The Double-Acting Hydraulic Ram (DAHR) uses the principles of hydraulic ram technology to generate flow or pressure enabling a range of matched surface drivers to lift water from depth efficiently.
The DAHR uses hydraulic power from a surface drive pump to lift water efficiently with only a few mechanical components, no electrical components and no sliding seals. It therefore offers several advantages wherever robust, very low maintenance submersible pumping is required.
The DAHR technology has many potential applications including irrigation, water supply for drinking and sanitation, building services, high ball passage pumps and in applications where it is advantageous to increase the Net Positive Suction Head (NPSH) of a surface pump to a higher limit. It is well suited for deep-well or borehole pumping applications and could be used for pressurising surface water for long distance horizontal or vertical water transport. Some common examples of existing pumping systems that will see significant advantage from a DAHR pump are:
Both manual and powered suction pumps are limited to lifting water from around 7-10m depth. By installing the DAHR at depth and utilising the surface pump output power to drive the DAHR, the lifting range of the surface pumps is greatly extended, affording a significant increase in application range and versatility. The DAHR could either be retro-fitted to existing surface drivers or combined with new surface drivers, essentially converting them into submersible pumps.
Submersible pumps are used to lift water from a significant range of depths, exceeding the limited range of suction pumps. The DAHR is able to outperform many submersible pumps by coupling with a range of more efficient and cost effective matched surface pumps to lift water. This impact combined with greater versatility and efficiency is potentially highly disruptive to the submersible pump marketplace.
The DAHR can be coupled with solar-PV pumps for off grid applications in the smallholder irrigation or potable water supply sectors. Submersible pumps or cylinders are prone to failure as a result of submerged electrical components or sliding seals. Coupling an easily accessible surface driver with a robust down-the-well DAHR pump offers a more robust, less expensive and more efficient solution.
Hand Pumps and Community Water Supply
Handpumps are a common source of potable water for over 4 million communities throughout the developing world. It is commonly cited that up to a third of handpumps are not functional at any one time. There are a host of reasons for this that can be attributed to all stages of implementation from borehole design and construction into pump installation, maintenance and operations. Effective solutions to this problem need to address the range of causes. As GSM and PV scale up around the world there is opportunity to monitor the functionality of water points and implement new business models to pay for installation and maintenance. The DAHR is retrofittable to existing handpumps to improve potable water source functionality, lifespan, flow rates and resilience. Equally importantly, the DAHR is able to couple with new solar PV implementations to offer greater longevity and ease of maintenance, thereby improving the overall value of the package and proposition. Finally, the DAHR’s ability to operate at a range of depths means that new sources of water may become accessible to communities that were not viable previously.
The ability to operate without dynamic seals and bearings gives NIFTE devices a clear set of advantages over mechanical heat engines. Apart from unprecedented reliability and low maintenance, NIFTEs can be manufactured from very low cost materials using cheap and well established production techniques. This makes them economically feasible in application areas where pumps are not currently viable.
NIFTEs are capable of pumping many different fluids, from shear sensitive biological cultures to viscous and chemically, or mechanically abrasive media. They have a gentle pumping action and operate in almost total silence. NIFTEs can be tuned during operation to suit a range of different pumping head and flow requirements, and available power sources.
Another key attribute of NIFTEs is their ability to use heat as a power source. Vapour cycle NIFTEs are particularly well suited to using heat at low temperatures, such as the waste heat from process loads or heat obtained from solar thermal collectors. This makes them well suited to applications in remote areas or hostile conditions, or helping users to meet increasingly stringent emission standards.
NIFTEs can also use cool sources for power, taking their input heat from the ambient environment. They are capable of adding or taking heat from the fluid being pumped. This attribute can be adjusted to suit a wide range of applications from those in which no heat flows into or out of the pumped medium, to those in which almost all of the heat flow passing through the system is added to, or removed from the pumped medium.
NIFTEs are self-starting, and require only small temperature differences to excite and sustain oscillations. Furthermore, they do not require active control systems, electronics or other costly or fault prone components to operate.
There are a number of applications in which one, or a combination of the unique features of NIFTE devices make them highly competitive with existing technologies. In many cases NIFTE devices open up the possibility of pumping, heat pumping or compressing where it isn’t currently considered to be an option.