Faecal Sludge Management

4. OPERATION AND MANAGEMENT:

Sanitation employees:

Are those who are in charge of cleaning, maintaining, operating, or emptying sanitation technology at any point along the sanitation chain. These employees help to ensure that faecal sludge is handled safely.

Cities:

FSM is a key sanitation service in all cities and towns where onsite sanitation systems are used by houses. Citywide FSM initiatives may rely on numerous or a single treatment facilities, permanent and mobile transfer stations, and partnerships with micro, small, and medium-sized businesses to provide some or all of the services. To meet rising demand, programmes may be brought in over time.

Rural areas:

If the traditional norm is to cover and replace latrines when they fill up, rural areas with low population density may not require formal FSM services. If this is not practicable, rural locations frequently lack treatment facilities within a reasonable (say 30 minute drive) distance; are difficult for tankers to access; and frequently have minimal demand for emptying, making transportation and treatment uneconomic and costly for most people. As a result, options like relocating latrines on-site or installing multiple (alternating) pit toilets may be considered. Decentralized FSM services and sludge treatment between surrounding settlements, as well as direct safe waste removal burial, should be investigated and organised.

4.1 SELECTING THE OPERATOR OF FSM SERVICES:

Local governments, water authorities, and utilities are the most common providers of FSM services. FSM programmes are logical operators for water utilities that have a high percentage of water connectivity (homes with piped water connections). If clients purchase water through a tariff, a separate tariff for FSM services may be added. The most appropriate operator for larger cities is usually the water and sewerage service provider.

For collection, transportation, and treatment, local governments may choose to use their own employees and resources. This is frequently the case in smaller cities or municipalities where the water utility’s reach is limited. Collaboration between the local government and the water provider can be strategically beneficial in many circumstances. The FSM programme is jointly owned and managed in Dumaguete City, Philippines, by the Water District (utility) and the Local Government. On a bigger scale, organised Independent private operators working on an ad hoc basis may be able to deliver the service more inexpensively and hygienically than FSM programmes. When promoting the programme to citizens and encouraging them to participate, ensuring that services are affordable is a key selling factor. FSM services are largely provided by the private sector in the local area. In such instances, private sector contractors may work directly for homes (as long as they follow the rules) or bid on the city’s desludging contracts. The private sector can also help with the operation and maintenance of the treatment plants, as well as the processing and sale of the products that arise from the treatment process. San Fernando City in the Philippines is an example of a municipal government that has outsourced services.

4.2 TRANSPORT OPTIONS:

Vehicles and equipment for collection:

If the faecal sludge is liquid enough, vacuum pumps or centrifugal style booster pumps are used to collect it. There are a range of manual and motorised devices on the market for excavating thick and viscous sludge and collected rubbish.

The accumulated sludge in septic tanks and pit latrines hardens with time and becomes exceedingly difficult to remove. Despite the fact that entering pits to desludge them is generally risky and unwelcome, employees continue to do so (in India, this practise is called “manual scavenging”). There are a number of low-cost pumping systems available to remove this hardened sludge from the ground surface in a sanitary manner, albeit many are still in the experimental stage.

The “in-pit lime stabilisation procedure,” which treats the waste before it is evacuated from the tank or pit, can also be used to treat faecal sludge inside the tank or pit. In 2010, iDE Cambodia was the first to use this methodology. It is then transferred to treatment and processing facilities, either on-site or off-site.

Some modern transfer stations and vacuum trucks can partially dewater faecal sludge, and this water can then be pumped into sewer systems and cleaned at wastewater treatment plants. This allows for more sludge to be handled more efficiently, and it may be one of the best examples of faecal sludge co-treatment in wastewater treatment plants.

Transfer stations:

Transfer stations are drop-off locations that are frequently utilised when treatment facilities are too far away from population centres to allow for direct disposal. Other places may be able to accommodate transfer stations due to traffic problems or municipal truck bans during daylight hours. In addition, towns with a large number of households that are not accessible by tanker truck should use transfer stations.

Transfer stations are utilised if the following conditions exist:

• A vacuum truck cannot reach more than 5% of the residences;
• The treatment plant is too far away from the homes to deliver in one haul;
• Trucks are not permitted on the streets during the day;
• Heavy traffic obstructs the movement of vacuum trucks during daylight hours.

A) Mobile transfer stations: Mobile transfer stations are just larger tanker trucks or trailers with tiny vacuum trucks, motorcycles, or hand carts deployed beside them. The sludge is collected by the smaller vehicles and transported to the treatment plant by the larger tanker. These perform well in business models that involve scheduled desludging.

B) Fixed transfer stations: Fixed transfer stations are designated drop-off places for collected faecal sludge that are strategically located around the municipality. A receiving station with screens, a tank to hold the collected waste, garbage storage bins, and wash down facilities are just a few examples. These may be more suited to FSM programmes that operate on a “call-for-service” basis.

Mobile transfer stations, unlike static transfer stations, are essentially tanker trucks or trailers that work with SVVs to transport garbage from the community to the treatment plant over longer distances. Where there is no traffic, mobile transfer stations function well for scheduled desludging procedures.

limits or truck bans, as well as a disproportionately large number of houses inaccessible to larger vehicles.

4.3 TREATMENT PROCESSES:

A) Traditional treatment processes: Fecal sludge is frequently processed via a series of treatment procedures to separate the liquids from the solids, then treat both the liquid and solid trains to recover as much energy or nutritional value as possible.

The following are some of the most common procedures used in faecal sludge treatment plants:

• Fecal sludge receiving – the point at which the truck meets the treatment plant and the sludge is unloaded.
• Primary treatment – simple separation of liquid and solids by physical means (dewatering and thickening), e.g. with drying beds, to remove rubbish, sand, grit, and FOG (fats, oil, and grease).
• Liquids treatment – employing artificial wetlands, waste stabilisation ponds, and anaerobic digesters, for example.
• Solids processing – putting the solids produced by faecal sludge treatment to good use.

B) Sludge drying beds: Simple sludge drying beds can be used for dewatering and drying faecal sludge since they are a cheap and simple procedure (they are also widely used to dry sewage sludge). Drainage water must be collected; drying beds are sometimes covered, but most of the time they are left exposed.

In most cases, drying beds have four levels (from top to bottom):

• Sludge
• Sand (about 10-15 cm) (sometimes with wires or plastic mesh on top of it, to prevent it being removed when the dried sludge is extracted)
• 10 centimetres of fine gravel
• Drainage pipes and 15-20 cm of coarse gravel.

During the dewatering process, faecal sludge behaves differently from wastewater sludge. The amount of extracellular polymeric substances (EPS) in faecal sludge can be a good predictor of how well it dewaters. Fecal sludge from public restrooms took longer to dewater than sludge from other sources, and after settling, it had a murky supernatant.

Grasses with adventitious roots can also be planted in drying beds, which allows for less odour, longer collection times, forage production, and more decomposition of the final biosolids by the time they are collected. The roots maintain the permeability of the sludge by introducing oxygen. In such settings, earthworms may also play a significant role.

C) Solar thermal dryers: For drying and pasteurisation of faecal sludge, solar thermal dryers collect solar thermal energy. The sludge is contained within a transparent or opaque enclosure with a ventilation system for moisture removal in these systems. The sludge can be dried using hot air heated by a solar thermal collector (indirect solar dryer), direct solar radiation (direct solar dryer), or a combination of the two (mixed solar dryer).

Collection of Sludge

The waste sludge is collected in a sludge drying bed that is generated by the ETP. The waste sludge is stored in 12 drying beds. Sludge is removed from the holding tank and dumped on the bed.

1. Using a sucking machine to collect human faeces.
2. Transferring it to the huge tank, where it will be kept for 41 days.
3. combine the water and the human waste

Settling–thickening Tank

For FS treatment, a rectangular settling–thickening tank is employed. Solids settle at the bottom of the tank, whereas scum floats on the surface. The FS is discharged via a top inlet on one side and the supernatant escapes through an outlet on the other side; solids settle at the bottom of the tank, however scum floats on the surface (Strande et al., 2014). The addition of lime/ammonia straight into the settling–thickening tank could be an alternative for treating FS. Lime stabilisation from wastewater sludge treatment has the benefits of precipitating metals and phosphorus, as well as lowering pathogens, smells, degradable organic matter, and other contaminants (Mendez et al., 2002); it has been used in the Philippines for FS treatment (Pescon & Nelson, 2005). Ammonia treatment can also be used to reduce pathogens.It is a technology that is relatively strong and resilient, although it has a low pathogen reduction rate. Sedimentation tank waste cannot be dumped into bodies of water or utilised directly in agriculture.

Brick making

For the purposes of this investigation, adequate brick solidification is required. To get good strength, the right proportion of different types of material must be used. The dry homogeneous mixture is made after selecting the right percentage for brick. After adding the required amount of water, a moist homogeneous slurry is created, and the mortar is then used to make brick samples.

Advantages of Using Sludge Bricks

• Good stamina. Bricks that are environmentally friendly.
• Water absorption is less than 15% in 24 hours. 1 pound of bearing bricks
• High quality at a low price. In masonry work, you can save money by using less cement. Reduce the construction costs.
• Cement use should be reduced by 20%.

5. RESULTS

The conclusion is based on the results of many experimental sets and experiments. WTP sludge (water treatment plant sludge) could be used to substitute traditional brick reinforced with sludge waste from industry, which has a high chromium concentration.

The researched brick type will be a strong contender in the market against cement and clay bricks.

In the 20 percent sludge substitution in bricks, the maximum compressive strength was obtained.

1. Set 1 (60 percent quary dust, 20% cement, and 20% sludge) can be suitable for structural purposes.
2. Set2 (60 percent quarry dust, 10% cement, and 30% sludge) can be suitable for non-structural uses.
3. Set3 (50 percent quarry dust, 20 percent cement, and 30 percent sludge) could be used for non-structural purposes.
4. Set4 (20% quary dust, 30% cement, and 50% sludge) is unsuitable for structural and non-structural applications.

6. FUTURE SCOPE:

• It is necessary to increase one’s strength.
• It should be cost-effective.
• Materials that are both inspiring and inventive should be used.
• Determining the exact ratio that will be practical.
• Cement volume is reduced.

7. REFERENCES:

1. Milivoj petrik: Utilisation of night soil sewage and sewage sludge in agriculture( in 1954)
2. Muhammad Ashraf Ali :Fecal sludge management in urban ares of Bangladesh(in 2015)
3. Emmanuel Alepo Odey: Fecal sludge management In developing Urban centre review on the collection, treatment and composting ( in 2017 )
4. Peter M Hawkins: Fecal sludge management a comparitive analysisof 12 cities (in 2014)
5. Charles Niwagaba: Faecal sludge as fuel in industrial kilns for brick production (in 2015)
6. Jackson, N. and R.K. Dhir, 1996. “Civil Engineering Materials”, Fifth Edition, Mac Millan Education LTD,London
7. Feenstra, L., J.G.T. Wolde and C.M. Eenstroom, 1997. “Reusing Water Treatment Plant Sludge as Secondary Raw Material in Brick Manufacturing”, Studies in Environmental Science, 71: 641-645.