Design and Construction of a Solar Pond and Desalination System for Coupling with Irrigation
Creators: name: MASCIALINO, CLAUDIO
Publisher: name: University of Surrey
Year: 2022

description: Most of countries in the world, especially those near the tropics of Capricorn and Cancer, are struggling to address water and food security. The increase in population and consequent demand for food and water resources combined with ever-diminishing natural resources are driving these countries to find sustainable and long-lasting technologies to address these problems and provide for the survival of their peoples. Fresh-water access and consequently water desalination in many cases will be a key element for their future development, independence and stability, especially if derived from sustainable resources.
description: Desalination technologies available today are mostly designed and engineered for large-scale applications associated with cities and industry. The use of these technologies for small-scale distributed fresh-water production especially linked to irrigation of crops is most of the time economically and technically unfeasible. Thus small-scale desalination technology is needed in very poor countries, arid regions and remote locations where access to energy and technology is limited and consequently it is very important to develop technologies or even better techniques that can be easily arranged with simple local products (possibly already used for the daily life needs of the population) managed by unskilled people and requiring a low amount of energy that should preferably be obtained from Renewable Energy Sources (RES).
description: To improve agricultural production in arid regions and remote locations, it is not only important to choose an efficient and reliable desalination technology but also to combine it with the right crop cultivation technique, choosing the best soil mixture and the suitable crops/plants that can grow within these limitations. Thanks to the support of the Ministry of Agriculture and Fisheries of Oman (MoAF) and the cooperation of a private company Aquama Ltd, the opportunity to build and test a suitable Solar Pond in Oman was offered together with novel irrigation and distillation techniques for crop and date palm growing. A direct seawater enhanced evaporation subsurface irrigation technique (SWI) and a direct seawater distillation technique (SWD) have been developed and some experimental work has been performed to validate the findings. The Solar Pond is demonstrated to have major limitations in its applications due to the extreme difficulties in its construction and maintenance in such an adverse climate. Thus, it is advisable to replace it with other simple, more reliable technologies such as flat solar panels or heat pipes. However, both SWI and SWD have shown potential for future applications in this context and the results obtained in terms of water production have been satisfactory.
description: The SWI and SWD systems have been modelled and the good agreement with the experimental results offers another important tool to predict the systems’ behaviour at full scales and in differing local conditions and underpins the derivation of costs.
description: The predicted low capital and operational expenditure, combined with the acceptable productivity of the systems, demonstrates their potential compared with other experimented solutions and highlights the promising conditions for continuing the experimental research.