Ozonation treatment for Dipy effluent Trial Report

Client: Dr. Reddy’s Laboratories Ltd,Bachupalli,Hybd.

Presented byMr. Beema Rao – sr.Project Manager

Ozonation System

Ozone

• Ozone or trioxygen, is a triatomic molecule consisting of three oxygen atoms. It is an allotrope of oxygen that is much less stable than the diatomic allotrope (O2), breaking down in the lower atmosphere to normal dioxygen

• Ozone is used effectively in the processing of water laden with concentrations of industrial byproducts. Pesticides, organics, BOD and COD are all treated thoroughly and effectively through ozone oxidation.

Physical properties of ozone

Formula : O3

Colour : Colourless gas

Melting point : -193 C

Boiling point : -112 C

Density : 2.14 g/ltr.

Solubility in water @ 20 C : 0.381 ltr. O3 /ltr water

Solubility in water @ 60 C : 0 ltr O3 /ltr water

Strong UV adsorption @ 254 nm

Other properties of ozone• Ozone at atmospheric conditions is highly unstable and reduces to oxygen. It

has a half life of 20 minutes in water and 60 minutes in air

• Decay products of ozone are environmentally safe

• Ozone is a colourless gas, 1.5 times heavier than oxygen

• It has a very pungent smell at as low a concentration as 0.03 ppm in air

• Ozone is a very powerful oxidising agent and hence a very potent disinfectant. It is over 3000 times more powerful than chlorine in its disinfective property and over 50 times more powerful in its oxidative property. While undergoing reduction reaction, ozone reduces to oxygen,

which makes it one of the most environment friendly treatment reactions

Ozone as a micro-Flocculant• Ozone acts as a micro-flocculant. Oxidation of

dissolved organics with ozone results in polar and charged molecules that react with polyvalent aluminium or calcium to form precipitates.

• This also improves in settling property of the particles at as low a dosage of 0.5 ppm.

• The precipitate can be removed by filtration thereby reducing the suspended particles in water. This results in decrease in turbidity.

Electro-chemical Oxidation Potential (EOP): The table below compares the electro-chemical oxidation potential (EOP)

of various oxidants

FLUORINE 3.06 V

HYDROXYL RADICAL 2.80 V

OXYGEN (ATOMIC) 2.42 V

OZONE 2.08 V

HYDROGEN PEROXIDE 1.78 V

HYPOCHLORITE 1.49 V

CHLORINE 1.36 V

CHLORINE DIOXIDE 1.27 V

OXYGEN (MOLECULAR) 1.23 V

Dipy Effluent Treatment By ozone

Dipy Effluent Dipyridamole is one of the intermediate process of Dr. Reddy’s

laboratories ltd, Bhauchpalli, hybd. In this process, waste water generated is called Dipy Effluent.

• The colour of this effluent is dark turbid yellowish green• The dissolved content of the effluent vary between 160 and

180 mg/l• The pH of the effluent is some times acidic ranging between

3.5 to 4.5 and sometimes neutral.• Total suspended solids of the effluent is between100 ppm to

2000ppm.• Turbidity of the effluent is between 500 to 1600ppm.• The BOD and COD of the effluent vary from 15000-25000 mg/l

and 25000-60000 mg/l respectively

Treatment of Dipy effluent

The Dipy Effluent (200lts) is collected in collection tank.

Then the Effluent is sent to ozone reaction tank and ozonised for duration of 1 hr,1 hr 45 minutes and 2 hrs.

After 2 hrs of Ozonation crystal clear colour treated effluent is obtained.

Since ozone is a powerful oxidizing agent the COD is reduced up to 98.51% (As per Dr.Reddy’s lab report).

The treated water can be used for process and gardening.

Trial Report

Raw Effluent Quality:1.COD: 23,500 ppm2.TSS: 641ppm3.Turbidity: 355 ppm4.PH: 6.85.TDS: 172 ppm6.Colour: Dark turbid yellowish green

Trial Report

Treated Effluent Quality (after 1 hr ozonation): 1. COD: 2133 ppm 2. colour: pale green 3. TSS: 98 ppm 4. Turbidity: 38 ppm 5.TDS: 200 ppm 6.PH: 6.8 7. %COD reduction: 91

Trial Report

Treated Effluent Quality (after 1.45 hr ozonation)1.COD: 360 ppm2.TSS: Nil3.Turbidity: Nil4.TDS: 180 ppm5.colour: crystal clear6. %COD reduction: 98.6

Ozonation process description• Oxygen concentrator: Purified oxygen generated from atmospheric air by

pressure swing adsorption principle

• Ozone generator: Purified oxygen is passed through ozone generator where corona discharge within ozone cell converts a part of oxygen gas into ozone gas

• Ozone gas mass transfer system: Ozone gas is injected and mass transferred in to water by specially designed venture injectors

• Ozone reaction tank: Ozone reaction tank is a state of art mass transfer and reaction tank for dissolving ozone as well as carry out the oxidation reactions of the organics for COD and BOD reductions. Treated water can then be transferred further for physical treatment depending upon waste water quality

• Note: Ozone dosage in mg/l depends upon the waste water quality

Advantages of ozonation system

• Ozone system is compact and space requirement is less

• Sludge can be reduced up to 99% and above • COD, BOD, colour, odour,TOC,Turbidity reduction as

per PCB norms • Maintenance and labour costs are low • There are no chemical costs when treated with ozone • Very low cost on civil works

Picture shows effluent before treatment and after treatment – pharmaceutical

Treatment scheme

Effluent transfer pump

ozone reaction tank

Oxygen generator

Ozonator

Ozone

ozonation system

Ozonation feed pump

Collection tank

Filter feed pump

Pressure sand filter-

Treatedwater tank (Client’s scope)