@article{fdi:010073751,
  title = {{S}trategy to identify the causes and to solve a sludge granulation problem in methanogenic reactors : application to a full-scale plant treating cheese wastewater},
  author = {{M}acarie, {H}erv{\'e} and {E}squivel, {M}. and {L}aguna, {A}. and {B}aron, {O}. and {E}l {M}amouni, {R}. and {G}uiot, {S}. {R}. and {M}onroy, {O}.},
  editor = {},
  language = {{ENG}},
  abstract = {{G}ranulation of biomass is at the basis of the operation of the most successful anaerobic systems ({UASB}, {EGSB} and {IC} reactors) applied worldwide for wastewater treatment. {D}espite of decades of studies of the biomass granulation process, it is still not fully understood and controlled. "{D}egranulation/lack of granulation" is a problem that occurs sometimes in anaerobic systems resulting often in heavy loss of biomass and poor treatment efficiencies or even complete reactor failure. {S}uch a problem occurred in {M}exico in two full-scale {UASB} reactors treating cheese wastewater. {A} close follow-up of the plant was performed to try to identify the factors responsible for the phenomenon. {B}asically, the list of possible causes to a granulation problem that were investigated can be classified amongst nutritional, i.e. related to wastewater composition (e.g. deficiency or excess of macronutrients or micronutrients, too high {COD} proportion due to proteins or volatile fatty acids, high ammonium, sulphate or fat concentrations), operational (excessive loading rate, sub- or over-optimal water upflow velocity) and structural (poor hydraulic design of the plant). {D}espite of an intensive search, the causes of the granulation problems could not be identified. {T}he present case remains however an example of the strategy that must be followed to identify these causes and could be used as a guide for plant operators or consultants who are confronted with a similar situation independently of the type of wastewater. {A}ccording to a large literature based on successful experiments at lab scale, an attempt to artificially granulate the industrial reactor biomass through the dosage of a cationic polymer was also tested but equally failed. {I}nstead of promoting granulation, the dosage caused a heavy sludge flotation. {T}his shows that the scaling of such a procedure from lab to real scale cannot be advised right away unless its operability at such a scale can be demonstrated.},
  keywords = {{A}naerobic ; {C}ationic polymers ; {C}heese wastewater ; {G}ranulation ; {UASB} ; reactor ; {W}ater upflow velocity ; {T}race metals},
  booktitle = {},
  journal = {{E}nvironmental {S}cience and {P}ollution {R}esearch},
  volume = {25},
  numero = {22},
  pages = {21318--21331},
  ISSN = {0944-1344},
  year = {2018},
  DOI = {10.1007/s11356-017-9818-3},
  URL = {https://www.documentation.ird.fr/hor/fdi:010073751},
}