oil-grease, TSS, and color removal, respectively, while treatment efficiency for total
COD, BOD 5 , oil-grease, TSS, and color removal was 97%, 97.4%, 99.27%, 91%,
and 48.2% for sunflower oil refining wastewater. It is clear from the findings that the
concentrations of all wastewater pollutants parameters were decreased at all levels of
the treatment plant. The study data reveals that the degree of chemical treatment
itself is not efficient enough for the removal of such pollutants. For this reason,
performing only chemical treatment for edible oil refining wastewater is not enough;
the treatment system must be considered in conjunction with biological treatment.
The wastewater treatment plant of the factory operates very efficiently and it is a
good model for the treatment of vegetable edible oil refinery wastewaters. However,
since the MLSS concentration of wastewaters discharged from the plant is higher
than the discharge limits, it is necessary to re-operate sand filter.
Glossary [81–83]
Aerobic An environmental condition in which free and dissolved oxygen is available in an aqueous environment (for instance, nitrification is an aerobic process).
Anaerobic (a) An environmental condition in which free, dissolved, and combined
oxygen is unavailable in an aqueous environment (i.e., dissolved oxygen ¼ 0 mg/
L). (b) A condition in which atmospheric or dissolved molecular oxygen is NOT
present in the aquatic (water) environment.
Coagulation (a) The clumping together of very fine particles into large particles
(floc) caused by the use of chemicals (coagulants). (b) A process of destabilizing
charges of suspended and colloidal particles in water by adding chemicals
(coagulants). In coagulation process, positively charged chemicals are added to
neutralize or destabilize these negative charges and allow the neutralized particles
to accumulate and be removed by clarification (flotation or sedimentation) and/or
filtration.
Dissolved air flotation (DAF) (a) A method of solids separation, whereby a side
stream is saturated with air at high pressure and then injected into the flotation
tank to mix with the incoming water stream. As the air bubbles rise to the surface,
they attach to floc particles and create a sludge layer at the surface of the tank,
which is then removed for disposal. (b) One of the dissolved gas flotation (DGF)
processes when air is used for generation of gas bubbles. A typical example is
Krofta Engineering Corporation’s Supracell clarifier; see dissolved gas flotation
(DGF).
Dissolved gas flotation (DGF) It is a process involving pressurization of gas at
25–95 psig for dissolving gas into water and subsequent release of pressure
(to 1 atm) under laminar flow hydraulic conditions for generating extremely
fine gas bubbles (20–80 microns) which become attached to the impurities to
be removed and rise to the water surface together. The impurities or pollutants to
be removed that are on the water surface are called float or scum which are
scooped off by sludge collection means. The clarified water is discharged from
8 Vegetable Oil Refining Wastes
369
COD, BOD 5 , oil-grease, TSS, and color removal was 97%, 97.4%, 99.27%, 91%,
and 48.2% for sunflower oil refining wastewater. It is clear from the findings that the
concentrations of all wastewater pollutants parameters were decreased at all levels of
the treatment plant. The study data reveals that the degree of chemical treatment
itself is not efficient enough for the removal of such pollutants. For this reason,
performing only chemical treatment for edible oil refining wastewater is not enough;
the treatment system must be considered in conjunction with biological treatment.
The wastewater treatment plant of the factory operates very efficiently and it is a
good model for the treatment of vegetable edible oil refinery wastewaters. However,
since the MLSS concentration of wastewaters discharged from the plant is higher
than the discharge limits, it is necessary to re-operate sand filter.
Glossary [81–83]
Aerobic An environmental condition in which free and dissolved oxygen is available in an aqueous environment (for instance, nitrification is an aerobic process).
Anaerobic (a) An environmental condition in which free, dissolved, and combined
oxygen is unavailable in an aqueous environment (i.e., dissolved oxygen ¼ 0 mg/
L). (b) A condition in which atmospheric or dissolved molecular oxygen is NOT
present in the aquatic (water) environment.
Coagulation (a) The clumping together of very fine particles into large particles
(floc) caused by the use of chemicals (coagulants). (b) A process of destabilizing
charges of suspended and colloidal particles in water by adding chemicals
(coagulants). In coagulation process, positively charged chemicals are added to
neutralize or destabilize these negative charges and allow the neutralized particles
to accumulate and be removed by clarification (flotation or sedimentation) and/or
filtration.
Dissolved air flotation (DAF) (a) A method of solids separation, whereby a side
stream is saturated with air at high pressure and then injected into the flotation
tank to mix with the incoming water stream. As the air bubbles rise to the surface,
they attach to floc particles and create a sludge layer at the surface of the tank,
which is then removed for disposal. (b) One of the dissolved gas flotation (DGF)
processes when air is used for generation of gas bubbles. A typical example is
Krofta Engineering Corporation’s Supracell clarifier; see dissolved gas flotation
(DGF).
Dissolved gas flotation (DGF) It is a process involving pressurization of gas at
25–95 psig for dissolving gas into water and subsequent release of pressure
(to 1 atm) under laminar flow hydraulic conditions for generating extremely
fine gas bubbles (20–80 microns) which become attached to the impurities to
be removed and rise to the water surface together. The impurities or pollutants to
be removed that are on the water surface are called float or scum which are
scooped off by sludge collection means. The clarified water is discharged from
8 Vegetable Oil Refining Wastes
369