Bharat Shrestha" <bharatbabu3@hotmail.com> asked
>Could you please elaborate the process and names of chemicals used against pathogens ?
>1)..Do you think such treatment is necessary for family size bio-gas in
>which latrine effluent is mixed with animal dung in biodigester ?
>2)What are the major factors affecting the efficiency of bio-gas production?
>3) What is relation between efficiency of bio-gas production and fertility of effluent/compost ?

Mr. Shrestha has put forth very important questions. Originally it was planned to carry out test of the biochemical characteristics and treatment of stabilized compost against pathogens. It was not done because of the expiry of the project period.  Chinese had used some chemicals as ovicide to treat the slurry produced from faecal sludge. If I get the name, I will inform immediately. In my opinion, although more than 95% pathogens are killed during anaerobic digestion, from hygienic point of view, it is worth to treat the slurry/compost in case human excreta is used as raw material for methane production.

The major factor affecting the gas productions are:

v Nature of substrate
v C:N ratio
v pH
v Temperature
v Loading rate
v Retention period
v Dilutio
v etc

I will answer Mr. Shrestha 3 question  soon.

Best regards to you and Mr. Shrestha

Amrit & Upendra