Choosing a suitable method for the treatment of industrial phosphoric acid waste liquid needs to consider a variety of factors, such as the concentration of waste liquid, emissions, the content of harmful substances, treatment costs, etc. The following are some considerations for choosing a suitable treatment:

1. Concentration and treatment capacity of waste liquid: for high concentration industrial phosphoric acid waste liquid, chemical precipitation method, activated carbon adsorption method and other methods can be selected for treatment; for low concentration industrial phosphoric acid waste liquid, evaporation concentration method and other methods can be selected for treatment. At the same time, the treatment capacity is also an important consideration in selecting the treatment method, and it is necessary to select the appropriate treatment method according to the discharge amount of the waste liquid.
2. Content of harmful substances: For industrial phosphoric acid waste containing harmful substances, it is necessary to select treatment methods that can remove these harmful substances, such as biological treatment, oxidation-reduction method, etc.
3. Processing cost: Different processing methods require different equipment and materials, so processing cost is also an important consideration in selecting a processing method. When choosing a treatment method, it is necessary to consider its long-term operating costs, including equipment maintenance, renewal and other costs.
4. Environmental protection requirements: When treating industrial phosphoric acid waste, relevant laws, regulations and standards should be followed to ensure that the treatment effect meets environmental protection requirements.
5. Safety issues: When choosing a treatment method, it is also necessary to consider safety issues to avoid secondary pollution or harm to operators during the treatment process.

In summary, the selection of a suitable method for the treatment of industrial phosphoric acid waste liquid needs to consider a variety of factors, including the concentration of waste liquid, emissions, the content of harmful substances, treatment costs, environmental protection requirements and safety issues. In practical applications, experimental methods can be used to compare various treatment methods to determine the optimal treatment scheme.