Increasing sludge-digester efficiency

Journal Article · Mon Jul 17 04:00:00 EDT 1978 · Chem. Eng. (N.Y.); (United States)

OSTI ID:5163625

Barber, N R; Dale, C W

The use of sodium bicarbonate instead of conventional nonbuffering chemicals, such as lime, soda ash, caustic soda, or ammonia, for pH control in aerobic wastewater treatment systems prevents alkali overdosing that can halt bacterial growth and cause corrosion and scale buildup; it also eliminates environmental and health hazards associated with the use of ammonia. In anaerobic systems, which are more energy efficient due to production of methane (used for in-plant heating) but harder to control, the use of lime may cause partial vacuum in tanks, resulting in contamination of the bacteria by atmospheric oxygen sucked into the tank and thus, in explosion; bicarbonate eliminates these problems. Pilot-plant experiments showed that a minimum concentration of 2500 mg/l. alkalinity should be ensured in anaerobic digesters, that each additional gram per liter of NaHCO/sub 3/ up to 5 g/l. can increase methane production by 500 Btu/lb/day, that NaHCO/sub 3/ improves sludge compaction by acting as a coagulant and optimizes pH for peroxide oxidation of H/sub 2/S for odor control and for chlorination of nitrogenous materials. Despite its higher price, NaHCO/sub 3/ can be more economical than lime at plants with wastewater flows below 5 million gal/day and those with low pH wastes.

• Research Organization: Church and Dwight Co.
• OSTI ID: 5163625
• Journal Information: Chem. Eng. (N.Y.); (United States), Journal Name: Chem. Eng. (N.Y.); (United States) Vol. 85:16; ISSN CHEEA
• Country of Publication: United States
• Language: English

Related Subjects

09 BIOMASS FUELS
090122* -- Hydrocarbon Fuels-- Preparation from Wastes or Biomass-- (1976-1989)
140504 -- Solar Energy Conversion-- Biomass Production & Conversion-- (-1989)
AEROBIC DIGESTION
ALKALI METAL COMPOUNDS
ALKANES
ANAEROBIC DIGESTION
BIOCONVERSION
CARBON COMPOUNDS
CARBONATES
DIGESTION
FUNCTIONAL MODELS
HYDROCARBONS
HYDROGEN COMPOUNDS
LIQUID WASTES
MANAGEMENT
METHANE
ORGANIC COMPOUNDS
OXYGEN COMPOUNDS
PH VALUE
PILOT PLANTS
PROCESSING
PRODUCTION
SLUDGES
SODIUM CARBONATES
SODIUM COMPOUNDS
USES
WASTE MANAGEMENT
WASTE PROCESSING
WASTE WATER
WASTES
WATER