WO2018134851A1

WO2018134851A1 - Process for treating industrial effluents

Info

Publication number: WO2018134851A1
Application number: PCT/IN2018/050034
Authority: WO
Inventors: Arvind Mallinath Lali; Hitesh Suresh PAWAR
Original assignee: Individual
Current assignee: Individual
Priority date: 2017-01-20
Filing date: 2018-01-22
Publication date: 2018-07-26
Anticipated expiration: 2019-07-20

Abstract

Present invention relates to an efficient process for treating an effluent generated from industry comprising multiple steps carried out in one or other sequence or combinations thereof to produce clean water with zero liquid discharge. The process described herein, comprises steps of adsorptive separation, anaerobic digestion and/or membrane filtration and finally polishing by using micro filtration or ultra-filtration or nanofiltration or reverse osmosis or combination thereof. The process provides significant reduction of COD, BOD, TDS, colour and odour of effluent thereby generating clean water which can be used for agriculture, domestic and industrial purposes. The recovered organic compounds may be used as energy rich feedstock for generation of energy, fuel and value addition applications etc.

Description

Process for treating industrial effluents

FIELD OF INVENTION

[0001] The present invention relates to an economically viable process for treating an effluent generated from industry to obtain clean water. More particularly, it relates to the process for reducing chemical oxygen demand (COD), biological oxygen demand (BOD), total dissolved solids (TDS), colour and odour from effluent obtained from industry to produce clean water and recovering pollutant for value addition.

BACKGROUND OF THE INVENTION

[0002] India is the fourth largest ethanol producing country after Brazil, the United States and China. Major production of ethanol in distilleries in India is in the form of potable and industrial alcohol. The majority of distilleries use molasses as a feed-stock for ethanol fermentation while some of them employ grains as a feed-stock. Also, the Indian government has set a mandate of 5% ethanol blending in petrol. Presently, the 5% blending of ethanol is applicable only in 10 States and three Union Territories which requires about 410 million litres of anhydrous alcohol. If the 5% of petrol is made mandatory all over the country, the available molasses may be unable to meet the demand of ethanol. The significant increments in both percent blending and widespread requirement is anticipated in near future. There are 325 molasses based distilleries in the country producing 3,063 million litres/year (M.Ltre/year) of alcohol with generation of 45,945 million litre/year (M. Ltr/year) of spent wash as industrial waste water. This spent wash or effluent is largely composed of several hazardous and recalcitrant chemical components generated during the distillation process. Thus, the molasses based distilleries are classified as a 'Red' category industry by the Central Pollution Control Board. Therefore, treatment of distillery waste is a major requirement for the development of green distilleries for future.

[0003] The ethanol is produced by molasses fermentation in batch, continuous or bio still processes in molasses based distilleries. Thus, the distillery effluent majorly contains spent wash produced after the fermentation process of molasses. It was reported that an average spent wash of 10-15 liter/liter of ethanol was produced in molasses based distilleries, having a significantly high chemical oxygen demand (COD) in the range 50,000 to 1,30,000 gm/Lit. Thus, the spent wash discharge without treatment has a highly deleterious effect on human as well as aquatic life cycle due to following factors: (a) it contains significant amounts of recalcitrant compounds which severely pollute the receiving bodies such as rivers, lakes etc and create a serious health hazard; (b) it is also a source of greenhouse gases such as C02, methane and nitrous oxide; (c) it has been found to have strong obnoxious odour which is a major socio-envionmental concern. Thus, the distillery industry has been regarded as one of the most environmentally unfriendly industries. However, development of technology for treatment of distillery spent wash is an emergent need of this industry.

[0004] The distillery spent wash is a dark brown colour liquid with an obnoxious odour. The presence of dark brown colour is due to formation of several polymeric compounds, whereas the odour is due to presence of skatole, indole etc. compounds. The melanoidins and caramels are the major polymeric colorant present in distillery spent wash, formed due to the Millard reaction between sugars and amino acids. The dark brown colour of spent wash is due to presence of these colorant compounds.

[0005] Moreover the effluent water generated from the textile and dye industries is also a major issue and challenge in front of technocrats, because textile and dyes industries are also one of the most water consuming industries. These sectors generate substantial amount of effluent which contains significantly toxic and hazardous chemical compounds such as colorants, metals, metal salts, organic bulk as well as small molecules, halogenated compounds etc. Presently conventional effluent treatment systems are in practise to remove the toxic substances but due to their limitations these methods are not very efficient from the economic and environmental point of view.

[0006] WO2017001712 discloses a process for removing organic dyes from industrial effluent by employing the catalytic hydrogenation method. This invention has achieved significant colour removal but the use of hydrogen at bulk scale in not a preferred option for effluent treatment. Catalytic reduction reduces colour due to reduction reaction but the COD of effluent is still not reduced significantly thus it need further treatment to reduce the COD. The use of expensive noble-metal catalyst is another drawback of said process.

[0007] Existing prior arts also discloses a process for treating liquid effluent from textile and dyes industries by employing ion exchange adsorption process. This invention achieved significant reduction in colour of effluent but the employment of ion exchange adsorbent can only remove the colour components which are ionic in nature. In spite of this for the desorption of ionic components it needs ionic mobile phase which contains alkali or alkaline metal salts which again increase the TDS of effluent. The another major drawback of ion exchange adsorption technique is adsorption cannot go beyond the ion exchange capacity of adsorbent thus the amount of adsorbent required in huge quantity.

[0008] Thus several attempts have been made to remove these colorants by employing chemical and biochemical treatment methods. The chemical degradation and decolourization of colorant from spent wash by using flocculation and physicochemical treatment such as ozonation and activated carbon adsorption have been made (Agric. Biol. Chem.1985, 49, 785-792). Whereas the biological decolourization method by using fungi such as Coriolus, Aspergillus, Phanerochaete and certain bacterial species such as Bacillus, Alkaligenes and Lactobacillus have also reported (Biores. Technol. 2006, 7, 2096-2102; Microbios, 1997, 89, 81-90; Agric. Biol. Chem. 1987, 52, 3339-3346; Agric. Biol. Chem. 1985, 49, 2041-2045). But these methods of colorant removal were not very successful in removal of the entire carbon load from spent wash. In addition, these methods are not economically feasible due to their higher process cost.

[0009] An integrated approach was also made by employing several methods such as; electrocoagulation, physical separation, chemical treatment, ozonation, membrane separation, evaporation and anaerobic digestion. Of these possible processes presently anaerobic digestion is the most commonly used process to treat the sugar industry waste water. The resulting biogas produced from anaerobic digestion is used to generate the heat or power that can supplement the energy requirement of the sugar industry itself. But the present processes including anaerobic digestion (AD) for treating the sugar industry waste water does not provide complete COD or BOD (biological oxygen demand) removal. Thus, the complete COD reduction by AD is also difficult because all carbon in the spent wash is not digested by methanogens. This effluent from AD may also be subjected to aerobic treatment to reduce its BOD but still the colour, COD, suspended solids (SS) and dissolved solids (DS) of the effluent is too high to meet the regulatory standards of quality required for discharge of industrial effluent.

[0010] The direct evaporation by employing energy efficient evaporator technologies such as multiple effect evaporator and agitated thin film dryer has also been investigated. However, since the volume of effluent generated is in huge quantities, the evaporation of water in such bulk quantity is not an economic unit operation. Thus, an evaporator-based approach has not been widely accepted due to its cost and susceptibility to corrosion and scaling problems.

[0011] US6613559 discloses a process for treatment of molasses spent wash by simultaneous decolourization and detoxification method with employment of white root lignin modifying fungus strain Flavodon flavus. The biological treatment method described in this invention is time consuming and required several chemicals for maintaining the culture solution which can be contribut to increased processing cost.

[0012] US20130341267 describes a process and apparatus for treating spent wash and other waste water. The said invention includes the use of one or more of anaerobic digestion, chemical treatment, electrocoagulation, aerobic treatment, physical separation and reverse osmosis (RO) or adsorbent based treatment. The adsorbent used in this process are activated carbon, polyvinyl chloride or cellulose acetate phthalate, most preferably bagasse. The integration of multiple unit operations increases the process complexity as well process cost. Thus, the techno-commercial implementation of such process faces several financial and economic barriers.

[0013] WO 2012077124 discloses co-processing method for treatment of spent wash in a cement plant. The said invention employed concentration of spent wash by water evaporation and then incineration into cement kiln or thermal power plant or sponge furnace. The combination of evaporation and incineration is not a techno-commercially feasible unit operation due to stringent operating conditions. Additionally, incineration may be considered as an environmentally harmful practice. [0014] US6589427 discloses a process for treating spent wash and black liquor by flocculation and ion exchange adsorption. The said process used flocculating agent consisting of a mixture of salts of Group (III) transition metals, mixture of natural earth's along with oxide of alkaline earth metal and strong acid macroporous cation exchange resin having styrene matrix with sulphite as functional group. The requirement of metal salts as flocculating agent for bulk feed is huge and their treatment after use is also a challenge. Moreover, the regeneration of cation exchange resin generates salts which may increase the salt concentration in water.

[0015] Thus in order to meet the environmental quality guidelines and pollution control board regulations a number of primary and secondary treatment process have been installed for treatment of distillery waste water. These entire methods remove reasonably good percentage of COD, BOD, colour, toxicity and inorganic impurities but are still unable to generate clean and competent water with zero liquid discharge. Thus, such partially treated effluents from distillery industries are not allowed to mix in the natural stream.

[0016] To overcome above mentioned drawbacks and in order to meet an environmental quality guidelines and pollution control board regulations, there is a need to develop techno-economically viable and environmentally friendly process for treatment of effluent generated from industry to produce clean water.

OBJECTIVES OF THE INVENTION

[0017] The principle object of the present invention is to provide a techno- economically viable and environmentally friendly process for the treating liquid industrial effluent to produce clean water and recovering organic compounds as pollutant for value addition.

[0018] Another object of present invention is to provide a process for significant reduction of Chemical Oxygen Demand (COD), Biological Oxygen demand (BOD), Total Dissolved Solid (TDS), colour and odour of the effluent obtained from industry such as distilleries or sugar industries in order to meet environmental quality guidelines and pollution control board regulations. [0019] Yet another object of present invention is to provide an integrated process for treating effluent obtained from industry to generate clean water with zero liquid discharge.

[0020] It is still further object of the invention is to provide a process for removal of organic compounds from effluent obtained from industry which can be used as feedstock for generation of energy or fuel.

[0021] Another object of the invention is to provide a process for generation of clean water from liquid industrial effluent and said generated clean water can be used for agricultural, domestic and industrial purposes.

SUMMARY OF THE INVENTION

[0022] One of the aspects of present invention provides an efficient process for treating an effluent generated from industry comprising of following multiple steps carried out in one or other sequence or combinations thereof:

a) contacting a effluent with a solid support material in a suitable contactor for a desired contact time to remove at least 10% by weight with respect to the effluent of a matter selected from the group consisting of organic matter, inorganic matter, and combinations thereof to obtain a treated stream;

b) subjecting the treated stream from step (a) to anaerobic digestion (AD) to produce biogas and to obtain a first processed stream; and

c) polishing the first processed stream from step (b) to obtain clean water, wherein the clean water has COD less than 300 ppm and BOD less than 30 ppm.

[0023] Another aspect of present invention provides an integrated process for removal of COD, BOD, TDS, colour and odour of liquid industry effluents. The said process involves use of polystyrene divinyl benzene based hydrophobic resin for removal of at least 10% of organic and/or inorganic compound and then resulting treated stream with reduced COD and BOD is subjected to anaerobic digestion or membrane separation to generate clean water for reuse. The resulting organic compound removed from solid support material and membrane process can be used as energy rich feedstock for generation of energy, fuel and value addition applications etc. The obtained clean water can be used for parent process in distillery industry or for any industrial, agricultural or domestic purposes. DETAILED DESCRIPTION OF THE INVENTION

[0024] In the present invention, different terms are used for describing the invention. The definitions of some of the terms are as follows:

[0025] The term "liquid industrial effluent/s or effluent water or "effluent" used herein refers to liquid effluent generated from industry such as but not limited to sugar industry, pulp and paper industry, textile industry, cement industry, chemical industry, food industry, leather industry, industrial laundry wastewater etc. The effluent generated from industry may involve such as but not limited to spent wash, vinasse, stillage, reflux condensate, multiple effective evaporator condensate, evaporator blowdowns, wash water, molasses residues, molasses spent wash, black liquor, etc. and mixture thereof. The said effluent may have dark brown colour or maybe containing any colored impurities. The industrial effluent may be essentially transparent containing non-colored toxic impurities. The terms "liquid industrial effluent" or "effluent water" or "effluent" or "spent wash" can be used interchangeably in the specification. For the purposes of the invention, the term 'stream' can refer to any process flow step selected from the group consisting of flow through, treated stream, first processed stream, clarified stream, second processed stream, and combinations thereof. In another embodiment of the present disclosure the process maybe a batch process, wherein the output of the various process steps is considered as the 'stream'. For the purposes of the invention the terms 'flow through' and 'treated stream' have been used interchangeably.

[0026] For the purposes of the present invention the term BOD or biological oxygen demand may be defined as the amount of dissolved oxygen needed (i.e. demanded) by aerobic biological organisms to break down organic material present in a given water sample at certain temperature over a specific time period. Hence, greater the BOD, more polluted the water sample.

[0027] For the purposes of the present invention the term COD or the chemical oxygen demand is defined as the measure of the capacity of water to consume oxygen during the decomposition of organic matter and the oxidation of inorganic chemicals such as Ammonia and nitrite. Hence, greater the COD, more polluted the water sample. [0028] The term "clean water" used herein refers to clean water obtained after treatment of industrial effluent by present invention or technology which passes all the tests of minimum permissible limits set by pollution control board for the use in industrial or domestic applications or discharge to natural resources. For the purposes of the present disclosure, clean water refers to water with the following specification: a) having no colored impurities; b) no foul odor; c) COD less than 300 ppm; and d) BOD less than 30 ppm.

[0029] The term "contactor" used herein refers to any type of tank or reactor or column used for contacting the solid support material with liquid effluent stream in suitable manner.

[0030] The terms "organic compounds" or "organic matter" used herein refers to compounds already present in the liquid effluent generated from industry. Organic compounds are major pollutant in industrial effluents. Said organic compounds comprises sugars, carbohydrates, short chain fatty acids, long chain fatty acids, phenols, melanoidins, caramels, wax compounds, alcohols, aromatics, hydrocarbons etc. The term "organic compounds" and "organic matter" can be used interchangeably in the specification. The term "inorganic matter" refers to ammonia, nitrates nitrites, sulphates, phosphates and other contaminants well known to the person skilled in the art.

[0031] Hereinafter, embodiments of the present invention described in detailed as follows. It should be understood that many variations and medications of the basic inventive concept herein described, which may appear to those skilled in the art, will still fall within the spirit and scope of the present invention as defined in the appended embodiments.

[0032] The present invention aims to establish an efficient, non-complex, techno- economically viable and eco-friendly process for the treatment of effluent water produced from sugar industry or distillery spent wash or wash water or molasses spent wash. Thus, the present invention provides an integrated process for removal of COD, BOD, TDS, colour and odour of effluent. The integration and use of non-complex and energy efficient unit operation significantly reduces energy, processing cost without any use of expensive, hazardous chemicals and chemical reagents. [0033] In an embodiment of the present disclosure, there is provided an integrated process for treating an industrial effluent comprising: a) contacting an effluent with a solid support material in a suitable contactor for a desired contact time to remove at least 10% by weight with respect to the effluent of a matter selected from the group consisting of organic matter, inorganic matter, and combinations thereof to obtain a treated stream; b) subjecting the treated stream from step (a) to anaerobic digestion (AD) to produce biogas and to obtain a first processed stream; and c) polishing first processed stream from step (b) to obtain clean water, wherein clean water has COD less than 300 ppm and BOD less than 30 ppm.

[0034] In an embodiment of the present disclosure, there is provided an integrated process for treating an industrial effluent comprising: a) contacting an effluent with a solid support material in a suitable contactor for a desired contact time to remove at least 10% by weight with respect to the effluent of a matter selected from the group consisting of organic matter, inorganic matter, and combinations thereof to obtain a treated stream; b) subjecting the treated stream from step (a) to anaerobic digestion (AD) to produce biogas and to obtain a first processed stream; c) clarifying the stream selected from the group consisting of treated stream from step (a), the first processed stream from step (b), and combinations thereof to obtain a clarified stream; and d) polishing the first processed stream obtained from step (b), and combinations thereof to obtain clean water, wherein clean water has COD less than 300 ppm and BOD less than 30 ppm

[0035] In an embodiment of the present disclosure, there is provided an integrated process for treating an industrial effluent comprising: a) contacting an effluent with a solid support material in a suitable contactor for a desired contact time to remove at least 10% by weight with respect to the effluent of a matter selected from the group consisting of organic matter, inorganic matter, and combinations thereof to obtain a treated stream; b) subjecting the treated stream from step (a) to anaerobic digestion (AD) to produce biogas and to obtain a first processed stream; c) clarifying the stream selected from the group consisting of treated stream from step (a), the first processed stream from step (b), and combinations thereof to obtain a clarified stream; d) optionally, contacting the clarified stream from step (c) with a solid support material in suitable contactor to produce a second processed stream; and e) polishing a stream selected from the group consisting of clarified stream from step (c), second processed stream obtained from step (d), and combinations thereof to obtain clean water, wherein clean water has COD less than 300 ppm and BOD less than 30 ppm.

[0036] One of embodiments of present invention provides an efficient process for treating an effluent generated from industry comprising following multiple steps carried out in one or other sequence or combinations thereof, wherein said process comprises:

a) contacting the effluent with a solid support material in a suitable contactor to remove significant amount of organic compounds to obtain a flow through or treated stream; wherein flow through or treated stream obtained has reduced COD in the range of 50,000 ppm to 55,000 ppm and BOD in the range of 10,000 to 30,000 ppm;

b) subjecting the flow through or treated stream from step (a) to anaerobic digestion (AD) to produce biogas and effluent with further reduced COD in the range of 5000 ppm to 20000 ppm and BOD in the range of 1000 to 15000 ppm;

c) subjecting the flow (flow through or effluent or treated stream) obtained from earlier step (a) or (b) to clarification step and contacting clarified effluent with another solid support material in suitable contactor to produce a stream with further reduced COD<300 ppm and BOD in the range of< 30 ppm;

d) polishing the stream obtained from the step (c) by subjecting it to a combination of micro filtration (MF) or Ultra filtration (UF) or nanofiltration (NF) or reverse osmosis (RO) to produce clean water; and e) eluting or desorbing the bound organic compounds from solid support material used resulting in reuse of solid support material and producing recovered organic compounds for appropriate value added or utilisation.

[0037] In another embodiment of the present invention there is provided a process for treating an effluent generated from industry, wherein said effluent generated from industry such as but not limited to sugar industry, textile industry, cement industry, chemical industry, leather industry, food industry, Industrial laundry wastewater. [0038] In another embodiment of present invention there is provided a process for treating an effluent generated from industry, wherein said effluent may be selected from the group but not limited to spent wash, wash water, molasses residues, molasses spent wash, black liquor, etc. and mixture thereof. The said effluent may have dark brown colour or containing any colorant impurities or non-colored impurities.

[0039] In another embodiment of present invention there is provided a process for treating liquid industrial effluent to obtain clean water, wherein the liquid industrial effluent has COD in the range of 10 gm/L to 200 gm/L and having any colour from clear to dark brown with odour or odourless.

[0040] Another embodiment of present invention provides a process for treating liquid industrial effluent to obtain clean water, wherein Total Dissolved Solid (TDS) in the effluent is in the range of 2% to 20%.

[0041] Another embodiment of present invention provides a process for treating liquid industrial effluent to obtain clean water, wherein the Total Suspended Solids (TSS) in the effluent is in the range of 0% to 20%. In another embodiment of the present disclosure, the TSS in the effluent is in the range of 0.1% to 20%.

[0042] Another embodiment of present invention there is provided a process for treating liquid industrial effluent to obtain clean water, wherein pH of effluent is in the range of 1 to 14 and conductivity is in the range of 10 to 100 mS/s.

[0043] Yet another embodiment of present invention provides a process for treating liquid industrial effluent to obtain clear water, wherein the effluent may contain diverse concentration of organic compounds or organic matter such as but not limited to sugars, carbohydrates, short chain fatty acids, long chain fatty acids, phenols, melanoidins, caramels, wax compounds, alcohols, aromatics, hydrocarbons etc.

[0044] Another embodiment of present invention provides a process for treating liquid industrial effluent to obtain clean water, wherein significant amount of organic compounds from effluent is removed by contacting the effluent with a solid support material in a suitable contactor for the suitable time period. The flow through or treated stream obtained after removal of organic compound has reduced chemical oxygen demand (COD) in the range of 50,000 ppm to 55,000 ppm. In said process at least 10% organic compound may be removed by adsorptive separation, more preferably at least 50% organic compounds may be removed.

[0045] In another embodiment of present invention there is provided a process for treating effluent generated from industry to produce clean water, wherein said process is carried out by contacting liquid industrial effluent with solid support material for the time period of 1 min to 60 min with the desire flow rate. During this process organic matter get bound or adsorbed on the solid support material and flow through or treated stream obtained with reduced COD and BOD. The bed volume of solid support material used for said process is in the range of 2 to 50 bed volumes and adjusted as per requirement of removal of COD. In another embodiment of the present disclosure, the desired contact time is in the range of 1 min to 60 min. In yet another embodiment of the present disclosure the process as described herein, wherein the desired contact time is 1 min to 30 min. In yet another embodiment of the present disclosure the process as described herein, wherein the desired contact time is 2 min to 10 min. In yet another embodiment of the present disclosure the process as described herein, wherein the desired contact time is 2 min to 8 min.

[0046] In another embodiment of present invention there is provides a process for treating liquid industrial effluent to produce clean water, wherein the said removal of organic compounds may be performed in batch or continuous condition in packed or fluidised column to obtain at least 10% removal of organic compounds or colorants or inorganic matter. In another embodiment of the present disclosure the process as described herein, wherein contacting the effluent with the solid support material in a suitable contactor for a desired contact time to remove at least 10% organic and inorganic matter.

[0047] Another embodiment of present invention provides a process for treating liquid industrial effluent to produce clean water, wherein solid support material comprises adsorbent. In another embodiment of the present disclosure the process as described herein, wherein the support material comprises adsorbent. The said solid support material or adsorbent used for adsorptive separation process is selected from the group but not limited to polystyrene divinylbenzene based hydrophobic resin. In another embodiment of the present disclosure, the solid support used for contacting an effluent in step (a) and contacting the clarified stream in step (c) is independently selected from the group consisting of polystyrene divinylbenzene based hydrophobic resin.

[0048] Another embodiment of present invention provides a process for treating effluent generated from industry to produce clean water, wherein the said solid support material used for adsorptive separation of organic compounds is in the form of but not limited to micro/macro porous spherical beads or in powder form.

[0049] Another embodiment of present invention provides a process for treating liquid industrial effluent to obtain clean water, wherein the said solid support material may have polymeric back-bone of polystyrene, modified polystyrene, polystyrene divinylbenzene, modified polystyrene divinylbenzene, or any alkyl, aryl, hydroxy, halogen, amine derivative of modified polystyrene.

[0050] Yet another embodiment of present invention provides a process for treating effluent generated from industry to produce clean water, wherein the treated stream obtained after removal of organic compounds is subjected to anaerobic digestion (AD) to produce biogas and a first processed stream with further reduced COD in the range of 5000 ppm to 20,000 ppm and BOD in the range of 1000 to 15000 ppm.

[0051] In most preferred embodiment of present invention there is provided a process for treating effluent generated from industry to obtain clean water, wherein anaerobic digestion is carried out in digester such as but not limited to Up-flow Anaerobic Sludge Blanket (UASB), Expanded Granular Sludge Blanket (EGSB), Hybrid Up- flow Anaerobic Sludge Blanket (HUASB), Plug Flow Reactors (PFR) Anaerobic Fixed Bed Reactor (AFBR), Continuous Stirred Tank Reactor (CSTR) etc. In another embodiment of the present disclosure, there is provided a process as described herein, wherein the anaerobic digestion (AD) is carried out by any conventional method known to a person skilled in the art.

[0052] Another embodiment of present invention there is provided a process for treating effluent generated from industry to obtain clean water, wherein yield of biogas produced is at least 80% of its theoretical yield.

[0053] In another embodiment of present invention there is provided a process for treating effluent generated from industry to obtain clean water, wherein treated stream or effluent obtained from earlier step (a) or (b) respectively is subjected to clarification step to obtain clarified effluent. The clarified effluent is then contacted with the solid support material in suitable contactor to produce a second processed stream with further reduced COD in the range of 100 ppm to 300 ppm and BOD less than 50 ppm.

[0054] Another embodiment of present invention provides a process for treating liquid industrial effluent to obtain clean water, wherein said polishing is carried out by membrane separation. In another embodiment of the present disclosure, said membrane separation may selected from group such as but not limited to micro filtration (MF), nano filtration (NF), reverse osmosis (RO), and combinations thereof.

[0055] In an embodiment of the present disclosure the process as described herein, wherein said process further comprises eluting and recovering the bound organic compounds from the solid support material to obtain recovered organic compounds. In another embodiment of present invention there is provides a process for treating effluent generated from industry to obtain clean water, wherein the said solid support material used for adsorptive separation may be regenerated or eluted or desorbed by using organic solvent or water or mixture thereof, wherein said solvent comprises alcohols such as but not limited to methanol, ethanol, propanol, butanol etc.; esters such as but not limited to ethyl acetate, butyl acetate, etc.; ethers such as but not limited to diethyl ether, dimethyl ether etc., ketones such as such as but not limited to acetone, methyl ethyl ketone, methyl isobutyl ketone etc.; nitrile such as but not limited to acetonitrile etc.

[0056] Yet another embodiment of present invention provides a process for treating effluent generated from industry to produce clean water, wherein generation or activation of said solid support material may be carried out at a pH in the range of 1 to 14. The acidic pH is obtained by using acid such as but not limited to organic or mineral acids, and basic pH is obtained by using base or alkali such as but not limited to alkali or alkaline metal hydroxides.

[0057] In one embodiment, the present invention provides a process for treating effluent generated from industry to produce clear water, wherein organic compounds obtained after eluting or desorbing from solid support material can be used as feedstock for generation energy and fuels or for the generation of value added chemicals or products etc. [0058] Yet another embodiment of present invention provides a process for treating effluent generated from industry to obtain clear water, wherein the treated stream obtained after contacting effluent with solid support material may be subjected to anaerobic digestion or membrane separation to produce clean water.

[0059] In still another embodiment of present invention there is provided a process for treating liquid industrial effluent to produce clear water, wherein the stream with reduced COD obtained from the final step (c) is polished by subjecting it to micro filtration (MF) or Ultra filtration (UF) or nanofiltration (NF) or reverse osmosis (RO) to produce clean water. The MF, UF, NF, RO may be used either singly or in combinations thereof.

[0060] Another embodiment of the present invention provides a process for treating liquid industrial effluent to produce clean water, wherein said process may be carried out in one or more steps such as but not limited to filtration, particle removal, centrifugal separation etc.

[0061] Another embodiment of present invention provides a process for treating effluent generated from industry to produce clean water, wherein said process can be used for treatment of effluent generated from industry such as but not limited to dyes, textile, paint, fine chemical, biochemical, bulk chemical, pharmaceutical, flavour, petrochemical industries etc.

[0062] In an embodiment of present disclosure there provided a process as described herein, wherein said contactor is selected from tank, reactor, column, and combinations thereof.

[0063] In an embodiment of present disclosure there provided a process as described herein, wherein the process provides a reduction in COD in the range of 99.1-99.9% with respect to the COD in the treated stream and a reduction in BOD in the range of 99.2-99.9% with respect to the COD in the treated stream. In another embodiment of the present disclosure there is provided a process, wherein the process provides a reduction in COD in the range of 99.2-99.7% with respect to the COD in the treated stream and a reduction in BOD in the range of 99.3- 99.8% with respect to the COD in the treated stream.

EXAMPLES [0064] The invention is further illustrated by working examples as detailed below. The examples are meant for illustrative purposes only and are not meant imply restriction to the scope of the disclosure in any manner. Example 1

[0065] The adsorptive separation of organic compounds was conducted in packed bed glass column having a dimension (L x D) is 100 cm X 5 cm. The 800 ml of polystyrene divinyl benzene based hydrophobic resin was linearly packed through column without any air channel. After packing of adsorbent the resin bed was washed by 1 to 2 bed volume of water and a desire flow rate was adjusted to get contact time 5 min. Around 10 lit of spent wash having COD- 1,00,000 to 1, 10,000 ppm were passed through the bed and resulting flow-through fraction was collected. The COD analysis of flow-through fraction showed COD contain 50,000 to 55,000 ppm. The resulting flow-through fraction was subjected to NF followed by RO membrane and resulting permeate was collected and analysed for COD and TDS contain which showed COD 200 ppm and TDS 300 ppm with clear and odourless behaviour. The permeate water was also tested in detail for competency of water for industrial and domestic use and it showed the resulting water passed from the test according to norms.

Example 2

[0066] The adsorptive separation of organic or inorganic carbon was conducted in packed bed glass column having a dimension (L x D) is 100 cm X 5 cm. The 800 ml of polystyrene divinyl benzene based hydrophobic resin was linearly packed through column without any air channel. After packing of adsorbent the resin bed was washed by 1 to 2 bed volume of water and a desire flow rate was adjusted to get contact time 5 min. Around 10 lit of spent wash having COD- 1,00,000 to 1,10,000 ppm were passed through the bed and resulting flow-through fraction was collected. The COD analysis of flow-through fraction showed COD-50,000 to 55,000 ppm. The resulting flow-through fraction was subjected to anaerobic digestion and resulting biodigesters outlet was collated which showed COD contain 5,000 to 20,000 ppm. Then this biodigesters outlet was subjected to NF membrane and resulting permeate was collected and analysed for COD and TDS contain which showed COD 200 ppm and TDS 300 ppm with clear and odourless behaviour. The permeate water was also tested in detail for competency of water for industrial and domestic use and it showed the resulting water passed from the test according to norms.

Example 3

[0067] The adsorptive separation of organic or inorganic carbon was conducted in packed bed glass column having a dimension (L X D) is 100 cm X 5 cm. The 800 ml of polystyrene divinyl benzene based hydrophobic resin was linearly packed through column without any air channel. After packing of adsorbent the resin bed was washed by 1 to 2 bed volume of water and a desire flow rate was adjusted to get contact time 2 min. Around 10 lit of spent wash having COD- 1,00,000 to 1, 10,000ppm were passed through the bed and resulting flow-through fraction was collected. The COD analysis of flow-through fraction showed COD contain 50,000 to 55,000 ppm. The resulting flow-through fraction was subjected to anaerobic digestion and resulting biodigesters outlet was collated which showed COD contain 5,000-20,000ppm. Then this biodigesters outlet was subjected to NF membrane and resulting permeate was collected and analysed for COD and TDS contain which showed COD 200 ppm and TDS 300 ppm with clear and odourless behaviour. The permeate water was also tested in detail for competency of water.

Example 4

[0068] The adsorptive separation of organic or inorganic carbon was conducted in packed bed glass column having a dimension (L x D) is 100 cm X 5 cm. The 800 ml of polystyrene divinyl benzene based hydrophobic resin was linearly packed through column without any air channel. After packing of adsorbent the resin bed was washed by 1 to 2 bed volume of water and a desire flow rate was adjusted to get contact time 5 min. Around 10 lit of spent wash having COD of 1,10,000 ppm was passed through the bed and resulting flow-through fraction was collected. The COD analysis of flow-through fraction showed COD contain 55,000 ppm. The resulting flow-through fraction was subjected to anaerobic digestion and resulting biodigesters outlet was collated which showed COD contain 20,000 ppm. Then this biodigesters outlet was subjected to NF membrane and resulting permeate was collected and analysed for COD and TDS contain which showed COD 210 ppm and TDS 350 ppm with clear and odourless behaviour. The permeate water was also tested in detail for competency of water for industrial and domestic use and it showed the resulting water passed from the test according to norms.

Example 5

[0069] The adsorptive separation of organic or inorganic carbon was conducted in packed bed glass column having a dimension (L X D) is 100 cm X 5 cm. The 800 ml of polystyrene divinyl benzene based hydrophobic resin was linearly packed through column without any air channel. After packing of adsorbent the resin bed was washed by 1-2 bed volume of water and a desire flow rate was adjusted to get contact time 5 min. Around 10 lit of effluent from dyes industry having COD of l,05,000ppm was passed through the bed and resulting flow-through fraction was collected. The COD analysis of flow-through fraction showed COD contain 55,000ppm. The resulting flow-through fraction was subjected to anaerobic digestion and resulting biodigesters outlet was collated which showed COD contain 20,000ppm. Then this biodigesters outlet was subjected to NF membrane and resulting permeate was collected and analysed for COD and TDS contain which showed COD 210 PPM and TDS 350ppm with clear and odourless behaviour. The permeate water was also tested in detail for competency of water for industrial and domestic use and it showed the resulting water passed from the test according to norms.

Example 6

[0070] The adsorptive separation of organic compounds was conducted in packed bed glass column having a dimension (L x D) is 100 cm X 5 cm. The 800 ml of polystyrene divinyl benzene based hydrophobic resin was linearly packed through column without any air channel. After packing of adsorbent the resin bed was washed by 1 to 2 bed volume of water and a desire flow rate was adjusted to get contact time 20 min. Around 10 lit of spent wash having COD- 1,00,000 to 1, 10,000 ppm were passed through the bed and resulting flow-through fraction was collected. The COD analysis of flow-through fraction showed COD contain 45,000 to 50,000 ppm. The resulting flow-through fraction was subjected to NF followed by RO membrane and resulting permeate was collected and analysed for COD and TDS contain which showed COD 200 ppm and TDS 300 ppm with clear and odourless behaviour. The permeate water was also tested in detail for competency of water for industrial and domestic use and it showed the resulting water passed from the test according to norms.

Example 7

[0071] The adsorptive separation of organic compounds was conducted in packed bed glass column having a dimension (L x D) is 100 cm X 5 cm. The 800 ml of polystyrene divinyl benzene based hydrophobic resin was linearly packed through column without any air channel. After packing of adsorbent the resin bed was washed by 1 to 2 bed volume of water and a desire flow rate was adjusted to get contact time 60 min. Around 10 lit of spent wash having COD- 1,00,000 to 1, 10,000 ppm were passed through the bed and resulting flow-through fraction was collected. The COD analysis of flow-through fraction showed COD contain 40,000 to 45,000 ppm. The resulting flow-through fraction was subjected to NF followed by RO membrane and resulting permeate was collected and analysed for COD and TDS contain which showed COD 200 ppm and TDS 300 ppm with clear and odourless behaviour. The permeate water was also tested in detail for competency of water for industrial and domestic use and it showed the resulting water passed from the test according to norms.

Claims

I/We claim:

1. An integrated process for treating an industrial effluent comprising: a) contacting an effluent with a solid support material in a suitable contactor for a desired contact time to remove at least 10% by weight with respect to the effluent of a matter selected from the group consisting of organic matter, inorganic matter, and combinations thereof to obtain a treated stream; b) subjecting the treated stream from step (a) to anaerobic digestion (AD) to produce biogas and to obtain a first processed stream; and c) polishing first processed stream from step (b to obtain clean water, wherein the clean water has COD less than 300 ppm and BOD less than 30 ppm.

2. The process as claimed in claim 1, wherein the solid support material comprises adsorbent.

3. The process as claimed in claim 2, wherein the adsorbent is polystyrene divinylbenzene based hydrophobic resin.

4. The process as claimed in claim 1, wherein said contactor is selected from tank, reactor, column, and combinations thereof.

5. The process as claimed in claim 1, wherein the desired contact time is in the range of 1 min to 60 min.

6. The process as claimed in claim 1, wherein clarifying and polishing is carried out by a process selected from the group consisting of micro filtration (MF), ultra filtration (UF), nanofiltration (NF), reverse osmosis (RO), and combinations thereof.

7. The process as claimed in claim 1, wherein said process further comprises eluting and recovering the bound organic compounds from the solid support material to obtain recovered organic compounds.

8. The process as claimed in claim 1, wherein the treated stream is having COD in the range of 50,000 ppm to 55,000 ppm and BOD in the range of 10,000 to 30,000 ppm.

9. The process as claimed in claim 1, wherein the first processed stream is having COD in the range of 5000 ppm to 20000 ppm and BOD in the range of 1000 to 15000 ppm.

10. The process as claimed in claims 1 and 8, wherein the process provides a reduction in COD in the range of 99.1-99.7% with respect to the COD in the treated stream and a reduction in BOD in the range of 99.2-99.9% with respect to the COD in the treated stream.

11. The process as claimed in claim 1, wherein the process further comprises clarifying the stream selected from the group consisting of treated stream from step (a), the first processed stream from step (b), and combinations thereof to obtain a clarified stream.

12. The process as claimed in claim 11, wherein the process optionally

comprises contacting the clarified stream with a solid support material in suitable contactor to produce a second processed stream; and

13. An integrated process for treating an industrial effluent comprising: a) contacting an effluent with a solid support material in a suitable contactor for a desired contact time to remove at least 10% by weight with respect to the effluent of a matter selected from the group consisting of organic matter, inorganic matter, and combinations thereof to obtain a treated stream; b) subjecting the treated stream from step (a) to anaerobic digestion (AD) to produce biogas and to obtain a first processed stream; c) clarifying a stream selected from the group consisting of treated stream from step (a), the first processed stream from step (b), and combinations thereof to obtain a clarified stream; d) optionally, contacting the clarified stream from step (c) with a solid support material in suitable contactor to produce a second processed stream; and e) polishing a stream selected from the group consisting of clarified stream from step (c), second processed stream obtained from step

(d), and combinations thereof to obtain clean water, wherein the clean water has COD less than 300 ppm and BOD less than 30 ppm.