TOPIC: SUSTAINABLE WASTEWATER TREATMENT

• sick water or contaminated water

• domestic effluent

• industrial effluent

• agricultural , horticultural and aquaculture effluent

• storm water and urban runoff from the urban area

• sewage water

Categories of sources of wastewater:

• Domestic wastewater

• Industrial / commercial wastewater

Wastewater can be divided into three types:

• Blackwater

• Greywater

• Yellow water

• Refers to the flows of discharged from residential area sources

• Eg: food preparation, laundry, cleaning and personal hygiene

(bathing) which consist of blackwater and graywater

• Flow generated and discharged from the manufacturing and commercial activities

• Eg: printing, food and beverage processing and production

• Wastewater that containing feces, urine and flushwater from

flush toilets along with cleansing water or toilet paper.

• Wastewater that come from domestic equipment other than toilets

• Preferred to kept separate from blackwater to reduce the amount of water that get heavily polluted

• Plant nutrient

• Pathogenic microorganisms

• Heavy metals

• Organic pollutant

• Biodegradable organics

• Micro-pollutants

• Malaysia nation sewerage organization

• Operation (under IWK) cover 88 of 144 local authorities in Malaysia

1. Health and hygiene

2. Environment and natural resources

3. Technology and operation

4. Financial and economic issue

5. Socio-cultural and institutional aspect

• Process that modifies wastewater characteristics BOD, COD,PH etc. to enable it met effluent standards.

• Stage one : screening

• Stage two : primary treatment

• Stage three : secondary treatment

• Stage four : final treatment

• Screening remove huge and large particles.• This includes the division of natural strong matter (or

human waste) from the wastewater. • Sump and pump house - wastewater is used to collect in the

sump and pump to a higher tank treatment• Approach channel - to dampen the flow of wastewater pumped to

treatment plant units• Screen chamber- to remove the large particles• Grit chamber- to remove remaining solid material• Skim chamber- to remove oil and grease from the wastewater

Primary (mechanical) treatment is intended to remove gross,

suspended and skimming solids from crude sewage. It consist

screening to trap strong items and sedimentation

by gravity to expel suspended solids.

This is finished by putting the wastewater into huge settlement tanks

for the solids to sink to the base of the tank. The settled solids are

called 'sludge'.

• Use biological process to get the broke down organic matter

missed in preliminary treatment.

• The main purpose is used to reduce BOD.

• The level of oxygen in the wastewater is changed at different

stages - to produce aerobic and anaerobic environments.

• Around 85% of the suspended solids and BOD can be expelled

by a well running plant with secondary treatment.

• Then, Secondary treatment advances consists the secondary

initiated sludge process, the variations of lake and built wetland

frameworks, streaming channels and different types of

treatment which use biological activity to separate organic

matter.

• Lagoon: A wastewater treatment that uses ponds to treat water. They communicate with the interaction of algae, microorganisms, sunlight, and also oxygen to break down the organic matter.

• Main purpose: to reduce nitrogen and phosphates which can cause serious problems when they get into water to speed up the growth of algae blooms.

• Can remove more than 99 percent of the considerable number of pollutants from sewage, creating an emanating of just about

drinking-water quality.

The tertiary treatment system is mostly provided while:

1. The quality of standard treated wastewater is improper for the

final disposal requirement.

2. the concentration of remaining organic materials or suspended

solids require removal for particular reuse of wastewater after

the secondary treatment.

3. the concentration of remaining nutrients is high for final

treatment or reuse of wastewater

1. Treatment of wastewater• Objective: to reduce the level of pollutants in the

wastewater before discharge it.• Improper treated wastewater has a significant

impact towards human health and ecosystem.

2. Reuse and recycling water● A survey by Xylem Inc. in California in 2016: 76% believe

recycled water should be used as a long-term solution for managing water resources. Nearly half or 49% are very supportive of using recycled water as an additional local water supply and another 38% are somewhat supportive.

● Example: drinking water, agriculture, aquaculture, construction, landscaping and etc.

3. Wastewater collection● Centralised system: a large-scale system that gather

wastewater from many users for treatment at one or few sites.

● Decentralised system: an on-site system that dealing with wastewater generated from small group of users at the neighbourhood or small community level.

● Decentralised systems require well trained staffs and high cost of maintenance to handle the system

4. Prevention and awareness● Responsible authorities should take part by enforcing the laws and policies

regarding wastewater consumed by netizens.● Every person in community regarding their ages should be educate with

awareness campaign to encourage them in the reduction of the excessive amount of wastewater production.

• Enhance and upgrading the quality of life

• Preserve and protect natural environment

• Waste reduction – saving and processing water

• Energy and production fertilizer

• Can prevent any damages

• High capital cost

• Public perception

• Various chemical substances and waste product from the

process

• Health concern

● Does not have a proper sewage disposal and drainage system

● Impact the environment and citizen’s health.

● - Increase the number of plant treatment● - Opinion : Decentralized treatment.

5321

1)-Sedimentation tanks for retaining particle -Dissolved & suspended matter passes untreated to next treatment stage.

2)-Anaerobic -Sludge (activated) at the bottom of each chamber -Further treatment (degradation) of suspended & dissolved solid by bacteria

4)-Aerobic -Concentrate more on removal of smell and color -Consist of plants (reed) and filter material (graded gravel, river pebbles, etc.)

5)-fit with aquatic plants and fishes. -Transform from lifeless state into living water again -continuous oxygen supply to the water

Septic Tank Anaerobic Baffled Reactor

Planted gravel Filter

Polishinng Pond

Anaerobic bed filter 4

3)-Anaerobic -filter is made up of gravel, slag or plastic element

• High population• Lack of clean water sources

• Have to import clean water from neighbouring country,Malaysia• High cost

• Reclaimed water treatment• NEWater (product)

1. Wastewater is collected and treated in Water Reclamation Plant.2. Uses of microfiltration or ultrafiltration to filter out suspended solid,

colloidal particles, disease-causing bacteria, virus and protozoa lumps.

3. In reverse osmosis stage, undesirable contaminated such as bacteria, virus, heavy metal, nitrate, chloride, sulphate and etc. are filtered out using semi permeable membrane

4. In ultraviolet disinfection stage, all microorganism is inactive and purity of the product is guaranteed.

5. The water is ready once the alkaline chemical is added to restore the pH balance.

Smells excessively from the sewage treatment plant• Have to check that the sewage treatment plant has the right

ventilation or not • if not the gases might build inside the pipework and tank to

cause the excessive odours.

Aging infrastructure and workforce• Most common problem that faced by the wastewater treatment plant system• Pipelines , tunnels , storage , pumping and treatment facilities• Can affect the quality of recycle water• Lack of worker skill and experience because the whole

process is complicated and need further research

Funding concern • Spend a huge capital for operational cost, facilities,

workforce and research.

• Government intervention - support the system• Financial planning - contribute to the system - efficiency

Blockage in sewer pipe• Caused by the disposal of objects such as solid

waste ,rags etc.

• Manholes and toilets being overflowed• Create pollution to the environment• Threaten to public’s health

• Upgrade pump station

• Optimize aeration

• Improve sludge management

• Recover essential nutrients

• Go light on disinfection

• Update lighting and HVAC systems

• Maximize gravity

1. Upgrade pump station• Older pump might be slow / damaged

• Older pump design to operate one speed only

• Newer pump can produce long hour operating time

2. Optimize aeration• By upgrading to a bigger blower

• Replace aging / spoil blower to achieve higher

• Changing diffuser system to fine pore / ultra-fine pore, will increase oxygen transfer & reduce air needed

3. Improve sludge management• 20% or more energy are used

• In order to improve it, minimize the transport of solids and water by optimizing biogas for heating and electricity

4. Recycle essential nutrients

• Phosphorus is an important compound in fertilizers mixture

• Biological phosphorus removal create a marketable graded fertilizer

• New source of revenue for the plant

5. Go light on Disinfection• Ultraviolet light disinfection system replace disinfectant

• To eliminate costly & harmful chemical

• Minimal energy used & use of hazardous chlorine disinfectant reduce

6. Update lighting & HVAC systems

• Consumes a lot of energy• Update fluorescent lighting fixtures to new high-efficiency

fixtures in the plants

7. Maximize gravity• All the process that uses pump or motor can be reduced

• Let the gravity to do its job

● Create water quality standard➢ Set a minimum target requirement➢ Use chemical substances that more biodegradable

● Create awareness among society➢ Implementation of rules and regulations➢ Provide campaign and talk➢ Highly advertise in social media

● Benchmark➢ Follow and copy standard procedure from proven organizations➢ Enhance and improve control strategies

● Maintain the efficiency of worker as well as machineries in treatment plant➢ Apply regular examine and inspection session➢ Set standard precaution throughout whole process

● Hire high standard professional worker to operate the system➢ To train domestic worker

● Expand and develop new technology and facilities○ Use new green technology