In this section of the brief, only the syntheticmanufacture of urea from ammonia and carbon dioxide (CO2)- which occurs as a by-product of hydrocarbon reforming - will beconsidered.
This white crystalline solid is an inexpensive form of nitrogen fertilizer with a proportionate compound mixture, i.e. NPK (nitrogen-phosphorus-potassium) ratio of 46-0-0. This implies that the mixture has 46% nitrogen. Even though urea is naturally produced in humans and animals, the manufacture of synthetic urea is done with anhydrous ammonia.
Elimination of the explosion danger in the urea synthesis unit
Commercially, urea is produced using two basic raw materials,- ammonia and carbon dioxide. Here, the carbon dioxide gas is made to react with anhydrous ammonia under intense pressure, at 350 degrees Fahrenheit. Urea is then processed to form granules or solid globules known as prills. For it, molten urea is sprayed down a tower, up which air is pumped. Being slightly smaller than Urea granules sold in market, these are especially beneficial when the fertilizer is being applied to the plants by hands. It’s important to note that huge quantities of carbon dioxide are produced when ammonia is being manufactured from coal or from hydrocarbons like natural gas and other petroleum derived raw materials. This facilitates direct synthesis of urea from the raw materials. Precaution should be taken to keep dry urea away from moisture until its use as it is extremely soluble. Apart from prills and granules, it is also produced as pellets, flakes, crystals and solutions.
- The natural gas passing to the process is ..
Vietnam has transformed itself over the past two decades from a poor communist state which needed to import food into one of the world’s largest rice producers and a vibrant south-east Asian economy which has joined the World Trade Organisation and which aims to become a mature economy within 15 years. Part of the key to this is development of the country’s agricultural sector, and the key in turn to that is domestic urea production based on Vietnam’s natural gas reserves.
Ammonia production from natural gas. - SlideShare
Urea is produced commercially from two raw materials, ammonia and carbon dioxide. Large quantities of carbon dioxide are produced during the manufacture of ammonia from coal or from hydrocarbons such as natural gas and petroleum derived raw materials. This allows direct synthesis of urea from these raw materials.
Ammonia production from natural gas
The specific features of the reactor with multi-stage and indirect cooling type configuration accomplish energy saving, i.e. efficient recovery of the reaction heat as steam generation. The generated steam is equivalent to about 50% of steam required for steam reforming of the corresponding syngas production for methanol synthesis. Compared with axial flow configuration, the radial flow feature of MRF-Z® reactor realizes reduction of pressure drop over the catalyst bed by about one-tenth and thus it is possible to save energy for recompression of unreacted synthesis gas up to the inlet pressure of the reactor. Furthermore, it is easy to scale-up along with the direction of the reactor height while keeping the size of reactor diameter, i.e. maintaining same pressure drop of the catalyst bed, and thus the possibly largest amount of the catalyst can be loaded in a single reactor vessel.
Ammonia production from natural gas, haldor topsoe …
CO2 is recovered from Natural gas fired boiler and steam reformer flue gas, compressed and used for urea production at Ruwais Fertilizer Industries plant in Abu Dhabi , United Arab Emirates. Start of operation was 2009.