Environment: Sewage treatment plants are running out of water purification chemicals

Certain chemicals for cleaning wastewater are becoming scarce in sewage treatment plants nationwide - which could become a problem for rivers.

Environment: Sewage treatment plants are running out of water purification chemicals

Certain chemicals for cleaning wastewater are becoming scarce in sewage treatment plants nationwide - which could become a problem for rivers. So-called precipitating agents, i.e. iron or aluminum salts, normally bind phosphates dissolved in the wastewater during chemical water purification and thus prevent them from entering rivers in high concentrations.

According to the news magazine Der Spiegel, more and more sewage treatment plants are struggling with delivery problems for precipitants. Without any precipitants, municipal sewage treatment plants are forced to discharge wastewater with a high phosphate content into the rivers.

This is a nationwide challenge, said the Lower Saxony Ministry of the Environment on Friday when asked by the dpa. For this reason, the federal states are in close contact with each other, and solutions are being sought together with the federal government. Lower Saxony is currently chairing the Conference of Environment Ministers.

If the shortage of precipitants worsens, it cannot be ruled out that the operation of the sewage treatment plants will be disrupted, the ministry warned. If the situation does not improve in the foreseeable future, the water authorities were given the option of exceeding the phosphate limit values ​​- for the time of the exceptional situation. Corresponding “notes and regulations” were sent to the water authorities, limited in time until October 31st. Other federal states are likely to follow, wrote the "Spiegel".

shortage of hydrochloric acid

According to the report, the reason for the delivery difficulties is a shortage of hydrochloric acid, mainly due to high energy prices. Hydrochloric acid is a basic product for the production of precipitants.

The German Chemical Industry Association (VCI) explained how dramatic the supply situation for hydrochloric acid is at the moment cannot be assessed due to the lack of production data on individual substances. In principle, the extremely high gas and electricity prices are forcing the chemical industry to severely reduce its production. If individual raw materials were only produced to a limited extent, this would have far-reaching consequences for the downstream stages of the value chain.

Fertilizer for aquatic plants and algae

Phosphates have no direct toxic effect on people and the environment, but they act as fertilizers for aquatic plants and algae, a ministry spokeswoman said. If excessive phosphate gets into the water with the wastewater, this can lead to increased growth of algae in the water. Algae blooms, on the other hand, can cause great damage because they remove a lot of oxygen from the water - fish and other animals could die and the water overturn.

Therefore, everything must be done to keep the impact on the rivers as low as possible, the spokeswoman made clear. In the event of delivery failures, the sewage treatment plant operators should also check whether the operation can be switched to alternative precipitants or whether the use of precipitants can be reduced in order to bridge the time until the next delivery.

NEXT NEWS