Application of Sodium Acetate Series Carbon Source Products in Sewage Treatment Station in Low Temperature Region

Wastewater treatment facilities in cold regions commonly encounter prominent operational bottlenecks in winter. Low water temperatures drastically inhibit microbial activity, while traditional carbon sources are prone to crystallization and poor solubility. These issues lead to insufficient denitrification capacity, unstable system operation, and persistent difficulty in keeping effluent total nitrogen within regulatory limits. The following four series of sodium acetate products are uniquely formulated to adapt to low-temperature working conditions, effectively solving winter nitrogen removal challenges for wastewater plants.

1. Industrial-Grade Liquid Sodium Acetate (20% / 25%)

Core Function

Serving as the mainstream dedicated carbon source for winter denitrification in cold regions, this liquid product delivers fast-acting organic nutrients to denitrifying bacteria under low-temperature environments. It effectively sustains microbial metabolic activity, guarantees stable and efficient nitrogen removal throughout winter, and maintains balanced pH values in biochemical tanks to ensure consistent system operation.

Product Advantages

The product features excellent low-temperature stability without delamination or freezing. As a ready-to-use liquid, it eliminates on-site dissolving operations and avoids freezing-related construction risks. It triggers denitrification far faster than traditional methanol and starch carbon sources, with no refractory by-products generated in the treatment process. Non-flammable and non-explosive, it greatly improves safety in plant storage, transportation and field application.

Application Method

Dosage is determined based on a carbon-nitrogen ratio of no less than 4.5:1, with a conventional dosing concentration of 35–60 mg/L for direct addition to denitrification tanks. Under extreme low-temperature weather, the dosage can be appropriately increased by 10%–15% to compensate for reduced microbial activity. Meanwhile, storage tanks and supporting pipelines need continuous thermal insulation.

Precautions

When the ambient temperature drops below -10℃, the solution may crystallize. Supporting heating and insulation measures for pipelines and storage facilities are required. Excessive dosing will lead to unnecessary rise in effluent COD and increase winter operating costs.

2. Industrial-Grade Solid Sodium Acetate (58%–60%)

Core Function

Ideal for carbon supplementation in small and medium-sized wastewater plants in cold areas, this conventional solid carbon source supports stable denitrification and provides continuous pH buffering. It stabilizes the biochemical system operation under low-temperature conditions and adapts well to the intermittent operating mode of seasonal wastewater treatment facilities.

Product Advantages

The material maintains stable physical properties during low-temperature storage, with low caking tendency and good powder fluidity. It dissolves faster at low temperatures than ordinary solid carbon sources, delivering reliable nitrogen removal performance. It features controllable comprehensive costs and convenient procurement, storage and transportation, making it suitable for routine winter carbon supplementation.

Application Method

Prepare a 20%–30% aqueous solution with warm water at 15–25℃ before pumping into the denitrification system. The specific dosage is accurately calculated according to the actual total nitrogen load of inlet water. It is recommended to use the prepared solution immediately to prevent secondary crystallization under low temperature.

Precautions

Incomplete dissolution in low-temperature environments may cause pipeline blockage. The product is highly hygroscopic; sealed and dry storage is mandatory after opening to avoid moisture absorption, caking and reduced efficacy.

3. Industrial-Grade Anhydrous Sodium Acetate (98%–99%)

Core Function

As a high-purity, fast-acting emergency carbon source, it targets the common winter problems of insufficient microbial activity and severe carbon source deficiency. It rapidly boosts denitrification efficiency and effectively copes with sudden water quality and water volume impact loads in cold seasons, ensuring stable effluent standards.

Product Advantages

Boasting high effective carbon content, it delivers significantly better low-temperature bioavailability than trihydrate sodium acetate. With ultra-low impurity content, the prepared solution has a lower freezing point and stronger low-temperature stability. It resists moisture absorption and caking during long-term storage, fully meeting emergency carbon supplementation demands in extreme cold weather.

Application Method

Prepare a 10%–15% aqueous solution with warm water for emergency use in winter. For daily operation, it can be compounded with liquid sodium acetate to balance treatment effect and operating costs. Strict water temperature control is required during dissolution to ensure full solvation.

Precautions

Heat release during dissolution easily causes tank condensation under low-temperature environments. High-concentration solutions may crystallize under extreme cold conditions, so finished solution storage requires complete thermal insulation measures.

4. Low-Temperature Special Composite Carbon Source

Core Function

Developed exclusively for cold-region wastewater treatment, this long-acting composite carbon source solves the core pain points of weak microbial activity and low denitrification efficiency in ultra-low temperature environments. It fully activates sludge microbial metabolism, improves winter nitrogen removal capacity, and effectively controls excess sludge output to reduce overall treatment costs.

Product Advantages

It features an ultra-low freezing point, maintaining stable fluidity without crystallization or stratification even at -20℃ without auxiliary heating. Compared with single sodium acetate products, its low-temperature bioavailability is greatly improved, raising the comprehensive denitrification rate by more than 30%. It effectively cuts down sludge treatment and disposal costs during winter operation.

Application Method

The original concentrated solution requires no dilution and can be directly dosed into denitrification tanks. The conventional dosage ranges from 30 mg/L to 50 mg/L, which can be dynamically adjusted according to real-time water temperature and water quality changes, perfectly matching automatic dosing systems.

Precautions

Different composite formulas vary greatly in low-temperature adaptability; small-scale pilot tests are suggested before large-scale application. Long-term storage must be sealed to prevent external microbial contamination and product deterioration.

Industry Application Case

A municipal wastewater treatment plant in a typical cold region has a daily treatment capacity of 5,000 cubic meters. In winter, the in-pipe water temperature consistently stays below 6℃, with the extreme low temperature reaching -22℃. The raw water carbon-nitrogen ratio is only 3.2:1, far insufficient to support stable denitrification. The plant previously adopted methanol as the carbon source, which frequently froze and failed to exert efficacy, resulting in long-term excessive total nitrogen in effluent.

After replacing with the dedicated low-temperature composite carbon source at a stable dosing concentration of 40 mg/L, the plant completely eliminated pipeline crystallization and blockage problems. The overall denitrification efficiency increased by 42%, and effluent total nitrogen was steadily controlled below 10 mg/L. Compared with the original methanol dosing scheme, the plant reduced winter operating costs by 18%, thoroughly solving the difficult problem of unstable nitrogen removal in ultra-low temperature environments.