Dear List, Yesterday I was visiting a handful of "problem" digesters to help get them back on track. The issues is almost always acidity due to overloading (either stemming from too much waste, not enough water, or dropping temperatures), and a big dilution, some bicarbonate, and a new "seeding" from another nearby system is almost always the fix.
However, yesterday I went to a system that had a pH of 7.2 (in the range of OK), but was producing almost no gas. I checked everything before I decided to check the pH of the irrigation water from a deep well they used with the waste. It had a pH of 8.6. That was the most alkaline reading I had seen in input water, which must indicate it is highly mineralized. This pH seems out of a healthy range for AD, but there is no other water source. So, two questions: 1. Please confirm that input water with such high alkalinity could be inhibiting the AD process, and; 2. What could be done to cost effectively (eg no cost) lower the alkalinity, or at least the impact on the AD process. I had them start using less water, arriving at the lowest possible dilution levels for the cow manure, hoping that less water would mean less inhibition of the process. Thought? Best -- Alexander Eaton Sistema Biobolsa IRRI-Mexico RedBioLAC Mex cel: (55) 11522786 US cel: 970 275 4505 [email protected] [email protected] sistemabiobolsa.com www.irrimexico.org www.redbiolac.org
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