Operational Procedures in Hotel Services - Sewage Treatment Plant Effluent Tests

Preventing the back-flow of sewage gases into accommodation areas

May destroy essential bacteria in aerobic treatment plants

To remove and prevent the build-up of toxic and flammable gases

<p>Rapid depletion of oxygen in the water, causing aerobic bacteria to be unable to survive.</p> Signup and view all the answers

<p>Anaerobic bacteria.</p> Signup and view all the answers

<p>Methane, ammonia, and hydrogen sulphide.</p> Signup and view all the answers

<p>The gases are both toxic and flammable, posing serious health and safety risks.</p> Signup and view all the answers

<p>It results in the production of black, turgid water.</p> Signup and view all the answers

<p>The rapid depletion of oxygen in the water.</p> Signup and view all the answers

<p>The main risk is from the toxicity of the gases.</p> Signup and view all the answers

<p>The BOD test is carried out by incubating a sample of the effluent in the dark at 20°C for 5 days. The amount of oxygen consumed by the microorganisms in the sample during this period is measured. The reason for this test is to determine the amount of oxygen required to break down the organic matter in the effluent, which is an indicator of the effluent's impact on the receiving water body.</p> Signup and view all the answers

<p>The Suspended Solids test is carried out by filtering a sample of the effluent through a pre-weighed filter paper and then drying the filter paper to determine the weight of the suspended solids. The reason for this test is to measure the amount of solid material suspended in the effluent, which can have an impact on the receiving water body.</p> Signup and view all the answers

<p>The Coliform Count test is carried out by culturing a sample of the effluent on a selective growth medium that allows for the identification and enumeration of coliform bacteria. The reason for this test is to determine the presence and level of fecal contamination in the effluent, which can indicate the potential presence of pathogenic microorganisms.</p> Signup and view all the answers

<p>The plant should emit a slightly earthy smell. A rotten egg smell indicates the process has become anaerobic.</p> Signup and view all the answers

<p>The normal colour of the aerated floc should be a rich chocolate, while the liquid flowing over the weir to the final collection tank should be clear when viewed through the observation ports.</p> Signup and view all the answers

<p>The level of water above the dark brown floc in a measuring tube or gauge should not be excessive.</p> Signup and view all the answers

<p>The pH value of the effluent should be within the optimal range for the treatment process, typically between 6.5 and 8.5.</p> Signup and view all the answers

<p>The correct range of free chlorine level in the final discharge is 1-3 ppm.</p> Signup and view all the answers

<p>A sample of the clean effluent is taken and a test kit reagent is added. The sample is then compared to a test color, and once the colors match, the reading for chlorine can be taken and recorded.</p> Signup and view all the answers

<p>The IMO regulations specify the distances from land where sewage can be discharged, in order to protect the marine environment.</p> Signup and view all the answers

<p>Testing allows adjustments to be made to the sewage treatment process, which helps to optimize the treatment and ensure the final discharge meets the required standards.</p> Signup and view all the answers

<p>The use of large quantities of disinfectant toilet cleaners should be avoided, as they can have a detrimental effect on the biological processes within the sewage treatment plant.</p> Signup and view all the answers

<p>The purpose of adequate water seals on lavatory pans, showers, and washbasins is to prevent the backflow of sewage gases into the living spaces, which can be hazardous to human health.</p> Signup and view all the answers

<p>Adequate air vents should be fitted to the piping network to allow for the proper ventilation of the system, preventing the buildup of hazardous sewage gases.</p> Signup and view all the answers

<p>A comparator test can be used to ascertain the level of free chlorine being discharged from the sewage treatment plant. By comparing the sample of the clean effluent to a test color, the operator can determine the exact chlorine level and ensure it is within the required range.</p> Signup and view all the answers

<p>The residual chlorine level in the discharge from an approved sewage treatment plant is an important indicator of the effectiveness of the treatment process. The level must be within the specified range to ensure the treated effluent is safe for discharge into the environment.</p> Signup and view all the answers

<p>The disinfection tank eliminates bio-organisms from the effluent using a membrane filtration process, eliminating the need for chlorination.</p> Signup and view all the answers

<p>Non-biodegradable materials are removed by the self-cleaning filter.</p> Signup and view all the answers

<p>The blower pumps air through airlines to the diffusers at the bottom of the aeration tank, supplying oxygen to stimulate the growth of aerobic bacteria.</p> Signup and view all the answers

<p>The settling tank allows suspended solids, such as plastics, to be trapped after they have been screened out of the aeration tank.</p> Signup and view all the answers

<p>The use of membrane filtration in the disinfection tank eliminates the need for chlorination, allowing the plant to comply with legislation regarding effluent treatment.</p> Signup and view all the answers

<p>Retaining and circulating the aerobic bacteria between the tanks maintains their maximum effectiveness in digesting the sewage.</p> Signup and view all the answers

<p>If there are separate lines for black and grey water, the grey water can enter the unit directly through the top of the disinfection tank.</p> Signup and view all the answers