Ohtlike ainete eemaldamine sademeveest

Selle töö eesmärk oli leida lahendus sademevee puhastamiseks raskmetallidest, selleks et vältida võimalikku keskkonnakahju. Selleks uuriti antud töös raskmetallide saaste põhjuseid ja võrreldi erinevaid veepuhastuse meetodeid, et valida kõige sobivam lahendus konkreetse ettevõtte jaoks. Samuti analüüsiti erinevate veepuhastusmeetodite eeliseid ja puudusi. Töös käsitleti järgmisi sademevee puhastustehnoloogiaid: • keemiline koagulatsioon ja flokulatsioon; • ioonvahetus; • pöördosmoos; • elektroforees; • fitoremediatsioon; • aktiivsüsi. Töös võrreldi sademevee proovide tulemusi keskkonnakvaliteedi piirnormidega, et tuvastada võimalikud põhjused, miks normid teatud tingimustel ületati. Selleks esitati joonised, mis kajastavad raskmetallide sisaldust erinevates sademevee väljalaskudes. Joonistelt (Joonis 7, Joonis 9, Joonis 10, Joonis 11, Joonis 12) selgusid piirkonnad, kus raskmetallide kontsentratsioon ületas lubatud norme ning selle põhjal tehti järeldusi raskemetallide võimalikest saasteallikatest. Lisaks esitati töös ettepanekuid, kuidas vähendada raskmetallide sisaldust sademevees, analüüsides selleks erinevate saastainete võimalikke põhjuseid. Kõige sobilikumaks tehnoloogiaks osutus aktiivsöeprotsess, sest tegemist on suhteliselt odava lahendusega ning seda on lihtne opereerida. Aktiivsöe filtri eeliseks on ka selle universaalsus, sest lisaks raskmetallide eemaldatakse mitmed muud ohtlikud ühendid. Lihtsustatud puhastusskeem (Joonis 16) koosneb ühtlustusmahutist, eelpuhastusest ja aktiivsöefiltrist.

Nowadays the subject of environmental preservation is of enormous topical importance. In this regard, industrial companies must realize the scale of the impact of their activities on the environment and take measures to prevent potential ecological risks, including managing rainwater runoff. The topic of this thesis is “Hazardous Substances Removal from Rainwater”. The aim of this study is to find a solution for cleaning stormwater from heavy metals, using as an example a company engaged in shipbuilding and repair, metal processing, mechanical engineering and providing port services. To achieve this goal, various types of water purification and their pros and cons have been studied. The thesis examines the following methods: • chemical coagulation and flocculation; • ion exchange; • reverse osmosis; • electrophoresis; • phytoremediation; • activated carbon. The practical part of the work includes analyzing the samples of rainwater for the year 2022. During the study, excess concentrations of various heavy metals such as zinc, barium, copper, and nickel were identified. Diagrams (Joonis 7, Joonis 9, Joonis 10, Joonis 11, Joonis 12) were used to visualize the data, reflecting the level of heavy metal content at various discharge points into bodies of water. The analysis of the diagrams made it possible to identify the areas where the content of heavy metals exceeded permissible norms and to make conclusions about possible causes of this phenomenon. The thesis also includes proposals for reducing the level of heavy metals in rainwater, taking into account the company's activities, as well as a description of its activities and weather conditions in the area. The aim of this work has been achieved and a solution for cleaning stormwater from heavy metals for the company has been found and justified. It was proposed to use a method with activated carbon, which is universal, fast, simple, accessible, suitable for reuse, and has a low impact on the environment (Tabel 3). To ensure the highest efficiency, it was decided to combine this method with precipitation. The results of the study would help the company become more environmentally friendly and solve problems of managing stormwater. This solution can contribute to the promotion of more environmentally friendly and sustainable methods of production in general.