A system for the removal of suspends from wastewater and method thereof

Abstract

A method and system for the removal of suspends and contaminants from waste water is disclosed. Said method broadly comprises a step of passing water through a suspends removal system (106), said suspends removal system (106) involving coagulation (114) and flocculation (115), to remove the undesirable contaminants and to obtain treated water. The disclosed system and method offer at least the following advantages: promote aeration of effluent treatment plants; efficiently remove suspends, leading to better effluents suitable for recirculation or safe discharge; reduce operational costs by removing the suspends, which affect biological oxidation and cause frequent periodic maintenance of biological systems; and contribute to more sustainable water treatment practices.

Description

[0001] TITLE OF THE INVENTION: A SYSTEM FOR THE REMOVAL OF SUSPENDS FROM WASTEWATER AND METHOD THEREOF

[0002] FIELD OF THE INVENTION

[0003] The present disclosure is generally related to treatment of water. Particularly, present disclosure is related to the treatment of industrial waste water. More particularly, the present disclosure is related to a system, for the removal of suspends and contaminants from industrial waste water, and a method thereof.

[0004] BACKGROUND OF THE INVENTION

[0005] Aeration is used by ETPs (Effluent Treatment Plant) in the biological oxidation step of wastewater treatment to aid in the breakdown of organic materials and the removal of contaminants. The process of aeration involves adding oxygen to the wastewater to encourage the development of aerobic bacteria, which break down organic pollutants. For these bacteria to efficiently carry out their metabolic processes, there must be a sufficient amount of dissolved oxygen, healthy and nontoxic living conditions available. In a Zero Liquid Discharge system, the pre-filtration system reject is continuously recirculated to the biological aeration system, if suspends and contaminants are present in the recirculated pre-filtration reject stream, the biological system is burdened more and become toxicity by the effluent's potential presence and accumulation of several suspended (or un-settleable) materials and contaminants, such as sulphur dyes, oligomers, filamentous bacteria, colloidal particles, dead mass, and / or the like which are non / slowly bio-degradable. It is laborious to handle or remove these suspends and contaminants from a cyclic process.

[0006] In an Effluent Treatment Plant (ETP), the recycling of such suspends during the aeration process results in a vicious circle of negative effects. This cycle creates a negative feedback loop that worsens the operational difficulties and compromises the quality of treated effluent. The biological load in the aeration process is affected and the treatment as a whole is affected by the continuous recirculation of such suspends.

[0007] There is, therefore, a need in the art for: a system, for the removal of suspends and contaminants from industrial wastewater, and a method thereof, which overcomes the aforementioned drawbacks and shortcomings. SUMMARY OF THE INVENTION

[0008] A method and system for the removal of suspends from waste water are disclosed. Said method broadly comprises following steps:

[0009] First, reject stream from micro / ultra filtration or submerged membrane bio reactor is passed through a suspends removal system. Said suspends removal system involves coagulation and flocculation, to remove the suspends and contaminants and to obtain treated water. After coagulation and floculation process the stream is passed through a lamella settler, where the suspends and contaminants will be settled by gravity.

[0010] The disclosed system and method offer at least the following advantages: promote healthier aeration system of effluent treatment plants; efficiently remove suspends, leading to better effluents suitable for recirculation; reduce operational costs by removing the suspends, which affect biological oxidation and cause frequent periodic maintenance of biological systems; and contribute to more sustainable water treatment practices.

[0011] BRIEF DESCRIPTION OF THE DRAWINGS

[0012] Figure l is a flow chart that illustrates a system and method, for treatment and removal of suspends, in accordance with an embodiment of the present disclosure;

[0013] Figure 2 is a flow chart that illustrates a system and method, for the removal of suspends from industrial wastewater, in accordance with an embodiment of the present disclosure; and

[0014] Figure 3 is a flow chart that illustrates a system and method, for the removal of suspends from industrial wastewater, in accordance with another embodiment of the present disclosure

[0015] DETAILED DESCRIPTION OF THE INVENTION

[0016] Throughout this specification, the use of the words “comprise” and “include”, and variations (such as “comprises”, “comprising”, “includes”, and “including”) may imply the inclusion of an element (or elements) not specifically recited. Further, the disclosed embodiments may be embodied in various other forms as well. Throughout this specification, the use of the word “system” is to be construed as: “a set of technical components (also referred to as “members”) that are communicatively and / or operably associated with each other, and function together as part of a mechanism, to achieve a desired technical result”.

[0017] Throughout this specification, the word “suspends”, and its variations, such as suspended materials, unsettleable materials, contaminants etc., is to be construed as inclusive of sulphur dyes, oligomers, filamentous bacteria, colloidal particles, dead mass, and / or the like.

[0018] Throughout this specification, the word “effluents” is to be construed as inclusive of waste water from industrial plants, sewage treatment plants, and agricultural operations that contains wide range of pollutants, including heavy metals, chemicals, pathogens, organic matter, and nutrients such as nitrogen and phosphorous.

[0019] Throughout this specification, where applicable, the use of the phrase “at least” is to be construed in association with the suffix “one”, the suffix “two”, or the suffix “four” i.e. it is to be read along with the suffix “one”, as “at least one”, which is used in the meaning of “one or more” (likewise for the other suffixes). A person skilled in the art will appreciate the fact that the phrase “at least one” is a standard term that is used in Patent Specifications, to denote any component of a disclosure, which may be present (or disposed) in a single quantity, or more than a single quantity (likewise for the other suffixes).

[0020] Throughout this specification, the word “effluents”, the phrase “waste water”, and the word “wastewater” are used interchangeably.

[0021] Throughout this specification, the words “the” and “said” are used interchangeably.

[0022] Throughout this specification, the phrases “at least a”, “at least an”, and “at least one” are used interchangeably.

[0023] Also, it is to be noted that embodiments may be described as a method. Although the operations in a method are described as a sequential process, many of the operations may be performed in parallel, concurrently, or simultaneously. In addition, the order of the operations may be re-arranged. A method may be terminated when its operations are completed, but may also have additional steps.

[0024] The primary objective is to remove the suspends and contaminants and to produce a cleaner effluent that can be safely recirculated to the biological system and to maintain a healthier biological system, contributing to sustainable water management practices.

[0025] A system and method, for the removal of suspends from industrial wastewater, is disclosed. The disclosed system and method shall be explained with the help of Figure 1, Figure 2 and Figure 3, as follows.

[0026] Waste water (101) is collected, screened, and stored in a lifting sump (102). The screened waste water (102) then undergoes neutralization and equalization (103) before being processed in a cooling tower (104), followed by treatment in a biological tank (105), and separation in a lamella settler (107) and to obtain a sludge and a biologically treated water. The obtained sludge is thickened in a sludge thickener (108) and then the obtained biologically treated water is subjected to microfiltration and a submerged membrane bioreactor (MBR) (109) to obtain a treated water.

[0027] The reject water from the MF / UF / MBR system is then processed through a Suspends / Contaminants removal system (106) and then to a biological tank (105). The recirculated stream after removing the suspends will mix with the inlet effluent stream in the biological tank (105), the treated water passes through the lamella settler (107), the SMBR (109), a degasser tower (110), and a reverse osmosis unit (111) to obtain reject water (112), with the permeate collected in a RO permeate tank (113).

[0028] As illustrated, in Figure 2, said system and method broadly involve: coagulation (114) and flocculation (115). The coagulation involves the use of chemical coagulants (for example, aluminium sulphate, aluminium chloride, sodium aluminate, and / or the like) that neutralize the negatively charged particles present in the wastewater. By neutralizing these charges, the repulsive forces between particles are minimized, allowing them to come together and form aggregates, known as flocs. This process creates larger and more manageable particles, making it easier to remove contaminants during subsequent treatment stages. The disclosed system is configured to handle wastewater from two different sources: A Micro Filtration / Ultra Filtration (MF / UF) unit or the submerged membrane bio reactor (S-MBR) unit (109). In the MF / UF unit, the reject water, which contains unwanted particles along with suspends are captured, is conveyed through a pipeline using the pressure generated by the MF / UF systems. The pipeline efficiently directs the reject water to a coagulation and flocculation system or to a mixing trench (117).

[0029] Similarly, if in case of S-MBR unit (109), drain water containing unwanted particles along with the suspends is discharged by a pump and sent to the coagulation and flocculation system or the mixing trench (117) for chemical dosing (for example, sodium hypochlorite, sulphuric acid, ferric chloride, phosphoric acid, and / or the like), as illustrated, in Figure 3.

[0030] The mixing trench (117) is a pathway where the reject water, with added coagulants, encounters a series of blockages or obstacles. These blockages promote the thorough mixing of the chemicals with the effluents (101), enhancing the reaction between the coagulants and the contaminants. As a result, larger and heavier flocs are formed, thereby, improving their settling ability during a subsequent settling step.

[0031] After the coagulation (114), the wastewater proceeds to the flocculation (115) stage, where gentle mixing or stirring encourages the collision and adhesion of destabilized particles. This process further promotes floc formation, enhancing the efficiency of particle removal. Following the flocculation (115) stage, or the mixing trench (117) stage, the wastewater is subjected to a Lamella settler (107), which efficiently separates the flocs from the water. The settler allows clear water to be recirculated safely back to biological system in order to improve the overall performance, while the removed flocs are collected and concentrated in sludge thickeners (108).

[0032] The disclosed system and method offer at least the following advantages: promote healthier aeration system of effluent treatment plants; efficiently remove suspends, leading to better effluents suitable for recirculation; reduce operational costs by removing the suspends, which affect biological oxidation and cause frequent periodic maintenance of biological systems; and contribute to more sustainable water treatment practices. It will be apparent to a person skilled in the art that the above description is for illustrative purposes only and should not be considered as limiting. Various modifications, additions, alterations, and improvements, without deviating from the spirit and the scope of the disclosure, may be made by a person skilled in the art. Such modifications, additions, alterations, and improvements should be construed as being within the scope of this disclosure.

[0033] LIST OF REFERENCE NUMERALS

[0034] 101 - Effluent / Waste Water

[0035] 102 - Screener or Lifting Sump

[0036] 103 - Equalisation and Neutralisation

[0037] 104 - Cooling Tower

[0038] 105 - Biological Tank

[0039] 106 - Suspends Removal System

[0040] 107 - Lamella Settler

[0041] 108 - Sludge Thickener

[0042] 109 - Micro / Ultra Filtration or Submerged Membrane Bio Reactor

[0043] 110 - Degasser Tower

[0044] 111 - Reverse Osmosis (RO)

[0045] 112 - Reject Water

[0046] 113 - Reverse Osmosis (RO) Permeate Tank

[0047] 114 - Coagulation

[0048] 115 - Flocculation

[0049] 116 - Direct Chemical Dosing

[0050] 117 - Mixing Trench

Claims

CLAIMSWe claim:

1. A method for the removal of suspends or contaminants from waste water, comprising steps of: passing reject stream from micro / ultra filtration or submerged membrane bio reactor (109) through a suspends removal system (106), said suspends removal system (106) involving coagulation (114) and flocculation (115), to obtain treated water; after coagulation and flocculation, the stream is passed through a lamella settler (107), where the suspends and undesirable contaminants are settled by gravity.

2. The method for the removal of suspends from waste water, as claimed in claim 1, wherein the coagulation (114) and flocculation (115) take place as two separate stages.

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