An assessment of anaerobic digestion capacity in Bangladesh

Abstract

This work scopes the potential for existing common feedstocks to be used in existing types of anaerobic digester units to produce biogas in Bangladesh. A preliminary study identified three commonly occurring scenarios of smallholdings with cattle, poultry farms and daily cattle markets, which produce dung, poultry litter, and dung mixed with rice straw respectively. This third feedstock is proposed as a novel and significant newly recognised prevalent source. The main study involved carrying out surveys of representative samples of each of these (N=125, 125, 30) for the district of Gazipur in order to determine the distribution of herd and flock sizes, and thus the relevant biogas plant types and potential yields. The results were scaled up for nationwide figures, which approximated the total potential biogas energy from these feedstock types at 240 x10 6 MJ (240 TJ) per day, or 66.7 x 10 6 kWh, which in principle could meet the current cooking energy requirements of 30 million people in Bangladesh. Of this, 70% of the potential energy from AD could come from cattle feedstock (with 87% of this from domestic-sized plant); 16% from poultry feedstock (with 63% of this from medium-sized plant); and 14% from rice straw bedding from cattle markets (all requiring large or very large plant). There is potential for around 2 million domestic units, 340,000 medium units and 20,000 large or very large units that might be more suited for larger users such as businesses, schools or hospitals.

Potential of biogas production from biomass and waste materials in the Small Island Developing State of Mauritius

“…AD is the breakdown of organics by a group of microorganisms in an environment deprived of oxygen to produce a biogas consisting of mainly CH 4 and CO 2 and a digestate of high nutrient content that can be used as bio-fertiliser [12,44,45]. AD occurs through 4 main phases namely hydrolysis, acidogenesis, acetogenesis and methanogenesis [46].…”

“…A general trend that has been adopted by many countries is to shift from fossil fuels towards renewables; particularly the conversion of biomass and waste materials to energy [9,10]. This interest towards renewables has also reached the developing world as evidenced by numerous studies performed on the potential of bio-energy in developing economies like Albania [11], Bangladesh [12], Brazil [13], Cameroon [14], China [15], Ethiopia [16], Ghana [17,18], India [19][20][21], Malaysia [22][23][24][25], Mexico [26], Nepal [27], Nigeria [28], Pakistan [29], Sri Lanka [30], Uganda [31] and Zimbabwe [32,33], among others.…”

Energy yield potentials from the anaerobic digestion of common animal manure in Bangladesh

“…on domestic life, and those all require the availability of reliable field data on common feeding scenarios, and the yields and compositions of the gas produced. This study has responded to that need for this field data, and the figures presented here have now been used in a further study to scope out those wider implications for Bangladesh [14]. In that study, surveys were undertaken in one district to determine the number of animals living on rural smallholdings and poultry farms, and the number of cattle markets, and using that information and the figures reported here, it was possible to calculate the maximum total optimal potential biogas energy from these feedstock types could meet the current cooking energy requirements of 30 million people in Bangladesh [14].…”

“…This scenario was reported by Grameen Shakti as being the most common and typical for small AD plant. Approximately 50% of the households of Bangladesh live in family groups which own 1-5 cows, [14] providing towards their daily milk needs. Typically, these cattle wander and feed in the vicinity of the smallholding, and their dung is picked up and carried back to a central location by a household member.…”

“…5 Taken from GS Field Operations Manual [23] 6 Using a Normalising Multiplier of 1.27 to convert February temperature measurements to those for the annual averagesee Section 2.3. 7 Fixed dome 8 Floating dome 9 Taken from [14] Yields and methane content…”