Enhancement of methane production from Cotton Stalk using different pretreatment techniques

Abstract

China produces large amount of cotton stalk (CS) residues as agricultural biomass, which are incinerated on-site, causing air pollution. The high organic content of CS could be utilized for biogas production, but the direct digestion without pretreatment always leads to a low methane yield and biodegradability, due to the complicated structure of lignocellulose. In order to search best fitting pretreatment methods in effective anaerobic digestion (AD) of CS, effects of various pretreatments including KOH, NaOH, Ca(OH)2, alkali hydrogen peroxide (AHP), H2SO4, H3PO4 and steam explosion (SE) were studied. It was seen that all treatments resulted in varying methane yields. Among all the pretreatments, acid pretreatment is not suitable for AD of CS. The results showed that the highest cumulative methane yield (CMY) of 192.4 mL·gVS−1 was obtained after 3% AHP pretreatment of CS, and the methane yield improved by 254.3% than the untreated CS. Therefore, AHP treatment was proven to be an efficient pretreatment technique. XRD and FTIR analyses had shown that pretreated CS had favorable structural changes. This research is beneficial in developing environment friendly and cost-effective pretreatment technologies to utilize CS for methane production in future application.

Impact of Alkaline H2O2 Pretreatment on Methane Generation Potential of Greenhouse Crop Waste under Anaerobic Conditions

“…This process also has the advantage of not leaving H 2 O 2 residue, and it is considered as an environmentally friendly and low-cost application [ 22 ]. While a large number of studies were conducted using alkaline H 2 O 2 pretreatment on various types of agricultural waste, such as corn stover, wood waste, soft wood, cashew apple bagasse, energy crops, sugar cane bagasse, agricultural crop stalks, and cotton stalks [ 19 , 22 , 23 , 24 , 25 , 26 , 27 , 28 , 29 ], this method, although quite promising, remains untested for greenhouse crop wastes.…”

Comparative Assessment of Biogas Production Potential of the Most Abundant Agro-residues in Turkey

“…Anaerobic digestion is a sequential process in which diverse microbial communities including hydrolytic, acidogenic, and acetogenic bacteria and methanogenic archaea interact mutually [9]. The lignocellulosic structures of agro-residues limit the hydrolysis rates which then affect the methane yields [9,25,26]. Thus, appropriate inoculum should be used during the start-up period which includes necessary microbial communities having an ability to degrade lignocellulosic feedstock.…”

Comparison of pretreatment methods that enhance biomethane production from crop residues - a systematic review

“…In contrast, three studies reported combined processes to be low energy-consuming. This observation was sustained byKumar and Sharma (2017),Zhang et al (2018), andKim et al (2019). It can be postulated that this variation in results is due to the complexity of combined methods and further research is needed.…”