Process Design and Economics of On-Site Cellulase Production on Various Carbon Sources in a Softwood-Based Ethanol Plant

Table 2

Annual costs, revenues, and profit of the proposed ethanol plant in MSEK. Carbon source A: pretreated liquid fraction, B: pretreated liquid fraction and molasses, and C: pretreated liquid fraction and pressed pretreated slurry with a total WIS content of 1%, 2%, and 3%; +: 1.5-fold specific activity.

	Reference	A	A+	B	B+	C1	C2	C3
Annual cost (MSEK)
Raw material	99.5	99.5	99.5	99.5	99.5	99.5	99.5	99.5
Capital	135.5	152.7	151.6	151.0	149.1	154.2	153.8	153.5
Chemicals	28.3	32.4	31.7	38.0	35.4	32.2	31.9	31.6
Enzymes	33.6	—	—	—	—	—	—	—
Utilities	2.3	2.5	2.4	2.5	2.4	2.5	2.4	2.4
Other	20.8	21.3	21.2	21.2	21.2	21.3	21.3	21.3
Total	320.0	308.3	306.4	312.2	307.6	309.7	309.0	308.3
Annual income (MSEK)
Ethanol^a	297.4	279.8	285.7	289.7	292.2	279.8	279.7	279.7
Co-products	45.1	45.9	45.3	48.5	46.8	46.1	46.5	46.8
Electricity	11.1	9.8	10.2	10.0	10.3	9.5	9.4	9.4
Total	353.5	335.6	341.2	348.2	349.3	335.4	335.7	335.8
Annual profit (MSEK)	33.6	27.2	34.8	36.0	41.7	25.7	26.7	27.5

^aEthanol price was assumed to be 5.5 SEK/L.