Author: Arij Ferzat ShekhaniPublisher:
ISBN:
Category :
Languages : en
Pages : 548
Book Description
Designing a chemical plant for producing hydrogen from the raw crude glycerol through steam reforming method which plays significantly and effectively in most of the chemical industries for obtaining hydrogen was performed in the design thesis due to its significant role in the industry and various aspects in chemical processes. The main purpose of the project is to produce 25, 000 tons/yr. of hydrogen from steam reforming of crude glycerol with high purity of 99%. The process is based on two main processes which are the purification and production processes, in the purification step, 90% of methanol will be removed and production step is needed for obtaining 99% purified hydrogen. The design has been studied from different aspects through the process flow diagram, required considerations and calculations of the units, energy and mass balances, techniques and processes, process economics, operating conditions, and environmental , ethical, and safety considerations which have been fulfilled. The objectives of the design project are to create an advanced , environmentally safe, and techno-economical plant for the production of hydrogen due to its valuable and effective role as a promising renewable energy source. Secondly, to design the plant in lower prices and costs which will help in the utilize of the methods, involved materials, and the desired hydrogen since there is a huge demand in the past decades until now on it. Various calculations of detailed design were made for three main equipment which are heat exchanger in shell & tube type, steam reformer in a packed bed reactor, and the absorber. Polymath software program was involved in the calculations of the steam reformer, and the observable results showed that the required catalyst weight of Ni/Al2O3 catalyst is 424.7613 kg to reach 95% conversion and with a diameter of 0.531 m. length of 1.593 m, (sic) and unknown cross-sectional area to make the weight catalyst calculation simple. For the chemical absorber which is used to purify the hydrogen (H2) produced in the steam reforming plant to 99% by absorbing the carbon dioxide (CO2) with a 15% MEA solution, the calculated cross-sectional area of the column is 1.375m2, where the corresponding column diameter of 1.323 m . however, the column diameter used for design is 1.3 m. The height of the absorption column was calculated to be 4.865 m after a series of steps. Also, the pressure drop per unit height was found to be 382.952 Pa/m.For the heat exchanger design, it was found that the number of tubes is 76 having an outer diameter of 3⁄4 ", a wall thicknes (sic) of 14 BWG on 1" square pitch, an internal dimeter (sic) of 0.584 in, (sic) and a length of 16 ft. The required heat transfer area was calculated to be 232.4778 ft2 for the calculated number of tubes of 74.1 tubes, while the designed area was calculated to be 238.76 ft2 for the 76 tubes chosen for the design. The internal shell diameter was also found to be 12 in. The baffles, on the other hand was assumed to be 25% cut segmental baffles with a baffle spacing of half the shell ID. It was also paramount to find the cost of the equipment designed and the estimation of the whole plant. The cost of the three-designed equipment was 6143.700 dollars, 44495.120 dollars, 2539.980 dollars for the heat exchanger, absorber, and the pressurized vessel (steam reformer), respectively. The total manufacturing costs, on the other hand, were found to be approximately 34 million dollars.