AUTO­MAT­ED PROCESS CON­TROL FOR BIO­GAS PLANTS

For effi­cient bio­gas pro­duc­tion, sludge bac­te­ria require a pH-val­ue in the range of about 6.5 to 8. A sta­bi­liza­tion of the pH-val­ue in this area is main­ly achieved (> 85) by the bicar­bon­ate (= buffer sub­stance) released in large quan­ti­ties dur­ing anaer­o­bic degra­da­tion.

Process dis­tur­bances reg­u­lar­ly lead to increased lev­els of free fat­ty acids (FFA) or decreas­ing bicar­bon­ate lev­els, as the acids con­sume bicar­bon­ate. How­ev­er, due to the bufferi­ing effect of the bicar­bon­ate the pH-val­ue is ini­tial­ly hard­ly reduced.

Only when the dis­tur­bance lasts for a long time and the stock of bicar­bon­ate is large­ly exhaust­ed, it comes to a rapid drop in pH-val­ue and sub­se­quent­ly to a reduc­tion or in extreme cas­es to a fail­ure of bio­gas pro­duc­tion.

ADVAN­TAGES OF A PROCESS CON­TROL WITH THE BICAR­BON­ATE ANA­LYZ­ER

• By ful­ly auto­mat­ic mon­i­tor­ing of the bicar­bon­ate con­tent with the BA42 Process Mon­i­tor, process dis­tur­bances can be detect­ed sig­nif­i­cant­ly ear­li­er than with the sole pH-val­ue con­trol. There is more time to avert eco­nom­ic loss­es.
• The high den­si­ty of data of the auto­mat­ic mea­sure­ment allows a tight time assign­ment to changed oper­at­ing con­di­tions. The often dif­fi­cult deter­mi­na­tion of caus­es for process dis­tur­bances is much eas­i­er in this way.
• Auto­mat­ed mea­sure­ment enables 24/7 remote mon­i­tor­ing of biol­o­gy.
• The BA42 mea­sure­ment tech­nol­o­gy thus increas­es the over­all avail­abil­i­ty of bio­gas plants and thus their eco­nom­ic suc­cess.