The water used in beer production consists of three aspects: brewing water, cooling water, and washing water. In China, the water consumption per ton of beer ranges from 15 to 40 tons, while in other countries, it is less than 8 tons.
According to evaluations, the high water usage in residential beer production may result from the following three factors:
Firstly, the manufacturing equipment is relatively outdated, and the cleaning tank, equipment, and pipes adopt basic cleaning methods, which have poor cleaning efficiency and require a large amount of water. Furthermore, the layout of equipment and pipes is unreasonable, necessitating a significant amount of flushing water or pipe water, which greatly increases water consumption.
Secondly, many factories use traditional production processes, which involve multiple steps. The equipment has small capacity, long delivery time or distance, numerous components to be cleaned during the process, and a large amount of cleaning water per unit of beer output.
Lastly, inadequate focus on water conservation or recycling is a common issue in some small breweries.
In order to reduce water consumption in beer production equipment, the following two aspects can be considered:
1. Recycling
Recovery measures are primarily applied to cooling water and washing water, which account for approximately 80% of the total water consumption for every ton of beer produced. This portion of water is necessary in the production process, as each stage requires specific water.
Almost every stage requires cleaning or cooling. The reusable portion of water is quite substantial and includes:
Brewing water can be used as the initial cooling water for the plate heat exchanger, and the outlet of the cooling water is connected to the hot water tank. This water can be used as saccharification water.
In the refrigeration system, a large-capacity pool is built to collect cooling water for recycling. The cooling water from the ammonia compressor and air compressor can also be collected and circulated in the same manner, significantly reducing cooling water consumption.
All water used for cleaning tanks is collected in the tank cleaning device. The biochemical oxygen demand (BOD) and chemical oxygen demand (COD) of this water are extremely low, with a weakly alkaline pH value (pH7~7.8). It can be used for soaking wheat, as well as for cleaning floors, open channels, and sewage systems.
The cleaning water and hop cleaning water are fully recovered and used as feed water for the subsequent saccharification process.
By utilizing CIP (clean-in-place) cleaning equipment, the final rinse water can be reused as the initial rinse water for the next cleaning cycle.
Recover the condensed water from the steam heating device. It can be mixed with brewing water as saccharification water or cleaning water to reduce water consumption.
2. Conservation
Reducing the amount of flushing water can be achieved by using higher water pressure and shorter flushing time. When scrubbing tanks and pipes, please minimize the water flow to avoid on-site water waste.
Strict control over the overall use of saccharification water is necessary. Properly arrange the number of washes and the amount of water used for each wash, and try to avoid excessive cleaning water entering the boiling pot (due to boiling time restrictions) or being drained without recycling. The water-to-mash ratio should be appropriate, and the mash should not be too thin to prevent increased pot evaporation.
It is important to control the water running time for each transport pipe and beer filter to achieve the goal of water conservation.
When discharging residues such as coagulated sediment, yeast, and other wastes, special equipment should be used. Avoid using cleaning methods to discharge residues and do not allow the use of underwater wheat bins. After sludge discharge is completed, rinsing can be done with less water first, followed by another rinse to save rinse water.
