Wastewater Treatment Case of a Pharmaceutical Company in Korea

Project Name: Wastewater Treatment Case of a Pharmaceutical Company in Korea

Pollution Type: Pharmaceutical and Chemical Wastewater

Treatment Scale: Daily treatment capacity of 5,000 tons

Treatment Technology and Process: Physicochemical + Biological

Product Used: polyaluminum chloride, polyacrylamide

Characteristics and Challenges of Pharmaceutical and Chemical Wastewater Treatment:

(1) Due to the complex composition of biopharmaceutical wastewater, it contains residual solvents and a large amount of refractory organics, resulting in severe organic pollution. At the same time, the wastewater discharge volume is relatively small, with high concentrations of residual reactants, products, solvents, catalysts, etc., with COD concentrations reaching hundreds of thousands of milligrams per liter.

(2) Biopharmaceutical wastewater is incompatible with biological treatment systems due to high concentrations of COD, TSS, salts, and significant pH fluctuations. Inorganic salts are often by-products of synthetic reactions and remain in the mother liquor.

(3) Large pH variations lead to the discharge of acidic or alkaline water, with significant consumption of acids and bases for neutralization reactions.

(4) The composition of the wastewater is uniform, lacking sufficient nutrient sources, making it difficult to cultivate microorganisms.

(5) Some raw materials or products have biological toxicity, with compounds that are too concentrated or too toxic per unit volume of biomass. They may be refractory to biodegradation, such as phenolic compounds, anilines, heavy metals, benzene series compounds, halogenated hydrocarbon solvents, etc.

Polyaluminium Chloride (PAC) Solution and Technical Characteristics:

The high and low-concentration wastewaters are first pretreated separately. Before biological treatment, necessary preliminary physicochemical or chemical pretreatment is carried out on the biopharmaceutical wastewater. The pretreated wastewaters are then mixed for biochemical and physicochemical treatment. After effectively reducing the concentrations of high-concentration inorganic phosphorus and heavy metal zinc ions (Zn2+) in the wastewater, subsequent biological treatment is utilized to improve its efficiency. Wastewater containing ammonia nitrogen and phosphate ions is mixed and polyaluminum chloride is added for chemical precipitation to remove ammonia nitrogen and phosphorus. After the organic concentration is reduced to a certain level, it is mixed with low-concentration wastewater for treatment. The water quality and quantity characteristics of the pharmaceutical wastewater are thoroughly studied and analyzed to select the appropriate scheme and design the detailed process, minimizing the investment in the wastewater treatment project and the daily operating costs of the system.

Treatment Results:

(1) The recommended wastewater treatment process route yields good treatment results for petrochemical oily wastewater.

(2) With reasonable biochemical design parameters, only one stage of biochemical treatment is required for the entire water plant to meet the inlet requirements of the reuse water device, shortening the reuse process.

(3) The recommended reuse water treatment process route ensures that the product water meets the reuse water standards of the Sinopec Group, ensuring the normal operation of the circulating water plant at high concentration multiples.

(4) The pretreatment process using multi-media filtration, UF, and activated carbon can not only ensure the long-term operation of RO but also ensure that the discharged concentrated water meets discharge standards.