CN212687862U

CN212687862U - Cassava starch production sewage treatment system

Info

Publication number: CN212687862U
Application number: CN202022151011.3U
Authority: CN
Inventors: 陈向前; 邓辅唐; 曾郴林
Original assignee: Yunnan Kingyear Ecological Construction Group Co ltd
Current assignee: Yunnan Kingyear Ecological Construction Group Co ltd
Priority date: 2020-09-27
Filing date: 2020-09-27
Publication date: 2021-03-12
Anticipated expiration: 2030-09-27

Abstract

The invention belongs to the field of sewage treatment, and particularly relates to a cassava starch production sewage treatment system, which is characterized in that a grid well, a flocculation sedimentation tank, a regulating tank, an air floatation tank, a hydrolysis acidification tank and a biological aerated filter are sequentially connected, namely, an outlet of the grid well is connected with an inlet of the flocculation sedimentation tank, an outlet of the flocculation sedimentation tank is connected with an inlet of the regulating tank, the air floatation tank is provided with a scum outlet and a liquid outlet, the liquid outlet is connected with an inlet of the hydrolysis acidification tank, the scum outlet is discharged, an outlet of the hydrolysis acidification tank is connected with an inlet of the biological aerated filter, and an outlet of the biological aerated filter reaches the discharge standard.

Description

Cassava starch production sewage treatment system

Technical Field

The invention belongs to the field of sewage treatment, and particularly relates to a cassava starch production sewage treatment system.

Background

The common treatment of the cassava starch wastewater comprises the following steps: and (4) standard discharge treatment and process recycling treatment. The standard discharge treatment is carried out according to the discharge standard required by the environmental protection regulatory agency of the local government, and the treated waste water can be discharged into the urban sewage pipe network after reaching the required standard. The process recycling treatment is to recycle the cassava starch wastewater after treatment for greening irrigation or participating in partial cassava washing, and the recycled water has no negative influence on the subsequent greening process and washing quality, thereby saving water and being beneficial to better reducing the cost. The characteristics of the cassava starch wastewater determine the treatment process flow, and the effluent after the system treatment must meet the following basic conditions: (1) the biological oxygen sensor is safe and reliable in sanitation, has no harmful substances, and has the main measurement indexes of the biological oxygen sensor, such as the number of coliform groups, the total number of bacteria, the amount of suspended matters, biochemical oxygen demand, chemical oxygen demand and the like; (2) the appearance has no unpleasant feeling, and the main measurement indexes of the appearance comprise turbidity, chroma, odor, surfactant, grease and the like; (3) does not cause serious corrosion, structure and maintenance management difficulty of equipment, pipelines and the like, and has a main measurement index of pH value.

The methods used at present can be roughly classified into three categories: (1) the organic pollutants in the water are removed by a physical and aerobic combined process and biochemical technologies such as hydrolytic acidification, contact oxidation and the like. Because a large amount of solid suspended substances exist in the cassava starch wastewater, pretreatment and hydrolytic acidification are carried out before treatment, so that the biodegradability of the wastewater is increased.

(2) Membrane processing techniques are used. Novel systems developed by combining membrane separation technology with biological treatment processes are treated by ultrafiltration (microfiltration), or MBR methods. But the adopted membrane technology has the following characteristics: high initial investment cost, high running cost, complex operation management, high later maintenance and operation cost and the like. According to the experience of our company, the membrane is generally replaced once in about two years. There is a need for a more efficient wastewater treatment system.

Disclosure of Invention

In order to solve the technical problems, the invention provides a cassava starch production sewage treatment system which can effectively treat cassava starch production sewage.

The specific technical scheme is as follows: after being collected, the wastewater firstly enters a grating well to intercept large-particle impurities, then enters a flocculation sedimentation tank to carry out flocculation sedimentation so as to remove large-particle substances in the wastewater, and then enters an adjusting tank to carry out water quality and water quantity adjustment; under the condition of adding polyaluminium chloride and polyacrylamide, enabling the wastewater to enter an air floatation tank for air floatation treatment by using a lift pump, and removing solid suspended substances, partial COD (chemical oxygen demand) and part BOD (biochemical oxygen demand) in the wastewater;

after air floatation treatment, the wastewater enters a hydrolysis acidification tank for hydrolysis acidification, so that the overall biodegradability of the wastewater is improved; the wastewater after hydrolysis and acidification enters an aeration biological filter for advanced treatment, and the COD and BOD content in the wastewater is reduced to reach the discharge standard.

Further, the processing system is as follows: including grid well, flocculation and precipitation pond, equalizing basin, air supporting pond, hydrolysis acidification pond, bological aerated filter, grid well, flocculation and precipitation pond, equalizing basin, air supporting pond, hydrolysis acidification pond, bological aerated filter connect gradually, and the grid well setting is in production waste pipe tail end below, be provided with the medicine mouth on the equalizing basin, the air supporting pond is provided with dross export and liquid outlet, liquid outlet and hydrolysis acidification pond entry linkage, and the dross export is arranged outward. Grid well, flocculation and precipitation pond, equalizing basin, air supporting pond, hydrolysis-acidification pool, bological aerated filter are connected in proper order, and the export of grid well and flocculation and precipitation pond's entry linkage promptly, flocculation and precipitation pond's export and equalizing basin entry linkage, air supporting pond are provided with dross export and liquid outlet, liquid outlet and hydrolysis-acidification pool entry linkage, and the dross export is arranged outward, hydrolysis-acidification pool export and bological aerated filter entry linkage, and bological aerated filter exports outward.

Has the advantages that: the method adopts a physical and chemical method and a biological method for combined treatment, after the wastewater is collected, large particle impurities are intercepted through a grating well, the wastewater enters a flocculation sedimentation tank for flocculation sedimentation to remove large particle substances in the wastewater, and then the wastewater enters an adjusting tank for water quality and water quantity adjustment; under the condition of adding polyaluminium chloride and polyacrylamide, enabling the wastewater to enter an air floatation tank for air floatation treatment by using a lift pump, and removing solid suspended substances, partial COD (chemical oxygen demand) and part BOD (biochemical oxygen demand) in the wastewater; after air floatation treatment, the wastewater enters a hydrolysis acidification tank for hydrolysis acidification, so that the overall biodegradability of the wastewater is improved; the wastewater after hydrolysis and acidification enters an aeration biological filter for advanced treatment, and the COD and BOD content in the wastewater is reduced to reach the discharge standard.

Drawings

Fig. 1 is a device contact diagram of the present invention.

Detailed Description

As shown in figure 1, after being collected by a pipe network, the wastewater firstly intercepts large granular impurities through a grid well, enters a flocculation sedimentation tank for flocculation sedimentation to remove large granular substances in the wastewater, and then enters an adjusting tank for water quality and water quantity adjustment. Under the condition of adding a special medicament, the wastewater enters an air floatation tank for air floatation treatment by using a lift pump, and solid suspended substances, partial COD (chemical oxygen demand) and partial BOD (biochemical oxygen demand) in the wastewater are removed.

The wastewater enters a hydrolysis acidification tank for hydrolysis acidification after air floatation treatment, so that the overall biodegradability of the wastewater is improved. The wastewater after hydrolysis and acidification enters an aeration biological filter for advanced treatment, and the COD and BOD content in the wastewater is reduced to reach the discharge standard.

Flocculation sedimentation system (flocculation sedimentation tank)

The flocculation precipitation system is a method for reducing the stability of colloidal solution by adding flocculant (coagulant aid is sometimes needed) and making it coagulate and precipitate, then separating and purifying, and its technological process is simple, efficiency is high and cost is low.

Through flocculation and precipitation, large-particle impurities in the wastewater can be removed and precipitated, so that the water quality of the wastewater is improved, and better conditions are created for the subsequent treatment process. The impurities which can be effectively reduced in the flocculation precipitation process are COD, BOD, solid suspended matters and the like in the wastewater.

Air flotation system (air flotation tank)

The air flotation is a process of forming highly dispersed micro bubbles in water, adhering solid or liquid particles of hydrophobic groups in wastewater to form a water-gas-particle mixed system, forming flocs with apparent surface density smaller than that of water after the particles adhere to the bubbles, floating to the water surface, forming a scum layer and scraping out, thereby realizing solid-liquid or liquid-liquid separation.

The dissolved air water generated by the dissolved air system is released in water through rapid decompression to generate a large amount of micro bubbles, a plurality of bubbles are adhered to the surfaces of flocculated impurity particles in the water to form suspended matters with the integral density less than 1, and the suspended matters are lifted to the water surface through buoyancy to separate solid from liquid. The complete air floating device integrates an air floating tank, a dosing device, a dissolved air tank, a dissolved air pump and an air compressor. The installation time can be shortened, and the workload can be reduced. The floor area is small, the operation is convenient and no foundation is needed. The sewage with the pH value adjusted by a user unit is poured into and out of the pipe orifice and the like, and the sewage is normally operated without being managed by a special person once the sewage is adjusted, so that the operation basically reaches an automatic unattended state. The current air floating device of the pressurized dissolved air floating method has the widest application. Compared with other air flotation devices, the air flotation equipment has the following characteristics:

1. under the pressurization condition, the solubility of the air is high, the quantity of bubbles for air supply floatation is large, and the deceptive effect can be ensured.

2. The dissolved gas is suddenly decompressed and released, and the generated bubbles are fine, uniform in granularity, high in concentration, stable in floating and small in disturbance to liquid, so that the method is particularly suitable for solid-liquid separation of loose flocs and fine particles.

3. The air floatation equipment has simple process and is convenient to manage and maintain.

The project air floatation system can remove impurities such as cassava skin, gravel, pulp residue and the like in the wastewater.

Hydrolysis acidification system (hydrolysis acidification pool)

The hydrolysis (acidification) treatment method is a method between aerobic and anaerobic treatment methods, and other processes are combined to reduce treatment cost and improve treatment efficiency. The hydrolysis acidification process controls anaerobic treatment in the first and second stages of anaerobic treatment with short reaction time according to different growth speeds of methanogenic bacteria and hydrolysis acid-producing bacteria, namely, the process of hydrolyzing insoluble organic matters into soluble organic matters under the action of a large amount of hydrolysis bacteria and acidification bacteria and converting macromolecular substances which are difficult to biodegrade into small molecular substances which are easy to biodegrade, thereby improving the biodegradability of wastewater and laying a good foundation for subsequent treatment.

Hydrolysis refers to the biochemical reaction that occurs extracellularly before the organic material enters the microbial cells. The microorganism completes the biocatalytic reaction by releasing free extracellular enzymes or immobilized enzymes attached to the outer wall of the cell.

Acidification is a typical fermentation process, and the metabolites of microorganisms are mainly various organic acids. The advantages of hydrolytic acidification are as follows:

(1) the pool body does not need to be closed, and a three-phase separator is not needed, so that the operation management is convenient and simple. And (2) after the macromolecular organic matters are hydrolyzed and acidified, micromolecular organic matters are generated, and biodegradability is good, namely, biodegradability of raw sewage can be changed by hydrolysis and acidification, so that reaction time and treatment energy consumption are reduced. And (3) hydrolytic acidification belongs to the early stage of anaerobic treatment, and does not reach the final stage of anaerobic fermentation, so that the effluent does not have the unpleasant smell generated by anaerobic fermentation, and the environment of a sewage treatment plant is improved. And (4) the time required by the hydrolysis acidification reaction is short, so the required building volume is small and is generally equivalent to that of a primary sedimentation tank, and the capital investment can be saved. And (5) the hydrolytic acidification has good degradation effect on solid organic matters, and the generated residual sludge is little, so that the sludge and sewage are treated at one time, and the digestion tank has partial functions.

Aeration biological filter

A Biological Aerated Filter (BAF) is an aerobic or anoxic bioreactor adopting a granular Filter material to fix a Biological membrane, integrates the functions of Biological contact oxidation and suspended matter Filter bed interception, and is an international emerging new sewage treatment technology. The method has the functions of removing solid suspended matters, CODcr, BOD, nitrification and denitrification, nitrogen and phosphorus removal and AOX removal, and is mainly characterized by integrating biological oxidation, interception, suspension and fixation and saving a subsequent secondary sedimentation tank.

The wood water starch wastewater treated by the hydrolytic acidification tank enters a first-stage BAF-C/N filter tank, most of COD and BOD are degraded, part of ammonia nitrogen is nitrified (or denitrified), then the sewage enters a second-stage BAF-N filter tank, the ammonia nitrogen is thoroughly nitrified, the COD and the BOD are further degraded, and chemical phosphorus removal is carried out to ensure the quality of the effluent water.

The technical characteristics are as follows:

(1) the total investment is saved, including mechanical equipment, an automatic control electric system, civil engineering and land charge.

(2) The floor space is small, is usually 1/5-1/10 of the floor space of the conventional treatment process, and the plant area is compact and beautiful.

(3) The treated effluent has good quality and can reach the water quality standard of reclaimed water or the water quality standard of domestic miscellaneous water.

(4) Short technological process, high oxygen transmission efficiency, low oxygen supply power consumption and low power consumption for treating unit sewage. (5) The filtering speed is high, and the processing load is greatly higher than that of the conventional processing technology.

(6) Strong impact resistance, little influence by climate, water quantity and water quality change, is especially suitable for cold weather areas, and can run intermittently.

(7) Can be built into a closed factory building, reduces the influence of odor and noise on the surrounding environment and has good visual and sensory effects. (8) The operation management is convenient, and the maintenance is convenient.

(9) All the modular structures are convenient for reconstruction and expansion in the later period.

Wherein PAC is polyaluminium chloride, and PAM is polyacrylamide.

Effect of treatment

Claims

1. The utility model provides a cassava starch production sewage treatment system, its characterized in that, includes grid well, flocculation and precipitation pond, equalizing basin, air supporting pond, hydrolysis acidification pond, bological aerated filter, and grid well, flocculation and precipitation pond, equalizing basin, air supporting pond, hydrolysis acidification pond, bological aerated filter connect gradually, and the grid well setting is in production waste pipe tail end below, be provided with on the equalizing basin and add the medicine mouth, the air supporting pond is provided with dross export and liquid outlet, liquid outlet and hydrolysis acidification pond entry linkage, and the dross export is arranged outward.