Projektowanie zakładu uzdatniania wody przy wsparciu modeli laboratoryjnych

Abstrakt

The subject of the research focused on the possibilities of supporting the design of surface water treatment plants using laboratory models. Within the pilot study, the possibilities of using different water treatment processes in the treatment of water from the water reservoir Nové Mlýny in the Czech Republic were assessed. The planned treatment plant is to supply a future recreational site from a shallow reservoir with significant eutrophication and chemical industry in the drainage basin. Coagulation, sedimentation, dissolved air flotation, membrane filtration processes and adsorption on granular activated carbon were investigated. These processes were identified by the preliminary study as applicable to water treatment and it was necessary to determine which could be applied given the site conditions. Laboratory models for the individual processes were used during the laboratory testing. During the research, problems encountered were debugged and the models were modified and some extensions were added to the original models. The coagulation and sedimentation processes were investigated using conventional jar tests. The dissolved air flotation process was simulated using a modified jar test and a lab scale model. Different types and doses of coagulants, mixing parameters and residence times were investigated in the tests. Turbidity value was used as an optimization parameter due to its rapidity of determination and low cost. For some tests, potassium permanganate oxidizability (also known as the permanganate index) was also used as an evaluation parameter so that different evaluation parameters could be compared. In addition, for the dissolved air flotation process, the parameters of the produced sludge - its quantity, suspended solids content and chemical oxygen demand - were monitored. These parameters are crucial for discharge of waste water into the sewer and its costs. The adsorption tests on granular activated carbon were performed as batch tests. The evaluation parameter was the manganese index. Another possible variant of activated carbon tests is a continuous flow-through column. These columns also allow monitoring of the process of fouling and the evolution of the effluent over time. The pilot project then used the results of the laboratory tests to create a design for a treatment plant in the area of interest and selected parts of the project documentation. The pilot project demonstrated the usefulness of laboratory testing as a tool to support the design of drinking water treatment plants. At the same time, these tests allow for a faster and more certain identification of the appropriate water treatment technology and thus reduce the extent of semi-operational testing at the site, leading to a more efficient use of funds by investors.