CN-122010224-A - Process and method for removing DOM in initial rainwater

Abstract

The invention belongs to the technical field of water treatment, and discloses a process and a method for removing DOM in initial rainwater, aiming at the problems that DOM components in runoff rainwater are complex, the removal rate of the traditional process is low, membrane pollution is easy to cause, a powder catalyst is difficult to recycle and the like. Realize the efficient removal of DOM in the initial rainwater and the membrane pollution control. Under the operation of the optimized working condition, the Total Organic Carbon (TOC) removal rate can reach more than 83 percent. The method has the advantages of simple process, stable operation, recoverable catalyst, suitability for high-efficiency recycling of rainwater, and good engineering practical application potential.

Inventors

• CAI MINMIN
• Ge Hengbi
• MENG BIN
• YU LIYAO
• FENG CHANGJIANG
• ZHU ZIJIAN
• WEI YONG

Assignees

• 江苏省方圆建筑设计研究有限公司

Dates

Publication Date

20260512

Application Date

20260323

Claims (6)

1. 1. A process for removing DOM in rainwater by using a GAC/CuO/PS coupled ceramic membrane is characterized by comprising the following steps: (1) Introducing rainwater to be treated into a reactor provided with a ceramic membrane, adding Granular Activated Carbon (GAC) and copper oxide (CuO) powder into the reactor, and starting high-shear stirring to fully mix the GAC and the CuO in the rainwater; (2) Adding Persulfate (PS) into a reactor under the condition of continuously maintaining the high-shear stirring, activating the PS to generate free radicals under the action of GAC and CuO, and carrying out in-situ oxidative degradation on soluble organic matters in rainwater; (3) And starting a suction pump connected with the ceramic membrane to perform solid-liquid separation, discharging effluent into a water production tank, and intercepting the GAC, the CuO and the macromolecular pollutants which are not degraded completely in the reactor by the ceramic membrane to realize in-situ enrichment and recycling of the catalyst.
2. 2. The process for removing DOM in rainwater by using the GAC/CuO/PS coupled ceramic membrane, which is characterized in that the adding amount of GAC is 10-100 mg/L, cuO and 10-100 mg/L, and the adding concentration of PS is 100-1000 mg/L.
3. 3. The process for removing DOM in rainwater by using the GAC/CuO/PS coupled ceramic membrane according to claim 1, wherein in the step (1), the rotation speed of stirring at the high shearing rotation speed is set to 800-1000 rpm.
4. 4. The process for removing DOM from rainwater by using the GAC/CuO/PS coupled ceramic membrane according to claim 1, wherein the operation of steps (1) to (3) is performed in two stages of static circulation and dynamic operation: after adding the medicament, closing a system water outlet valve, and fully refluxing water produced by a suction pump into the reactor, and operating for 10-30 minutes; And the dynamic operation and membrane filtration stage, namely after the static circulation is finished, the water inlet pump continuously supplements raw water, the suction pump pumps purified water and discharges the purified water to the water production tank, and continuous flow filtration treatment is carried out.
5. 5. The process for removing DOM in rainwater by using the GAC/CuO/PS coupled ceramic membrane according to claim 1 is characterized in that in the step (3), the suction pump adopts an intermittent operation mode, the operation period is 8 minutes of suction and 2 minutes of stop, and the operation range of membrane flux is 10-100 LMH.
6. 6. The process for removing DOM in rainwater by using the GAC/CuO/PS coupled ceramic membrane according to claim 1, wherein the ceramic membrane is made of Al 2 O 3 and has an average pore diameter of 0.1 μm.

Description

Process and method for removing DOM in initial rainwater Technical Field The invention relates to the technical field of water treatment, in particular to a method for efficiently removing soluble organic matters (DOM) in rainwater based on CuO and GAC-cooperated activated PS advanced oxidation and coupled with a ceramic membrane and application thereof. Background Due to the rapid development of social economy and industrial agriculture, waste gas and waste water emission, excessive use of pesticides and fertilizers and the like, on one hand, the self-pollutants in the rainwater are increased, and on the other hand, the rainwater can carry pollutants such as heavy metals, organic matters, nitrogen and phosphorus through runoff action, so that the components of the pollutants in the rainwater are complex. The runoff rainwater carrying a large amount of unknown pollutants can enter the receiving water body through the rainwater pipeline, so that the variety and content of soluble organic matters (DOM) in the natural water body are continuously increased, and serious threat is formed to the ecology and public health safety of urban communities. However, conventional treatment methods, such as coagulation, flocculation and microbial degradation, hardly achieve an effective removal effect on DOM, and are prone to produce Disinfection Byproducts (DBPs) having a "tri-induced" effect, so that a problem of reclaimed water safety may occur when rainwater is used. The GAC/CuO/PS advanced oxidation coupling ceramic membrane technology provided by the invention not only can simply and efficiently remove DOM in rainwater, but also has the characteristics of stable operation, recoverable catalyst and effective control of membrane pollution. The activated carbon has larger specific surface area and rich polar functional groups, so the activated carbon becomes a better adsorption material and is widely applied to adsorbing pollutants in water bodies, such as heavy metals, ammonia nitrogen, DOM and the like, but in the previous research, the application of the activated carbon for removing the pollutants is concentrated in sewage and sludge, and the research of applying the activated carbon adsorption to removing the DOM in rainwater is less. However, at present, one of the main reasons for black and odorous river courses in China is that rainwater carries a large amount of DOM into water body through runoff action, so that water environment is damaged. Advanced oxidation processes (SR-AOPs) based on persulfate radicals have become a research hotspot in the field of water treatment due to their high adaptability and effectiveness in disinfecting and removing water pollutants. While current research has focused on the removal of contaminants by enhancing persulfate oxidation capability through the preparation of synthetic, supported metallic materials. However, the materials are complex to prepare and difficult to be used for large-scale rainwater treatment, and the research on the combined use of activated carbon and metal oxide to activate persulfate for treating rainwater is less at present, so the invention provides a method for directly adding GAC and CuO to activate PS, and simply and efficiently removing DOM in the rainwater. In order to solve the problems, the invention combines the active carbon adsorption and persulfate advanced oxidation technology, and is used for removing natural soluble organic matters (DOM) in actual rainwater. The system combines the utilization of CuO to cooperate with activated carbon to activate persulfate, and then the ceramic membrane filtration is coupled, so that not only is the DOM in rainwater removed efficiently, but also the catalyst CuO can be recovered through the membrane filtration and reused for multiple times, thereby reducing the economic cost. Provides theoretical basis and practical guidance for the practical application of the technology. Disclosure of Invention In order to solve the problems in the background art, the invention provides a combined process technical method for efficiently removing DOM in rainwater, which uses CuO to cooperate with Granular Activated Carbon (GAC) to activate Persulfate (PS) and is coupled with ceramic membrane filtration (CM), is different from the static curing load of a conventional composite catalytic material, adopts direct addition of free GAC and CuO, and forms a dynamic advanced oxidation system coupled ceramic membrane under a high shear force flow field, and has remarkable DOM removal effect on initial rainwater. Meanwhile, the invention explores the optimal addition amount of GAC, cuO and PS, and optimizes the operation system of the GAC/CuO/PS coupled ceramic membrane. The removal of UV 254 and TOC from stormwater was measured at different run times. The invention is realized by the following technical scheme, which comprises the following steps: (1) Pumping rainwater to be treated into a reactor provided with a flat ceramic mem