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The application of Appropriate Technology

Pumps, Wells & Boreholes

Posted on Oct 26, 2011

Information about different types of pumps as well as digging wells and boreholes.

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Centrifugal Pump Selection and Installation

Posted on Oct 25, 2011

Factsheet by the British Colombia Ministry of Agriculture, Food and Fisheries on the correct selection and installation of centrifugal pumps. Efficient operation of a pump can only be obtained by selecting the correct pump, as well as the proper selection and installation of suction and discharge fittings. The pump should be evaluated on a regular basis to ensure the pump is operating properly and is still sized correctly for the system, especially after any major system modifications. The most commonly used pumps in irrigation are centrifugal pumps, turbine and submersible pumps. Centrifugal pumps are a good choice to pump water from lakes, rivers, creeks or shallow wells. Horizontal centrifugal pumps commonly used for irrigation systems have total dynamic heads of less than 400 ft and suction lifts of less than 20 ft. This factsheet focuses on centrifugal pumps. Turbine and submersible pumps are used when pumping from wells with a static water level below 15 ft. Turbines are often used for total dynamic heads exceeding 450 ft. Submersibles are available up to 10 inch in diameter and motor sizes up to 100 hp. Read the while document as a PDF file (100...

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Photovoltaic Water Pumps

Posted on Oct 25, 2011

Short technical brief by the GTZ on photovoltaic pumping systems. In many developing countries, the inadequate supply of drinking and irrigation water is a severe problem. In rural areas with no access to grid power, national water authorities and private farmers have to rely on hand pumps and diesel-driven pumps, many of which are out of service due to technical defects or a lack of fuel. As a rule, hand-operated pumps are the least-cost option for low consumption rates and low pumping heads. If hand pumps cannot satisfy the demand, diesel driven pumps are commonly used for drinking and irrigation water supply. These pumps stand in competition with photovoltaic water pumps (PVP), which present themselves as a reliable and environmentally-sound alternative means of water delivery. Read the whole of this document as a PDF file (144...

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Rota Sludge & Stone Hammer Drilling

Posted on Oct 25, 2011

There are various techniques for drilling a drinking water or irrigation tube well. The drilling method used is related to the soil conditions and the financial means available. In general, drilling techniques can be divided into two categories i.e. drilling with a machine or manually. The greatest difference between the two methods is that drilling with a machine is much more expensive than drilling by hand. The manual method is thus the preferred choice for low-cost wells but it obviously has its limitations. If the ground is too hard like for instance solid rock, manual drilling is often not feasible and only machine drilling can be considered. In certain circumstances, digging the well by hand may be an option. However, there are certain disadvantages regarding the so-called “dug well”: the dangers while undertaking the work, the difficulty of penetrating deep enough into the aquifer, the relatively high costs and the poor hygienic conditions. Practica has since 1999, conducted research into the possibilities of manually drilling low cost tube wells. The objective is to make this method as efficient and inexpensive as possible so as to make wells affordable for a larger part of the rural population in developing countries. The research was initiated in North Bengal, India. There, drilling was done using the traditional Hand-sludge method. This technique could not pass hard layers or boulders and so additional tools were developed resulting in the Stone-hammer method. In 2001 these methods were further tested in Nicaragua. Here, a rotary movement was added, resulting in the Rota- sludge method. The Rota-sludge and the Stonehammer methods together form a package. Basically one drills with the Rota Sludge until one hits a layer with boulders or stones, then one uses the Stone-hammer to pass through this layer and finally one switches back to Rota Sludge when the boulders are passed. Part 1 of this manual describes, step by step, how the Rota sludge and Stone hammer method must be used and part 2 provides detailed drawings of the equipment. Part 1 Drilling Manual PDF file (2.2 mb) Part 2 Production Manual PDF file (0.5...

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Rope Pump Manual, Hand Dug Well & Borehole model

Posted on Oct 25, 2011

A good manual by the Practica Foundation on rope pumps for hand dug wells and boreholes. This manual is made as a guide for organizations and workshops which are involved in the introduction process of the manually operated Rope pump and for technicians to be trained in Production, Installation and Operation & Maintenance of the Rope pump models: ‘Hand dug well’ (AH) and ‘Borehole’ (AB). Experiences indicate that for a successful introduction, production and installation of Rope pumps on a large scale, the use of any production and installation manual has to be combined with hands-on training by an experienced trainer! The trainer will guide the organization and/or workshops through all aspects of the introduction and production process. Lessons learned from the past show that a number of small mistakes usually are made during the first years of production. However, these minor ‘mistakes’ can have a large influence on the life time and functioning of the pump. If these impurities are not corrected in time by a professional, the Rope pump option will gain a negative image amongst users and others in an almost irreversible way! It is therefore that it is strongly suggested this manual will only be used in combination with a professional training, whereby the manual will be distributed to the participants, who can later use it as a reference handbook. The practical training will focus on all essential aspects for producing and introducing the Rope pump. You can read the whole of this document as a PDF file (2.4...

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