Title of Invention

A PROCESS FOR THE TREATMENT OF WASTE PETROLEUM OIL FOR OBTAINING REFINED PETROLEUM OIL THEREFROM

Abstract This invention relates to a process for the treatment of waste petroleum oil for obtaining refined petroleum oil therefrom. Waste oil (such as waste lubricating oil and other contaminated or degraded petroleum oil waste). The method comprises hydrocarbons having a commercial use if it can be treated to restore its commercial qualities. The present invention introduces dehydrated waste petroleum oil into the upper portion of the bottom section of a distillation column, recirculating the said oil by discharging the same oil from the lower portion of the bottom section of the column and reintroducing the same into the said upper portion, while separating and removing the various fractions from the recirculating oil as vapour. The interior of the column is maintained between 700 mm Hg and 760 mm Hg.
Full Text This invention retates to a process for the treatment of waste petroleum oil for obtaining refined petroleum oil therefrom.
Waste petroleum oil, such as, waste subricating oil and other contaminated or degraded petroleum oil waste is classified as hazardous waste all over the world and has the potential to pollute water supply and soil, causing pollution to drinking water as wel1 as threat to msirine life and I and vegetation.
Waste oil comprises hydrocarbons having a commercial use if It can be treated to restore its commercial qualities .
Presently, in India, waste oil treatment is done by a process called acid clay treatment.
Thi s process involves the dehydration of the waste oil by distilling the water therefrom in a dehydrator; the dehydrated oil is heated and then cooled to ambient temperature (this step is called thermal cracking); the waste oil from the thermal cracker is then mixed with sulphuric acid

and left for settling. The acid sludge is decanted and disposed of. The clear oil is transferred to the clay treatment section.
In the clay treatment section, the oil is mixed with activated alumina clay and the mixture is heated and subjected to distillation under vacuum. The oil clay mixture is filtered in a press and the clear oil is now sent for commercial use.
The effluent in the above known procees, apart
from water, are the acid sludge (around 20% to
50 % of the waste oils processed) and spent clay,
the quantity of which is also substantial. The
life of the plant used in this process is low due
to heavy corroeion by the use of acid.
Additionally, the plant emits flue gas and other
gases including SO

Another known process does not use sulphuric acid.
The waste oil is treated with chemicals to
coagulate the degraded additives: carbon, s1udge
and other impurities. These are filtered out and
the remaining oil is then eubiected to act i vated
alumina clay treatment and vacuum distillation.

In this process, the use of chemicals will essentially generate solid waste which will be d i ff icult. to d i spose of. The actual separation of undesirable, degraded or other foreign matters is done by the uss of chemicalE, absorbent or adsorbent. The eff1uont f rom the process are water, coagulant along with carbon, spent additives, sludge and other impurities, and spent clay in addition to emissions of flue and process gases. A major drawback with this process is the high cost of operation of the plant.
The equipment used in the above two processes are distillation columns with standard types of trays such as bubb1e-cap trays, si eve trays, valve trays etc. or packed column. The use of these types of trays is possible because the oil has been f reed from degraded add i ti ves, carbon and many other impuri ties which might otherwise clog the trays. In other words, the waste oil has to be subj ected to chemical processes and physical separation before fractionation. As a I ready stated, these types of processes will generate effluents that are difficult to diepose of in an envi ronmenta1 iy

safe manner.
This invention therefore proposes a process for the treatment of waste petroleum oil for obtaining refined petroleum oil therefrom eliminating or, at least, greatly minimising the abovementioned drawbacks aseociated with the known procegses of treating waste petroleum oil.
The process, according to this invention, for the
treatment of waste petroleum oil for obtaining
refined petroleum oil therefrom, comprises
introducing dehydrated waste petroleum oil into
the upper portion of the bottom section of a
distillation column recirculating the said oil
by discharging the same oil from the lower portion
of the bottom section of the column and reĀ¬
introducing the same into the said upper portion,
while separating and removing, as vapour, the
various fractions from the recirculatlng oil;
maintaining the interior of the column between 700
mm Hg. to 760 mm Hg. vacuum; heating the
recirculating oil so as to maintain the
temperature thereof within the
bottom section of the column between 300 deg. C

360 deg. C: allowing the vapours of the heated recirculating oil to ascend upwardly through a plurality of chambers, disposed over the bottom section of the column, one above the other, and through trays separating the chambers, each tray having a free passage surmounted by a hood, the passages in the said trays, allowing vapours, rising from the hot oil in the said upper portion, to pass therethrough, and the hoods constraini ng such vapours to condense around the trays in the respective chambers} tapping the condensed oil of varioue grades from such chambers; and spraying cold oil in at least one of such chambers : and ooJlecting the remnsnt vapours f rom the topmost chamber.
This invention will now be descr ibed w i th referenoe to the accompany ing drawings which 11 Iustrate by way of example one of the possible embod itnents of the apparatus empi oyad to carry out the process proposed herein, wherein
Fig. 1 ill ustrates the distil iation column of the said embodiment

Fig,2 illustrates a separate view of the tray used
therein.
The distillation column D has an inlet 11 near its base for the entry of dehydrated waste petroleum oil into the bottom section R of the column at its base.
The dehydrated oil is obtained from a dehydrator after removal of final traces of water and any lighter fractions of hydrocarbons present in the waste oil.
The column D has an opening A at its bottom for allowing the reci rculation of the oil f rom the lower portion of the said bottom section R, through the inlet II, to the said upper portion.
Means, such as, a pump and heater are provided for recirculating and heating the oil and for separating and vapourising the various fractions of oil in the recirculating oil.
Means, such as, a vacuum pump, steam ejectors and

the like are prov ided f or the column for maintain!ng the interior of the column under 700 mm Hg, to 760 mm Hg vacuum pressure.
Means are also provided, for the colurm, for maintaining the temperature of the oil within the bottom section R of the col urnn between 300 deg, C 360 deg, C.
The column housoG a plurality of chambers {in the embod iment il lustrated, five chambers) CI to C5, d isposed one above the other, over the said bottom section R, for receiving the vapours of the hot oil from within the bottom section R, such chambers being separated from each other by trays T, The chambers may be structured as one unit (as illustrated) or as separate modules communicating with each other as convenience may dictate.
Each tray has a free passage P surmounted by a hood H. The passages P in the trays T allow vapours (see arrows B), rising from the hot oil in the bottom section R, to pass freely therethroughr without clogging, while the hoods H constrain portions of such vapours (see arrows EI to condense around the trays in the respecti ve

chambers. The condensate is indicated by F1 to F5. Each condensate is a grade of hydrocarbon oil, the higher the chamber, the lighter the fract i on.
The chambers have outlets Gl to G5 for tapping and remov ing the condensed oil of var ious grades theref rom.
To assist or control the condensation of the oil in the chambers cold oil is sprayed in at 1 east one of the chambers e.g. through a pipe line J provided with perforations or nozzles. This oil is tapped from the condensate in any one of thp chambers C1 to C5.
The column D has an open ing K at the top of the topmost chamber C5 for the ex it, and col1ection, of the remnant vapours therefrom. These vapours are taken to a separate chamber for condensation and collection. This will correspond to the lightest grade of oil. The non-condensible vapour and gas are sucked out by steam ejectors/vacuum pumps and sent for incineration. The column vacuum is maintai ned by thi B system.

The terms and expressions in this specification are of description and not of limitation, there being no intention in the use of such terms and eKpresslons of eKcludlng any equi valente of the features illustrated and described, having regard to the scope and ambit of this invention.


We CI aim:
1.A process for the treatment of waste petroleum oil for obtaining refined petrolsum oil therefrom comprising the steps of introducing dehydrated waste petroleum oil into the upper portion of the bottom section of a distillation column; recirculating the said oil by discharging the same oil from the lower portion of the bottom section of the column and re-introducing the same into the said upper portion, while separating and removing, ae vapour, the various fractions from the recirculating oil; maintaining the interior of the column between 700 mm Hg. to 760 mm Hg. vacuum; heating the recirculating oil eo as to maintain the temperature thereof within the bottom section of the column between 300 deg. C 360 deg. C; allowing the vapours of the heated recirculating oil to ascend upwardly through a plurality of chambers, disposed over the bottom section of the column, one above the other, and through trays separating the chambers, each tray having a free passage surmounted by a hood, the passages in the said trays, allowing vapours.

rising from the hot oil in the said upper portion, to pass therethrough, and the hoods constraining such vapours to condense around the trays in the respective chambers; tapping the condensed oil of various grades from such chambers; and spray i ng cold oil in at least one of such chambers; and col1ecting the remnant vapours from the topmost chamber.
2.A process for the treatment of waste petroleum oil for obtaining refined petroleum oil therefrom substantially as herein described with reference to, and as illustrated by, the accompanying draw ings.
I

Documents:

494-mas-1998 abstract.pdf

494-mas-1998 claims.pdf

494-mas-1998 claism-duplicate.pdf

494-mas-1998 correspondence-others.pdf

494-mas-1998 correspondence-po.pdf

494-mas-1998 description (completed)-duplicate.pdf

494-mas-1998 description (completed).pdf

494-mas-1998 drawings.pdf

494-mas-1998 form-1.pdf

494-mas-1998 form-19.pdf

494-mas-1998 form-26.pdf


Patent Number 200793
Indian Patent Application Number 494/MAS/1998
PG Journal Number 30/2009
Publication Date 24-Jul-2009
Grant Date
Date of Filing 11-Mar-1998
Name of Patentee ORYX ENGINEERING & CONSULTANCY (P) LTD
Applicant Address D-3 T.C. IV/759, "LEKSHMI ", KOWDIAR P.O., TRIVANDRUM 695 003.
Inventors:
# Inventor's Name Inventor's Address
1 CHEERAN VARGHESE KOCHUKUNJAN "CHEERANS", CHITRAPUZHA, P.O. IRIMPANAM THRIPUNITHURA, ERNAKULAM,
PCT International Classification Number N/A
PCT International Application Number N/A
PCT International Filing date
PCT Conventions:
# PCT Application Number Date of Convention Priority Country
1 NA