Improvement and technology transfer of the Parañaque-type solar salt making technology for industrial salt production

Abstract

A study on the improvement of the Parahaque type solar salt making technology was undertaken to develop and establish a practical, inexpensive and effective method of producing high quality salt. As an initial step, a survey was conducted by the Chemical Research Department (now CMD) of NIST (now ITDI) on the prevailing practices and status of the existing solar salt making technology in Metro Manila and nearby provinces. Interviews with salt workers and salt work owners including local officials were conducted. Assessments of local saltworks and salt making practices were made; problems of the industry were identified and areas for technology innovation and/or improvement were determined. Samples of solar salt products were taken for analysis. Recommendations were made and subsequently appropriate actions were taken to help promote the improvement and development of the local solar salt making industry. For two successive salt making seasons, a team of NIST researchers introduced and applied the scientific method for solar salt making in a typical one-hectare saltwork located in Bacoor, Cavite. Appropriate brine management and process control measures were devised and eventually practical experience was acquired. Data were gathered for assessment. The salt products as analyzed meet the specifications for industrial grade salt. Encouraged by the results obtained from the two demonstration saltworks, the improved solar salt making technology was subsequently applied during three successive salt making seasons in five privately owned saltworks as a technology transfer and joint R&D undertaking. This application of the ITDI technology was done side by side with the traditional salt making process of the respective saltworks. Production data gathered from both technologies were compared; representative samples of both crude and ITDI salt products were analyzed and the quality compared. The Parañaque type solar salt making technology can be improved to produce industrial grade salt through the application of the ITDI improved method. As shown from the results of the experiments which were done in comparison with the traditional method on a one to one crystallizer basis, the salt yield can be more than doubled; and since the product is of high quality and meets the requirements for industrial salt, its selling price can be 3 to 4 times higher compared to the traditional crude solar salt product. Consequently, the income that can be derived using the ITDI improved technology can possibly be increased by 6 to 8 times.