PROCESS DESIGN OF NITROPHOS FERTILIZER BY UTILIZING NATIONAL PHOSPHATE RESERVES

Abstract

Nitro-phosphate (NP) is a complex acidic fertilizer which contains two macronutrients of plants, nitrogen (N) and phosphorous (P). NP is majorly used for rooting, blooming and fruit production of plants. Demand of nitro-phosphate is increasing day by day with increasing demand for food and population growth. Increasing demand of NP and alkalinity of soil in Pakistan motivates us to work on this project. Phosphate ore is an important raw material for manufacturing phosphorous chemical products. While most of the phosphate resources cannot be directly treated as feed stock due to the low grade of P2O5 and high content of silica and other metal impurities. For obtaining a qualified phosphate concentrate, the beneficiation of the low-grade phosphate ore is carried out to upgrade the P2O5 grade of phosphate ores from 20% to 28% using direct and reverse flotation techniques. This treated feed is used to make a NP fertilizer using ODDA Process. This report includes material and energy balance, designing along with HAZOP and EIA study. The designing of each equipment (reactors, crystallizer, heat exchangers, centrifuges, evaporator and prilling tower) with designing is discussed in detail. The cost estimation of this plant was a major and compulsory part of this report. The plant capital cost and operating cost are also determined along with payback period (2.25 years). The payback period of the project is 2.25 years