19 Evaluation and Optimization of the Treatment Scheme …
199
as an intermediate product for the production of ultimate paint and other products at
an amount of 6500 ton/year.
The treatment requirement defined for the plant was limited with the “Indirect
Discharge Criteria of Industrial Wastewaters” before being discharged to the current
common wastewater treatment plant located in the district. The treatment scheme of
the plant should provide an effluent quality having no harmful effect on the common
wastewater treatment plant.
19.2.2 Wastewater Characteristics
The predominant wastewaters sourced by the plant were categorized in four
different types: Water-based paint wastewater and alkyd resin wastewater as process
wastewaters; cooling water and domestic wastewater.
The production scheme of water-based paint included first the mixing of the
pigments with resins, oils, surfactants and water in a dispersion tank and then the
coloring with colorant. The capacity of water-based paint production was 60 ton/day.
The amount of wastewater was approximately accounted for 6.5 m
3 /day generated
intermittently from cleaning of the reactors at a unit production rate of 0.11 m
3 /ton
water-based paint.
The production of alkyd resin was realized by esterification of polyhydric alcohol,
unsaturated aliphatic acids and polybasic acids. The process produced a wastewater
of 0.035 m
3 per ton alkyd resin amounting intermittently a total of 1.5 m
3 /day.
Cooling system used in the plant was a closed flux generator wasting intermittently an amount of wastewater for 3 m
3 daily. Domestic wastewater sourced by
250 employees was theoretically calculated as 14 m
3 /day by considering a personal
consumption of 56 L/cap.day. Four wastewater sources resulted in a total amount of
25 m
3 /day.
A long-term conventional characterization of 45 days was conducted on process
wastewaters and cooling water to outline the difference in characteristics. The experiments were run on composite samples collected from day-time shift. The average
values on different parameters were shown in Table 19.1 together with the flowrates.
The process wastewaters were tested for only COD, TSS and oil-grease.
The characteristics were then evaluated in a way to treat the effluents with similar
characteristics separately. A most striking result in characterization was appeared
as the strong characteristic of alkyd resin wastewater in terms of COD. The same
property was also reflected by water-based paint wastewaters for TSS and oil-grease
parameters.
199
as an intermediate product for the production of ultimate paint and other products at
an amount of 6500 ton/year.
The treatment requirement defined for the plant was limited with the “Indirect
Discharge Criteria of Industrial Wastewaters” before being discharged to the current
common wastewater treatment plant located in the district. The treatment scheme of
the plant should provide an effluent quality having no harmful effect on the common
wastewater treatment plant.
19.2.2 Wastewater Characteristics
The predominant wastewaters sourced by the plant were categorized in four
different types: Water-based paint wastewater and alkyd resin wastewater as process
wastewaters; cooling water and domestic wastewater.
The production scheme of water-based paint included first the mixing of the
pigments with resins, oils, surfactants and water in a dispersion tank and then the
coloring with colorant. The capacity of water-based paint production was 60 ton/day.
The amount of wastewater was approximately accounted for 6.5 m
3 /day generated
intermittently from cleaning of the reactors at a unit production rate of 0.11 m
3 /ton
water-based paint.
The production of alkyd resin was realized by esterification of polyhydric alcohol,
unsaturated aliphatic acids and polybasic acids. The process produced a wastewater
of 0.035 m
3 per ton alkyd resin amounting intermittently a total of 1.5 m
3 /day.
Cooling system used in the plant was a closed flux generator wasting intermittently an amount of wastewater for 3 m
3 daily. Domestic wastewater sourced by
250 employees was theoretically calculated as 14 m
3 /day by considering a personal
consumption of 56 L/cap.day. Four wastewater sources resulted in a total amount of
25 m
3 /day.
A long-term conventional characterization of 45 days was conducted on process
wastewaters and cooling water to outline the difference in characteristics. The experiments were run on composite samples collected from day-time shift. The average
values on different parameters were shown in Table 19.1 together with the flowrates.
The process wastewaters were tested for only COD, TSS and oil-grease.
The characteristics were then evaluated in a way to treat the effluents with similar
characteristics separately. A most striking result in characterization was appeared
as the strong characteristic of alkyd resin wastewater in terms of COD. The same
property was also reflected by water-based paint wastewaters for TSS and oil-grease
parameters.