Characteristics of Sewage 行銷你的想法是很具挑戰性的，首先你必須讓聽眾大體上同意你的想法，然後你必須刺激他們開始行動，透過卡內基訓練® 證據 – 行動 – 利益公式，你就可傳達一個激發性且行動性的簡報。 2019/7/17

Outline Strength of sewage Properties of sewage Physical properties Chemical properties Oxygen Demands (BOD, COD) Use of BOD, BOD test Solids in sewage Biological Properties 2019/7/17

Strength of Sewage Odour, colour, turbidity Suspended Solid (SS) Biochemical oxygen Demand (BOD) Chemical Oxygen Demand (COD) Oxygen absorbed (OA) Chlorine demand 2019/7/17

Properties of Sewage Physical properties Chemical properties Biological properties 2019/7/17

Physical properties a) Colour b) Odour c) Temperature d) Turbidity 2019/7/17

Chemical Characteristics Chlorine Nitrogen Oxygen PH value Total solids 2019/7/17

Oxygen Demand It is the demand of oxygen to oxidise both organic and inorganic matters ThOD - Theoretical Oxygen Demand COD - Chemical Oxygen Demand BOD - Biochemical Oxygen Demand 2019/7/17

ThOD - Theoretical Oxygen Demand theoretical amount of oxygen 2019/7/17

COD - Chemical Oxygen Demand oxidizing the waste with a boiling acid dichromate solution 2019/7/17

BOD - Biochemical Oxygen Demand the amount of oxygen required for the oxidation of a waste by bacteria 2019/7/17

Uses of BOD Polluting power of sewage or its nuisance value The load of organic matter on the sewage treatment plants The amount of clean diluting water required for disposal of sewage 2019/7/17

BOD Test A sample of the sewage is taken and added to specially prepared diluting water which has an excess of oxygen. The sample is incubated of 5 days at 20C. a sample of diluting water called blank solution is also incubated in the same way. The oxygen remaining in the both is determined and difference give the oxygen consumed, i.e. the value of BOD or BOD5. 2019/7/17

COD TEST The BOD test gives a good picture of the amount of organic matter in a stream. However, the test required a minimum of 5 days. The chemical oxygen demand (COD) test determines the oxygen requires for chemical oxidation of organic matter by using a strong chemical oxidant. 2019/7/17

COD TEST The COD test involves oxidation by an acid with potassium dichromate. A measured amount of dichromate is added to sample in the presence of sulphuric acid and it is boiled for two hours. It is then cooled and the amount of dichromate remaining is measured is titration with ferrous ammonium sulphate. The dichromate consumed gives the oxygen required for oxidation of organic matter. 2019/7/17

Solids Sewage Total solids Suspended and dissolved solids Settleable solids 2019/7/17

Biological Characteristics Develop culture medic in an incubator at specified temperature and for a specified time View with a microscope for the type and quantity of the bacteria 2019/7/17