(67c) Process Safety in Concentrated Solar Plants (CSP)

Heat Transfer Fluid (Synthetic Oil) and Thermal storage fluid TSF (sodium nitrate and potassium nitrate) can result into Process Safety Incidents of level Tier-1 and Tier-2 in Concentrated Solar Plants.

NOMAC is a leading O&M service provider of proven, safe and cost-effective O&M services of desalination and power plants in the Middle East, Africa and Europe having a portfolio of about 20,000 MW of power generation. NOMAC Operates & Maintains combine cycle, simple steam cycle, solar photovoltaic and concentrated solar thermal plants (CSP) and moving towards wind energy projects as well.

Heat Transfer Fluid (Synthetic Oil) and thermal storage fluid TSF (sodium nitrate and potassium nitrate) are being used in Concentrated Solar Plants to exchange heat with water. As a result super-heated steam is generated, which runs steam turbine to produce electricity through generator. Both these substances HTF & TSF have got excellent heat transfer capacity. But at the same time there is a high potential of Fire and Explosion. As TSF can oxide abruptly and can result into explosion and Fire if exposed to Air. Both these chemicals are being used above the threshold quantity defined by API-754. So this can result into TIER-1 and TIER-2 Process Safety Incidents. This paper discusses different incidents related to HTF and TSF in our CSP sites, which can be a lesson learn for exponentially growing CSP market, and can save people, equipment and environment from the Hazardous nature of HTF and TSF.

We observed serious HTF heat exchanger leakages where both these chemicals are coming in contact to exchange heat. This paper will enlist the root causes and contributing causes that jeopardized process safety. What controls we have adopted to get rid of these incidents in future. Incidents belongs to our sites in Morocco and South Africa.