ppt SEWERAGE SYSTEM

BFC 35303

SEWERAGE SYSTEM

Ts. Dr Roslinda Seswoya

EVOLUTION OF SEWERAGE SYSTEM IN MALAYSIA 01

TABLE OF CONTENTS

POPULATION EQUIVALENT 02

03

SEWAGE TREATMENT

BUFFER ZONE 04

01 EVOLUTION OF SEWERAGE SYSTEM IN MALAYSIA

Country Sanitation Assessment in Malaysia Report, Japan Sanitation Consortium (JSC),2011

RS FKAAB, 2023

01 EVOLUTION OF SEWERAGE SYSTEM IN MALAYSIA

PRIMITIVE/ PRIMARY TREATMENT (1950 – 1960s)

In the early days in Malaysia, people have no concern and aware on the waste discharge which might lead to a serious problem such as health issues

Due to lack of technology development at the time, people tend to discharge their waste directly into the stream or built a containment area such as the pour flush concept

The pour flush concept was a hole like” individual septic tank’ being digging

down beneath the soil layer at certain depth and all the waste discharged accumulated inside

Then at certain time or the storage has reach its maximum capacity. The

process of desludging begins

01 EVOLUTION OF SEWERAGE SYSTEM IN MALAYSIA

01 EVOLUTION OF SEWERAGE SYSTEM IN MALAYSIA

01 EVOLUTION OF SEWERAGE SYSTEM IN MALAYSIA

Malaysia's most common form of sewerage system is the individual septic tank (IST). IST has 3 to 4

rectangular metal covers and is usually located outside the premises compound either at the side, rear or front.

The septic tank only provides partial treatment of the sewage that flows into it and needs to be desludged on a regular basis to ensure that it functions efficiently

Sewage is the wastewater from bathrooms and toilets from households and commercial premises.

It is also referred to as sewage or brown water and can carry disease and bacteria, both of which could be harmful.

01 EVOLUTION OF SEWERAGE SYSTEM IN MALAYSIA

Septic tank diagram ^RS FKAAB, 2023

01 EVOLUTION OF SEWERAGE SYSTEM IN MALAYSIA

Imhoff Tanks (IT) are simple form of sewage treatment plants requiring very little operator skill.

There is no mechanical equipment to maintain and operation consists of removing scum, reversing the flow to keep an even distribution of sludge and removing sludge

IT provide limited treatment of sewage and are not a suitable long-term

solution. The effluent from Imhoff tanks can rapidly deteriorate if the tanks are not properly maintained

PARTIAL/SECONDARY TREATMENT (1970 – 1990s)

01 EVOLUTION OF SEWERAGE SYSTEM IN MALAYSIA

An IT comprises two chambers positioned one above the other. In the upper compartment sedimentation occurs with solids passing through an opening into the lower chamber.

01 EVOLUTION OF SEWERAGE SYSTEM IN MALAYSIA

Heavier solids settle at the bottom of the tank as sludge.

Sludge in the lower chamber undergo anaerobic digestion that producing methane

Gases from the lower tanks are discharged to the air.

Scum is accumulated in the upper tank.

Scum

01 EVOLUTION OF SEWERAGE SYSTEM IN MALAYSIA

OPs may comprise one or more shallow ponds in a series. The natural processes of algal and bacteria growth exist in a mutually dependent relationship.

OPs require large amounts of land and the degree of treatment is weather dependent.

They are incapable of achieving a good standard of effluent consistently

Oxidation pond or stabilization pond

Oxidation Ponds (OP) (or Stabilisation Ponds) are a popular sewage treatment method for small communities because of their low construction and operating costs

.

01 EVOLUTION OF SEWERAGE SYSTEM IN MALAYSIA

Aerated Lagoons (AL) are relatively simple plants to operate and maintain. However, they require large land areas and are therefore rarely found in densely populated urban areas.

The AL process normally comprises two or three lagoons in a sequence. The first lagoon has surface aerators, which are like large "paddle mixers". The aerators float on the surface of the pond and continuously stir the incoming sewage, serving to maintain oxygen content in the sewage and preventing any solids from settling. Effluent is passed into the second pond where the degraded organic matter and sediments are settle out to form sludge. The

effluent may then pass to a third pond for polishing or be discharged to a receiving waterway.

01 EVOLUTION OF SEWERAGE SYSTEM IN MALAYSIA

Sewage has an average retention in the first pond of five days. During this time, bacteria consumed the oxygen to breaking down the organic material in the sewage. The

average retention time in the second pond is one day.

Care must be taken in managing the settling pond in warm climates. These ponds can suffer from algal growth and/or odour generated by anaerobic digestion of the sludge at the bottom of the pond.

01 EVOLUTION OF SEWERAGE SYSTEM IN MALAYSIA

SECONDARY TREATMENT / FULLY MECHANISED PLANT (1990 – 2000s)

Pantai 1 Centralised Sewage Treatment Plant ( Activated Sludge Process for PE of 377000 )

02 SEWAGE TREATMENT

Preliminary Treatment

Preliminary sewage treatment is defined as the removal of sewage constituents that may cause maintenance or operational problems with the treatment operations. This includes screening and comminution (grinding) for the removal of debris and rags, grit removal by sedimentation and flotation for the removal of excess oil and grease.

Primary Treatment

In primary treatment screening and sedimentation remove some of the suspended solids and organic matter. The effluent from primary treatment will contain high amounts or organic matter.

Secondary Treatment

Secondary sewage treatment is directed at the removal of biodegradable organic and suspended solids, mainly using biological unit processes.

http://www.aozhouiwk.com/sewage-treatment-methods.html

02 SEWAGE TREATMENT

Tertiary Treatment

Tertiary sewage treatment includes the removal of nutrients, toxic substances including heavy metals and further removal of suspended solids and organic. Effluent from tertiary treatment is of a high standard and suitable for reuse.

There is no plan to build tertiary treatment systems in Malaysia. The focus has been providing a basic standard of preliminary, primary and secondary treatment.

http://www.aozhouiwk.com/sewage-treatment-methods.html

02 SEWAGE TREATMENT

MALAYSIAN SEWERAGE INDUSTRY GUIDELINES (MSIG) , VOLUME 4 STPS

–SECTION 5

02 SEWAGE TREATMENT

MALAYSIAN SEWERAGE INDUSTRY GUIDELINES (MSIG) , VOLUME 4 STPS

–SECTION 5

02 SEWAGE TREATMENT

MALAYSIAN SEWERAGE INDUSTRY GUIDELINES (MSIG) , VOLUME 4 STPS –SECTION 5

02 SEWAGE TREATMENT

Biological treatment is the heart of the sewage treatment process. It is the processes where the dissolved and non- settleable organic material remaining in the sewage are removed by living organisms.

Because the success of biological processes depends on the environment provided by treatment units, design engineers need a basic understanding of factors affecting the growth of mixed cultures.

In biological treatment system, the microorganism are divided into the followings:

1) Suspended growth- microorganisms and bacteria treating the wastes are suspended in the wastewater being treated.

2) Attached growth- microorganisms and bacteria treating the wastes are attached to the media in the reactor

02 SEWAGE TREATMENT

For reasons of long term whole life economics, ease of operation and maintenance, consistent effluent standards and standardisation, the following types of biological treatment processes are recommended for use in Malaysia.

Suspended Growth System

a) Conventional activated sludge (CAS) system

b) Extended aeration (EA)/Oxidation Ditch (OD) System

c) Sequencing Batch Reactor (SBR)/Intermittent Decant Extended Aeration (IDEA) Attached Growth System

a) Rotating biological contactor (RBC) system b) Trickling filter (TF) System

c) Hybrid System/Combination multistage design

02 SEWAGE TREATMENT

All plants must be strictly designed to meet DOE Standard A/Standard B requirements including, nitrification and denitrification to reduce ammonia and total nitrogen removal Total phosphorus removal must also be taken into account for plants where treated effluent is to b e discharged into stagnant water bodies.

Mass balance calculation must be computed and submitted for all biological treatment system and other unit processes proposed for the STP.

RS

02 SEWAGE TREATMENT

SUSPENDED GROWTH SYSTEM

Stabilization Pond Activated Sludge

02 SEWAGE TREATMENT

ATTACHED GROWTH SYSTEM

Trickling filter

Rotating biological contactor (RBC)

02 SEWAGE TREATMENT

Rotating biological contactor (RBC)

02 SEWAGE TREATMENT

The stabilization of organic material (pollutant) is accomplished by microbes which convert colloidal and dissolved organic matter into gasesand protoplasm

organic material + Microbes Gases + new cell (protoplasma) (colloidal & dissolved)

major requirements for microbial growth a) A terminal electron acceptor

b) Macronutrients:

i) Carbon to build cells ii) Nitrogen to build cells

iii) Phosporus for ATP (energy carrier) and DNA c) Micronutrients

i)Trace metals

ii) Vitamins (required for some bacteria d) Appropriate environment

i) Moisture ii) Temperature iii) pH

02 SEWAGE TREATMENT

Decompositionis the process by which organic substances are broken down into simplerorganic matter.

It can accomplished is three ways 1) Aerobic

2) Anoxic 3) Anaerobic

02 SEWAGE TREATMENT Aerobic Decomposition

Large production because large amount of energy released

• generates a large production of sludge (dead and living cells). Therefore, it is suitable for low strength wastewater (ie < 500 mg/l BOD) because decomposition is rapid, efficient and has a low odor potential.

• For high strength wastewater(>1000 mg/l BOD), aerobic decomposition is not suitable because of difficulty in supplying of enough oxygen and also because of the amount of sludge produced

.

• Occurs in the presence of oxygen as the terminal electron acceptor

organic matter + O

₂

→ CO

₂

+ H

₂

O + newcell

02 SEWAGE TREATMENT

Anoxic Decomposition (nitrogen removal)

• A biological process in which a certain group of microorganisms use chemically combined oxygen such as that found in nitrate (NO^-₃).

• Anoxic conditions involve environments in which molecular or free oxygen (O₂) is absent, though bound oxygen may be present ( eg NO₃-)

• NO^-₃ is used as the terminal electron acceptor in the absence of molecular oxygen.

2NO^-₃ + 2H⁺ → N₂ + 2.5 O₂ + H₂O + new cell

• Because the biodegradation of nitrogen products naturally releases oxygen, the bacteria in anoxic tanks like denitrification basins do not require supplemental oxygen from diffusers or surface aerators.

02 SEWAGE TREATMENT

During anaerobic degradation,

microorganisms break down organic matter in the absence of oxygen.

The anaerobic decomposition of organic matter considered to be a four -step process (figure):

These anaerobic process often occur in an airtight, enclosed

bioreactor filled with sludge. Sludge contains anaerobic bacteria and other beneficial microbes.

Processes in anaerobic degradation

Anaerobic Decomposition

03 POPULATION EQUIVALENT (PE)

In order to design pipe network, pump stations and sewage treatment plants, estimates need to be made of the volumetric flow rate which will be expected to be carried, pumped and treated.

Such flow rates are measured in cubic metres per second and need to be calculated for both existing land use and for expected future development.

There are many methods for calculating expected flow rates. One method is to calculate a design parameter called the "population equivalent" (PE) of a catchment and convert this to a flow rate.

The PE is an estimate of the usage made of sewage facilities. It is not a measure of population.

For residential areas the population equivalent is calculated as five per dwelling and is a direct measurement of the population in an area.

However for commercial areas it is calculated from the floor area, which is considered to be proportional to the number of people using a premises during the day. In this case it does not reflect the population living in an area.

03 POPULATION EQUIVALENT (PE)

MALAYSIAN SEWERAGE INDUSTRY GUIDELINES (MSIG) , VOLUME 4 STPS –SECTION 1

03 POPULATION EQUIVALENT (PE)

MALAYSIAN SEWERAGE INDUSTRY GUIDELINES (MSIG) , VOLUME 4 STPS –SECTION 1

EXAMPLE 1

Considering the information in the advertisement board of a construction project ( as

shown ) and the bill of quantities (BQ), determine the population equivalent (PE) for the purposed project

Answer:

Item From Advertisement From BQ PE ( using PE recommended) A 663 unit service apartment

115 unit apartment 663 unit x 5 PE/unit = 3315 115 unit x 5 PE/unit = 575

B Common area

Car park ( 9 storey) 1500 m²

5000 m² 1500 m² x 3 PE/100 m² = 45 5000 m² x 3 PE/100 m² = 150  PE = 4085

Calculate the population equivalent (PE) for the proposed project using

Table 1. Item From

Advertisement From BQ 1 Wholesale

Food court Shopping mall Children

playground Electrical substation

5000m² 2000m² 5000m²

5000m² / 100 children

-

2 Wholesale Office Store

5000 m² 900 m² 2000m²

Worship = 100m² / place 30 person Table 1

EXAMPLE 2

Item From Advertisement From BQ PE

Recommended

1

Wholesale 5000m² Food court 2000m² Shopping mall 5000m²

Children playground 5000m² or 100 children Electrical substation ^-

2

Wholesale 5000 m²

Office 900 m²

Store 2000m²

Worship place = 100m² or 30 person TOTAL PE Answer

03 POPULATION EQUIVALENT (PE)

Sewage treatment plants are also classified in accordance to the design capacity in terms of population equivalent (PE) as shown below

MALAYSIAN SEWERAGE INDUSTRY GUIDELINES (MSIG) , VOLUME 4 STPS –SECTION 2

03 POPULATION EQUIVALENT (PE)

The recommended land area requirements for various sewage treatment plants capacities are derived from relevant treatment process concepts and also taken into consideration other design criteria.

The land area requirements and buffer allowance for temporary sewage treatment plants maybe reduced at the discretion of the Commission on a case by case basis.

Class 1 and 2 Plants

The recommended land area requirements for Class 1 and 2 plants (up to 5000 PE) are given in Table 4.2 and Table 4.3 respectively. The net area does not include the 30 m buffer zone surrounding the plant, but does include appropriate set backs and access paths within the plant.

The area requirements given are sufficient to achieve an effluent conforming to Standard A discharge requirements. It is important that allowance is made for sufficient buffers in planning approvals, to avoid future complaints in relation to the siting of the plant.

MALAYSIAN SEWERAGE INDUSTRY GUIDELINES (MSIG) , VOLUME 4 STPS –SECTION 4

03 POPULATION EQUIVALENT (PE)

MALAYSIAN SEWERAGE INDUSTRY GUIDELINES (MSIG) , VOLUME 4 STPS –SECTION 4

03 POPULATION EQUIVALENT (PE)

MALAYSIAN SEWERAGE INDUSTRY GUIDELINES (MSIG) , VOLUME 4 STPS –SECTION 4

03 POPULATION EQUIVALENT (PE)

Mechanised Class 3 to 4 Plants

For Class 3 and 4 plants with mechanised systems, the recommended land area requirements are given in Table 4.4 and 4.5. These systems are to be used in normal developed and urbanised areas.

The net area does not include the 30 m buffer zone surrounding the plant, but does

include appropriate set backs and access paths within the plant.

The area requirements given are sufficient to achieve an effluent conforming to Standard A discharge requirements. It is important that allowance is made for sufficient buffers in

planning approvals, to avoid future complaints in relation to the siting of the plant.

MALAYSIAN SEWERAGE INDUSTRY GUIDELINES (MSIG) , VOLUME 4 STPS –SECTION 4

03 POPULATION EQUIVALENT (PE)

MALAYSIAN SEWERAGE INDUSTRY GUIDELINES (MSIG) , VOLUME 4 STPS –SECTION 4

EXAMPLE 3

A new development is proposed. Determine the population equivalent (PE), plant treatment capacity and the required land area. Use the followings:

Houses = 286 unit

Market = 15 stall ( wet) and 15 stall ( dry) Commercial area ( gross area) = 1000 m²

Answer

1. Using recommended PE, then PE for

Houses = 286 unit = 286 x 5 PE = 1430 PE Market = 15 stall ( wet) = 15 x 3 PE = 45 PE = 15 stall ( dry) = 15 x 1 PE = 15 PE

Commercial area ( gross area) = 1000 m² = 1000 m² X 3 PE = 10 PE 100 m²

Total PE = 1500

2. Use table plant treatment capacity (Table 2.1) and PE of 1500, then the STP is classified as Class 2

3. Use table land area requirement for Class 2 (Table 4.3) and PE of 1500, then the required area for STP development is 1275 m² ( 0.315 acre)

05 BUFFER ZONE

Suitable buffer distances should separate a sewage treatment plant from its surrounding areas.

The provision of buffer zones is essentially an environmental requirement controlled by the relevant planning authority. The agreement of the Local Planning Department on buffer zone and plant siting should be sought at an early stage in the Town and Country planning

procedures.

The buffer zone requirements for treatment plants to be observed under this Guideline are as follows. Refer Figures 4.3 and 4.4

a) Minimum distance of 30 m from the fence of the treatment plant to the nearest habitable building property line within residential and commercial development.

b) Minimum distance of 20 m from the fence of the treatment plant to the nearest property line within industrial development.

c) Minimum distance of 10 m from the fence of the treatment plant to the nearest habitable building property line if the proposed treatment plant is fully enclosed. A fully enclosed plant is defined in section 7.3.1.

MALAYSIAN SEWERAGE INDUSTRY GUIDELINES (MSIG) , VOLUME 4 STPS –SECTION 4

04 BUFFER ZONE

d) A minimum distance of 10 m from the fence of the treatment plant to the nearest habitable building property line if the proposed treatment plant is covered or buried.

However, this reduction in buffer requirement does not apply if the nearby habitable buildings are of high rise type. A covered or buried plant is defined in section 7.4.1.

e) Plants with PE less than 150 but are provided with proper odour and noise mitigation measure may have a 10 m reduced buffer at the discretion of the Commission.

The buffer zone can be used for any purpose except permanent habitable buildings. For example, the buffer zone maybe used as a drainage reserve, road or highway reserve, transmission reserve, utility reserve or public park.

In the case where buffer area is to be regularly used by the residents such as car park and playgrounds, proper precautions during design stage must be taken to minimise nuisance such as odour, noise and unpleasant sight to the surrounding environmentl. Adequate and proper screening, odour containment and treatment facilities must be provided

at the sewage treatment plant to address these issues.

MALAYSIAN SEWERAGE INDUSTRY GUIDELINES (MSIG) , VOLUME 4 STPS –SECTION 4 RS FKAAB, 2023

04 BUFFER ZONE

MALAYSIAN SEWERAGE INDUSTRY GUIDELINES (MSIG) , VOLUME 4 STPS –SECTION 4 RS FKAAB, 2023

04 BUFFER ZONE

MALAYSIAN SEWERAGE INDUSTRY GUIDELINES (MSIG) , VOLUME 4 STPS –SECTION 4

EXAMPLE 4

Open treatment plant (sewage treatment plant) is proposed in the residential area of a new development area ( Example 1). Determine the buffer zone.

Answer

Referring to Guideline of Buffer zone ( Figure 4.3). The buffer zone distance with habitable building is minimum 30 m.

—https://www.thestar.com.my/metro/metro- news/2021/05/24/iwk-dirty-habit-leads-to-heavy-costs

“POO, pee and toilet paper are the only items that should be

flushed down the toilet. However, Malaysians have been flushing

more than the 3Ps down their toilets.

Indah Water Konsortium Sdn Bhd (IWK) chief executive officer Narendran Maniam said an average of 40,000 tonnes of rubbish end up in its sewerage treatment system every year.

“From sanitary pads, wet wipes, and condoms to cigarette butts, cat

litter, medicine, diapers and hair are thrown into the toilets and

these items clog and contaminate our sewerage systems.

“IWK treatment plants can only treat sewage

TUTORIAL

Q1. Considering the information in the advertisement board of a

proposed project (as shown ) and Table 1,determine the population equivalent (PE).

From Advertisement From BQ

Hospital ward = 76 beds Office = 500m²

Public toilet = 15 unit Food court = 2000m²

Children playground = 50 children Common area = 1000 m²

Worship place = 50 person

Table 1

TUTORIAL

Q2. Using calculated PE from 1) Example 2, and 2) Q1, Tutorial recommend the required area for sewage treatment plant (STP) for each site.

THANK YOU!