CN202492411U - Combination of sludge circulation with jet aeration of landfill leachate treatment system - Google Patents

Abstract

A sludge circulation and jet aeration combination of a landfill leachate treatment system includes a water intake valve, a circulation pump switching valve group, a circulation pump A, a circulation pump B, a heat exchanger, a regulating valve A, an electromagnetic flowmeter, a regulating valve B, Electric control unit, pressure transmitter, return valve, blower, multi-unit jet aerator, use the same pump to complete the functions of sludge circulation cooling and jet aeration successively. It can not only meet the needs of aerobic tank sludge cycle cooling, keep the temperature within a suitable range, but also ensure high aeration efficiency and oxygen utilization rate, so that organic matter can be fully degraded. Compared with conventional sludge circulation and jet aeration process schemes, the utility model reduces the number of water pumps, not only saves equipment investment costs, equipment installation costs and system operating costs, saves floor space, and can realize automatic control, It has the obvious advantages of economy and energy saving.

Description

Combination of sludge circulation and jet aeration in a landfill leachate treatment system

Technical field

The invention relates to a combination of sludge circulation and jet aeration in a landfill leachate treatment system, belonging to the technical field of sewage treatment. the

Background technique

During the process of stacking and landfilling garbage, a large amount of percolation liquid will be produced. It is a kind of high-concentration organic wastewater with a COD concentration between 30,000 and 70,000 mg/L. The composition is quite complex and it is difficult to treat. Many domestic waste landfills and waste incineration power plants are facing this problem. At present, "anaerobic + aerobic treatment" is the mainstream process for treating landfill leachate. This process can degrade most organic pollutants through anaerobic reactors, improve the biodegradability of wastewater, reduce its toxicity, and generate biogas for recycling. Utilization; and then through subsequent aerobic treatment to further degrade and remove low-molecular organic pollutants. After the above two processes, most of the pollutants in the leachate can be basically removed. the

In order to ensure that the treatment reaches the standard, the treatment of high-concentration sewage has higher requirements on aeration efficiency. Ordinary microporous aeration method is not very suitable for landfill leachate treatment due to its low aeration efficiency and easy clogging. Jet aeration has been widely used in the field of leachate treatment due to its high aeration efficiency and oxygen utilization rate, and avoiding the problem of aerator clogging. However, jet aeration often requires the use of a blower. The continuous work of the blower results in a higher temperature of the air used for aeration. On the other hand, aerobic microorganisms will release heat during the process of oxidative degradation of organic matter. The aerobic pool generally has the problem of high temperature, especially in summer. Therefore, the aerobic pool sludge must be circulated and cooled in the process. the

The existing aerobic tanks are routinely set up so that the sludge circulation cooling subsystem and the jet aeration subsystem operate separately, which requires the sludge circulation pump and the jet pump to be installed separately, and at least one of the two pumps must be used and the other must be in standby, and the equipment occupies an area of Larger area. In addition, in order to ensure the heat exchange effect, the flow rate of the sludge circulation pump is generally large, and the head is also high. The sludge cooled by the heat exchanger still has a large energy. This part of energy is completely wasted after the sludge returns to the aerobic tank. This waste is huge for many years. At the same time, the jet pump completes the process of oxygenation, stirring and mixing of the water body through the injection of high-energy fluid. It can be seen that in the conventional sludge circulation and jet aeration process system, on the one hand, there is a waste of energy, on the other hand, there is a lack of energy, and there is a necessity and potential for improvement. the

Contents of the invention

The object of the present invention is to provide a more economical and energy-saving combination of sludge circulation and jet aeration for the landfill leachate treatment system in view of the deficiencies in the prior art. the

A sludge circulation and jet aeration combination of a landfill leachate treatment system, including a water intake valve, a circulation pump switching valve group, a circulation pump A, a circulation pump B, a heat exchanger, a regulating valve A, an electromagnetic flowmeter, and a regulating valve B , electrical control unit, pressure transmitter, return valve, blower, multi-unit jet aerator, the water intake valve is installed in the water inlet pipeline, and the circulation pump A and circulation pump B are installed in two bypass pipelines separated from the water inlet pipeline , the circulating pump switching valve group is installed at the front and rear ends of circulating pump A and circulating pump B. After the two bypass pipelines merge, they are divided into two bypass pipelines. One of the bypass pipelines is equipped with a cooling tower, and a cooling tower is installed in front of the cooling tower. Regulating valve A, an electromagnetic flowmeter is installed behind the cooling tower, and a regulating valve B is installed in the other bypass pipeline. After the two bypass pipelines merge, the pipeline is installed with a pressure transmitter, a return valve, and a blower before entering the aerobic pool. It is connected to the multi-unit jet aerator through pipelines, and the electrical control unit is connected to the circulation pump, regulating valve and pressure transmitter through the control line, among which circulation pump A and circulation pump B are controlled by frequency conversion, and serve as sludge circulation pump and jet pump at the same time use and serve as backups for each other. After the sludge (mud-water mixture) in the aerobic tank is sucked by the circulating pump, most of it enters the sludge circulation cooling subsystem (heat exchanger) for cooling, and a small part is distributed through the designed bypass pipeline. The muddy water conveyed by the confluence bypass flows to the jet aerator to form a high-speed jet water flow, which is mixed with the air blown by the blower to complete the jet aeration. the

The beneficial effects of the combined implementation of sludge circulation and jet aeration in a landfill leachate treatment system of the present invention are:

(1) Better economy. One pump is multi-purpose, that is, the circulation pump doubles as a jet pump and a sludge circulation pump. In the case of one use and one backup, two pumps can be saved, which reduces equipment costs. The reduction of the number of water pumps means the reduction of equipment investment cost, the reduction of equipment footprint, the reduction of equipment installation workload and the reduction of system operation cost. the

(2) Better energy-saving effect. Assuming that the sludge circulation subsystem and the jet aeration subsystem operate independently, the required flows of the sludge circulation pump and the jet aeration pump are Q1 and Q2 respectively, and the lifts are H1 and H2 respectively. According to the design of the present invention, the sludge circulating cooling pump and the jet aeration pump are combined into one, the flow rate of the designed circulating pump is Q, and the head is H, then max(Q1, Q2)≤Q<Q1+Q2, and the head is H : max(H1, H2)≦H<H1+H2. Since the present invention combines two pumps into one and effectively utilizes the residual energy of cooling sludge at the outlet of the heat exchanger in the conventional design, the total amount of water to be lifted Q is significantly lower than that of Q1+Q2, and the head is similar, so the required pumping capacity of the present invention is The total power consumption is much smaller than that of the conventional design, thus showing a better energy-saving effect. the

(3) Improve the processing effect. After the sludge in the aerobic tank is cooled by the heat exchanger, it is aerated by the multi-unit jet aerator. After aeration, the oxygen saturation solubility in the sludge will increase due to the decrease of the sludge temperature. Therefore, this design is more It is conducive to the improvement of jet aeration efficiency and oxygen utilization rate. the

(4) The control is convenient and flexible. In the present invention, regulating valves and electromagnetic flowmeters are respectively arranged before and after the heat exchanger, regulating valves are arranged on side branch pipelines, and pressure transmitters are arranged in front of multi-unit jet aerators. The unit can conveniently control the circulation pump to ensure that the sludge circulation cooling flow and jet aeration flow requirements can be met at the same time. the

Description of drawings

Figure 1 Schematic diagram of common sludge circulation and jet aeration process

Figure 2 is a combined schematic diagram of sludge circulation and jet aeration in a landfill leachate treatment system

Among them, 1-water intake valve, 2-circulation pump switching valve group, 3-circulation pump A, 4-circulation pump B, 5-heat exchanger, 6-regulating valve A, 7-electromagnetic flowmeter, 8-regulating valve B , 9-electric control unit, 10-pressure transmitter, 11-return valve, 12-blower, 13-multi-unit jet aerator. the

Detailed ways

The present invention relates to a sludge circulation and jet aeration combination of a landfill leachate treatment system, as shown in Figure 1, comprising: a water intake valve 1, a circulation pump switching valve group 2, a circulation pump A3, a circulation pump B4, Heater 5, regulating valve A6, electromagnetic flowmeter 7, regulating valve B8, electrical control unit 9, pressure transmitter 10, return valve 11, blower 12, multi-unit jet aerator 13, etc. the

The present invention is when carrying out, and circulation pump A3 and circulation pump B4 are that one is used and one is prepared, switches by circulation pump switching valve group 2. The electrical control unit 9 includes two frequency converters, which can conveniently realize the frequency conversion control of the circulating pump A3 and the circulating pump B4. Circulation pump A3 or circulation pump B4 is a dual-purpose pump, which is also used as a sludge circulation cooling pump and a jet aeration pump. the

When the present invention is implemented, the circulation pump A3 (or circulation pump B4) sucks the sludge (mud-water mixture) in the aerobic pool through the water intake valve 1, and adjusts the regulating valve A6 and regulating valve A6 and regulating valve respectively or simultaneously according to the data displayed by the electromagnetic flowmeter 7. The opening of valve B8 is mainly to ensure the flow supply required for sludge circulation and cooling, and to properly adjust the sludge circulation volume according to the temperature of the aerobic tank, that is, the greater the sludge circulation volume, the greater the heat exchange sludge volume, and the aerobic The temperature of the pool drops even more. According to the data displayed by the pressure transmitter 10, it is judged whether the flow and pressure requirements of the jet aeration can be met after the circulation cooling branch and the bypass mud-water mixture merge. If it is not satisfied, adjust the frequency of the sludge circulating pump A3 or sludge circulating pump B4, increase the opening of the regulating valve B8, and supplement the flow and pressure head through the bypass pipeline. It is also possible to change the flow rate and pressure of the jet aerator inlet pipe by adjusting the opening of the return valve 11, so that when the return sludge passes through the multi-unit jet aerator 13, a high-speed jet flow can be formed, and the air blown by the blower 12 can be sucked. , Mix well in the aerobic tank to achieve a good aeration effect. the

When the influent water temperature is low in winter, the sludge in the aerobic tank can be maintained at an appropriate temperature range without heat exchange and cooling. At this time, the regulating valve A6 can be closed to cut off the heat exchange and cooling circulation branch, and the regulating valve B8 can be opened. By changing the frequency of the circulating pump and the opening of the regulating valve B8, the flow rate can be controlled to meet the needs of jet aeration. At this time, the circulation pump is only equivalent to the jet pump, which not only avoids the idle waste of the sludge circulation pump and the jet pump in the conventional process when the temperature is low in the cold season when the sludge circulation pump and the jet pump are independent, but also does not affect the normal operation of the jet aeration system . the

Claims (2)

1. circulation of the mud of a garbage percolation liquid treating system and jet-flow aeration combination; Comprise water intake valve, recycle pump switching valve group, recycle pump A, recycle pump B, interchanger, variable valve A, magnetic flow meter, variable valve B, electric control unit, pressure unit, reverse flow valve, gas blower, multiple-unit jet aerator; Water intake valve is installed in suction culvert; Recycle pump A and recycle pump B are installed in two by-pass lines that suction culvert separates; Recycle pump switching valve group is installed in recycle pump A and recycle pump B front and back end, and two common pipe roads are divided into the two-way by-pass line after the interflow again, and wherein siphunculus road, a roadside is equipped with cooling tower; In the cooling tower front variable valve A is installed; Cooling tower is equipped with magnetic flow meter at the back, and another siphunculus road, roadside is equipped with variable valve B, and back, interflow, two common pipe roads pipeline is equipped with pressure unit and reverse flow valve before getting into Aerobic Pond; Gas blower and multiple-unit jet aerator are through pipe connection, and electric control unit connects recycle pump, variable valve and pressure unit through wire.

2. circulation of the mud of a kind of garbage percolation liquid treating system according to claim 1 and jet-flow aeration combination, but it is characterized in that described recycle pump A or recycle pump B double as jet-pump and sludge circulation pump.

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