Fecal Sludge Dewatering

FECAL SLUDGE DEWATERING

REQUEST FOR INVENTION (RFI)

RFI-150112 Circulation Date: December 2, 2015

Close Date: July 1, 2018

Key Words: sludge thickening, sludge dewatering, latrine emptying, vault emptying, black water, septic tank emptying, pit toilet, sewerage treatment, sewage pre-processing, Global Good, Bill and Melinda Gates Foundation, Omni-Processor, Omni-Ingestor.

Please read the instructions for Submission for more information on method, terms and conditions of your submission of Solution Reports. For the most recent closing date for all Requests for Invention please log in to your account at http://network.xinova.com. REQUEST FOR INVENTION Summary

Xinova seeks the disclosure of inventions that feature debris extraction, sludge thickening, and treatment enables the rapid dewatering of fecal sludge. of extracted effluent. The aim of the Omni-Ingestor system is to make fecal sludge emptying a viable business model by Globally, about 2.6 bil ion people lack access to even a simple improving sludge extraction in urban slums. ‘improved’ latrine. An improved latrine, per the World Health Organization (WHO), is the “hygienic separation of human The greatest technical challenge faced in this endeavor is excreta from human contact.” This lack of access results in the development of a fecal sludge thickening and dewatering serious health problems such as the transmission of E. coli and module that reduces the volume of fecal sludge by removing cholera resulting in life-threatening diarrhea. water; thereby making it easier to transport. Current sludge thickening technology is either too large or too energy However, even with improved latrines, the inevitable need intensive for this application. This RFI seeks a sludge for emptying them creates the same potential for the thickening or dewatering solution that fits into the Omni- aforementioned health problems. Improvements in the safe Ingestor footprint and is capable of dealing with sludge that handling of fecal sludge during the pit emptying process has highly variable physical and chemical properties. will significantly improve health outcomes for the billions of people living in communities who rely on this method of waste Desired invention characteristics and some suggested areas of disposal and the billions more who will likely obtain improved exploration are described on page 13. latrines in the coming years.

The Bill and Melinda Gates Foundation has already invested This RFI is released in partnership with Global in the development of a mobile sewage collection and Good. Refer to the “Awards for Selected pre-processing system called the Omni-Ingestor that will Solutions” section for more information.

Summary ...... 1 1.0 The challenge ...... 4 2.0 Current Technology & Prior Solution Attempts ...... 7 3.0 Possibilities ...... 13 4.0 The market ...... 15 5.0 References & details ...... 17

Problem Definition

SLUDGE DEWATERING MODULE The Bill and Melinda Gates Foundation (BMGF) aims to address the global sanitation problem holistically by supporting a three-pronged, sustainable approach to the This RFI focuses on a critical sub-component of the Omni- fecal-sludge life-cycle in developing countries: Ingestor - the sludge dewatering module, which must be mobile, rugged and economical to meet challenging ●● Reinvent the toilet, which addresses individual users, operating conditions. The BMGF wishes to harness market forces to make fecal sludge removal a self-sustaining success, ●● Omni-Processor, which addresses public toilets and and research conducted for BMGF suggests that business latrines and, model viability is highly dependent on the performance of the sludge dewatering module. ●● Omni-Ingestor, a fecal sludge remover. Higher performance dewatering would improve manual The Omni-Ingestor is a mobile pump and pre-processor of emptiers and standard vacuum tankers by reducing the sludge extracted from septic tanks commonly found in such volume required for storing sludge emptied from pits prior to places as urban slums. The objective of the mobile pre- transport. Thickening liquid fecal sludge from three percent processor (MPP) is to reduce human contact with unsanitary total solids to six percent total solids will reduce volume waste and reduce environmental damage from said waste. by fifty percent. The result is that a greater number of pits could be emptied between trips to discharge solids and the Basic requirements of the MPP system include extracting operational efficiency and revenue are significantly increased. debris and heavies (sand, grit, rocks, glass, and metal) from the incoming sludge, rendering those materials safe for It’s important to note that both thickening and dewatering human contact and disposal, thickening the remaining sludge are methods of solids concentration and volume reduction. by dewatering, and treating the effluent so that it is safe for Only the degree of volume reduction is different. Commercial re-use. Closing the loop, the Omni-Processor prevents human processes for thickening and dewatering are classified by waste from reentering the environment, greatly reducing the the total water content remaining in the sludge following impact to human health. treatment. Thickening processes typically increase total solids (TS) concentration by 5 to 10 percent, while dewatering increases TS concentrations by at least 20 percent. For liquid FECAL SLUDGE DEWATERING .RFI-150112 | © Copyright 2018 Xinova, LLC 4 REQUEST FOR INVENTION

fecal sludge with a high water content, thickening processes for all to both improved water and sanitation would reduce are oftentimes used upstream of dewatering equipment to the number of episodes of diarrhea globally by 16.7%. Access increase dry matter and facilitate handling. to in-house regulated piped water and sewerage connection with partial treatment of waste waters, could achieve an Another technical issue for the dewatering module is that average global reduction of 69% for diarrhea cases. the material to be processed consists of highly variable vault contents, which makes it difficult to process. The condition of A specific example of fecal contamination can be found in the sludge is expected to range from nearly-complete liquid Kiberia, the largest slum in Nairobi. With a population of 1.5M, (e.g. water from the environment, gray water, and bio-derived residents share a total of 600 toilets (1,300 people per toilet). water containing both dissolved and suspended solids of The prevalence of diarrhea is 32% of population of children widely-varying composition and concentration) through below 5 years of age (versus 16% of nationwide population). mostly viscous semi-solids (i.e., classic ‘fecal sludge’) to quite Over 18,000 children die annually from diarrhea related consolidated solids having a wet clay-like texture. deaths in Kiberia. With access appropriate sanitation 3,600- 5,400 (20-30%) lives could be saved annually Kiberia. The variability of the vault contents reflect tank/pit fill time- intervals ranging from weeks to years in service environments The majority of households in developing regions lack access ranging from single-family dwellings to apartment blocks, and to a piped sewer system or access to any sanitary latrine. various vault construction practices and drainage situat ions. Only 13% of the households in Africa and 18% in Asia are Vaults will typically include a scum layer on top and progress connected to the piped sewerage network, while 47% in Africa with depth to water-density liquid, through ever-denser sludge and 30% in Asia rely on non-piped sanitation systems, with in intermediate levels to consolidated and ‘mechanically the remaining households not having any access to substantial’ material at the bottom. As such, the system must sanitation facilities. be able to respond quickly to changes in the sludge properties and cannot rely on inputs from well-trained operators. The majority of cities in developing countries rely on informal services for excreta disposal. While latrines may be “improved” the inevitable need for emptying creates the Background potential for a significant risk to public health. There are two methods of emptying non-piped sewage systems: manual About 2.6 billion people – half the developing world – lack and mechanical. even a simple improved latrine. An example of in improved latrine is one with a hygienic cover slab or floor that covers Not only is contact with human excreta unavoidable during the pit where the excreta falls, which fulfills the WHO manual emptying, the fecal sludge itself is often disposed – definition of separating humans from the excreta. In addition, even in the case of mechanical service providers – directly the slab inhibits flies from carrying disease from the latrine into the environment without treatment. This can result in to food. Examples of unimproved latrines are facilities that communities that have made progress in increasing access lack a slab or simply open defecation. Because waste from to improved sanitation seeing the benefits of this progress unimproved latrines easily spreads, 1.1 billion people have no negated by the fact of living in and around fecal sludge that access to any type of improved drinking source of water. Even has merely moved from their toilets to their with improved latrines, unsafe methods used to capture and immediate environment. treat human waste contained in those latrines result in serious health problems and death.

Failure to properly deal with fecal matter causes food and water to become tainted resulting in 1.5 to 1.7 million child deaths every year. Most of these deaths could be prevented with the introduction of proper sanitation, along with safe drinking water and improved hygiene. Additionally, access FECAL SLUDGE DEWATERING RFI-150112 | © Copyright 2018 Xinova, LLC. 5 REQUEST FOR INVENTION

Why This Problem Is Valuable to Solve

Besides decreasing disease, improving access to sanitation can also bring substantial economic benefits. According to the WHO, improved sanitation delivers up to $6 in social and economic benefits for every $1 invested because it increases productivity, reduces healthcare costs, and prevents illness, disability, and early death.

Furthermore, to date, the majority of work in dedicated to improving sanitation in developing countries has focused on household or community latrine acquisition or sewage Table 1: Top 15 Profitable Fecal Sludge Emptying Businesses treatment and reuse, while one of the largest sanitation Based on Truck Cash Flow (Source: Chowdhry, S., Koné, D.) problems continues to be inadequate methods of emptying non-piped sanitation systems. The development of a more Access to mobile emptying equipment that enables sustainable and cost effective method of fecal sludge easier access to pits and septic tanks, improved fuel emptying would empower local authorities or businesses efficiency, and increased holding capacity would facilitate owners to provide sludge emptying as a service. entrepreneurs in developing countries to build economically and environmentally sound businesses all while increasing Emptying and transporting fecal sludge has been proven sanitation and health in the community. to be a profitable business in developing countries. The potential revenue that has been largely untapped because local authorities or business owners are unable to access the capital or equipment required to start such an operation. The majority of business owners in developing countries that operate fecal sludge emptying services are only able to purchase second-hand trucks that are fuel inefficient and require frequent maintenance. Truck owners in Africa have an especially difficult time due to a limited amount of available spare parts for a wide variety of different models of trucks (Chowdhry, S., Koné, D.).

Currently dewatering technologies are limited by large Emerging Technologies: footprints, high energy expenditure, or extended residence time requirements. Passive dewatering techniques such as ●● Flotation – Anoxic Gas drying beds or gravity thickeners can be operated with little to no energy or chemical additives, but the dewatering process ●● Metal Screen Thickening requires significant land use and extended residence time (up to 4 to 8 weeks). Mechanical thickening technologies are capable of much faster liquid solid separation times, but have Dewatering orders of magnitude higher acquisition and operational costs. Established Technologies:

The sludge thickening and dewatering technology field ●● Belt Filter Press includes a number of technologies ranging from fully commercialized to experimental (EPA): ●● Centrifugation

●● Chamber Press (Filter Press) Thickening

Established Technologies: ●● Drying Beds

●● Rotary Drum Thickening (Vacuum Filtration) Emerging Technologies:

●● Gravity Thickening ●● Electro dewatering

●● Gravity Belt Thickening ●● Inclined Screw Press

●● Membrane Thickening ●● Textile Media Filtration

Thickening

Thickening technologies are used to reduce the volume and increase the concentration of solids in sludge entering subsequent solids processing steps.

Rotary Drum Thickening (Vacuum Filtration) A rotary drum thickener – or a rotary vacuum-drum filter – is used widely in a variety of thickening applications such as the treatment of wastewater and dewatering pulp/paper sludge. The drum consists of a rotating drum covered with cloth or other semi-porous textile. The drum is submerged in a slurry, or sludge, and sucks solids onto the surface of the textile while rotating out of the liquid/solid mixture. The vacuum continues to dewater the caked solids on the drum until they are discharged before the drum re-enters the liquid/solid slurry. The drum is rotated with a variable speed drive that and are Figure 1: Rotary vacuum-drum filter – Source: Wikipedia usually operated between 5 to 20 rpm. Commons

Features Advantages Disadvantages TS in final Low capital cost Requires high concen- Gravity Thickening product: 4–10% Low space requirement trations of polymer Energy Odor control due to addition A gravity thickener is one of the easiest and cheapest requirements: enclosed system Usually requires addi- methods for thickening sludge. It is a settling tank that 10–30 kWh/ Continuous operation tional wash water for metric ton of Flexible operation drum cleaning concentrates solids by gravity induced settling and solids (drum speed and poly- Can require significant compaction. Gravity thickeners are typically used to thicken mer feed rates) operator attention primary solids and can be used without any chemical addition. They consist of a rectangular or circular tank with a sloped floor. Gravity thickeners can be operated in continuous or batch operation and are favored for their flow equalization and storage capacities. Overflow rate is the rate at which water moves out of the tank and can range from 0.2 to 0.4 liters per second per square meter. Gravity thickeners require significant space and settling time and are unlikely to be an appropriate technology for a mobile dewatering operation.

Features Advantages Disadvantages TS in final product: Simple operation Cyclic operation 2–15% depending on and maintenance Require significant residence time. Very low cost footprint Energy requirements: Low power require- Poor odor control 0–20 kWh/metric ments ton of solids No polymer required

Gravity Belt Thickening (GBT) Dissolved Air Flotation Thickening (DAF)

Gravity belt thickeners operate by laying sludge on a porous DAF thickening reduces the specific gravity of solids in fecal horizontal belt while free water drains by gravity. The feed sludge to less than that of water by attaching microscopic air rate is a key operational control for GBT processes and it is bubbles to suspended solids. The flocculated particles then typically at or below 10 liters per second for each meter of float to the surface of the tank and are removed by skimming. belt width. GBT is heavily reliant on polymer dosing, but has a It can achieve 2 – 5% total solids in the thickened sludge with relatively small footprint. only moderate polymer dosing. However, DAF is a clarification process not suitable for sludge with high density solids. Features Advantages Disadvantages Gravity thickeners are generally used for primary sludge TS in final product: Can be automated Requires high instead of DAF because of better performance with variable 4–7% Limited operation concentrations of Energy requirements: and maintenance (if polymer addition or primary sludge. 10–60 kWh/metric feed rate is regular) Poor odor control ton of solids Smaller footprint Belt requires regular cleaning and is easily damaged Flotation – Anoxic Gas (Recuperative Thickening) Membrane Filtration Using anoxic gas in DAF thickening processes has been Membrane filtration can be used for thickening or dewatering applied as a supplemental process to increase the speed and is similar to membrane bioreactors (MBR), which of anaerobic digesters. In pilots it achieved 6- 10% solids are widely used in the wastewater treatment industry for concentration in the final product. The process involves activated sludge treatment. Membrane units are submerged removing digested biosolids from an anaerobic digestion in a basin with suspended biomass and create a barrier for process, thickening with anoxic gas, and then returned to the the solid-liquid separation. There are many different suppliers digestion process. It also has been shown to improve odor of both off-the-shelf and custom membrane systems. Some control compared to traditional flotation thickening. of the different types of membrane configurations include: tubular, hollow-fiber, spiral wound sheets, plate and frame, and pleated cartridge filters. Thickening up to 4% solids Metal Screen Thickening has been reported for fecal sludge, though an aerobic Sludge thickening with metal screens is a new technology that environment is required for non-activated sludge. has been previously piloted, but has no full scale operations. The system uses a set of slit screens that are installed in a Features Advantages Disadvantages mixing tank. Thickening occurs by low pressure cross-flow TS in final product: No polymer addition High capital cost filtration through the screens. The screens feature sub- 4% 0.5-6kwh/t Relatively small Complicated for thickening, footprint maintenance and millimeter openings. 30-90kWh/t for operation dewatering

Dewatering complicated to operate and have one of the highest energy requirements.

Features Advantages Disadvantages Belt Filter Press TS in final product: Enclosed unit – odor Requires skilled 4–20% (sometimes control operators and per- Belt filter presses use a combination of gravity drainage and higher) Versatile and com- formance is difficult compression to dewater sludge. The first stage of a belt filter Energy requirements: pact to monitor 20–300 kWh/metric Reduced footprint Maintenance is ex- press is similar to a gravity belt thickener, where sludge is ton of sludge Moderate polymer pensive and required conditioned with polymers then placed on a porous horizontal requirements skilled staff Low exposure to Noisy belt that allows free water drainage. The second stage further pathogens dewaters the sludge by compressing the sludge between two porous belts and applying pressure and shear force through rollers. Belt filter presses that are dewatering raw primary Chamber Press (Filter Press) sludge usually operate at 2 to 5 liters per second for every meter of belt width. Advances in belt filter press technology In a chamber press, the sludge to be dewatered is injected include the use of 3 belts and using larger rollers for applying into the center of the press and each chamber is filled in turn. gentle pressure when dealing with smooth sludges. Then the liquid portion of the sludge is filtered out through textile media by adding streams of compressed air or water. Features Advantages Disadvantages Chamber presses have been most widely used for dewatering TS in final product: Low energy require- Requires high levels mining slurries, but have been widely applied to other 15–32% ments compared to of polymers Energy requirements: other mechanical Poor odor control industries. They are typically only operated in batch processes 10–60 kWh/metric dewatering tech- Very sensitive to and are a relatively slow method of dewatering. ton of sludge niques sludge properties Relatively low capital Typically cannot be Can produce very automated Features Advantages Disadvantages dry sludge at high Difficult to clean TS in final product: High filtrate quality Low throughput pressures 15 – 20% Adaptable to a large Batch process range of sludge High polymer usage characteristics High operation and maintenance costs

Membrane Filter Press

The membrane filter press is a further development of the chamber press. It has reported to have shorter filter times compared to a chamber filter press, along with higher final solids content. Figure 2: Belt Press – Source: BDP Industries Drying Beds Centrifugation Drying beds are a simple, low-tech means of dewatering A centrifuge is a high speed process that separates fecal sludge that function well in arid regions. Many types of drying solids from sludge through centrifugal force. They have been beds require no energy, but all require large footprints and used in the wastewater treatment industry since the 1930’s have very long residence times. There are many different and are stil a commonly used technology. Centrifuges are one types of drying bed technologies such as, mechanical freeze- of the most versatile of all sludge dewatering technologies thaw, auger-assisted, vacuum assisted, and quick dry filter and can their operation can be varied in order to thicken or beds. Each of these can achieve shorter residence time than dewater sludge to desired levels. They are able to operate traditional beds, but usually require the addition of polymer within one of the smallest footprints, but they are also more FECAL SLUDGE DEWATERING .RFI-150112 | © Copyright 2018 Xinova, LLC 10 REQUEST FOR INVENTION

and/or additional energy requirements. All drying bed Screw Press technologies require significant land use. The screw press is a relatively new technology in the sludge Features Advantages Disadvantages dewatering field. It was developed in the pulp/paper industry. TS in final product: No energy consump- Very long residence Compared to other mechanical dewatering technologies, it is 20–45% tion time (7–42 days) Energy requirements: Very low O&M skill Cyclic operation a simple, low maintenance system. The slow rotational speed 0 kWh/metric ton of and costs Requires large foot- results in less noise than centrifugation and will reduce the sludge No chemical con- print sumption No odor control costs of long term maintenance. Screw press designs include Sludge removal is both horizontal and inclined configurations. Typical input flow labor intensive rates are between 1 and 5 liters per second.

Features Advantages Disadvantages Electro dewatering TS in final product: Odor control due to Lower throughput 20–25% enclosure than centrifuge Electro dewatering processes combine electro-osmosis Energy requirements: Reduced noise and High polymer re- and mechanical pressure to dewater sludge. It is a newer 10–30 kWh/metric vibration quirement ton of sludge Fully automated dewatering technology with only a few suppliers. It has been operation reported to have the added benefit of pathogen reduction Low operation costs Low power costs due to the electric field.

Features Advantages Disadvantages TS in final product: Small footprint High power con- 25–45% Possible pathogen sumption Energy requirements: and odor reduction Low throughput 150–500 kWh/metric Large water removal High capital ton of sludge possible

Figure 4: Inclined Screw Press – Source: Huber Figure 3: Electro dewatering – Source: Treatmentequipment.com

Electroacoustic Electroacoustic dewatering has been tested at the bench- scale. It uses electric fields in combination with ultrasound waves to existing dewatering technologies such as the belt filter press. Tests report that solids contents were increased by 3.4 to 10.4%.

Textile Media Filtration

Bucher Hydraulic Press

Bucher Unipektin manufactures a hydraulic dej uicing press Table 2: Summary of Sludge Dewatering Technologies that has been tested on biosolids in limited environments. The press consists of a cylinder and a moving piston that squeezes Batch the sludge while free water passes through porous cloth filter Ac- Oper- or Technol- quisi- Foot- Poly- elements. It can obtain 25% more total solids than a belt filter ating Odors Con- ogy tion print mer press, but is a batch process. Cost tinu- Cost ous Rotary Mod- Low Small Mod- Contained Contin- Drum erate erate uous (Vacuum Filter) Gravity Low Very Large None Not contained Contin- Thickening Low uous Gravity Mod- Low Mod- High Not contained Contin- Belt erate erate uous Thickening Membrane High Mod- Small None Not contained Contin- Filtration erate uous Dissolved Low Low Large Mod- Not contained Contin- Air erate (but reduced uous Flotation with Anoxic Gas) Figure 5: Bucher Filter Press – Source: Bucher Runipektin Metal Low Mod- Un- Un- Unknown Un- Screen erate known known known Thickening Geotube® Container Belt Filter Mod- Low Small High Not contained Contin- Press erate uous Geotubes® are geotextile tubes that are comprised of Centrifuge High Mod- Very Mod- Contained Contin- high-strength polypropylene fabric. The tube is pumped full erate small erate uous of sludge and the fabric retains fine-grain material while Chamber Mod- High Small High Not contained Batch allowing effluent water to permeate through the tube wall. As Press erate the water is drained from the tube, additional sludge can be (Filter Press) added. Once filled with dried solids, the material is removed, but the Geotube® cannot be reused. A significant footprint is Drying Very Very Very Limit- Not contained Batch required and the technology is unlikely to be compatible with Beds Low Low large ed to None a mobile dewatering scheme. Electro High High Small Un- Contained and Semi- Dewater- known improved contin- ing uous Other Dewatering Technologies Screw Mod- Low Small High Contained Contin- Press erate uous Bucher Un- Un- Small Un- Contained Batch Hydraulic known known known Simon Moos KSA Press GeoTube® Low Low Large None Contained Batch Simon Moos manufactures KSA, a mobile dewatering system. The system is truck mounted and consists of a dewatering container and complete dosing system. It is capable of increasing total solids in fecal waste up to 10%. FECAL SLUDGE DEWATERING .RFI-150112 | © Copyright 2018 Xinova, LLC 12 REQUEST FOR INVENTION 3.0 Possibilities

Invention uggestions

Solution Characteristics

Xinova seeks fecal sludge thickening or dewatering ●● Limited Additives – No large batch dosing and mixing technologies that can reduce highly variable fecal sludge to of chemicals for coagulation/flocculation will be 80% or less water content while addressing the limitations possible. If a dosing system is utilized, it will have to (cost and size) of currently available systems. The technology be capable of responding to rapid changes in sludge should be developed with the following general goals in mind: properties. It would be advantageous – but not necessary – to have a sludge thickening process that ●● Simple and Robust Operation – The technology will does not require the addition of any consumables. be used by unskilled workers and must be easy to operate and maintain. The system should be able to In order to achieve these goals, the new technologies should accommodate sludge with highly variable properties meet the following technical requirements: without significant input from operators. To achieve this goal, the use of an advanced but maintainable sensor ●● Cost – The total operating expenditure should be less system that is compatible with the current Omni- than $5 USD per cubic meter of extracted waste in Injestor control system may be required. order to be economically viable.

●● Odor and Waste Control – It may be possible for a ●● Water Reduction – The technology must be able to limited amount of effluent to be sanitized and dumped reduce highly variable fecal sludge to 80% or less onsite. However, the majority of effluent water captured water content. from the dewatering process must be transported and sanitized. Some level of odor control will also need to ●● Processing Rate – Dewatering must occur at rates up to be designed into the dewatering system. 3 liters per second.

●● Size Restraints – The complete mobile pre-processing system, including the dewatering component, must fit into a volume less than 2 meters wide, 4 meters long, and 2.7 meters high. It also must be light and sized FECAL SLUDGE DEWATERING RFI-150112 | © Copyright 2018 Xinova, LLC. 13 REQUEST FOR INVENTION

appropriately to fit onto a truck along with other Omni- Ingestor equipment.

●● Power – The mobile pre-processing system typically has a 30hp generator providing power (220V, 50Hz), of which about 5-8hp is used for the pump. The dewatering system, needs to be energy efficient within this constraint.

Due to the space restraints, mechanical separation technology is more likely to fit into the requirements outlined in the Technical Problem section. Current mechanical dewatering processes can be complicated, difficult to maintain, energy intensive, and usually require the addition of polymer. Reducing the power consumption, complexity, cost, or polymer requirements for any of the following technologies or combining features from multiple technologies may be effective strategies.

Technologies with the most potential:

●● Screw press – Simpler operation and requires less energy than a centrifuge.

●● Electro dewatering – Has the added benefit of reducing pathogens in dewatered sludge.

●● Centrifuge – One of the smallest footprints and fastest dewatering.

●● Rotary Drum (Vacuum Filter) - Simple operation and maintenance.

●● Belt Filter Press - Simple operation and maintenance.

Current Market Review

A study evaluating 30 cities located in developing African and It was generally observed that emptying businesses within Asian countries found the market for fecal sludge emptying African and Asian countries were more profitable if they services has an estimated $134 million total market available. operated more than one truck. Table 1 in the “Why this Figure 6 illustrates this potential market by city. A similar problem is valuable to solve” section illustrates the profits study found that Latin American countries also have potential from the top ten businesses and how many trucks they markets for sludge emptying services and reported a market operated. There is a considerable amount of variability size of $1.8 to $5.3 million within just four cities between truck prices between different countries. Trucks (Chowdhry, S., Koné, D. (2012)). in Africa were generally used and imported from Europe, whereas Asian trucks were generally sourced locally. Figure 7 outlines the variability in cost and truck capacity between Asian and African trucks.

Figure 6: Market size for fecal sludge emptying services in developing countries (Source: Chowdhry, S., Koné, D.)

Figure 7: Average capacity and cost for fecal sludge vacuum trucks (Source: Chowdhry, S., Koné, D.)

Global Market

SLUDGE TREATMENT

The global market for sludge treatment and odor control Due to declining amounts of septic tanks in North America, is estimated to grow at a compound annual growth rate the need for emptying services is expected to decline. The (CAGR) of almost 6% the next four years. The overall market figure below shows that the amount of vacuum truck bodies is currently estimated to be worth $6.9 - $7.3 billion. The manufactured for septic tank emptying declined from 36.4% dewatering equipment market segment is driven by increases to 29.2% between 2006 and 2011. in sludge production (both industrial and waste related) and stricter sludge legislation, especially in European and North VACUUM TRUCK MARKET American markets. Currently popular technologies include centrifugation, belt filter press, and plate filter press (chamber press). For emerging dewatering and thickening technologies, The vacuum truck market manufacturers trucks for a price is the most important issue followed by diverse product segment. In North America, vacuum trucks dewatering abilities. range from very simple to very complex and are used for applications like hauling septic waste, cleaning sewer systems, and collecting forms of hazardous waste. The North American market for vacuum truck bodies and equipment has varied. It declined by 35% between 2008 and 2010, and then rebounded in 2011. The re-growth in sales is attributed to production of vacuum truck bodies that catered to the oil and gas industry (PR Newswire).

Figure 10: Vacuum Truck Body Manufacturing Categories (Source: SpecialtyTransportation.net)

Figure 8: Global municipal sludge equipment market (source: Global Water Intelligence)

Figure 9: Growth forecast for global sludge treatment market, by equipment (source: Global Water Intelligence) FECAL SLUDGE DEWATERING .RFI-150112 | © Copyright 2018 Xinova, LLC 16 REQUEST FOR INVENTION 5.0 References & details

Patent Landscape

A patent search for fecal sludge dewatering/thi ckening, Applications were from a wide range of countries with the mobile sludge dewatering/thickening, and fecal dewatering/ majority coming out of the United States, Japan, and China. thickening was conducted using patent applications on WIPO Because the type of sludge was not specified in this search, PatentScope. The purpose of the following is to give the many of the patent applications were related to industrial reader a rough idea of the state of the patent field for the sludge treatment, as well as wastewater. given technologies. It is not an exhaustive analysis. Search 3 Patent Applications by Region

SEARCH 1

Patent searches for specifically fecal or faecal sludge dewatering or thickening, only 6 patents were found. Three originated in China, one in Korea, two in Germany, and no U.S. patents were found.

SEARCH 2

For fecal or faecal dewatering/thickening, there were 44 results. The majority of these patent applications were filed by Figure 11: Mobile Sludge Dewatering Patent Applications by Procter and Gamble - and other diaper manufacturers - and Region were unrelated to large scale fecal sludge dewatering.

SEARCH 3

NOTABLE RELATED PATENTS INCLUDE THE FOLLOWING: BACKGROUND

1. (US20120312755/CA2779732) Aqua-Pure Ventures Inc - (WHO) http://www.who.int/mediacentre/factsheets/fs330/en/ Mobile clarifier and sludge dewatering system for onsite waste water treatment (BMGF) http://www.gatesfoundation.org/What-We-Do/ Global-Development/Water-Sanitation-and- 2. (US6379547) AB Aqua Equipment Co. - Mobile unit and method for purifying sludge and waste water. Hygiene http://www.iwmi.cgiar.org/Publications/wle/rrr/resource_ 3. (JP2008036623) Shin Meiwa Ind Co Ltd - Sludge-thickening recovery_and_reuse-series_2.pdf device and truck provided with the same (Chowdhry, S., Koné, D.) http://saniblog.org/wp-content/ 4. (CN103936257) Hunan University - Mobile sludge dewatering uploads/2012/12/10-country-FSM-Final-Report_September- device with modification reaction device and dewatering 2012-1-2-copy.pdf method

TECHNOLOGIES 5. (CN103896473) Sichuan Demo-Scimee Science and Technology Co. - Deep electroosmotic dewatering device of sludge http://www.weat.org/events/2012MossWEATDewateringTrends. pdf 6. (kr101192472) Sedimentated dewatering vacuum truck capable of improving separation efficiency of a sludge and http://www.iwmi.cgiar.org/Publications/wle/rrr/resource_ water recovery_and_reuse-series_2.pdf

7. (CN102642956) Beijing Richway Runcheng Water http://www.usfabricsinc.com/products/ecotube-sludge- Technologies Ltd. - Mobile water treatment system dewatering-tubes

Search 3 Prominent Patent Applicants (EPA) http://water.epa.gov/scitech/wastetech/ upload/2007_04_24_mtb_epa-biosolids.pdf

Ab Aqua Equipment Amukon Kabushiki Kaisha Alb. Klein MARKETS Kg Baker Hughes Incorporated Severn Trent De Nora, Llc http://www.wateronline.com/doc/sludge-management- equipment-market-set-reach-by-0001 Other Main Applicants Bulgarska Ishigaki:Kk Industrialna St http://www.bccresearch.com/market-research/environment/ Taiheiyo Cement municipal-industrial-sludge-treatment-odor-control-env010c. Ecolab Usa Corp Container- html Care Internatio https://www.frost.com/prod/servlet/report-brochure. Figure 12: Main Patent Applicants - Mobile Sludge Dewatering pag?id=M10B-01-00-00-00

http://www.prnewswire.com/news-releases/vacuum-truck- body-manufacturing-in-north-america-market-size-shares-- analysis-212297701.html

Awards for Selected Solutions

We will conduct a global review of your invention using a team of experts who will examine the technology, potential products, markets, future customers and existing landscape.

We will select the best proposed solutions gathered during the circulation period of this RFI.

We will pay any awards in installments, as per your written and executed contract with us.

Notices

Please contact:

Xinova, LLC 701 Fifth Avenue, Suite 4100 Seattle, WA 98104 USA

Xinova Asia Pte. Ltd. 150 Beach Road, # 08-06/08, Gateway West Singapore 189720

Inquiries: David Kraft [email protected]

Instructions for Submission

Please read carefully before submitting Solution Reports

●● Terms and conditions of this RFI apply to anyone submitting proposed solutions.

●● We accept only original, new and novel proposed solutions. Proposed solutions not satisfying these requirements will not be considered.

●● Please direct any questions you may have to your local Xinova office. Suggestions to refine, broaden or to include new information are welcome. Any suggestions you provide are given entirely voluntarily and shall not create any confidentiality obligation for us. We may use the suggestions without obligation or restriction of any kind.

●● You may submit one or more Solution Reports during the circulation period of this RFI. Please see the first page for the circulation period. We will not accept any proposed solutions after the RFI Closing Date.

●● Please contact your local Xinova office for the Solution Report form. Please fill out the form accurately and completely. Incomplete forms may be returned to you for further action and may not be considered for acceptance.

●● Each proposed solution should be embodied in one Solution Report form. Do not include multiple proposed solutions in one form.

●● We reserve the right to cancel or terminate this RFI at any time.

●● We may share information on select proposed solutions and/or provide feedback to some or all of the inventors who submitted Solution Reports in response to this RFI. All information shared and/or feedback provided is our confidential information.

●● We will not retain any rights or obligations with respect to declined proposed solutions.

Our worldwide locations

USA China India Japan Xinova Xinova Innovation (Beijing) Xinova India Xinova Japan GK 311 ½ Occidental Ave S Consultancy Co. Ltd. Mynd Solutions Pvt. Ltd. Yaesu Mitsui Building 6F Suite 300 No. 01-1108, B1185 Office Ground Floor No.4 2-7-2 Yaesu, Chuo-ku, Seattle, WA 98104 F10. No. 1 Bld of No. 8 Yard Victoria Road Tokyo 104-0028 Japan USA North Road of the Workers Stadium Bangalore, 560047 India +81 3 6478 6120 +1 (206) 800-2678 Chaoyang District, Beijing, China +91 080 43721272

Australia Korea Singapore Israel, Helsinki & Vienna Xinova Australasia Pty Ltd. Xinova Korea Yuhan Hoesa Xinova Asia Pte Ltd. Affiliate office Suite 1, Level 18 10th floor, Golfzone Tower 150 Beach Road 227 Elizabeth Street 735, Yeongdong-daero Gangnam-gu #08-06/08 Gateway W. Sydney NSW 2000 Australia Seoul 06072, Korea 189720 Singapore +61 2 8093 4850 xinova.co.kr +65 6408 5080 Xinova