A Process for Organic Defilement of Polymers in Industrial
Wastewater
Field of the invention
[0001] The present invention relates generally to the field of industrial wastewater or effluent treatment comprising polymers. More particularly, the present invention relates to a process for organic defilement of textile industry wastewater containing polyvinyl alcohol (PVA) based on bacterial growth amelioration.
Background of the invention
[0002] Industries, such as textile industries, typically produce large volumes of wastewater and effluents having untreatable synthetic polymers, which are soluble in water. One of the most common polymer found in the textile industries wastewater is polyvinyl alcohol (PVA). PVA is a viscous compound and is made up of complex chains of polymers which are difficult to break. PVA is widely used in textile industries for strengthening the yarn, processing the yarn, processing fabric, etc.
[0003] Further, it has been observed that PVA present in the industrial wastewater and effluent is toxic, extremely harmful to the environment and causes environmental pollution, as it is not easily degradable. Further, complex chain of PVA is capable of being degraded by the action of specific microorganisms, such as bacteria and therefore, PVA is biodegradable. However, it has been observed that traditional biodegradation processes used in the biodegradation of PVA present in the wastewater and effluent discharged from the textile industries are not effective and efficient as the biodegradation of complex PVA chains

requires specialized biodegradation conditions, which the traditional processes are unable to provide.
[0004] In light of the aforementioned drawbacks, there is a need for a process for providing efficient and effective biodegradation of PVA present in the industrial wastewater or effluent. Further, there is a need for a process for environment friendly and sustainable textile manufacturing process by complete degradation of PVA complex chains present in the wastewater or effluent.
Summary of the invention
[0005] In various embodiments of the present invention, a process for organic defilement of polymers present in industrial wastewater is provided. The process comprises of mixing a polymer effluent with polymer decomposing microorganisms for biodegradation of the polymeric chain. The temperature of the polymer effluent mixed with the microorganisms is maintained in the range of between 21°C-45°C and a loading rate in the range of between 0.07 to 0.11 kg/kg. Further, retaining the polymer effluent mixed with the microorganisms at a retention rate of at least 30 days. Further, after retention, a treated effluent with sludge is formed.
Brief description of the accompanying drawings
[0006] The present invention is described by way of embodiments illustrated in the accompanying drawings wherein:
[0007] FIG. 1 illustrates a system for carrying out the process for organic defilement of polymers present in industrial wastewater, in accordance with an embodiment of the present invention.

Detailed description of the invention
[0008] The present invention discloses a process for providing efficient and effective biodegradation of polyvinyl alcohol (PVA) present in industrial wastewater or effluent. In particular, the present invention provides for organic degradation or defilement of PVA present in textile industry wastewater or effluent under specific aerobic microbial conditions. The present invention provides for viscosity destruction of the PVA present in the industrial wastewater or effluent based on the polymeric chain destruction of PVA by microbial action.
[0009] The disclosure is provided in order to enable a person having ordinary skill in the art to practice the invention. Exemplary embodiments herein are provided only for illustrative purposes and various modifications will be readily apparent to persons skilled in the art. The general principles defined herein may be applied to other embodiments and applications without departing from the spirit and scope of the invention. The terminology and phraseology used herein is for the purpose of describing exemplary embodiments and should not be considered limiting. Thus, the present invention is to be accorded the widest scope encompassing numerous alternatives, modifications and equivalents consistent with the principles and features disclosed herein. For purposes of clarity, details relating to technical material that is known in the technical fields related to the invention have been briefly described or omitted so as not to unnecessarily obscure the present invention.
[0010] The present invention would now be discussed in context of embodiments as illustrated in the accompanying drawings.

[0011] In an embodiment of the present invention, the polyvinyl alcohol (PVA) compound and its derivatives present in the textile industry wastewater or effluent are degraded based on biological treatment of the wastewater or effluent. The biological treatment of wastewater or effluent is carried out using specific type of microorganism or microbes such as bacteria, fungi, protozoan, etc. which are capable of degrading polymers. The microorganisms used in the invention are available to the public and may be procured from the market. The biological treatment comprising the microorganism or microbes is carried out under specific controlled aerobic microbial conditions.
[0012] FIG. 1 is a block diagram illustrating a primary treatment stage 102 and a secondary treatment stage 104 for carrying out organic defilement of polymers present in industrial wastewater, in accordance with an embodiment of the present invention. The primary treatment stage 102 comprises an effluent collection tank 106, a lifting tank 108 and an equalization tank 110. Further, the secondary treatment stage 104 comprises an aeration tank 112, a stagnation tank 114 and a treated effluent tank 116.
[0013] In an embodiment of the present invention, in operation, the wastewater or effluent discharged from the textile industry comprising PVA is treated in a two stage process for carrying out biodegradation of PVA i.e. the primary treatment stage 102 and the secondary treatment stage 104. In an embodiment of the present invention, the PVA effluent present in the wastewater or effluent discharged from the textile industry is separated and collected in the effluent collection tank 106 of the primary treatment stage 102 via a separate drainage system using a pumping mechanism. The PVA effluent present in the wastewater or effluent discharged from the textile industry is of high temperature, which is in the range of between 90°C to 100°C. The pH of

the PVA effluent is in the range of between 8.5 to 11.5 and viscosity is around 1.68 cP.
[0014] In an embodiment of the present invention, the PVA effluent collected in the effluent collection tank 106 is transferred to the lifting tank 108. The PVA effluent is stored in the lifting tank 108. The lifting tank 108 is used to lift all the effluent containing PVA generated from the textile processing. The lifting tank 110 is located at a lower level with respect to the effluent collection tank 106 and therefore the effluent is lifted and transferred by means of pumps.
[0015] In an embodiment of the present invention, the PVA effluent from the lifting tank 108 is thereafter transferred to the equalization tank 110. The PVA effluent is passed through filters, based on a screening process, present before the equalization tank 110 for effectively removing the fluff present in the PVA effluent. The filters are at least of disc shape with a pore size of 100 microns. Further, subsequent to filtering, the filtered PVA effluent is stored in the equalization tank 110 for further treatment. The equalization tank 110 controls the feed rate of PVA effluent for achieving appropriate biodegradation of the PVA present in the effluent. Further, the equalization tank 110 aids in executing maintenance activities without affecting the textile manufacturing process.
[0016] In an embodiment of the present invention, the filtered PVA effluent from the equalization tank 110 is transferred to the aeration tank 112. The filtered PVA effluent or wastewater which is transferred to the aeration tank 112 is exposed and mixed with specific microorganisms for initiating the biodegradation of the PVA and its derivatives present in the filtered effluent. The aeration tank 112 is a carousal shaped tank having three flow makers

installed beneath the aeration tank 112. The flow makers aids in dragging the effluent in forward direction for effective mixing of effluent with the microorganism. The microorganism or microbes may include, but are not limited to, microsporidia, euglena, rotaliida and sulcozoa. The aeration tank 112 initiates treatment of the PVA effluent and the microorganisms carries out the biodegradation of the PVA present in the effluent under controlled aerobic microbial conditions. The controlled aerobic microbial conditions comprises specific dissolved oxygen (DO) range, specific temperature for microorganisms action, specific retention rate of treated PVA effluent and specific organic loading rate.
[0017] In an embodiment of the present invention, the dissolved oxygen (DO) in the aeration tank 112 is in the range of between 1.5 ppm-2.5 ppm, which augments the biodegradation of the PVA effluent by the microorganisms. The DO is measured with the help of a DO-meter installed in the aeration tank 112. The aeration tank 112 is provided with diffusers at the bottom for supplying air and maintaining the specific DO. In an embodiment of the present invention, the temperature of the aeration tank 112 is maintained in the range of between 21°C-45°C, preferably less than 45°C for enhancing action of the microorganisms. The temperature range is essential for efficient action of the microorganisms as at temperature <20°C and >45°C microorganisms are not able to survive and therefore, effectiveness and efficiency of the biodegradation of effluent becomes difficult.
[0018] In an embodiment of the present invention, the organic loading rate is maintained preferably in the range of between 0.07 to 0.11 kg/kg. The loading rate represents the amount of feed required by the microorganisms present in the aeration tank 112 for efficient biodegradation of PVA.

Further, it was observed, through experimentation, that the said range of loading rate provides efficient biodegradation of PVA present in the effluent by the microorganisms. Therefore, if loading rate decreases or increases beyond the said range, the biodegradation of the PVA present in the effluent decreases. The microorganisms culture present in aeration tank 112 under the said aerobic microbial conditions reproduce up to a pre-determined level and thereafter a feed is fed to the microorganisms for further augmenting the biodegradation of PVA by the microorganisms and an activated sludge is formed. The pollutants chemical oxygen demand (COD)/biochemical oxygen demand (BOD) (COD/BOD) present in the effluent or wastewater acts as the feed for the microorganisms present in the aeration tank 112. It has been observed that, the COD and BOD associated with the organic pollutants is surprisingly reduced due to biodegradation process under the said controlled aerobic microbial conditions in accordance with various embodiments of the present invention.
[0019] In an embodiment of the present invention, the activated sludge comprising the PVA effluent and the microorganisms is retained in the aeration tank 112 preferably at a retention rate of at least 30 days. The retention at the preferred retention rate aids the microorganisms to effectively break the complex polymeric chain of the PVA. Further, after retention, the aeration tank 112 comprises of the treated effluent with sludge. In an embodiment of the present invention, the treated effluent with the sludge from the aeration tank 112 is transferred to the stagnation tank 114 for separation of the treated effluent and the sludge by stagnation process. Further, during stagnation process, the sludge settles down at the bottom of the stagnation tank 114 leaving the treated effluent. The pH of the treated effluent separated from the

sludge is in the range of between 7.0 to 8.5 with a viscosity in the range of between 0.95 cP to 1.1 cP. Further, under the said microbial conditions, activated sludge aids in ineffectively degrading the PVA present in the effluent.
[0020] In an embodiment of the present invention, the treated effluent from the stagnation tank 114 is transferred to the treated effluent tank 116 for further use.
[0021] In an embodiment of the present invention, the sludge from the stagnation tank 114 is recirculated back to the aeration tank 112 using a pumping mechanism at low speed and further subjected to the aerobic microbial conditions for further biodegradation of the PVA. The low speed prevents breaking of sludge flocks. The recirculation of the activated sludge is carried out continuously for maintaining activated sludge volume in the aeration tank 112 in order to provide efficient degradation of the PVA effluent by ensuring adequate feed rate.
[0022] In accordance with various embodiments of the present invention, experiments were performed for determining the effect of the biodegradation process on the PVA effluent when the effluent was provided from an inlet and subsequently collected from an outlet after biodegradation and treatment. The experimental data as illustrated in the table 1 below showed significant degradation of PVA present in the wastewater or effluent.
Table 1

S. No. Parameters Inlet Outlet
Total
1. suspended solids (TSS) 2 0 6ppm lOppm

2. Chemical oxygen demand (COD) 19 60 0ppm lOOppm
3. Polyvinyl alcohol (PVA) 13345ppm 10.3ppm
4. pH 8.7 7.8
[0023] Advantageously, in various embodiments of the present invention, the process of present invention provides for efficient and effective biodegradation of PVA present in the industrial wastewaters and effluents. The process of present invention provides for 99.92% degradation of PVA present in effluent or wastewater. Further, the process of present invention provides for 99.5% degradation of COD in effluent. Further, the process of present invention provides for viscosity reduction of the PVA from 1.68 cP to 1.01 cP after biodegradation, thereby confirming degradation or defilement of the PVA present in the polymer. Furthermore, the process of present invention provides for an environment friendly and sustainable textile manufacturing process by complete degradation of PVA complex chains present in the wastewater or effluent.
[0024] While the exemplary embodiments of the present invention are described and illustrated herein, it will be appreciated that they are merely illustrative. It will be understood by those skilled in the art that various modifications in form and detail may be made therein without departing from or offending the scope of the invention.

We claim:

1. A process for organic defilement of polymers present in
industrial wastewater, the process comprises:
mixing a polymer effluent with polymer decomposing microorganisms for biodegradation of the polymeric chain, wherein temperature of the polymer effluent mixed with the microorganisms is maintained in the range of between 21°C-45°C and a loading rate in the range of between 0.07 to 0.11 kg/kg; and
retaining the polymer effluent mixed with the microorganisms at a retention rate of at least 30 days, wherein after retention a treated effluent with sludge is formed.
2. The process as claimed in claim 1, wherein the polymer present in the effluent is polyvinyl alcohol (PVA) polymer.
3. The process as claimed in claim 1, wherein the microorganisms comprises at least microsporidia, euglena, rotaliida and sulcozoa.
4. The process as claimed in claim 1, wherein the polymer effluent is filtered using at least a disc shape filter with a pore size of 100 microns for removing fluff present in the polymer effluent.

5. The process as claimed in claim 1, wherein dissolved oxygen
(DO) maintained in the mixture of polymer effluent and microorganisms is in the range of between 1.5 ppm-2.5 ppm.
6. The process as claimed in claim 1, wherein the microorganisms are fed with a feed after microorganisms culture reproduce up to a pre-determined level, and wherein the feed comprises pollutants chemical oxygen demand (COD)/ biochemical oxygen demand (BOD) (COD/BOD) present in the effluent.
7. The process as claimed in claim 1, wherein the retention rate breaks complex chain of the polymer.
8. The process as claimed in claim 1, wherein the treated effluent and the sludge is separated by stagnation process, wherein the sludge settles down leaving the treated effluent.
9. The process as claimed in claim 8, wherein pH of the treated effluent is in the range of between 0.7 to 8.5.
10. The process as claimed in claim 8, wherein viscosity of the biologically degraded polymer is in the range of between 0.95 cP to 1.1 cP.
11.The process as claimed in claim 1, wherein the sludge is recirculated using a pumping mechanism at low speed and subjected to aerobic microbial conditions for biodegradation of the polymer, and wherein the recirculation of the activated sludge is carried out continuously for maintaining activated sludge volume in

order to provide efficient degradation of the effluent by ensuring adequate feed rate.