Commercial feasibility of a supercritical extraction plant for making reduced-calorie peanuts

Contributions to supercritical extraction of vegetable substrates in Latin America

“…Since the cost of a plant increases as its capacity increases, there exist different criteria for inter-or extrapolating costs for a given capacity based on literature data for other capacities. One relationship states that (Passey, 1994):…”

“…For a given plant capacity, an increase in the number of extraction vessels results in savings in operational costs, at the expense of an increased investment. Solvent recycling and employment of an adequate solvent recovery system may allow decreasing the losses of CO 2 below 2% of all the solvent that is employed for extraction (Passey, 1994). Bravi, Bubbico, Manna, and Verdone (2002) report on extraction strategies that allow an estimate of the optimal number of extraction vessels, separation vessels, and solvent recompression cycles to be made by using as the objective function the total cost per unit mass of produced extract.…”

“…Table 7 summarizes the results of the application of Eq. (8b) to estimate the cost of a SCFE plant based on literature reports of plant costs from various literature sources, including different manufacturers of large scale systems such as Uhde from Germany (Kö rner, 1993), Separex from France (Clavier et al, 1996), Thar Technologies from the USA (Chordia & Robey, 2000), and Natex from Austria (H. Seidlitz, CEO, Natex Prozesstechnologie, personal communication), and the 4 · 2000 L plant in the commercial feasibility study of Passey (1994). Since the cost of the plant is subjected to variations due to exchange rates, inflation and pressure ratings, all values were re-estimated in US dollars of April 2003, for plants with a pressure rating of 400 bar by using: (i) historical currency exchange rates from the internet (www.oanda.com/convert/fxhistory); (ii) Chemical Engineering Plant Cost Index (CECPI) values, which are published monthly in Chemical Engineering (Vatavuk, 2002); and (iii) pressure-correction factors (PCFs) estimated from Hederer and Heidemeyer (1985) by linearization of a plot of equipment cost versus nominal pressure value (p nom , bar) for pressures between 100 and 500 bar:…”

“…where I 0 is the investment cost of a plant with a capacity C 0 , and k is scaling exponent factor (k = 0.6 for large capacity SCFE plants of up to 16 000 ton/year of raw material, Passey, 1994). Perrut (2000) has shown that the cost of a SCF system depends on both the total volume of the high-pressure vessels (V T , L) and maximal flow of the pump (Q, kg CO 2 /h) according to:…”

Economic appraisal of supercritical fluid extraction of refined cashew nut shell liquid

“…The cost of the commercial SFE unit is considered US$ 1,200,000 [10,11]. The annual labour cost is calculated on the basis two labors per shift, a plant engineer and two skilled technicians.…”