Greenhouse Solar Dryers: A Cost-Effective Solution to Ensure Safe Application of Faecal Sludge in Agriculture

Non-judicious and long-term application of chemical fertilizers not only deteriorate soil quality but also contributes to climate change effects due to the emission of greenhouse gases during the production and application of these fertilizers. On the other hand, there is an urgent need to look for alternative nutrient sources for food production to feed the growing population.

It is widely known that human excreta is rich in nutrients, specifically Nitrogen and Phosphorous. With the recent thrust on faecal sludge treatment and safely managed sanitation, there is an opportunity to use human excreta as a nutrient source. However, there are concerns of health risks due to the presence of pathogens in faeces. The main cause of concern is the soil-transmitted helminth infections as these are highly resistant to treatment and viable for several years.

In this context, this study was conducted in 4 locations (FSTPs – Faecal sludge treatment plants) of India – Angul, Dhenkanal, Karunguzhi and Devanahalli with the main objective to evaluate the efficiency of polycarbonate-based greenhouse solar dryers in reducing the Helminths eggs in the final treated sludges. Greenhouse solar dryers (GHSD) use passive drying to help increase the temperature and decrease humidity to ensure pathogen kill as well as faster drying.

Scenarios studied under the project:

Following were the assumptions made for the study,

  • Increased temperature and decreased relative humidity inside the GHSD chamber will help in reducing the sludge drying time.
  • Longer exposure of sludge to higher temperature (>50°C) will inactivate Helminths eggs.

GHSD is the polycarbonate sheet installed over the drying beds. This has a parabolic shape to resist wind and to induce greenhouse effect inside the drier. This greenhouse effect inside the drying chamber helps removing the moisture laden air and the moisture content from the drying product (Figure 2).

Solar pasteurisation unit (SPU) follows the same working principle and the structure of the GHSD. However, the height of the roof is less compared to the GHSD. The dried sludge from the GHSD is placed in the SPU. Due to reduced height of the chamber and low moisture content of the sludge, SPU can reach to a higher temperature of more than 60 degrees Celsius which will help eliminating the pathogens (Figure 3).

Galvanised (GI) sheet is one of the most used roofing materials over the sludge drying beds. These are galvanized metals made of thin sheets, coated with zinc. The main purpose of these sheets is to protect the drying beds from getting wet during rainy season.

Below mentioned scenarios were studied under the project,

  • Greenhouse solar dryer (GHSD): Angul and Devanahalli FSTP
  • Galvanised (GI) sheet + Solar Pasteurisation Unit (SPU): Dhenkanal FSTP
  • GI sheet and GHSD: Karunguzhi FSTP.

Assessment of Operational Status of Fecal Sludge Treatment Plants

The demand for safely managed sanitation services is increasing with the rise of the global population. The declaration of open defecation-free (ODF) in 2019 has ensured access to toilets to all in Nepal but increased the challenge of safe management of generated sludge from these toilets. Ten Faecal sludge treatment plants (FSTP) have been established by 2022 but studies on their operational status are limited. This paper aims to present the operational status and implication of social, financial, technical and managerial aspects on the operational good/poor status of seven FSTPs in Nepal. The study was conducted through literature review, deskwork, key informant interview (KII), multi-stakeholder consultation meeting (MSCM),   field observation  and data analysis. The study was conducted in 6 operational FSTPs; Lubhu, Gulariya, Charali, Kakarbhitta, Waling and Birendranagar, and one established but not operational FSTP; Madhuwan. The FSTPs were accessed on 7 indicators in total considering social, managerial, technical and financial aspects. None of these FSTPS was in good operation in all aspects. However, Gulariya and Waling FSTP were in the satisfactory condition given the treatment quality meets the standards protecting the public health of locals. To conclude, FSTPs in Nepal are still facing challenges in operating in good condition.

Replication Potential of the Uhuru Park Pilot Project from Kenyan Perspective

The city of Nairobi in Kenya has a population of about 5 million people within the city itself, but the population is estimated to be about 10.8 million within the metropolitan area. The city is grappling with the issue of water, as the current production is about 500 000m3/day, against a demand of 800,000m3/day. Heavy infrastructure and capital are required to be able to bridge this Gap. A strategy that would help in reducing this gap would be most welcome. Sewerage coverage is estimated at about 50%, leaving about 50% to depend on on-site sanitation like septic tank and using exhausters and pit latrines in extreme cases. A method that would enable to bring up a decentralized wastewater treatment plant that do not require heavy infrastructure like sewer networks is most welcome.

The city also has great challenges in the collection of wastewater and fecal sludge because of the fast-growing population due to rural-urban migration, which has accelerated the population growth. Rivers in the city are heavily polluted because of the overflow from the current sewer networks and the discharges from areas like focus settlement that are not connected. The open channel that was visible at Uhuru Park was initially meant to convey storm water but is currently used to conveying storm water melt with sewage from the overflow from diverse areas and institutions.

Currency in Nairobi, the most common wastewater treatment systems are stabilization ponds and aerated lagoon coupled with constructed wetlands as well as conventional treatment systems. But the main problem is that this requires huge infrastructure for collection of sewage and transporting it to a central point. So, the need for decentralized systems is key.

The photo on Page 4 (See attachment) is one of the rivers in Nairobi which is flowing next to an informal settlement; this picture presents the heavy pollution in the river and the environment. This has surely helped the Government to come up with the Nairobi River Rehabilitation Commission to try and clean up these rivers so that the water can be available for other uses. The system being discussed actually falls into that category of helping to clean the rivers. The initiative to have this decentralized system in Uhuru Park was initiated at a very high level, when the President of Estonia visited Kenya, and had discussions with her host President of Kenya on areas of bilateral cooperation. One of the results was that Estonia being fairly advanced in terms of technologies, especially in water and wastewater treatment, could assist Kenya in coming up with very innovative ways of treating wastewater, and that is how the Spacedrip device was booted. The Estonia President nominated the Spacedrip team which was accompanying her to do a pilot in Nairobi, and the Kenyan Government nominated the Nairobi Metropolitan services and the Executive Office of the President to work on the pilot. It was deemed appropriate to pilot this system in a very central place, where it can be accessed by other leaders and institutions from around the country. And that’s how the pilot was positioned in Uhuru Park (See Attachment, Photo in Page 7), one of the main recreation parks located within the Central Business District (CBD) in Nairobi. Anybody coming for recreation within the park can see it. The map (See attachment, Page 6) presents in light green the Uhuru Park, which is a very centrally placed within Nairobi CBD with the major governmental institutions located in close proximity including even the Parliament, the President’s Office, the city hall, major hotels and other business premises.

Uhuru Park was chosen for this pilot because before the installation of this system, potable water was used to irrigate the Park, which is a huge area of over 50ha, with the corresponding pressure on potable water. Indeed, the city is already experiencing a deficit of 300 000, and instead of saving on the water, the same water is used for irrigating the park. So, the idea of putting this system in the Uhuru Park was to make sure that the effluent treated from the system would be used to irrigate the park, and by so doing help in reducing the pressure on demand on the drinking water.

Aqua Consult Baltic designed the technology enabling to connect with the irrigation infrastructure of the Uhuru Park, and there has been a partnership on the consultation during the commissioning and six-months operation of the plant handed over to Nairobi Water Sewage Corporation (NSWC). Ruji Africa was the local partner of Spacedrip helping in the preparation, installation and piloting the automated wastewater treatment and reuse system. We have already obtained an update on environmental impact assessment from a Regulator, which is the National Environment Management Authority.

One of the key benefits of this water reuse system is that it requires a very small space, and the container system can be installed inside a building or smaller areas, unlike the other systems which require huge plots of land (land in a city like Nairobi is very scarce to get). This is therefore a solution to areas that do not have land. The efficiency of the system lies in the total pathogenic removal for key area, because the effluent can then be used for other uses like irrigation. In the future, effluents from this system could also be used in flushing of toilets and cleaning as the case maybe, since most of the water is used for cleaning services. For now, because of the stigma associated with the sewage water, it might be too early to start talking about using it for drinking. It already helps to reduce pressure on drinking water, and it is estimated that adopting this water reuse technology in most of the heavy consumers of water (like tourism, hospitality industries, informal settlements, commercial and residential buildings, food processing…) could help cut the demand for water by about 50%, and then the pressure on potable water could really come down.

One key input of this system is electricity because of both the automation and the pumping within the system. However, this can be addressed in future. Currently, the system also incorporates a partner’s solar system that produces part of the electricity, especially for automation and critical operations of the system. But in future, we think the solar energy should be made the main source of energy by incorporating more solar panels and batteries to store the energy.

Financially, this system gives an advantage, especially saving on heavy cost for the construction of the infrastructure required for centralizing the system. This is the main cost that applies for the sewerage system. With a decentralized technology and no need for heavy infrastructure, specific saving in the cost makes this system a big advantage.

The result of this piloting is supposed to inform and advise the policy makers and help them in the development of by-laws that would be required for some institutions. With the water consumption and discharge of given capacity, it should be of interest to install this water treatment and reuse system in the tourism and the hospitality industry, urban, commercial, building institutions, and the food processing industries. Doing so will also help the private sector participation accelerating the coverage in terms of sewerage and help those involved in the management and control of water demands. So, as an addition to constructing new infrastructure to bring in more water, we can manage the quantity we have better by treating our effluent and reusing it. This is already happening in buildings like the local university of Nairobi, which is harvesting all the water within the building that is then reused in flushing of toilets. This idea is not very far-fetched, and its time has come. Policy-makers need to be advised on that so as to come up with necessary bylaws to help manage the water demand distribution in the country.

Pilot Project for Wastewater Treatment and Reuse at Uhuru Park Nairobi

Aqua Consult Baltic was established in 1997 in Estonia, and the technology presented herein came into existence in Kenya thanks to a local company. This mother company located in Germany in Hanover, grew up from there. She implements projects around the world and mainly in Baltic States. This is an engineering and consulting company which mostly specializes on wastewater treatment and derivatives, secondary waste handling and municipal waste treatment plant. The company is currently working on a Slovenia and Vienna Project, which is 550 000PE and also in Tallinn, Estonia for 400 000 equivalents. Given that industrial municipal waste is difficult to predict, it is important to know its boundaries and behavior; so, for this type of waste, there is need to do a lot of modeling which includes fractionation of the wastewater and doing the piloting before providing the engineered solution to the customer. The company deals with oil and gas industry, chemical foods, agriculture, industrial plant, and projects linked to water reuse systems. Currently, the Tallinn water treatment of 400,000 equivalents transforms the surface water into potable water, using new technologies that are developed. The company has built good relations with universities, where testing and research are carried out.

Besides, Spacedrip – also an Estonian company – is an innovative and young company that focuses on water treatment systems which reuse water in a small scale of 25 to top 2000 people for water companies, real estate developers and defense sector. The defense sector for example has mobile units in different places that need to be supplied with water. Spacedrip thus provides them with showering or toilet systems that reuse water continuously.

Relationship between Aqua Consult Baltic and Spacedrip Group

A few years ago, Aqua Consult informed Spacedrip of the design of a new model of houses prefabricated in the factory and deployed to the sites. However, there is occasionally no infrastructure on the site, neither a wastewater nor a drinking water system. They needed a machine which was able to transform wastewater into drinking water. Spacedrip made the design, which is now used in Aqua Consult Baltic factory and the latter developed it further to what it has become today. It is now a more reliable product that can be fully put on automation, a very nice product. This device was funded by the Government of Estonia as a technology to be exported in other countries, and whose added value is the environment-friendly feature and saving the greenhouse potential.

During the funding, the Estonia President at that time visited Kenya. He knew about the existence of this company making wastewater into drinking water; indeed, there is less than 1 million people or so in Estonia, and everybody know each other. He told his peer, the President of Kenya of this technology, and the latter showed interested, hence the relationship with partners on site and the launch of this Kenya project.

Problem Statement

As President William Ruto put it: “Kenya Government has resolved to not only reclaim Nairobi’s reputation as Africa’s green city but also live up to its ancestral identity as the river of cool and fresh water”. The Kenya project emerged from findings below:

  • The river that flows in Nairobi is polluted enough and needs to be cleaned to get the same quality as before the settlements. So, there are a lot of projects ongoing to make this river cleaner and for a better environment.
  • Secondly, Nairobi City water production is around 500 000 m3/day, but the amount needed to meet existing demand is 800 000m3; there is a lack of green water to use.
  • Furthermore, there is lot of drinking water used for some needs that technically safe recycled water could have met (flushing toilets, irrigation, etc.) Indeed, water reuse systems can reduce the water demand by 50% (800 000m3/day is necessary. If 50% of water are saved, then only 400 000m3 will be needed). To implement this project, infrastructure upgrade is not necessary.

A pilot plant was thus installed at Uhuru Park, Nairobi for two purposes:

  1. clean up the Nairobi river a little bit, and
  2. help reuse water.

The Solution Implemented

The Spacedrip device (see page 7 in attachment) is a container treatment plant that takes up the wastewater from a channel that flows through the Uhuru Park, Nairobi up to 50 m3/day and cleans it up so it can be reused for irrigation of the park. The system is handled with an automation software so it can be monitored and run up from a far distance and keeps a working order in every cases. This technology is not new per say, but it has a sedimentation tank in front of it. There is a biological part where organics and a bit of nitrogen are removed; then, a filtration unit that micro- filtrates out most of the bacteria; clean water enters a tank in a technical chamber and from there, it is filtrated by UV light and chlorine when necessary. So, water comes into the treatment plant from the stormwater drain channel and goes out the treatment plant through sprinklers in the park. Water arrives through a storm water channel. There are quite no rainy events there, but a lot of water coming from septic tanks and industrial site discharge, which is unknown and difficult to predict. This means that water flowing through is quite dirty, and direct use for the irrigation is not a good idea. However, following treatment, it becomes very clean from organics and bacteria. This technology has been used at the Uhuru Park for two weeks now.

Results Obtained

The commissioning went well a month ago (May 2023), and the system has been running in its full capacity for two weeks now. Currently, up to 25% of the necessary Uhuru Park irrigation water is coming from this treated wastewater device. The implementation of this device aimed to give a proof that this kind of system with sound automated plug and play technology works well. These compact units can be placed anywhere, even in small areas. It can run for a long period of time and is in a testing phase. The input and outputs analyze results are presented in Chart 2 (See Page 9 in attachment), with a 100% bacterial removal thanks to this technology. The influent and output picture shows the water obtained is quite pure. However, it is not safe enough to be consumed and is only for irrigation purposes.


This kind of system is same with Seehausen (Germany) water reuse systems. But this is a smaller unit that is quite compact, and which can be placed in small areas or bigger city centers where the wastewater is reduced. The water obtained can be used for toilet flushing or garden irrigation and there is no need for building new infrastructure to use it. Thanks to the IT Solution enabling the distance monitoring, there is no need to go on site for maintenance.

Therefore, it is possible to predict the maintenance of the system, that will allow it to run for a long time and avoid breakdowns. Pictures of some small three-meters containers are presented in Page 10 (See attachment); these are devices with showering and toilet units that were produced by Spacedrip for military projects, and which can be placed anywhere for continuous reuse of water.

Commercialization of Wastewater Sludge Beneficiation

Sewage sludge disposal has become a costly and environmentally challenging matter that requires an innovative approach. Agriman (Pty) Ltd is a South African based company with an international footprint that provides a complete value chain solution for the handling, processing and beneficiation of wastewater sludge to a commercially marketable fertilizer.

Depending on existing infrastructure and processes employed at a wastewater treatment works (WWTW), Agriman has developed the ability to migrate upstream in the process line to perform and manage critical functions related to the digesters and dewatering of sludge that have a direct effect on sludge quality. By means of accelerated solar drying, sludge is dried and stabilized before disinfection and granulation takes place. Once granulated the product is then blended with conventional fertilizer feedstock to customer requirements for agricultural use, effectively transforming a hazardous waste into a registered organic fertilizer that is safe for agricultural use.

The environmental, economic and socio-economic impact of the traditional disposal methods of wastewater treatment works’ sludge is not a sustainable solution. Authorities are also being pressured by laws and legislations that are phasing out the disposal of sludge at landfill sites. Provided that dewatered sludge can be dried cost effectively at a specific WWTW,  Agriman can provide a sustainable long-term alternative that can be implemented on a large scale to safely handle and process sludge to an organic based fertilizer. The trend towards sustainable farming practices creates a high demand for commercially available organic fertilizers to supplement chemical fertilizers. This demand is currently not being met.  The potential to commercially beneficiate wastewater sludge to a registered and approved agricultural fertilizer on a global scale has been shown by Agriman as a model that is economically viable for wastewater authorities, the agricultural industry and sustainable development.

Bisol Systems for Waste Water Management

Bisol is a company started by a team of young civil engineers, and environmental enthusiasts, who are passionate about solving sewer problems and improving water sustainability. Their products are engineered and custom made to manage sewage and also recycle the sewage back to water for sanitary needs in short non-portable water that will be used for flushing toilets, cleaning the compounds, irrigation of the lawns, and farm irrigation.

The company works with institutions, private owners, and commercial businesses to promote wastewater recycling. The prospects is to be able to reach a large magnitude so that the company can improve sanitation in the region and water security.

Some of its products such as bio-toilets improve sanitation in schools and promote stability. There are also ultra-modern biodigesters that reduce and completely stop pollution, and a compact sewage recycling system that recycles sewage, treats and recycles water from the septic or biodigester and turns it into clean clear water.

Some of the systems presented in the attachment are Bisol’s own innovations and modifications. The company thus proposes custom- made solutions for different setups, through wastewater management consultancy team.

Underground Sewerage Schemes: Last Mile Connectivity

To keep up with the demands of rapid urbanisation, the Government of Tamil Nadu (GoTN) has accorded priority to implement Under Ground Sewerage Schemes (UGSS) in all the needy Urban Local Bodies (ULBs) through different financial schemes in a phased manner. The GoTN has made efforts to reach the ‘last mile’ with adequate and equitable sanitation and hygiene in ULBs of Tamil Nadu.  This paper aims to draw insights into the underlying factors and initiatives taken by the GoTN for the UGSS last-mile connectivity in the state.

Indeed, in a state like Tamil Nadu (TN), sanitation is essential for enhancing the quality of life and health and improving productivity. In this regard, GoTN has taken initiatives in UGSS implementation and also in Fecal Sludge Management (FSM) in a phased manner to reach last mile, which are broken down into three stages detailed in the full article attached herein: i) from 2000 to 2008; ii) from 2008 to 2017; iii) from 2018 to present.

Apart from the financial support initiatives to the households, dedicated Information, education and communication (IEC) programmes were also conducted in different parts of the state to educate the households on taking the service connections to avoid direct disposal of wastewater to the stormwater drains or the neighbouring lands.

For the ULBs which are not covered under the UGSS implementation scheme, a separate plan had been prepared on FSM for safely managed sanitation in the state. The timeline of legal and regulatory framework associated with FSM initiatives are given in the full article attached herein.

The use of water supply and sewerage connection deposits, interest-free loans, and taxes in Tamil Nadu suggests that long-term sustainability of sewerage systems can be achieved with policy commitment, effective project appraisals and citizen involvement. The efforts by GoTN on UGSS last-mile connectivity can be taken as a reference by other states to improve the last mile with inclusive sanitation. The major lesson learned from the UGSS implementation is that the selection of towns for the implementation has to be based more on public demand, their capacity to pay back the loan amount, and the financial capability of the ULB than on the readiness of the DPR for the project.

A Monitoring Technique of Desludging and Decanting Faecal Sludge

Tamil Nadu is a rapidly urbanising state that has been establishing and scaling up sustainable FSSM, leading the way in innovating technologies and operating models in sanitation. Safe collection, handling, and transport of fecal sludge (FS) is an integral part of a septage management programme. This paper documents the use of load axle sensors with GPS technology in the de-sludging vehicle to understand the movement of the vehicle, de-sludging and disposal locations, travel distance and time, and the time for de-sludging and decanting. These learnings help determine the location of current disposal, service area, and planning of decanting facilities.

 As a matter of fact, de-sludging vehicles collect and transport septage to designated decanting facilities, eliminating the need for manual emptying and reducing the risk of human contact with FS. As per the Tamil Nadu Urban Local Bodies (Amendment) Act (2022), the desludging vehicle must install a GPS device to monitor the de-sludging and decanting activities.

However, GPS can only track the movement of the vehicle and not locate de-sludge locations and whether operators were safely decanting the FS at the designated spot. Identification of the desludging and decanting locations with loaded quantities using GPS technology is difficult and a highly time-consuming process. The time required to analyse each vehicle could be a challenge for the ULBs as they scale this monitoring strategy.

Therefore, a study done on this aspect by the Tamil Nadu Urban Sanitation Support Programme (TNUSSP), intended to identify the possibilities of monitoring the de-sludging vehicles using a load sensor with GPS technology.

This monitoring helps identify the service area of the vehicle, the desludging and decanting locations, quantity of FS collected, travel time and distance between desludging and decanting locations, and time for desludging and decanting.  The analysis of travel distance and time aids for planning additional decanting facilities. Additionally, the vehicle was discovered to be loaded overnight and parked, so it is advised to keep the decanting station open at night as well.

Field teams are working on upgrading the system with an ultrasonic load sensor for more accuracy at an affordable cost.  Also, the option of incorporating the sensor output with the FSSM application to plan schedule de-sludging, auto deduction of decanting fee and real-time plant utilization rate, etc., are under progress.

The major challenges associated with scaling this monitoring technique are as follows.

  1. Requirement of an efficient monitoring system within the ULB
  2. Highly priced system: Possibility of vehicle owners with more number of vehicles refusing to adopt
  3. Lower acceptance among de-sludging operators for installation fearing regular monitoring of their activities
  4. Possibility of vehicle operators tampering with device
  5. Difficulty in orientation for desludging operators about proper desludging and decanting due to frequent changes in personnel.

Download the full article to read more.

Share Water No. 13

The thirteenth issue of the African Water Association (AfWA) technical and bilingual magazine, Share Water, is now available. It provides solutions in terms of guidelines and tools likely to help manage the WASH businesses efficiently and mitigate the shortage of water supply, for improved access to sustainable water and sanitation services for all in Africa.

Among these solutions, the water safety plan (WSP) approach is widely recognized as the most reliable and effective way to consistently manage drinking-water supplies to safeguard public health. Since the introduction of WSPs in the third edition of the WHO Guidelines for Drinking water Quality (GDWQ) and the International Water Association (IWA) Bonn Charter for Safe Drinking Water in 2004, a significant number of water suppliers have implemented WSPs, and many governments are actively promoting their implementation and/or inclusion in national legislation.

Some benefits of WSP implementation include the promotion of public health by continuously assuring safer drinking-water for consumers, the setting up of a proactive (rather than reactive) framework for managing drinking water quality, the early identification of new/increased risks-incidents, the in-depth systematic evaluation of water systems, and much more…


Zoom : des équipements pour l’approvisionnement en eau et le traitement des eaux usées

Les solutions du groupe AVK interviennent à ce jour dans tout le processus de l’eau ou cycle de l’eau, du pompage au traitement, en passant par le réseau de transfert, de distribution et de traitement des eaux usées. Les équipements fabriqués et commercialisés rentrent dans la gamme des vannes à opercule (jusqu’à 2500 de diamètre), vannes à papillons (jusqu’à 3600 de diamètre) et vannes de régulation ou intelligentes, qui permettent de stabiliser une pression ou un débit en fonction de la consommation des abonnés. Ces vannes permettent de suivre le débit journalier et le débit nocturne, pour ne pas rester sur une pression en aval de 4 à 5 barres sur toute l’année alors que le tirage est à forte consommation. Des vannes de branchement avec système de clapet sont également disponibles, et l’entreprise dispose à ce jour d’une des gammes les plus larges de robinetterie et accessoires de canalisations pour l’eau potable ; toutefois, elle ne fabrique pas les pompes.

La vanne papillon est adaptée aux gros diamètres, pour une meilleure gestion de l’encombrement et du regard. Il existe une gamme dont les matériaux sont adaptés aux liquides agressifs ou eaux usées. Les vannes murales et guillotines sont quant à elles utilisées pour les stations d’épuration. La gamme de protection incendie pour sa part, devra être placée sur des poteaux incendie dans les villes afin d’assurer la sécurité des habitants.

La vanne opercule est la plus utilisée dans les réseaux d’eau en Afrique ; bien qu’assez banalisée car enterrée (l’appareil est souvent invisible), elle sert à sectoriser un réseau dans le cadre de la procédure pour déterminer l’Eau Non Facturée (ENF). Si la vanne n’est pas étanche, toute la logique de calcul est fausse. D’où la problématique de la qualité des produits installé sur les réseaux, car très souvent les vannes ne fonctionnent pas et ne sont pas étanches.

Le logiciel AVK Assist peut être installé sur I-pod ou Android pour lire les données des vannes connectées qui disposent d’un code-barres ; par ce moyen, il est possible de géolocaliser l’emplacement de la vanne. Il existe également des fiches techniques et des petits logiciels pour calculer les débits. La vanne intelligente comprend un système de capteurs qui donne à l’exploitant des informations sur la manipulation de la vanne de façon instantanée, et celle-ci ne peut plus être manipulée à l’insu de l’exploitant. Pareillement, cette technologie permet de signaler la manipulation du poteau incendie par une personne non autorisée. Cette technique innovante s’avère très utile pour lutter contre le phénomène de l’Eau Non Facturée, i.e. l’eau produite mais non facturée à l’abonné.

AVK impose sur le cycle de l’eau les exigences qu’elle s’est fixée pour la gestion du gaz. Il y’a un écrou de manœuvres complètement serti englobant dans l’opercule en fonte et entièrement vulcanisé. Il n’y a aucun mouvement, ni vibration entre l’écrou et l’opercule, donc aucune corrosion. Il existe un concept où l’écrou est simplement positionné et un mouvement continuel peut être noté. Aussi, après quelques mois ou quelques années, il y’a un phénomène de vibration et donc de corrosion.

AVK est l’une des seules sociétés qui fabrique le caoutchouc (polymère) utilisé pour ses équipements. Une vanne opercule c’est de l’EPDM compatible à l’eau potable. C’est dire que AVK possède la maîtrise qualitative du processus de fabrication, qui tient compte de la norme européenne EN 681, relative à l’élasticité du caoutchouc et la rémanence (capacité à pouvoir s’écraser quand on ferme la vanne et à retrouver sa forme initiale quand on ouvre la vanne). La certification allemande GSK permet à AVK de garantir la qualité du revêtement époxy sur la vanne. Il existe plusieurs critères de contrôles non destructifs qui permettent de garantir la longévité du revêtement époxy sur les équipements, ce qui empêche toute corrosion de la vanne, même après dix (10) ans d’utilisation. En tant que garantes de la qualité de leurs réseaux, les sociétés d’eau gagneraient à tenir compte de ces certifications.

Le concept de vannes à brides peut être multiplié en différents types de connexion. Même si la vanne opercule est le nouveau produit lancé, il existe plusieurs pipes en PEHD dans la sous-région. Il s’agit d’un équipement dont les 02 embouts sont très manchonnés, sans aucun boulon à serrer et sans couples de serrage à respecter ; il suffit de souder les tubes PEHD sur les embouts qui sont déjà sertis et testés en usine. L’avantage du PEHD est la garantie d’un niveau zéro de fuites, car le polymère peut être soudé.

Les bouches à clé vont de pair avec les vannes, car elles constituent le point d’accès de la vanne par lequel il est possible de faire de la recherche de fuites grâce aux logeurs, entre autres systèmes de qualité, qui permettent d’écouter le retour du réseau. À la suite des vols de fonte et à la demande des clients, AVK s’est orientée vers des matériaux composites qui sont recyclables, économiques, non corrosifs, ne peuvent pas être volés et consomment moins d’énergie afin de répondre aux exigences énergétiques actuelles. Une nouvelle bouche à clé en tête fonte, tout en composite (tête ronde, marquage hexagonal, couleur dédiée, numérotation, etc.), qui peut être réhaussée pour s’ajuster sous la chaussée au passage des véhicules a été lancée. En effet, l’un des problèmes récurrents est l’écrasement de la chaussée par les gros porteurs (véhicules à fort poids), qui laisse en saillance la bouche à clé ; elle reste donc en hauteur par rapport à la chaussée. La solution proposée va suivre le mouvement de la chaussée, et assurer une continuité constante entre la tête de la bouche à clé et la route, qui facilitera la manipulation de la vanne au cours des années à venir dans un souci de durabilité. À la demande des clients, elle est en cours de développement et de vente en Afrique.

L’origine de l’ENF peut être les fuites dans les vannes. Aussi, des équipements de réparation de conduite revêtent une importance majeure. Il s’agit des solutions ou manchons toute pression, tout matériau (pipe en PVC, PHP, acier, etc.) et tout type de pression (jusqu’à PN=40) qui permettent de réparer les canalisations ou conduites en charge sans couper l’eau. Les informations sur le type de conduite, le diamètre extérieur et la pression permettent de fabriquer des manchons dédiés pour résoudre rapidement et à faibles coûts les problèmes de fuites, évitant ainsi les coupures d’eau intempestives.

L’emboiture de deux (02) canalisations en PVC ou en fonte qui ont des fuites peut également être réparée. Les avantages comprennent la simplicité de la réparation qui est définitive et garantit l’étanchéité sur le long terme, sans coupure de tube, sans déterrer la canalisation et sans coupure d’eau afin de ne pas perturber les utilisateurs finaux lors du processus.