T.8 Sedimentation and Thickening Ponds

Sedimentation or Thickening Ponds or tanks are settling ponds that allow sludge to thicken and dewater. The effluent is removed and treated, while the thickened sludge can be further treated in a subsequent technology.General term for a liquid that leaves a technology, typically after blackwater or sludge has undergone solids separation or some other type of treatment. Effluent originates at either a collection and storage or a (semi-) centralised treatment technology. Depending on the type of treatment, the effluent may be completely sanitised or may require further treatment before it can be used or disposed of.Mixture of solids and liquids, containing mostly excreta and water, in combination with sand, grit, metals, trash and/or various chemical compounds. A distinction can be made between faecal sludge and wastewater sludge. Faecal sludge comes from on-site sanitation technologies, i.e. it has not been transported through a sewer. It can be raw or partially digested, a slurry or semisolid, and results from the collection and storage/treatment of excreta or blackwater, with or without greywater. Wastewater sludge (also referred to as sewage sludge) originates from sewer-based wastewater collection and (semi-)centralised treatment processes. The sludge composition will determine the type of treatment that is required and the end-use possibilities.Describes technologies for on-site collection, storage, and sometimes (pre-) treatment of the products generated at the user interface. The treatment provided by these technologies is often a function of storage and is usually passive (i.e. requires no energy input), except a few emerging technologies where additives are needed. Thus, products that are ‘treated’ by these technologies often require subsequent treatment before use and/or disposal. In the technology overview graphic, this functional group is subdivided into the two subgroups: “Collection/Storage” and “(Pre-)Treatment”. This allows a further classification for each of the listed technologies with regard to their function: collection and storage, (pre-) treatment only or both.Refers to the methods through which products are returned to the environment, either as useful resources or reduced-risk materials. Some products can also be cycled back into a system (e.g. by using treated greywater for flushing).A functional group is a grouping of technologies that have similar functions. The compendium proposes five different functional groups from which technologies can be chosen to build a sanitation system:
User interface (U), Collection and Storage/Treatment (S), Conveyance (C), (Semi-) Centralised Treatment (T), Use and/or Disposal (U).
A sanitation system is a multi-step process in which sanitation products such as human excreta and wastewater are managed from the point of generation to the point of use or ultimate disposal. It is a context-specific series of technologies and services for the management of these sanitation products, i.e. for their collection, containment, transport, treatment, transformation, use or disposal. A sanitation system comprises functional groups of technologies that can be selected according to context. By selecting technologies from each applicable functional group, considering the incoming and outgoing products, and the suitability of the technologies in a particular context, a logical, modular sanitation system can be designed. A sanitation system also includes the management and operation and maintenance (O & M) required to ensure that the system functions safely and sustainably. The utilisation of products derived from a sanitation system.
A sanitation system in which excreta and wastewater are collected and stored or treated on the plot where they are generated.
The means of safely collecting and hygienically disposing of excreta and liquid
wastes for the protection of public health and the preservation of the quality of public water bodies and, more generally, of the environment.

Waste matter that is transported through the sewer.
An open channel or closed pipe used to convey sewage. See C.3 and C.4
Used water from any combination of domestic, industrial, commercial or agricultural activities, surface runoff/stormwater, and any sewer inflow/infiltration.

Faecal sludge is not a uniform product and, therefore, its treatment must be specific to the characteristics of the sludge. Sludge which is rich in organics and has not undergone significant degradation is difficult to dewater. Conversely, sludge that has undergone significant an aerobic degradation is more easily dewatered. In order to be properly dried, fresh sludge, which is rich in organic matter (e.g. latrine or public toilet sludge), must first be stabilised, which can be done through an aerobic degradation in Sedimentation/ Thickening Ponds. The same type of pond can be used to thicken sludge which is already partially stabilised, e.g. originating from Septic Tanks S.13 . The degradation process may hinder the settling of sludge because the gases produced bubble up and re-suspend the solids. As the sludge settles and digests, the supernatant must be discharged and treated separately. The thickened sludge can then be dried or co composted T.9 T.10 T.11 .

Describes biological processes that occur in the presence of oxygen.
Decomposed organic matter that results from a controlled aerobic degradation process. In this biological process, microorganisms (mainly bacteria and fungi) decompose the biodegradable waste components and produce an earth-like, odourless, brown/black material. Compost has excellent soil-conditioning properties and a variable nutrient content. Because of leaching and volatilisation, some of the nutrients may be lost, but the material remains rich in nutrients and organic matter. Generally, excreta or sludge should be composted long enough (2 to 4 months) under thermophilic conditions (55 to 60 °C) in order to be sanitised sufficiently for safe agricultural use.Consists of urine and faeces that are not mixed with any flushwater. Excreta is relatively small in volume, but concentrated in both nutrients and pathogens. Depending on the characteristics of the faeces and the urine content, it can have a soft or runny consistency.Refers to (semi-solid) excrement that is not mixed with urine or water. Depending on diet, each person produces approximately 50–150 L per year of faecal matter of which about 80 % is water and the remaining solid fraction is mostly composed of organic material. Of the total essential plant nutrients excreted by the human body, faeces contain around 39 % of the phosphorus (P), 26 % of the potassium (K) and 12 % of the nitrogen (N). Faeces also contain the vast majority of the pathogens excreted by the body, as well as energy and carbon rich, fibrous material.Refer to biodegradable plant material (organic waste) that must be added to some technologies in order for them to function properly. Organic degradable material can include, but is not limited to, leaves, grass and food market waste. Although other products in this compendium contain organic matter, the term organics is used to refer to undigested plant material.Mixture of solids and liquids, containing mostly excreta and water, in combination with sand, grit, metals, trash and/or various chemical compounds. A distinction can be made between faecal sludge and wastewater sludge. Faecal sludge comes from on-site sanitation technologies, i.e. it has not been transported through a sewer. It can be raw or partially digested, a slurry or semisolid, and results from the collection and storage/treatment of excreta or blackwater, with or without greywater. Wastewater sludge (also referred to as sewage sludge) originates from sewer-based wastewater collection and (semi-)centralised treatment processes. The sludge composition will determine the type of treatment that is required and the end-use possibilities.The liquid produced by the body to rid itself of nitrogen in the form of urea and other waste products. In this context, the urine product refers to pure urine that is not mixed with faeces or water. Depending on diet, human urine collected from one person during one year (approx. 300 to 550 L) contains 2 to 4 kg of nitrogen. The urine of healthy individuals is sterile when it leaves the body but is often immediately contaminated by coming into contact with faeces.Describes technologies for on-site collection, storage, and sometimes (pre-) treatment of the products generated at the user interface. The treatment provided by these technologies is often a function of storage and is usually passive (i.e. requires no energy input), except a few emerging technologies where additives are needed. Thus, products that are ‘treated’ by these technologies often require subsequent treatment before use and/or disposal. In the technology overview graphic, this functional group is subdivided into the two subgroups: “Collection/Storage” and “(Pre-)Treatment”. This allows a further classification for each of the listed technologies with regard to their function: collection and storage, (pre-) treatment only or both.Refers to the methods through which products are returned to the environment, either as useful resources or reduced-risk materials. Some products can also be cycled back into a system (e.g. by using treated greywater for flushing).A functional group is a grouping of technologies that have similar functions. The compendium proposes five different functional groups from which technologies can be chosen to build a sanitation system:
User interface (U), Collection and Storage/Treatment (S), Conveyance (C), (Semi-) Centralised Treatment (T), Use and/or Disposal (U).
A sanitation system is a multi-step process in which sanitation products such as human excreta and wastewater are managed from the point of generation to the point of use or ultimate disposal. It is a context-specific series of technologies and services for the management of these sanitation products, i.e. for their collection, containment, transport, treatment, transformation, use or disposal. A sanitation system comprises functional groups of technologies that can be selected according to context. By selecting technologies from each applicable functional group, considering the incoming and outgoing products, and the suitability of the technologies in a particular context, a logical, modular sanitation system can be designed. A sanitation system also includes the management and operation and maintenance (O & M) required to ensure that the system functions safely and sustainably. Simple, single cell organisms that are found everywhere on earth. They are essential for maintaining life and performing essential “services”, such as composting, aerobic degradation
of waste, and digesting food in our intestines. Some types, however, can be pathogenic and cause mild to severe illnesses. Bacteria obtain nutrients from their environment by excreting enzymes that dissolve complex molecules into more simple ones which can then pass through the cell membrane.

The process by which biodegradable components are biologically decomposed by microorganisms (mainly bacteria and fungi) under controlled aerobic conditions.
The utilisation of products derived from a sanitation system.
Any cellular or non-cellular microbiological entity capable of replication or of transferring genetic material (e.g. bacteria, viruses, protozoa, algae or fungi).
Any substance that is used for growth. Nitrogen (N), phosphorus (P) and potassium (K) are the main nutrients contained in agricultural fertilisers. N and P are also primarily responsible for the eutrophication of water bodies.
A sanitation system in which excreta and wastewater are collected and stored or treated on the plot where they are generated.
An organism or other agent that causes disease.A diverse group of unicellular eukaryotic organisms, including amoeba, ciliates, and flagellates. Some can be pathogenic and cause mild to severe illnesses.
The means of safely collecting and hygienically disposing of excreta and liquid
wastes for the protection of public health and the preservation of the quality of public water bodies and, more generally, of the environment.

Describes the conditions under which putrefaction and anaerobic digestion take place.
Waste matter that is transported through the sewer.
An open channel or closed pipe used to convey sewage. See C.3 and C.4
User interface used for urination and defecation. The organic molecule (NH2)2CO that is excreted in urine and that contains the nutrient nitrogen. Over time, urea breaks down into carbon dioxide and ammonium, which is readily used by organisms in soil. It can also be used for on-site faecal sludge treatment. See. S.18An infectious agent consisting of a nucleic acid (DNA or RNA) and a protein coat. Viruses can only replicate in the cells of a living host. Some pathogenic viruses are known to be waterborne (e.g., the rotavirus that can cause diarrheal disease).
Used water from any combination of domestic, industrial, commercial or agricultural activities, surface runoff/stormwater, and any sewer inflow/infiltration.

Design Considerations

Two tanks/ponds operating in parallel are required; one can be loaded, while the other is resting. To achieve maximum efficiency, loading and resting periods should not exceed four to five weeks, although much longer cycles are common. When a four-week loading and four-week resting cycle is used, total solids can be increased to 14 % (depending on the initial concentration). Beyond that, the quality of the supernatant may start decreasing, while sludge does not thicken further. It is also possible to have shorter cycles, for example 1 week, in order to get a sludge that is less thickened but easier to pump. The lower part of the pond is where accumulation and thickening, and thus natural compaction, takes place. The height of this zone must be estimated based on the quantity of solids to be received during the whole duration of loading and the desired final concentration. The height of the supernatant zone is typically 1 m. For an optimal design, it is recommended to test the settling capacity of the sludge beforehand. As in a Settler T.1 , the settling surface and the design of the inlet and outlet baffles are important in order to stabilise the hydraulic flow and optimise settling. The zone reserved for scum depends on the storage duration and is typically around 0.5 m. It is important that each zone’s height is well estimated in order to avoid sludge leaving the pond together with the supernatant. Access for maintenance is necessary and depends on the method planned for sludge removal.

Mixture of solids and liquids, containing mostly excreta and water, in combination with sand, grit, metals, trash and/or various chemical compounds. A distinction can be made between faecal sludge and wastewater sludge. Faecal sludge comes from on-site sanitation technologies, i.e. it has not been transported through a sewer. It can be raw or partially digested, a slurry or semisolid, and results from the collection and storage/treatment of excreta or blackwater, with or without greywater. Wastewater sludge (also referred to as sewage sludge) originates from sewer-based wastewater collection and (semi-)centralised treatment processes. The sludge composition will determine the type of treatment that is required and the end-use possibilities.Describes technologies for on-site collection, storage, and sometimes (pre-) treatment of the products generated at the user interface. The treatment provided by these technologies is often a function of storage and is usually passive (i.e. requires no energy input), except a few emerging technologies where additives are needed. Thus, products that are ‘treated’ by these technologies often require subsequent treatment before use and/or disposal. In the technology overview graphic, this functional group is subdivided into the two subgroups: “Collection/Storage” and “(Pre-)Treatment”. This allows a further classification for each of the listed technologies with regard to their function: collection and storage, (pre-) treatment only or both.Refers to the methods through which products are returned to the environment, either as useful resources or reduced-risk materials. Some products can also be cycled back into a system (e.g. by using treated greywater for flushing).A functional group is a grouping of technologies that have similar functions. The compendium proposes five different functional groups from which technologies can be chosen to build a sanitation system:
User interface (U), Collection and Storage/Treatment (S), Conveyance (C), (Semi-) Centralised Treatment (T), Use and/or Disposal (U).
A sanitation system is a multi-step process in which sanitation products such as human excreta and wastewater are managed from the point of generation to the point of use or ultimate disposal. It is a context-specific series of technologies and services for the management of these sanitation products, i.e. for their collection, containment, transport, treatment, transformation, use or disposal. A sanitation system comprises functional groups of technologies that can be selected according to context. By selecting technologies from each applicable functional group, considering the incoming and outgoing products, and the suitability of the technologies in a particular context, a logical, modular sanitation system can be designed. A sanitation system also includes the management and operation and maintenance (O & M) required to ensure that the system functions safely and sustainably. The utilisation of products derived from a sanitation system.
A sanitation system in which excreta and wastewater are collected and stored or treated on the plot where they are generated.
The means of safely collecting and hygienically disposing of excreta and liquid
wastes for the protection of public health and the preservation of the quality of public water bodies and, more generally, of the environment.

The layer of solids formed by wastewater constituents that float to the surface of a tank or reactor (e.g., oil and grease).
Waste matter that is transported through the sewer.
An open channel or closed pipe used to convey sewage. See C.3 and C.4
Used water from any combination of domestic, industrial, commercial or agricultural activities, surface runoff/stormwater, and any sewer inflow/infiltration.

Materials

This is standard civil engineering work, requiring digging and concrete. Key items are the sludge removal equipment.

Mixture of solids and liquids, containing mostly excreta and water, in combination with sand, grit, metals, trash and/or various chemical compounds. A distinction can be made between faecal sludge and wastewater sludge. Faecal sludge comes from on-site sanitation technologies, i.e. it has not been transported through a sewer. It can be raw or partially digested, a slurry or semisolid, and results from the collection and storage/treatment of excreta or blackwater, with or without greywater. Wastewater sludge (also referred to as sewage sludge) originates from sewer-based wastewater collection and (semi-)centralised treatment processes. The sludge composition will determine the type of treatment that is required and the end-use possibilities.Describes technologies for on-site collection, storage, and sometimes (pre-) treatment of the products generated at the user interface. The treatment provided by these technologies is often a function of storage and is usually passive (i.e. requires no energy input), except a few emerging technologies where additives are needed. Thus, products that are ‘treated’ by these technologies often require subsequent treatment before use and/or disposal. In the technology overview graphic, this functional group is subdivided into the two subgroups: “Collection/Storage” and “(Pre-)Treatment”. This allows a further classification for each of the listed technologies with regard to their function: collection and storage, (pre-) treatment only or both.Refers to the methods through which products are returned to the environment, either as useful resources or reduced-risk materials. Some products can also be cycled back into a system (e.g. by using treated greywater for flushing).A functional group is a grouping of technologies that have similar functions. The compendium proposes five different functional groups from which technologies can be chosen to build a sanitation system:
User interface (U), Collection and Storage/Treatment (S), Conveyance (C), (Semi-) Centralised Treatment (T), Use and/or Disposal (U).
A sanitation system is a multi-step process in which sanitation products such as human excreta and wastewater are managed from the point of generation to the point of use or ultimate disposal. It is a context-specific series of technologies and services for the management of these sanitation products, i.e. for their collection, containment, transport, treatment, transformation, use or disposal. A sanitation system comprises functional groups of technologies that can be selected according to context. By selecting technologies from each applicable functional group, considering the incoming and outgoing products, and the suitability of the technologies in a particular context, a logical, modular sanitation system can be designed. A sanitation system also includes the management and operation and maintenance (O & M) required to ensure that the system functions safely and sustainably. The utilisation of products derived from a sanitation system.
A sanitation system in which excreta and wastewater are collected and stored or treated on the plot where they are generated.
The means of safely collecting and hygienically disposing of excreta and liquid
wastes for the protection of public health and the preservation of the quality of public water bodies and, more generally, of the environment.

Waste matter that is transported through the sewer.
An open channel or closed pipe used to convey sewage. See C.3 and C.4
Used water from any combination of domestic, industrial, commercial or agricultural activities, surface runoff/stormwater, and any sewer inflow/infiltration.

Applicability

Sedimentation and Thickening Ponds are appropriate for sludge stabilisation (for example when there is fresh sludge), and/or thickening. Sludge can be thickened when difficult to dry in the raw state (for example because it is less concentrated), and/or because the climate is not conducive to open air drying, (due to high humidity or a long rainy season). Both the thickened sludge and the supernatant need further treatment, for example in drying beds or waste stabilisation ponds respectively. If a wastewater treatment plant is nearby and is able to absorb the supernatant, it can be treated there. Sedimentation and Thickening Ponds are most appropriate where there is inexpensive, available space located far from homes and businesses.

Mixture of solids and liquids, containing mostly excreta and water, in combination with sand, grit, metals, trash and/or various chemical compounds. A distinction can be made between faecal sludge and wastewater sludge. Faecal sludge comes from on-site sanitation technologies, i.e. it has not been transported through a sewer. It can be raw or partially digested, a slurry or semisolid, and results from the collection and storage/treatment of excreta or blackwater, with or without greywater. Wastewater sludge (also referred to as sewage sludge) originates from sewer-based wastewater collection and (semi-)centralised treatment processes. The sludge composition will determine the type of treatment that is required and the end-use possibilities.Describes technologies for on-site collection, storage, and sometimes (pre-) treatment of the products generated at the user interface. The treatment provided by these technologies is often a function of storage and is usually passive (i.e. requires no energy input), except a few emerging technologies where additives are needed. Thus, products that are ‘treated’ by these technologies often require subsequent treatment before use and/or disposal. In the technology overview graphic, this functional group is subdivided into the two subgroups: “Collection/Storage” and “(Pre-)Treatment”. This allows a further classification for each of the listed technologies with regard to their function: collection and storage, (pre-) treatment only or both.Refers to the methods through which products are returned to the environment, either as useful resources or reduced-risk materials. Some products can also be cycled back into a system (e.g. by using treated greywater for flushing).A functional group is a grouping of technologies that have similar functions. The compendium proposes five different functional groups from which technologies can be chosen to build a sanitation system:
User interface (U), Collection and Storage/Treatment (S), Conveyance (C), (Semi-) Centralised Treatment (T), Use and/or Disposal (U).
A sanitation system is a multi-step process in which sanitation products such as human excreta and wastewater are managed from the point of generation to the point of use or ultimate disposal. It is a context-specific series of technologies and services for the management of these sanitation products, i.e. for their collection, containment, transport, treatment, transformation, use or disposal. A sanitation system comprises functional groups of technologies that can be selected according to context. By selecting technologies from each applicable functional group, considering the incoming and outgoing products, and the suitability of the technologies in a particular context, a logical, modular sanitation system can be designed. A sanitation system also includes the management and operation and maintenance (O & M) required to ensure that the system functions safely and sustainably. The utilisation of products derived from a sanitation system.
A sanitation system in which excreta and wastewater are collected and stored or treated on the plot where they are generated.
The means of safely collecting and hygienically disposing of excreta and liquid
wastes for the protection of public health and the preservation of the quality of public water bodies and, more generally, of the environment.

Waste matter that is transported through the sewer.
An open channel or closed pipe used to convey sewage. See C.3 and C.4
The degradation of organic matter with the goal of reducing readily biodegradable compounds to lessen environmental impacts (e.g., oxygen depletion, nutrient leaching).
Used water from any combination of domestic, industrial, commercial or agricultural activities, surface runoff/stormwater, and any sewer inflow/infiltration.

Operation and Maintenance

A trained staff member for operation and maintenance is required. The maintenance is not intensive. The discharging area must be maintained and kept clean to reduce the potential of disease transmission and nuisance (flies and odours). Solid waste that is discharged along with the sludge must be removed from the screen at the inlet of the ponds PRE . The thickened sludge must be mechanically removed (with a frontend loader or other specialised equipment) after it has sufficiently thickened; alternatively, it can be pumped if it is still sufficiently liquid. It is essential to plan for sludge removal and allocate financial resources for it.

Mixture of solids and liquids, containing mostly excreta and water, in combination with sand, grit, metals, trash and/or various chemical compounds. A distinction can be made between faecal sludge and wastewater sludge. Faecal sludge comes from on-site sanitation technologies, i.e. it has not been transported through a sewer. It can be raw or partially digested, a slurry or semisolid, and results from the collection and storage/treatment of excreta or blackwater, with or without greywater. Wastewater sludge (also referred to as sewage sludge) originates from sewer-based wastewater collection and (semi-)centralised treatment processes. The sludge composition will determine the type of treatment that is required and the end-use possibilities.Describes technologies for on-site collection, storage, and sometimes (pre-) treatment of the products generated at the user interface. The treatment provided by these technologies is often a function of storage and is usually passive (i.e. requires no energy input), except a few emerging technologies where additives are needed. Thus, products that are ‘treated’ by these technologies often require subsequent treatment before use and/or disposal. In the technology overview graphic, this functional group is subdivided into the two subgroups: “Collection/Storage” and “(Pre-)Treatment”. This allows a further classification for each of the listed technologies with regard to their function: collection and storage, (pre-) treatment only or both.Refers to the methods through which products are returned to the environment, either as useful resources or reduced-risk materials. Some products can also be cycled back into a system (e.g. by using treated greywater for flushing).A functional group is a grouping of technologies that have similar functions. The compendium proposes five different functional groups from which technologies can be chosen to build a sanitation system:
User interface (U), Collection and Storage/Treatment (S), Conveyance (C), (Semi-) Centralised Treatment (T), Use and/or Disposal (U).
A sanitation system is a multi-step process in which sanitation products such as human excreta and wastewater are managed from the point of generation to the point of use or ultimate disposal. It is a context-specific series of technologies and services for the management of these sanitation products, i.e. for their collection, containment, transport, treatment, transformation, use or disposal. A sanitation system comprises functional groups of technologies that can be selected according to context. By selecting technologies from each applicable functional group, considering the incoming and outgoing products, and the suitability of the technologies in a particular context, a logical, modular sanitation system can be designed. A sanitation system also includes the management and operation and maintenance (O & M) required to ensure that the system functions safely and sustainably. The utilisation of products derived from a sanitation system.
A sanitation system in which excreta and wastewater are collected and stored or treated on the plot where they are generated.
The means of safely collecting and hygienically disposing of excreta and liquid
wastes for the protection of public health and the preservation of the quality of public water bodies and, more generally, of the environment.

Waste matter that is transported through the sewer.
An open channel or closed pipe used to convey sewage. See C.3 and C.4
Used water from any combination of domestic, industrial, commercial or agricultural activities, surface runoff/stormwater, and any sewer inflow/infiltration.

Health and Safety

Both incoming and thickened sludge are pathogenic. Workers should be equipped with proper personal protective equipment (boots, gloves, and clothing).

Mixture of solids and liquids, containing mostly excreta and water, in combination with sand, grit, metals, trash and/or various chemical compounds. A distinction can be made between faecal sludge and wastewater sludge. Faecal sludge comes from on-site sanitation technologies, i.e. it has not been transported through a sewer. It can be raw or partially digested, a slurry or semisolid, and results from the collection and storage/treatment of excreta or blackwater, with or without greywater. Wastewater sludge (also referred to as sewage sludge) originates from sewer-based wastewater collection and (semi-)centralised treatment processes. The sludge composition will determine the type of treatment that is required and the end-use possibilities.Describes technologies for on-site collection, storage, and sometimes (pre-) treatment of the products generated at the user interface. The treatment provided by these technologies is often a function of storage and is usually passive (i.e. requires no energy input), except a few emerging technologies where additives are needed. Thus, products that are ‘treated’ by these technologies often require subsequent treatment before use and/or disposal. In the technology overview graphic, this functional group is subdivided into the two subgroups: “Collection/Storage” and “(Pre-)Treatment”. This allows a further classification for each of the listed technologies with regard to their function: collection and storage, (pre-) treatment only or both.Refers to the methods through which products are returned to the environment, either as useful resources or reduced-risk materials. Some products can also be cycled back into a system (e.g. by using treated greywater for flushing).A functional group is a grouping of technologies that have similar functions. The compendium proposes five different functional groups from which technologies can be chosen to build a sanitation system:
User interface (U), Collection and Storage/Treatment (S), Conveyance (C), (Semi-) Centralised Treatment (T), Use and/or Disposal (U).
A sanitation system is a multi-step process in which sanitation products such as human excreta and wastewater are managed from the point of generation to the point of use or ultimate disposal. It is a context-specific series of technologies and services for the management of these sanitation products, i.e. for their collection, containment, transport, treatment, transformation, use or disposal. A sanitation system comprises functional groups of technologies that can be selected according to context. By selecting technologies from each applicable functional group, considering the incoming and outgoing products, and the suitability of the technologies in a particular context, a logical, modular sanitation system can be designed. A sanitation system also includes the management and operation and maintenance (O & M) required to ensure that the system functions safely and sustainably. The utilisation of products derived from a sanitation system.
A sanitation system in which excreta and wastewater are collected and stored or treated on the plot where they are generated.
An organism or other agent that causes disease.The means of safely collecting and hygienically disposing of excreta and liquid
wastes for the protection of public health and the preservation of the quality of public water bodies and, more generally, of the environment.

Waste matter that is transported through the sewer.
An open channel or closed pipe used to convey sewage. See C.3 and C.4
Used water from any combination of domestic, industrial, commercial or agricultural activities, surface runoff/stormwater, and any sewer inflow/infiltration.

Costs

Considering the land required, the construction costs and the need for sludge removal equipment, the capital costs are medium. The operating costs are low, with the major expense being the regular sludge removal.

Mixture of solids and liquids, containing mostly excreta and water, in combination with sand, grit, metals, trash and/or various chemical compounds. A distinction can be made between faecal sludge and wastewater sludge. Faecal sludge comes from on-site sanitation technologies, i.e. it has not been transported through a sewer. It can be raw or partially digested, a slurry or semisolid, and results from the collection and storage/treatment of excreta or blackwater, with or without greywater. Wastewater sludge (also referred to as sewage sludge) originates from sewer-based wastewater collection and (semi-)centralised treatment processes. The sludge composition will determine the type of treatment that is required and the end-use possibilities.Describes technologies for on-site collection, storage, and sometimes (pre-) treatment of the products generated at the user interface. The treatment provided by these technologies is often a function of storage and is usually passive (i.e. requires no energy input), except a few emerging technologies where additives are needed. Thus, products that are ‘treated’ by these technologies often require subsequent treatment before use and/or disposal. In the technology overview graphic, this functional group is subdivided into the two subgroups: “Collection/Storage” and “(Pre-)Treatment”. This allows a further classification for each of the listed technologies with regard to their function: collection and storage, (pre-) treatment only or both.Refers to the methods through which products are returned to the environment, either as useful resources or reduced-risk materials. Some products can also be cycled back into a system (e.g. by using treated greywater for flushing).A functional group is a grouping of technologies that have similar functions. The compendium proposes five different functional groups from which technologies can be chosen to build a sanitation system:
User interface (U), Collection and Storage/Treatment (S), Conveyance (C), (Semi-) Centralised Treatment (T), Use and/or Disposal (U).
A sanitation system is a multi-step process in which sanitation products such as human excreta and wastewater are managed from the point of generation to the point of use or ultimate disposal. It is a context-specific series of technologies and services for the management of these sanitation products, i.e. for their collection, containment, transport, treatment, transformation, use or disposal. A sanitation system comprises functional groups of technologies that can be selected according to context. By selecting technologies from each applicable functional group, considering the incoming and outgoing products, and the suitability of the technologies in a particular context, a logical, modular sanitation system can be designed. A sanitation system also includes the management and operation and maintenance (O & M) required to ensure that the system functions safely and sustainably. Funds spent for the acquisition of a fixed asset, such as sanitation infrastructure.
The utilisation of products derived from a sanitation system.
A sanitation system in which excreta and wastewater are collected and stored or treated on the plot where they are generated.
The means of safely collecting and hygienically disposing of excreta and liquid
wastes for the protection of public health and the preservation of the quality of public water bodies and, more generally, of the environment.

Waste matter that is transported through the sewer.
An open channel or closed pipe used to convey sewage. See C.3 and C.4
Used water from any combination of domestic, industrial, commercial or agricultural activities, surface runoff/stormwater, and any sewer inflow/infiltration.

Social Considerations

The Sedimentation and Thickening Pond may cause a nuisance for nearby residents due to bad odours and the presence of flies. It should be located away from residential areas.

Fact Sheet Overview

Input Products

Sludge

Output Products

Effluent
Sludge

Emergency Phase

Stabilisation +
Recovery + +

Challenging Ground Conditions

Suitable

Application Level / Scale

Neighbourhood +
City + +

Water-based and Dry Technologies

Water-Based

Management Level

Public + +

Technical Complexity

Space Required

Objectives & Key Features

• Solid/liquid separation of faecal sludge
• Sludge stabilisation

Strength & Weakness

  • The thickened sludge is easier to further treat, to handle and less prone to splashing and spraying
  • Can be built and repaired with locally available materials
  • No electrical energy is required if there is no pump
  • Odours and flies are normally noticeable
  • Long storage times
  • Important mechanical means and know-how needed for sludge management
  • Effluent and sludge require further treatment
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