Conclusion - Water and sanitation Sanitation KnO 100493_Using biogas technology to solve disposal issues of latrine waste

Using biogas technology to solve the disposal issues surrounding latrine waste

Practical Action

Conclusion

The feasibility of Biogas as a disposal solution has been analysed throughout this report by

examining the technological, economic and social issues regarding its implementation, but it

is clear to see the areas compliment each other. The research has highlighted a number of

issues that any implementing organisation will have to face with a number of solutions

proposed.

A combination of both shallower pits and permanent suction pipes could be beneficial to

solving fluidity/emptying issues and soiling up in pits, but also provide hygiene benefits to the

emptier and fresher feedstock for the digester. The research suggests that haulage issues

depend on time, not distance and therefore time benefit calculations would be required to

ensure placement is economically feasible for the emptying contractor and customer. The

critical factor when assessing digester placement is space, because without it there will be no

other problems. Regarding pressure issues, the use of a storage vessel is proposed rather than

just a comprehensive maintenance program because it provides the user with the ability to

alter the pressure, however further assessment would be required.

Social and cultural constraints are very context specific; however, the importance of keeping

the public fully informed for acceptability has been identified. Financial incentive is very

powerful, therefore outlining the monetary benefit to program participants of increased

emptying frequency will help smooth the change as well as ease social stigmas surrounding

emptying contractors. Increasing the frequency of emptying has also been shown to decrease

risk which is beneficial for both emptier and customer. The necessity of education

programmes has been outlined with example tasks at each stage in; however, once again every

programme will be context specific so a generic model would be hard to construct.

The addition of by-products provides a benefit to the FSM system which closes the loop and

makes it more sustainable. The research has conveyed that by altering the flow of money the

implementer can incentivise correct practice. However, research has highlighted the

interaction between customer and emptying contractor to be weak, and therefore proposes to

divert funds around this stage. A piloting scheme would be required to model the solution.

Regarding management it is proposed that each stage in the process be the responsibility of

an independent stakeholder but an overseeing organisation is provided to help regulate and

manage transactions between parties. This way it promotes competition within each stage but

retains the important element of teamwork.

Collaboration with a local water company is suggested as a solution for initial investment as

well as its benefit as a management party in the organisational structure. The critical factor

when assessing willingness to pay is making the use applicable to the community however,

this must be done in conjunction with addressing acceptability of the gas. Again this is very

context specific therefore collaboration with the community will be required.