Table 4.45
Pollution prevention techniques applicable to the electrical and electronic component industry (semiconductor printed wiring board, and cathodes
ray tube subcategory)
Industry
Operations
Process or equipment
modification
Raw material substitution/
elimination
Waste segregation/
separation/
preparation
Recycling
General electrical and electronic industry
General
electroplating
Modification of rinsing
methods to control drag-out
Water conservation through
improved rinsing systems.
Use of drip bars and drain
boards to reduce drag-out
Regeneration of plating bath
by activated carbon
filtration to
remove buildup organic contaminants
Installation of pH controller to
reduce the alkaline and acid
concentrations in tanks
Substitution of cyanide plating
solutions with alkaline zinc,
acid zinc, acid sulfate copper,
alkaline copper, electroless
nickel, etc.
Use of sodium bisulfite and
sulfuric acid for ferrous sulfate
to oxidize chronic acid waste.
Replacing cyanide with
non-cyanide baths
Substitution of non-cyanide for
a sodium cyanide solution used
in copper plating baths
Sending drag-out waste to
another company for waste
exchange
Reuse drag-out waste back
into process tank
General recycling of rinse
water
Sludge slagging to extract and
recycle metals
Removal and recovery of lead
and tin from boards by electrolysis of chemical precipitation
Recovery of dissolved copper
from dray-out rinses
Recovery of chromatic acid
drag-out and recycle it into
chromic acid etch line.
Conversion of sludge to
smelter feed
General
etching
Substitution of sodium
persulfate etchant with hydrogen peroxide/sulfuric acid
Replacement of chlorinated
solvent baths with
nonhazardous products to
reduce and later replace use of
chlorinated solvents
Recovery of copper by electrolytic process
184
O. S. Amuda et al.
Pollution prevention techniques applicable to the electrical and electronic component industry (semiconductor printed wiring board, and cathodes
ray tube subcategory)
Industry
Operations
Process or equipment
modification
Raw material substitution/
elimination
Waste segregation/
separation/
preparation
Recycling
General electrical and electronic industry
General
electroplating
Modification of rinsing
methods to control drag-out
Water conservation through
improved rinsing systems.
Use of drip bars and drain
boards to reduce drag-out
Regeneration of plating bath
by activated carbon
filtration to
remove buildup organic contaminants
Installation of pH controller to
reduce the alkaline and acid
concentrations in tanks
Substitution of cyanide plating
solutions with alkaline zinc,
acid zinc, acid sulfate copper,
alkaline copper, electroless
nickel, etc.
Use of sodium bisulfite and
sulfuric acid for ferrous sulfate
to oxidize chronic acid waste.
Replacing cyanide with
non-cyanide baths
Substitution of non-cyanide for
a sodium cyanide solution used
in copper plating baths
Sending drag-out waste to
another company for waste
exchange
Reuse drag-out waste back
into process tank
General recycling of rinse
water
Sludge slagging to extract and
recycle metals
Removal and recovery of lead
and tin from boards by electrolysis of chemical precipitation
Recovery of dissolved copper
from dray-out rinses
Recovery of chromatic acid
drag-out and recycle it into
chromic acid etch line.
Conversion of sludge to
smelter feed
General
etching
Substitution of sodium
persulfate etchant with hydrogen peroxide/sulfuric acid
Replacement of chlorinated
solvent baths with
nonhazardous products to
reduce and later replace use of
chlorinated solvents
Recovery of copper by electrolytic process
184
O. S. Amuda et al.