Abbreviation: DANIDA
Glossary
a | b | c | d | e | f | g | h | i | j | k | l | m | n | o | p | q | r | s | t | u | v | w | x | y | z | 0 | 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9
- Danish International Development Agency (DANIDA)
- DANIDA is part of the Ministry of Foreign Affairs of Denmark Synonyms: DANIDA
- Decentralisation
- Decentralisation describes the transfer of central government powers, competences and resources to the local government, closer to the people and/citizen. The concept can also be applied to infrastructures (e.g. decentralised wastewater treatments). Synonyms: Decentralization
- Decentralised Treatment System
- Decentralised Treatment System Synonyms: DTS
- Decentralised Wastewater Treatment System
- Decentralised wastewater treatment systems or DEWATS are on-site wastewater treatment systems that have been mainly promoted by the Bremen Overseas Research and Development Association (BORDA). They generally consist of a series of four treatment units: sedimentation and floatation (e.g. in septic tanks or biogas settlers); an anaerobic treatment (e.g. in upflow baffled reactors or anaerobic filters); an aerobic treatment (in sub-surface flow constructed wetlands or unplanted sand- or gravel filters); and a final treatment (aerobic) in polishing/maturation ponds. The systems can be designed for both industrial and domestic wastewaters and from 1 to 1000 m3 per day. Synonyms: DEWATS
- Decentralised Water Supply
- Decentralised supply systems offer the possibility to provide safe drinking water where centralised supply systems are not feasible for economic or political reasons (e.g. in rural communities or informal settlements). Decentralised water supply refers to the small-scale purification and distribution o water. The decentralised treatment systems fall into three main categories: point-of-use systems (POU), point-of-entry systems (POE), and small-scale systems (SSS). POU and POE systems are designed for individual households while SSS can provide for community water supply, for emergency water supply in camps, or to purify water for sale in water kiosks. The choice of decentralised supply system depends on the local context and includes such factors as ease of use, maintenance needs, dependence on other utilities (e.g. electricity, fuel supply), and cost. Synonyms: Decentralised Water Supply
- Decentralized Treatment System
- Decentralized Treatment System Synonyms: DTS
- Deciding with the Community
- Deciding with the community presents various approaches and tools that facilitate participatory decision making.
- Decision Making Tools
- Decision making tools are approaches to take mutually-accepted decisions that benefit as many stakeholders as possible.
- Decomposition
- Decomposition is the transformation of dead organic material (plants, animals, etc.) into more basic compounds and elements by biological and biochemical reactions. Synonyms: Decay
- Deep dug well
- Deep dug wells are dug wells over 20 metres in depth, thus, unlikely to get contaminated but costly to construct.
- Deep Shaft
- Deep shafts are enhanced biological wastewater treatment systems. They are based on the process of activated sludge systems but particularly adapted where land is in short supply. Oxygen is injected into a return sewage stream, which is injected into the base of a deep columnar tank buried in the ground. As the sewage rises the oxygen forced into solution by the pressure at the base of the shaft breaks out as molecular oxygen providing a highly efficient source of oxygen for the microorganisms contained in the activated sludge. The rising oxygen and injected return sludge provide the physical mechanism for mixing. Mixed sludge and wastewater is decanted at the surface, the sludge is again enriched in oxygen while the supernatant continuously flows out of the system. The efficiency of deep shaft treatment can be high but they require high skilled labour for both, construction and operation and maintenance and large amount of energy.
- Deep Well
- A deep well is a hand-dug water well ranging more than 7m in depth and about 1.5m in diameter.
- Definition of Boundaries
- Setting clear boundaries is an important step in the development of any project. It makes it possible to stay focused on a specific area.
- Dehydration of Faeces
- Dehydration by adding dry organic material (e.g. in UDDTs) and long-term storage at high ambient temperature is the simplest treatment in order to transform faeces into a product that is safe for reuse or disposal. Dehydration can take place either on-site in a dehydration vault (e.g. double-vault UDDTs) or be done off-site in dehydration beds or bags protected from humidity. Simple storage at ambient conditions (temperature, pH and moisture) can require several years for pathogens to die-off. Increase of temperature, pH (alkaline treatment) and minimisation of the moisture content can significantly accelerate the process. Clever design and ventilation will increase temperature and decrease moisture content thereby enhancing the drying process. The addition of lime, ash or sawdust will raise pH (addition of lime and ash) and absorb humidity (sawdust).
- Demand Creation
- Creating demand is essential to achieve that newly developed approaches and technologies actually come in to use.
- Demand Creation Introduction
- Creating demand is essential to achieve that newly developed approaches and technologies actually come in to use. Synonyms: Demand Creation, Demand Creation Tools
- Denitrification
- Denitrification is a microbiological process in which nitrates and nitrities are reduced to nitrogen gas (N2), which is released to the air. Denitrification is an anaerobic process carried out by heterotrophic bacteria, this means that the bacteria need also organic material in order to complete the reaction: 5CH2O + 4NO3- + 4H+ -> 2N2 + 5CO2 + 7H2O.
- Denitrifying Ammonium Oxidation
- This is the coupling of denitrification and Anammox processes in one single reactor. Synonyms: DEAMOX
Abbreviation: DEAMOX
References:
Study on One-Stage Partial Nitritation-Anammox Process in Moving Bed Biofilm Reactors: A Sustainable Nitrogen Removal
- Deoxyribonucleic Acid
- DNA is a nucleic acid present in nearly all living organisms as the main constituent of chromosomes. It is self-replicating and contains the genetic instructions used in the development and functioning of the cells. Synonyms: DNA
- Department for Housing and Infrastructure Development
- Department for Housing and Infrastructure Development Synonyms: DHID
- Department for International Development
- Department for International Development Synonyms: DFID
- Department for Water Affairs
- Department for Water Affairs Synonyms: DWA
- Department of Infrastructure and Support Services
- Department of Infrastructure and Support Services Synonyms: DISS
- Desludging
- Desludging is the process of removing sludge from a tank, pit, or other storage unit.
- Detailed Project Report
- Detailed Project Report Synonyms: DPR, DPRs
- Deutsche Gesellschaft für Internationale Zusammenarbeit GmbH
- Deutsche Gesellschaft für Technische Zusammenarbeit (GTZ) GmbH changed its name to The Deutsche Gesellschaft für Internationale Zusammenarbeit (GIZ) GmbH on 1 January 2011. Synonyms: GIZ, GTZ
- Diammonium Phosphate
- Diammonium Phosphate (DAP) is a common fertiliser with the chemical formula (NH4)2HPO4. Synonyms: DAP
- Diarrhoea
- Diarrhoea is the passage of loose or liquid stools more frequently than is normal for the individual. It is primarily a symptom of gastrointestinal infection. Depending on the type of infection, the diarrhoea may be watery (for example in cholera) or passed with blood (in dysentery, for example). Diarrhoea is caused by a variety of microorganisms including viruses, bacteria and protozoan.
- Diesel Generator
- Consists of both a diesel engine (converts chemical energy to mechanical energy) and a generator (converts mechanical energy to electrical energy).
- Digestate
- Digestate is the sludge which remains after an organic waste (e.g. excreta, animal manure, kitchen, garden and market waste) has been anaerobically degraded and transformed into biogas by microorganisms via a process called anaerobic digestion.
- Dioxins
- Dioxins are a class of chemical contaminants that are formed during combustion processes such as waste incineration, forest fires, and backyard trash burning, as well as during some industrial processes such as paper pulp bleaching and herbicide manufacturing. The most toxic chemical in the class is 2,3,7,8-tetrachlorodibenzo-para-dioxin (TCDD). The highest environmental concentrations of dioxin are usually found in soil and sediment, with much lower levels found in air and water. Humans are primarily exposed to dioxins by eating food contaminated by these chemicals. Synonyms: Dioxin, PCDD, PCDDs, PCDD’s
- Direct Surface Groundwater Recharge
- In direct groundwater recharge water moves from storage above-ground (e.g. a spreading basin or ditch) to the aquifer via soil percolation. Most of the existing large-scale artificial recharge schemes in Western countries make use of this technique. In general direct surface recharge systems based on percolation have relatively low construction costs and are easy to operate and maintain.
- Disinfection By-product
- The use of chemical disinfectants in water treatment usually results in the formation of chemical by-products, some of which are potentially hazardous. If chlorination is practised, the trihalomethanes, of which chloroform is the major component, are likely to be the main disinfection by-products, together with the chlorinated acetic acids in some instances. However, the risks to health from these by-products are extremely small in comparison with the risks associated with inadequate disinfection, and it is important that disinfection should not be compromised in attempting to control such by-products. Synonyms: CDBP, CDBPs
- Dissolved Oxygen
- The concentration of oxygen dissolved in water, expressed in mg/l or as percent saturation, where saturation is the maximum amount of oxygen that can theoretically be dissolved in water at a given altitude and temperature.
- Dissolved Oxygen
- The dissolved oxygen (DO) is oxygen that is dissolved in water. The oxygen dissolves by diffusion from the surrounding air; aeration of water that has tumbled over falls and rapids. Synonyms: Dissolved O2
- Distributed Energy Resource
- Distributed energy resource (DER) systems are small-scale power generation technologies (typically in the range of 3 kWe to 10000 kWe) used to provide an alternative to or an enhancement of the traditional electric power system. Synonyms: DER
- District Water, Sanitation and Health Education Committees
- District Water, Sanitation and Health Education Committees Synonyms: D-WASHE, D-WASHEC
- Double Entry Accrual Accounting System
- Double Entry Accrual Accounting System Synonyms: DEAAS
- Double Pit Latrine
- Double pit latrines are latrines with several pits used in alternation. By constructing twin pits, it is possible to dig out a filled pit only after it has stood for a while (approximately one year) allowing the faecal matter to degrade while the other pit is put in use. Thus smell and the health risk during excavation will be reduced. Synonyms: Twin-pit Latrine, Twin-pit Toilet
- Drilled Well
- Drilled Well Synonyms: Borehole, Tubewell
- Drilling Fluid
- The addition of particular substances, e.g. natural clay, bentonite, organic polymers, air, foam, fibres, fresh cow-dung, to drilling water increases viscosity and hence improves removal of cuttings and stabilises the borehole.
- Drinking Water
- Freshwater that is chemically and biologically safe for human consumption, naturally or by purification. Synonyms: Potable Water
- Drip Irrigation
- In drip irrigation, water flows through a filter into special drip pipes, with emitters located at different spacing. Water is discharged through the emitters directly into the soil near the plants through a special slow-release device. If properly designed, installed, and managed, drip irrigation may help achieve water conservation by reducing evaporation and deep drainage as compared to other types of irrigation such as flood or overhead sprinklers since water can be more precisely applied to the plant roots.
- Dry Digestion
- Low-rate anaerobic digestion systems are classified according to the percentage of total solids (TS) in the waste stream. Dry digestion means that the TS content is higher than 20 %. Synonyms: High-solids Digestion
- Drying Bed
- Drying beds are either planted or unplanted sealed shallow ponds filled with several drainage layers and designed for the separation of the solid from the liquid fraction of (faecal) sludge from latrines, septic tanks, biogas reactors, trickling filters, etc. Sludge is dried naturally by a combination of percolation and evaporation. When plants are present, evaporation is enhanced by transpiration (evapotranspiration). The percolate still contains pathogens and needs to be collected for treatment or controlled reuse. After treatment in planted drying beds (humification beds), the dried sludge, a nutrient-rich soil amendment, can be directly used in agriculture. If unplanted sludge drying beds are used, additional treatment by composting may be foreseen. Unplanted drying beds need to be desludged before fresh sludge is applied, while humification beds can be filled up intermittently requiring desludging only once ever 5 to 10 years. Drying beds are relatively easy to construct and simple to maintain, although large surface areas and man- or mechanical power is required for regular desludging.
- Dual Flush Toilet
- A dual-flush toilet is a variation of the flush toilet designed to save water by using two buttons or handles to flush different levels of water.
d