Feasibility Of Biogas Digesters In Bangladesh Environmental Sciences

Essay add: 11-01-2017, 17:07   /   Views: 14

This feasibility study report has been prepared as per the Memorandum of Understanding (MOU) signed between Grameen Shakti, Bangladesh and PEAR Carbon Offset Initiative Limited, Japan for the implementation of commercial biogas digesters as a Clean Development Mechanism Programme of Activities (CPA) to contribute to the sustainable economic development of Bangladesh.

This CPA to be implemented in Faridpur municipality includes two commercial biogas digesters with total biogas (methane content is around 65%) production capacity of 500 m3/day initially. About 250-300 households of the Faridpur municipality will enjoy gas supply from this plant. The Faridpur municipal authority collects classifies and transports the wastes to the sites of biogas digesters under contracts with Grameen Shakti. And the bioslurry from the biogas digesters is dried before it will be used as organic fertilizer to increase soil fertility and thereby productivity.

Background Information

Energy is one of the most important fundamentals of development. Bangladesh is one of the low energy consuming countries of the world. Here, only 8% people are connected to natural gas supply and 40% could so far be covered with national grid. Out of 22 gas fields discovered so far, 2 are abandoned, 5 are exhausted and the rests are going to be finished in the near future. 85% of the country's electricity is based on natural gas. With the lapse of time the situation is aggravating further as the energy demands are increasing. Searching renewable sources of energy is the only option to meet the ensuing energy crisis. Among the renewable energy technologies (RETs), biogas is considered to be the most suitable for Bangladesh as its raw materials available everywhere cheaply, temperature of Bangladesh is appropriate and technology is locally available and proven.

Grameen Shakti (GS), a non-governmental organization and a sister concern of world famous Grameen Bank, is one of the largest and fastest growing rural based renewable energy facilitator in the world. GS has developed one of the most successful market based program with a social objective for disseminating biogas technology and solar home systems to millions of rural villagers. In order to expand biogas utilization in Bangladesh, Grameen Shakti plans to implement the proposed CDM Programme of Activities (PoA) which promotes plant type commercial biogas digesters in local cities of Bangladesh to supply biogas for thermal usage of targeted households. The PoA will install numerous medium or large size biogas digesters (fixed dome type or soft bag type) which consume municipal organic wastes that are otherwise disposed to landfills where from methane is emitted to atmosphere. It is noted that this series of activities (programme) is the first-of-this-kind in Bangladesh.

Faridpur Municipal Area

The CPA covers "Municipal Area of Faridpur" and its geographical coordinates are 23°36' 36" N - 89° 51' 00" E. The figure below shows the location of Faridpur Municipality Area (yellow boundary line in the map) in Bangladesh. Faridpur Municipality was established in 1869. The Municipal Area consists of 9 wards and 35 mahallas. The area of the Municipal Area is 20.5 [] square km. The population of the Municipal Area is 99634; male 51.73%, female 48.27%. The density of population is 4925 per square km. The literacy rate among the town people is 66.6%. [] 

Figure: Map of Faridpur Sub-district and Faridpur Municipality Area

Site Selection

On 01 March 2011, Grameen Shakti officials visited Faridpur municipal area along with the delegates from PEAR Carbon Offset Initiative Limited and Bureau VERITAS. During the visit, the honorable Mayor of Faridpur municipal area expressed his keen interest about the proposed biogas project and assured to provide all kind of support and cooperation to Grameen Shakti for implementing this project. The Mayor also proposed an existing landfill site and another piece of plain land for the biodigesters. Both sites are just off the main road with very good transportation facilities. Final decision regarding the site selection will be taken upon further discussion with Faridpur Municipal Authority.

Technical & Legal Facts

In the Faridpur Municipality around 90% people are dependent on biomass for everyday cooking as there is no natural gas supply. Moreover, the alternative fuels like kerosene and liquefied petroleum gas (LPG) are expensive for most of the people. A study showed that 4.24 tons fuel-wood were consumed per family per year in Bangladesh [] . That means the proposed project will save around 1,275 tons of biomass every year. Subsequently, the proposed project will reduce the CO2 emission by 3,500 tons approximately every year. There are quite a number of wood shops in the Faridpur municipality area which causes serious deforestation and others environmental problems around the neighborhood.

The Environmental Conservation Rules of Bangladesh has been carefully studied and received the clearance certificate from the Department of Environment regarding this project and the local authority verbally agreed to sign a MOU with Grameen Shakti concerning this project.

Waste Management

The Faridpur municipal area is excluded from the government's waste composting programme which alternatively forced to create un-engineered landfill sites. On the subject of current practice of waste management, municipality collects the wastes from the households and dumps it to the existing landfill sites which causes severe odor nuisance and emits CH4 and other hazardous gases. Moreover, these landfill sites cause visual instruction to the municipality dwellers.

The Faridpur Municipality has already divided the whole area into 64 sub-areas and provided 1 collection van in each sub-area. Their current collection capacity is about 14 tons per day which becomes 20 tons per day at the moment. According to the municipal officials, 75% of the municipal wastes are organic. Therefore, the total amount of the organic waste from the Faridpur Municipality is about 15 tons and only 12 tons would be required to operate the proposed biodigesters. Water requirement for the biodigesters will be provided by the municipally with their existing water supply system.

Community's Perception

Grameen Shakti could not arrange stakeholder consultation meeting due to municipality election at Faridpur. Instead, Dr. Golam Rabbani of Grameen Shakti conducted survey on 20 experts and relevant organizations and 30 male as well as 20 female households at Faridpur

Questions

Answers

Positive impacts or Yes

Negative impacts

No impact

Don't know

No comment

What impacts do you think the project activity will have on the local environment

Improve living conditions of householders nearby landfill, reduce fuel cost, maintained family health (20 person)

Nil

Nil

Nil

Nil

What impacts do you think the project activity will have on employment and social welfare in the local area

Have an employment opportunity, positive impact on social welfare (20 person)

Nil

Nil

Nil

Nil

Are there any negative impacts on your livelihood during the construction of the project? (Please address in the column of negative impacts if there are)

Nil

20 persons

Nil

Nil

Nil

What would be the overall positive effects of the construction and operation of the project? (Please address in the column of positive impacts, if applicable)

Creation of new jobs, Friendly environment, wastes would converted into wealth, organic fertilizer produced, reduce afforestation

(20 person)

Nil

Nil

Nil

Nil

What would be the overall negative effects of the construction and operation of the project? (Please address in the column of negative impacts, if applicable)

Nil

Bad odor could spread, local labour might be affected by different diseases (02 persons)

Nil

Nil

18

persons

What is your attitude towards the construction of the project?

Excellent

20 person

Do you support the project? Please address if you have any questions or comments about the project

Yes, 20 persons.

Some comments from experts are as follows-

1. Source segregation would be done in household level.

2. Wastes would be carried by van.

3. Awareness raising programme would be continued.

4. Wastes should be put into digester with machine.

5. Predigestion might be required. municipal area through questionnaires from Carbon Offset Initiative Limited, Japan. All of them expressed their positive responses to this project.

Table 1: Opinions of 20 Experts on Large Biogas Plant Construction at Faridpur

Table 2: Opinions of 50 Households (30 male &20 female) on proposed biodigesters at Faridpur

Questions

Answers

Positive impacts or

Yes

Negative impacts or No

No impacts

Don't know

No comments

What impacts do you think the project activity will have on the local environment

28 male

+

19 female

Nil

Nil

02 male

+

01 female

Nil

What impacts do you think the project activity will have on employment and social welfare in the local area

21male

+

10 female

Nil male

+

03 female

03 male

+

04 female

Nil male

+

01female

06 male

+

02 female

Are there any negative impacts on your livelihood during the construction of the project? (Please address in the column of negative impacts if there are)

Nil

11 male

+

Nil female

18 male

+

20 female

01male

+

Nil female

Nil

What would be the overall positive effects of the construction and operation of the project? (Please address in the column of positive impacts, if applicable)

30 male

+

20 female

Nil

Nil

Nil

Nil

What would be the overall negative effects of the construction and operation of the project? (Please address in the column of negative impacts, if applicable)

Nil

Nil

26 male

+

20 female

02 male

+

Nil female

02male

+

Nil female

What is your attitude towards the construction of the project?

Excellent

30 male +20 female

Do you support the project? Please address if you have any questions or comments about the project

Yes (30 male +20 female)

Some comments from households are as follows-

1. Source segregation would be done in household level.

2. Wastes would carried by van.

3. Awareness raising programme would be continued.

4. Injected wastes into digester by machine.

5. Predigestion must be needed.

Water Requirements

The river Padma passed through the Faridpur sub-district and there are a number of canals around the municipal area which make the surface water available for the municipality dwellers. The Faridpur Municipal Authority assured Grameen Shakti to provide sufficient water supply for the proposed biodigesters.

Human Resources

Grameen Shakti has established its wide span network throughout the country. In the Faridpur Municipality, Grameen Shakti is operating its business through a Divisional Office, a Regional Office and a Branch Office with sufficient human resources. The Branch Office will operate the proposed biodigesters and the Divisional Office and the Regional Office will supervise the activities of the Branch Office. Grameen Shakti will provide necessary training to the staff for operating the proposed biogas plant.

Potential Benefits

In general, it contributes to affordable energy gas utility service to the households in municipal people who cannot access to natural gas distribution network. The biogas is self-sufficient and renewable energy source which contributes to the energy security of Bangladesh as well. Moreover, biogas could potentially help reduce global climate change. Normally, wastes that are left to decompose releases two main gases that cause global climate change: nitrous dioxide and methane. In addition, the municipality dwellers will get a pleasant life without odours from landfill sites and authority would be able to use the recovered space for some other good purposes.

Through this project, every year more than 1,250 tons of biomass use will be replaced by biogas. As a result, there will be no indoor pollution. House wives will get more time to take care of their kids. There will be pollution free environment as the households organic waste will go into the digester. Improved quality organic fertilizer as bioslurry will be produced. This fertilizer can supplement chemical fertilizers which destroy the soil quality. Bioslurry from the biogas digesters is dried before its use in agricultural lands as soil conditioner.

For social and environmental aspects, the programme mitigates the impacts of biomass reliance included forestation, drudgery of rural women and children tasked with collecting, drying and using biomass and health impacts of indoor air pollution to women and children. Most importantly, the CPA contributes to the sustainable economic development of Bangladesh from various aspects.

Potential Hazards

During the survey, it appeared that interviewees are very concern about the potential odor nuisance from the proposed biodigesters. However, it is evident that biological degradation through fermentation process usually reduces the bad smell of the organic waste up to 80-90%. Moreover, if the proposed biodigesters will install beside the main road it may cause visual intrusion to the city dwellers.

Every morning there would be a possibility of traffic congestion at the site area if all the 64 vans will appear at the same time. However, good management may reduce the potential risk. It would be also a huge challenge for the municipal authority to provide only the organic portion of the municipal waste collected from the households as it requires public acceptance and awareness. Proper awareness program can change the person's habit of gathering all types of waste together. During winter when temperature goes down, the biogas production in the biodigesters will be reduced as well. It will cause some trouble of getting less gas for the potential biogas users.

Conclusion

The CDM project's aim is to provide renewable energy facility to the municipality residents as well as to facilitate a smart solution for municipal solid waste. This CPA will be a bold step against the global climate change and a strong commitment towards the environment conservation which will eventually ensure the sustainable development of Bangladesh. Although this report mentioned some potential hazards concerning this project, appropriate management strategies would solve most of them. In conclusion, this feasibility study found numerous positive indications in favor of the proposed CDM PoA and evidently this project is feasible considering technical, social, legal and environmental aspects.

Article name: Feasibility Of Biogas Digesters In Bangladesh Environmental Sciences essay, research paper, dissertation