Soluble microbial products

Approximately one-half of the organics removed are oxidized to CO2 and H2O, and one-half synthesized to biomass. Three to 10 percent of the organics removed result in soluble microbial products (SMP). The SMP is significant because it causes aquatic toxicity. 

Soluble electrolytes, ternary soap-water systems and, 22 727 Soluble glass, 22 452 Soluble hydrophilic dyes, 9 190 Soluble microbial products (SMP) in biological wastewater treatment, 25 896. 897... 

C.S. Laspidou, E.R. Bruce, A unified theory for extracellular polymeric substances, soluble microbial products, active and inert biomass, Water Res. 11 (2002) 2711-2720. 

Namkung, E., and B. E. Rittmann. 1986. Soluble microbial products (SMP) formation kinetics by biofilms. Water Resources 20 795-806. 

C. Jarusutthirak, G. Amy, Role of soluble microbial products (SMP) in membrane fouling and flux decline. Environmental Science Technology 2006, 40, 969-91 A. 

Holakoo, L., Nakhla, G., Yanfiil, E.K. Bassi, A.S. (2006) Chelating properties and molecular weight distribution of soluble microbial products from an aerobic membrane bioreactor, ff ter Research, 40, 1531-1538. 

N. Park, B. Kwon, I.S. Kim, J.W. Cho, Biofouling potential of various NF membranes with respect to bacteria and their soluble microbial products (SMP) Characterizations, fiux decline, and transport parameters, J Memb Sci, 258 (2005) 43-54. 

During the separation process, particles may deposit on the membrane surface or in membrane pores, causing the TMP to increase (or flux to decline) and affecting the quality of the water produced (membrane fouling). The nature of the feedwater, concentration and structure of the mixed liquor, and nature and concentration of soluble microbial products (SMPs) are all recognised to influence fouling propensity (Judd, 2011). 

Schematic of key chemical transformations that may occur on the addition of iron-based coagulant to a MBR (Wang and Waite, 2010). Addition of inorganic Fe(lll) salts will result in either precipitation as amorphous ferric oxide (AFO) (reaction b), complexation by soluble microbial products (SMPs) (reaction c) or reduction to Fe(ll) (reaction j). Fe(lll) in both inorganic (as AFO) and SMP-bound forms (as Fe(lll)SMP) may undergo reduction (especially in the low Eh (<-0.2 mV) anoxic region (reactions e, a and j). Any Fe(ll) present may be oxidized (especially in the aerated oxic compartment) (reactions i and f). Fe(ll) may form insoluble precipitates such as ferrous phosphate or vivianite (reaction k). 

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