Tannery effluent as a carbon source for biological sulphate reduction.
Tannery effluent was assessed as a carbon source for biological sulphate reduction in a pilot-scale upflow anaerobic sludge blanket (UASB), stirred tank reactor (STR) and trench reactor (TR). Sulphate removals of between 60-80% were obtained in all three reactors at total sulphate feed levels of up to 1800 mg l(-1). Sulphate removal in the TR (400-500 mg SO4 l(-1) day(-1)) and UASB (up to 600 mg SO4 l(-1) day(-1)) were higher than those obtained in the STR (250 mg SO4 l(1) day(-1)). A change in operation mode from a UASB to a STR had a large impact on chemical oxygen demand (COD) removal efficiencies. COD removal rates decreased by 25% from 600-700 mg COD l(-1) day(-1) to 200-600 mg COD l(-1) day(-1). The TR had an average COD removal rate of 500 mg COD l(-1) day(-1). Large quantities of sulphide were produced in the reactors (up to 1500 mg l(-1)). However due to the elevated pH in the reactor, only a small amount was in the form of H2S and thus the odour problem normally associated with biological sulphate reduction was not present.
Boshoff
G
G
Environmental Engineering Research Centre, School of Civil Engineering, Queens University Belfast, David Keir Building, Stranmillis Road, Northern Ireland BT9 5AG, UK. g.boshoff@qub.ac.uk
Duncan
J
J
Rose
P D
PD
D019149:Bioreactors; D002244:Carbon / Q000737:chemistry*; D006863:Hydrogen-Ion Concentration; D007220:Industrial Waste; D008906:Mining; D010084:Oxidation-Reduction; D013431:Sulfates / Q000737:chemistry / Q000378:metabolism*; D016999:Sulfur-Reducing Bacteria; D013633:Tanning; D018508:Water Purification / Q000379:methods*
D007220:Industrial Waste; D013431:Sulfates; D002244:Carbon