Health, Safety and The Environment

Water treatment technology is a mix of chemical, biological, mechanical and electrical processes working in unison usually controlled by a PLC and based on a civil infrastructure.

Protecting people and the environment is of ultimate importance in water treatment. Safety First is a common slogan in many power stations and water treatment plants.

Chemical hazards in water treatment plants includes personal or environmental exposure to harsh chemicals such as acids, bases, and coagulants, toxic chemicals such biocides and hazardous chemicals such as slippery flocculants. Mixing of incompatible chemicals is another hazard. For example, mixing acids and bases can generate a large amount of heat. The reaction between acid and metal can generate Hydrogen which is an explosive gas and can require ATEX equipment. Ofcourse, last but not least sometimes flammable fuels such as diesel fuel are used in power stations and this represents a fire and environmental hazard. MSDS = Material Safety Data Sheets are of utmost importance to knowing the chemical properties of chemicals and how to react in case of an accident. Safety Signs are also very important for warning people about hazards. Confined space is one hazard to watch out for in manholes, underground basins and so forth. Drowning in aeration basins is a real hazard in waste water treatment plants because aerated water has a weak boyant force.

Biological hazards include exposure to disease causing harmful bacteria and viruses such as Legionella. Biological water treatment can also produce methane gas which is explosive when mixed with air. In this case ATEX rated equipment is used.

Electrical and mechanical hazards are also everywhere in water treatment plants. Normally medium voltage is used to power mechanical equipment and this can kill. Mechanically moving parts such as pump couplings present a mechanical hazard.

Compiled by Rami E. Kremesti M.Sc.