The second largest sanitation company in the world based on the number of customers in a single country, the São Paulo State Basic Sanitation Company (Sabesp) ranks right behind China’s Beijing Enterprises Water Group. The company, which supplies water to 363 municipalities in the state of São Paulo, a total of 27.9 million people, shifted its focus towards technology in 2009. The following year it established a Center for Research, Technological Development and Innovation with the objective of generating and prospecting technology for the company itself and for the sanitation sector as a whole. “There is a specific technological shortage in the field of sanitation. Today, many of the technologies we use were merely adapted for this area,” says civil engineer Cristina Zuffo, manager of the Sabesp Department of Technological Prospecting and Intellectual Property.
“Our idea is to develop new technologies and encourage suppliers to serve the sanitation sector with the products generated through this process,” says Zuffo. Until 2009, the company’s research and development (R&D) projects were unambitious, with no corporate infrastructure to support them. The initiatives were decentralized and ad hoc. The Sabesp Center was established with guidance from the University of Campinas (Unicamp) Department of Science and Technology Policy, in the Geosciences Institute, as part of a project coordinated by Professor Sérgio Salles. A survey of sanitation technology research in specialized journals and databases of scientific articles was also performed, in addition to discovering what companies in Brazil and around the world are doing in this field.
Even before the company’s technology center was ready, Sabesp signed a cooperation agreement with FAPESP to support research projects in the area of sanitation through the Partnership for Technological Innovation Program (PITE). The first call inviting researchers from São Paulo research institutions to submit projects was for funding of R$10 million, with R$5 million provided by Sapesp and R$5 million by the Foundation. Nine proposals were selected from among 49 submitted on the topics chosen by the company, such as sanitation economics, energy efficiency, and wastewater treatment. The projects chosen through a second call should be announced in the coming months, also for funding totaling R$10 million.
One of the project themes is to solve one of Sabesp’s major business challenges, namely how to decrease water loss, mainly due to cracks in the mains. In 2012, Sabesp failed to earn 25.7% more in revenue due to this problem. According to 2013 figures through November, 31.4% of water disappeared from the network based on the volume loss calculated by taking the difference between the measurements taken at the large meters installed at the exit of large distribution reservoirs and the small residential or commercial water meters at the end of the distribution network. The company estimates that 66% of losses were due mainly to leakage and the remaining 34% due to fraud, broken meters, and water provided as a social welfare measure. The loss rate reached 29.5% in 2007, but the company expects it to decrease to 13% by 2019, within international levels. Reducing losses is also is a way to reduce supply shortages during periods of drought, such as occurred in January 2014 in the São Paulo Metropolitan Region.
The detection of losses due to leaks could be better diagnosed, which would improve income and contribute to avoiding water shortages. To prevent the São Paulo Metropolitan Region from suffering this problem, this year the company will begin construction on a channel that will bring water from the Cachoeira do França reservoir, in the municipality of Ibiúna, 70 kilometers from the capital.
Traditionally, around the world, when a leak is suspected, perhaps due to the differences in volume of water leaving sector reservoirs and that received by customers, an employee goes to the location of the suspected leak with a geophone. The equipment consists of a sensor that, in contact with the ground, picks up vibrations in the soil and then transmits them to an amplifier and to headphones. A technician trained to use this equipment listens to the sounds captured from under the paving of a backyard or a street, for example, and if there is a noise that indicates a rupture or leak, a sanitation company team will go to the site, dig, and make the repair.
“When the water comes up to the surface, it is easier to identify the location, but if it is deeper, the water goes down into the water table. With the geophone, locating the leak depends on the skill of the operator, who needs to work with as little background noise as possible. That is why so many of these tests are done at night,” says Zuffo. But how can this task be improved, so that both searching for leaks and identifying the need for repairing them become more precise? Prof. Linilson Padovese, of the University of São Paulo Polytechnic School (Poli-USP) Mechanical Engineering Department, submitted a proposal to develop a software program that could help technicians and the company in this effort. A database of the signals characteristic of the problems in the distribution network, which are known to geophone operators, would be needed. “Since this database of recorded signals does not exist, because the available equipment is analog, we changed the focus of the project to first develop equipment to collect and digitally record signals,” says Padovese, who has had previous experience in acoustic vibration sensing in industrial machines and in applying signal processing methods to defect detection. “We decided to create a device that would allow digital recording and geo-referencing of the sounds heard by technicians. In this way the company will be able to put together a database of digital signals, all marked with GPS location data. Moreover, in order to lower equipment costs and make the technology simpler and easier to use, we decided to use smartphones as the geophone platform.”
Padovese notes that while technicians listen to filtered signals in the field, the digital recording is of the raw signal without any filtering. Thus signals can be studied and reprocessed by company technicians, off-line, using standard filters or other techniques for signal processing and pattern recognition to improve the diagnostic process. After the database is set up, automatic diagnosis software can be developed to increase the efficiency of the leak localization process in the Sabesp network.
“The ideal would be to reduce dependence on the evaluation by a single technician,” says Padovese. “To understand the company’s problems better, we talked to the technicians, and this helped us redirect the project. The researcher explains that a geophone-type sensor could not be developed within the scope of the current project. They use the geophone sensors that are available on the market. The hardware for analog signal conditioning and digitizing was developed during the project, as well as an app for the Apple iPhone platform. The first field tests were expected to begin in February 2014 and continue until July. The project is being funded by a FAPESP-Sabesp agreement and has already resulted in a potential patent that may soon be filed with the Brazilian Industrial Property Institute (INPI). It addresses the use of the smartphone in geophone systems and other technical changes they implemented to produce and record digital signals in the field.
Another innovative product that is expected to result from the joint Sabesp/Poli-USP projects financed by FAPESP is an electronic microlaboratory to measure the amount of phosphorus in water, either from springs or treatment plants, in real time. “Phosphorus is a nutrient and its presence in large quantities in the water catchment basins indicates the presence of organic matter—possibly sewage, often discharged illegally,” says Zuffo. Phosphorus acts as a nutrient for algae. Alga monitoring needs to be performed regularly because proliferation can impair potable water treatment and result in losses for the company. Currently, monitoring the springs takes a long time. Water samples must be taken, often using boats, and taken to a laboratory for analysis. “This takes a long time,” says Zuffo.
Professor Antônio Carlos Seabra’s group, at the Poli-USP Electronic Systems Engineering Department, proposed autonomous real-time monitoring using equipment the size of a credit card, attached to a buoy. Based on “lab on a chip” technology, the system is riding the current trend of chemical and clinical analysis, in which devices are miniaturized and use fewer samples and reagents. “We transferred the laboratory to a card the size of a credit card, but slightly thicker,” says Seabra, who also worked on the project in collaboration with the group headed by Professor Dione Morita, of the Poli-USP Department of Hydraulic and Environmental Engineering. “We used micromanufacturing techniques and knowledge of chemical analysis,” says Seabra.
The device contains microchannels through which water and reagents travel before reaching a point inside the card where a set of LEDs illuminates the sample and the transmitted light is captured by a sensor. “For example, a particular reaction can generate a blue color and you can determine the amount of phosphorus based on the intensity of the color,” explains Seabra. The job of the sensor is to prepare the sample, combine it with reagents, and analyze the intensity of the light at a wavelength that is absorbed by specific molecules involved in the reaction. The water and reagent inlets are controlled by micropumps and microvalves that sample the liquid from the environment. The device also expels the sample and cleans the system automatically. “We need to make the device capable of providing hourly measurements, to satisfy Sabesp’s needs,” says Seabra. The microlaboratory can be installed on a buoy or a on a base at the treatment plant. The information gathered is passed on to the company’s technicians via wireless systems. The buoy also contains a chamber that stores the reactants that wlll be injected into the device.
“We are now building a prototype that we will deliver to Sabesp for initial field tests and are also attempting to decrease the amount of sample used in the device. Today we use 800 microliters [800 millionths of a liter] and we believe that we can reduce this to 20 microliters,” says Seabra. The use of a smaller sample will also result in a decrease in the quantity of reagents and, consequently, operating costs.
To make the body of the microlaboratory, the researchers used a malleable ceramic that resembles plastic. After several layers are pressed together, it becomes rigid. The channels are created with a laser machine purchased as part of the FAPESP-Sabesp project for $250,000. “The channel widths must have a precision of ± 0.01 mm,” says Seabra. “We want to give the company an industrially reproducible and reliable product.” At least one patent is already certain to be filed with the INPI. This is the integration of the water pH microsensor, which required a novel solution to adapt it to the internal flow of the microlaboratory.
The USP patents are filed jointly by Sabesp and FAPESP, with ownership divided between the three entities. There are various possibilities for the ultimate use of these new technologies. They could be licensed or sold to companies already established in the sector or result in new start-ups. Sabesp could also set up another company to manufacture and sell the equipment. “The important thing is to develop the market for sanitation products in Brazil,” says Zuffo.
A device developed by engineers at Sabesp’s technology center and expected to be in its product portfolio is a biofilter to purify the gas emanating from wastewater treatment plants (WWTP) and sewage pumping stations, which is responsible for an unpleasant odor and is harmful to residents living near the plant. “It was made with recyclable materials and does not consume chemicals,” Zuffo says. The biofilter consists of peat formed from plant debris, wood and coconut shells, plus a layer of gravel. It is installed inside a container, and the gas enters via ducts. Water sprayed inside the container causes bacteria in the material to oxidize the gas. A prototype is operating in the testing phase now, with good results, at the São Miguel Paulista district WWTP in the state capital. “It’s almost ready to use and someone will have to mass-produce it,” says Zuffo.
Sabesp’s technological change of course is also intended to expand business and its share in the sanitation market not only in Brazil, but also abroad. A government-controlled company, 50.3% of Sabesp’s shares are held by the São Paulo state government and the rest are traded on the São Paulo and New York stock exchanges. Net income in 2012 was R$10.7 billion, with 7.7 million water supply connections, 68,000 km of water distribution networks, and 46,000 km of sewer networks. The company already has bases of operations in Panama and in some Central American countries, where it wants to take its new knowledge. It also has partnerships with sanitation companies in the states of Alagoas and Espírito Santo.
1. Specialist System for Detection and Diagnosis of Leakage in Urban Water Supply Networks (FAPESP-Sabesp) (nº 2010/50773-8); Grant Mechanism Partnership for Technological Innovation Program (PITE); Principal Investigator Linilson Rodrigues Padovese, USP; Investment R$103,805.40 (FAPESP).
2. Autonomous Microlaboratories (MLA) for Continuous Monitoring of Phosphorus in Water (FAPESP-Sabesp) (nº 2010/50744-8); Grant Mechanism Partnership for Technological Innovation Program (PITE); Principal Investigator Antônio Carlos Seabra, USP; Investment R$263,388.80 plus $373,855.47 (FAPESP).