate with biodegradable catalysts, eliminating hazardous by-products and complying local and international regulatns and standards.
• Prevents scaling without acid treatments, protecting low-TDS RO permeate blends from corrosion.
• Pathogen Control: Aerobic conditions eradicate Legionella and E. coli in storage tanks, reducing cleaning frequency.

3. Energy Efficiency

• Aeration Energy Reduction: Cuts aeration energy by 40% through enhanced oxygen transfer rates, lowering operational costs.
• Heat Exchanger Optimization: Eliminates biofilm-induced thermal resistance, improving chiller efficiency and reducing electricity consumption by 15–20%.

Mechanistic Insights

• Biocatalytic Process: BOC’s fermentation-derived supernatant enhances oxygen transfer and enzymatic breakdown of organic waste, achieving rapid TSS reduction.
• Microbubble Technology: Ultra-fine bubbles increase gas-liquid interface area, accelerating chemical and biological reactions for scalable TSE treatment.

By integrating BOC’s solutions, district cooling systems overcome water quality constraints while achieving sustainability targets through chemical-free, energy-efficient operations.

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