Effect of small-scale composting of sewage sludge on heavy metal availability to plants

Journal Article · · J. Environ. Qual.; (United States)

OSTI ID:6598267

Simeoni, K A; Barbarick, K A; Sabey, B R

The effect of small-scale composting of sewage sludge on heavy metal availability to plants was investigated. Sand-bed dried, anaerobically digested sewage sludge was mixed with wood chips in a 1:3 volumetric ratio, placed in a 1.4-m/sup 3/ box, and amended with sucrose as an available C source. The mixture was composted for about 90 d. A greenhouse study was conducted to evaluate the differences in sludge due to composting. Lettuce (Lactuca sativa) and oats (Avena sativa) were grown in pots containing composted and uncomposted sludge additions at rates equivalent to 0, 60, 120, and 240 Mg/ha to an acid Redfeather loamy sand (Lithic Cryoboralfs) and a neutral Nunn Clay loam (Aridic Argiustolls). After 7 weeks, dry-matter yields were measured and soil and plant samples were analyzed for total content of Cd, Cu, and Zn. Determinations were also made of soil pH, electrical conductivity (EC), and cation exchange capacity (CEC). An organic matter fractionation was carried out on both sludges to determine changes in organic matter and metal distribution brought about by composting. Additions of compost produced greater yields of both species than additions of sludge due to the lower soluble salt content and Zn availability of the compost. The higher application rates of compost maintained a higher pH on the loamy sand, which possibly decreased Cd and Zn availability to plants. Leaching of soluble Cu complexed during composting might have contributed to a 49% decrease in sludge Cu content, yet no change was noted in Cu availability to crops. Composting increased the humic acid, decreased the ..beta..-humus, and changed Cu and Cd distribution in sludge organic matter.

• Research Organization: Colorado State Univ., Fort Collins
• OSTI ID: 6598267
• Journal Information: J. Environ. Qual.; (United States), Journal Name: J. Environ. Qual.; (United States) Vol. 13:2; ISSN JEVQA
• Country of Publication: United States
• Language: English

Related Subjects

510200 -- Environment
Terrestrial-- Chemicals Monitoring & Transport-- (-1989)
54 ENVIRONMENTAL SCIENCES
560303* -- Chemicals Metabolism & Toxicology-- Plants-- (-1987)
63 RADIATION, THERMAL, AND OTHER ENVIRON. POLLUTANT EFFECTS ON LIVING ORGS. AND BIOL. MAT.
BIOLOGICAL AVAILABILITY
CADMIUM
CATIONS
CHARGED PARTICLES
COMPOST
COPPER
DISSOLUTION
ELECTRIC CONDUCTIVITY
ELECTRICAL PROPERTIES
ELEMENTS
ENVIRONMENTAL EFFECTS
FRACTIONATION
ION EXCHANGE
IONS
LEACHING
METALS
ORGANIC MATTER
PH VALUE
PHYSICAL PROPERTIES
PLANTS
PRODUCTIVITY
QUANTITY RATIO
SEPARATION PROCESSES
SEWAGE
SEWAGE SLUDGE
SLUDGES
SOILS
TRANSITION ELEMENTS
WASTE PRODUCT UTILIZATION
WASTES
ZINC