Methods and processes for treating wastewater in a brewery in detail

Processing Brewery Wastewater

Processing brewery wastewater helps address the following issues in wastewater:

• The sugar and starch content, spent grains, alcohol yeast, and much higher organic compounds compared to domestic wastewater.
• High organic content leads to a large amount of sludge after the treatment process.
• Low pH: Natural acids are produced during production - hydrogen sulfide gas (H₂S) combined with water creates Sulfuric Acid (H₂SO₄).
• Average COD from 1300 - 5000 mg/l.
• BOD: a measure of the nutrient value of wastewater - averaging over 5000 mg/l. In other words, it requires a lot of oxygen to decompose.
• Total Suspended Solids (TSS) average 200 - 300 mg/l.
• High temperature: Brewery wastewater is always above 140°F, generated from hot water rinsing, hot caustic spray, water for cooling heat exchangers.

Methods for Brewery Wastewater Treatment

The brewery industry generates a large amount of wastewater discharged into the environment. According to research, during beer production, 8 - 14 liters of wastewater/liter of beer are produced, depending on the wastewater treatment technology at the brewery and the types of beer produced.

Furthermore, due to the high COD and BOD5 content of brewery wastewater, direct treatment using aerobic biological methods is difficult, often requiring pre-aerobic treatment followed by aerobic treatment. This method of brewery wastewater treatment is a technology that is widely applied in food processing wastewater treatment in general for good and stable efficiency.

Biological Method

The biological method uses microorganisms to break down organic pollutants in wastewater. Microorganisms use organic matter and some minerals as a source of nutrients to build cells. At the same time, they synthesize energy for living processes. Through the biological activity of microorganisms, pollutants are metabolized, and wastewater is cleaned.

The biological wastewater treatment process in the beer production industry can be divided into two processes: anaerobic digestion and aerobic digestion, which can be treated under natural or artificial conditions.

Wastewater before biological treatment needs to undergo mechanical, chemical, and physical treatment methods to remove coarse impurities, components that are detrimental to biological treatment.

Brewery Wastewater Treatment Process

The wastewater treatment system at a brewery is processed according to the following technological process:

Reception Tank

All wastewater through pipes is directed to a reception tank, where large waste materials are removed by screens. This is a preliminary treatment step to ensure smooth system operation.

Equalization Tank

Water is passed through an equalization tank. Continuous stirring devices balance the concentration of pollutants while regulating the flow of wastewater to the next stage.

Coagulation, Flocculation

Brewery wastewater has a very high organic content from barley grains, spent grains. These substances, with the help of coagulants, will agglomerate to facilitate the settling process.

Clarifier I

Here, large sludge flocs settle down and will move to the sludge storage tank.

UASB Reactor

Water from the clarifier passes through the UASB reactor to remove organic compounds and anaerobic gas-producing microorganisms in brewery wastewater. Here, hydrolysis, cleavage of high molecular compounds, acidification, and methanation occur.

Aerotank

Water passes through the aerobic tank, adding oxygen to the wastewater to help bacteria decompose organic compounds and convert energy into new cells. Oxygen is used to promote the growth of bacteria that can consume BOD, the higher the BOD, the more sludge needs to be removed from the wastewater.

Clarifier II

Here, sludge and wastewater are separated to be transferred to the disinfection tank.

Disinfection Tank

Helps remove disease-causing microorganisms with chlorine, wastewater is discharged into the receiving environment after meeting the QCVN 40:2011/BTNMT standard.

The biological treatment method is an environmentally friendly method with the lowest energy to clean brewery wastewater, reducing total suspended solids - TSS by up to 99%.

The wastewater treatment process in a brewery can be customized depending on BOD, COD, TSS, pH concentrations, and other basic indicators such as nitrogen (N), phosphorus (P), heavy metals, etc.

Toan A Provides Brewery Wastewater Treatment Systems

Toan A Environmental Technology Joint Stock Company specializes in providing brewery wastewater treatment services. We specialize in installing automated wastewater monitoring systems.

After a certain installation period, the equipment will automatically analyze and store in memory the parameters related to the quality of wastewater discharged into the environment, such as COD balance, SS, pH, chlorine, and capacity.

To learn more about our water treatment systems, please contact us. Toan A JSC will provide effective and environmentally friendly solutions for breweries nationwide.