Passive treatment of acid mine drainage using coal combustion by-products and spent mushroom substrate: Results of column study

Conference · Thu Dec 31 04:00:00 EST 1998

OSTI ID:361693

Crisp, T E; Nairn, R W; Strevett, K A; Everett, J ^[1]

---

1. Univ. of Oklahoma, Norman, OK (United States)

A column study was conducted to evaluate the feasibility of using of coal combustion by-products (CCB) as alkaline materials in a field scale downflow constructed wetlands for acid mine drainage treatment. Five columns (15.24 cm in diameter and 91.44 cm high) were constructed and filled with a combination of spent mushroom substrate (SMS) and one of three alkaline materials (limestone, hydrated fly ash, or fluidized bed ash). The five mixtures utilized were 10% fluidized bed ash/40% limestone (FBA/LS), 10% fluidized bed ash (FBA), 50% limestone (LS), 50% hydrated fly ash (HFA),m and 50% sieved (>1.5 cm) hydrated fly ash (S. HFA) with the remainder as SMS on a w/w basis. Column received synthetic acid mine drainage containing: 400 mg/L iron, 59 mg/L aluminum, 11 mg/L manganese, 50% mg/L magnesium, 40 mg/L calcium, and 1200 mg/L sulfate for 5 months. Anoxic conditions in the influent reservoirs were maintained by a positive nitrogen pressure head. Flow rates of 2.0 mL/minute to each column were maintained by a multichannel peristaltic pump. For all columns, effluent acidity concentrations were less than influent acidity concentration (877{sup {minus}}30, n = 75f). Mean effluent acidity concentrations were 241 mg/L (FBA/LS), 186 mg/L (FBA), 419 mg/L (LS), {minus}28.5 mg/L (HFA), and 351 mg/L (S. HFA), respectively. While all column produced measurable alkalinity, only the HFA column produced a net alkaline discharge. The results of these column studies are applicable to the design and sizing of innovative field scale systems using alkaline-rich CCB`s.

• OSTI ID: 361693
• Report Number(s): CONF-9805185--
• Country of Publication: United States
• Language: English

Related Subjects

01 COAL, LIGNITE, AND PEAT
32 ENERGY CONSERVATION, CONSUMPTION, AND UTILIZATION
ACID MINE DRAINAGE
ACID NEUTRALIZING CAPACITY
ASHES
FLY ASH
INDUSTRIAL WASTES
LIMESTONE
MUSHROOMS
PERFORMANCE
WASTE PRODUCT UTILIZATION
WATER TREATMENT
WETLANDS