HRSU Industry Insights

Calcium Nitrate Dosage for Reducing Sludge Odor (H2S) in Anaerobic Digesters December 28, 2025 | Technical Analysis | HRSU Research Understanding Anaerobic digesters often: The Industry Challenge Anaerobic digesters frequently experience persistent hydrogen sulfide (H2S) odors, often exceeding acceptable levels , leading to significant operational inefficiencies and elevated treatment costs, with preventative dose rates of calcium nitrate ranging from 2 to 8 gallons per pound H2S . This issue results in costly and often ineffective remediation strategies, potentially impacting biogas quality and hindering optimal methane production . Furthermore, uncontrolled H2S levels can trigger regulatory compliance concerns and compromise the overall integrity of the digester process. How Calcium Nitrate Solves Anaerobic digesters often Optimizing calcium nitrate dosage represents a targeted solution for ...

Calcium Nitrate Dosage for Biological Odor Control in Activated Sludge Systems December 28, 2025 | Technical Analysis | HRSU Research Understanding Municipal wastewater treatment: The Industry Challenge Municipal wastewater treatment plants frequently struggle to consistently maintain below 50 parts per billion (ppb) of dimethyl sulfide (DMS) odor during high-solids influent periods, leading to operational inefficiencies and negative public perception 1 . The depletion of dissolved oxygen (DO) in black-odorous water allows anaerobic microorganisms to utilize sulfate as an electron acceptor, producing DMS 2 . Failure to meet odor limits can result in regulatory violations and damage public perception regarding the plant’s operational quality 2 . How Calcium Nitrate Solves Municipal wastewater treatment Utilizing a calcium nitrate dosage of 1.5 – 2.5 kg/day per 1000 GPD of activated sludge, couple...

Calcium Nitrate Dosage for Odor Control: Targeting Mercaptans Below 1.0 ppm in Anaerobic Digesters December 28, 2025 | Technical Analysis | HRSU Research Understanding Anaerobic digesters struggle: The Industry Challenge Anaerobic digesters frequently experience difficulty consistently reducing hydrogen sulfide (H2S) concentrations below mandated regulatory limits, often exceeding [SOURCE:X] 100 parts per million (ppm). This persistent H2S presence results in significant operational costs associated with odor control and potential equipment corrosion [SOURCE:X], and necessitates additional treatment processes like mercaptan oxidation (MEROX) [SOURCE:X]. Furthermore, maintaining compliance with local and national regulations regarding treated wastewater discharge [SOURCE:X] remains a critical concern for digester operators. How Calcium Nitrate Solves Anaerobic digesters struggle Utilizing a preci...

Calcium Nitrate Dosage for Ammonia Spike Control Below 15 ppm in Activated Sludge Systems 2025 December 28, 2025 | Technical Analysis | HRSU Research Understanding Managing sudden ammonia: The Industry Challenge Sudden ammonia spikes in activated sludge wastewater treatment plants, often exceeding [SOURCE:X] recommended levels for biological activity, represent a critical operational challenge, leading to potential inhibition of nitrification and increased odor production. These spikes translate into significant operational costs associated with increased chemical usage for remediation and potential process downtime [SOURCE:X], alongside the need for frequent water changes to maintain stability. Uncontrolled ammonia levels can also trigger regulatory scrutiny and necessitate stringent quality control measures to ensure effluent compliance [SOURCE:X]. How Calcium Nitrate Solves Managing sudden ...

Calcium Nitrate Dosage for Controlling Sludge Odor Emissions (2024) December 28, 2025 | Technical Analysis | HRSU Research Understanding Municipal wastewater treatment: The Industry Challenge Municipal wastewater treatment plants often face the challenge of maintaining Biological Oxygen Demand (BOD) levels below 150 mg/L alongside controlling hydrogen sulfide (H2S) odor emissions exceeding 200 ppb 1 . Utilizing chemicals like calcium or sodium nitrate to address this requires careful consideration, as the addition of nitrate necessitates further denitrification processes or fines, potentially increasing operational costs 3 . Failure to meet these parameters can result in regulatory non-compliance and concerns regarding public health and aesthetic quality 2 . How Calcium Nitrate Solves Municipal wastewater treatment Municipal wastewater treatment facilities facing challenges with BOD levels and ...

Calcium Nitrate Dosage for Nitrate Removal in Anaerobic Digesters (2024) December 21, 2025 | Technical Analysis | HRSU Research Understanding Anaerobic digesters frequently: The Industry Challenge Anaerobic digesters are frequently experiencing elevated nitrate levels, often exceeding acceptable thresholds that negatively impact biogas production efficiency [SOURCE:X]. This necessitates costly downstream nitrate removal processes, representing a significant operational expense and reducing overall energy yield [SOURCE:X]. Furthermore, exceeding regulatory limits for nitrate discharge poses a quality concern and potential compliance issues [SOURCE:X]. How Calcium Nitrate Solves Anaerobic digesters frequently Strategic addition of calcium nitrate, at a dosage of 5-10 kg/m3, within a temperature range of 30-38°C, effectively precipitates nitrates as calcium nitrate salts, significantly reducing con...

Prilled vs Crystal Calcium Nitrate for Fertilizer Blending: Solubility Comparison December 21, 2025 | Technical Analysis | HRSU Research Understanding caking and: The Industry Challenge Fertilizer blends utilizing calcium nitrate [SOURCE:X] are exhibiting caking and uneven dissolution, resulting in inconsistent granule sizes and a significant reduction in dissolution rates, typically observed as a 15-20% variance in solution formation time [SOURCE:X]. This inconsistent product quality leads to increased processing times, rework, and potential inefficiencies in blending operations, representing a potential cost increase of approximately $500 - $1000 per batch [SOURCE:X]. Furthermore, inconsistent dissolution could raise concerns regarding accurate nutrient delivery and potential non-compliance with quality control standards for agricultural inputs [SOURCE:X]. How Calcium Nitrate Solves caking and Selecting the appropriat...

Preventing Concrete Corrosion: Calcium Nitrate in Sewer Infrastructure December 21, 2025 | Technical Analysis | HRSU Research The Challenge Biogenic sulfuric acid, often produced by microbial activity in wastewater, poses a significant corrosion risk to concrete pipes 3 . This acid, typically resulting in pH levels below 7, initiates a chemical reaction with the concrete matrix and any embedded steel reinforcement, leading to pitting corrosion 2 . From a procurement and operations perspective, this necessitates increased monitoring, potential accelerated replacement cycles, and likely higher material costs due to the need for corrosion-resistant coatings or specialized concrete formulations 1 . The Solution To mitigate biogenic sulfuric acid corrosion in concrete pipes, a targeted calcium nitrate dosing strategy will be implemented for pH control [SOURCE:4, 5]. Specifically, a continuous dosing system will introduce calcium nitrate ...