M.Sc

Islamic Azad University

Science and Research Campus

Thesis for Master Degree in Environmental

Water and Weast Water Engineering

Title: The technical and economic comparison of in the industrial treatment plant

in the Tehran industrial estate

Supervisors Professor :

Dr Borghei Mahdi

Dr Hasani Amir hesam

Advisors Professor :

Dr Mir Bagheri Seyed Ahmad

Dr Javid Amir Hossein

By: Reza Mirzaee

Feb 2010

......

........

............................................................................................................

(EA-AS)

(AB)

MBBR

(SBR)

(ICEAS)

(IFAS)

USBF

(UASB)

(UAFB)

(UABR)

(Contact Process)

SAGB

(

ICEAS

USBF

UASB

BOD5

COD

TSS

BODCODTSS

BOD5

COD

TSS

BOD5CODTSS

BOD5

COD

TSS

BOD5CODTSS

COD

TSS

BOD5

COD

TSS

BOD5CODTSS

BOD5

COD

.

TSS

..

BODCODTSS

BOD5

COD

TSS

BOD5CODTSS

BOD5

COD

BOD5COD

BOD5

COD

TSS

BOD5CODTSS

COD

TSS

COD

TSS

CODTSS

COD

TSS

BOD5

COD

TSS

BOD5

COD

TSS

BOD5

COD

TSS

BOD5

COD

TSS

BOD5CODTSS

COD

TSS

BOD5

COD

TSS

COD

TSS

BOD5

COD

TSS

BOD5CODTSS

BOD5

COD

TSS

pH

BOD5

COD

TSS

pH

BOD5

COD

TSS

pH

COD

TSS

pH

BOD5

COD

TSS

pH

BOD5

COD

TSS

pH

BOD5

COD

TSS

pH

BOD5

COD

pH

BOD5

COD

TSS

pH

COD

TSS

pH

COD

TSS

pH

BOD5

COD

TSS

pH

BOD5

COD

TSS

pH

BOD5

COD

TSS

pH

BOD5

COD

TSS

pH

COD

TSS

pH

BOD5

COD

TSS

pH

COD

TSS

pH

BOD5

COD

TSS

pH

UAFBPH

PHUAFB

UAFB

AB

PHUAFB

PH

PH,COD,BOD,TSS

QCOD,BOD,TSS,

UAFB

PH PH

PH

PHPHPH

PH

PH

PH PH

PH

ON-LINE PHSupernatant PH

PH

PH

PH AB

The technical and economic comparison of in the industrial treatment plant

in the Tehran industrial estate

By : Reza Mirzaee Supervisors :

Dr Borghei Mahdi

Dr Hasani Amir hesam Advisers :

Dr Mir Bagheri Seyed Ahmad

Dr Javid Amir Hossein

Abstraction

Based statistical analysis and site viewing it could be declared in this research that all the waste water treatment processes which applied in waste water treatment plants of industrial cities are combined and biological treatment approaches. At the present time all plants are in service with a reasonable efficiency. So consequently we can say that anaerobic reactors have good efficiency and reliability in encountering Hydraulic shocks and organic loads and also economic, but they are weak and inefficient in acidic effluents so it is recommended:

The acidic effluents shall be neutralized prior to discharge to anaerobic reactors or anaerobic reactors mustn t used for acidic effluents. Also it can be neutralized or be raised to

pH or beyond in equalization tank. The Low pH on line alarm system must be installed in entrance of plant. A recycle stream must be applied

Supernatant - from aerobic more than

pH - to entrance of system . The volume of this recycle line has to be calculated in designing process to avoid lack of retention times.

Lime or alkaline dosing shall be installed prior to equalization tank for neutralization.

The acceptable waste water draining limitations for plants in industrial cities is

.

it shall be upgraded to 7 or upper.

In case of low organic loads it is recommended to use extended aeration or AB reactors

The main criteria for discharging the output of water treatment plants to surface waters or for irrigation are the standards of Environment Organization of Iran. These qualitative and quantitative criteria are pH, COD, BOD, and TSS. The basic fact witch designers use to design the industrial cities waste water treatment plants is the organic load. It means the designs and calculations are in the base of Flow, TSS, BOD, COD and the volumes of reactors are neither huge (noneconomic) and nor small (not capable). Though using high efficiency anaerobic reactors - up stream

powered by media ( UAFB ) in the first stage of plants is very common. This kind of design is very powerful against organic and hydraulic shucks. The second stage is usually an aerobic or activated sludge system. The combination of these two stages has a very high recovery

%. The main disadvantage of this system is the poor resistivity against low pH waste water, because the volume of anaerobic reactors has not any significant roll against acidic streams. The organic reactions in anaerobic reactor decrease the pH approximately one degree. This occurs due to acid production reactions. So when a low pH

less than

effluent enters to anaerobic reactor reduces the pH to less than

and stops the methane producer bacteria s activity and consequently the reactor will work malfunction. For example in Aq Qala waste water treatment plant anaerobic reactor eliminated and only the aerobic reactor employed , this system has a powerful resistance to acidic shocks because the reactor has always

or higher pH and an efficient equivalence with air to remain neutral. So consequently we can say that anaerobic reactors have good efficiency and reliability in encountering Hydraulic shocks and organic loads and also economic, but they are weak and inefficient in acidic effluents so it is recommended:

The effluent s pH shall be noticed carefully, if it has an acidic situation it must be neutralized or another approach must be chosen, prior to discharge to anaerobic reactors. With reference to stated facts the effluent must has a

pH or beyond in equalization tank prior to discharge to anaerobic tank.

The following steps are proposed for neutralization: The Low pH on line alarm system must be installed in entrance of plant.

A recycle stream must be applied

Supernatant - from aerobic more than

pH - to entrance of system. The volume of this recycle line has to be calculated in designing process to avoid lack of retention times.

Lime or alkaline dosing shall be installed prior to equalization tank for

neutralization.

The acceptable waste water draining limitations for plants in industrial cities is

it shall be upgraded to 7 or upper.

In case of low organic loads it is recommended to use extended aeration or AB reactors