Aeration amount control system and aeration amount control method
阅读说明：本技术 曝气量控制系统及曝气量控制方法 (Aeration amount control system and aeration amount control method ) 是由 吉田航 林佳史 今村英二 野田清治 于 2018-02-27 设计创作，主要内容包括：获得能够降低曝气量控制系统的运转成本的曝气量控制系统和水处理方法。曝气量控制系统(100)基于目标曝气量对储存被处理水的膜分离槽(2)内的分离膜(3)进行曝气,其特征在于,具备：控制装置(7),将第1目标曝气量确定为目标曝气量,在确定第1目标曝气量后将第2目标曝气量确定为目标曝气量；曝气装置(5),基于目标曝气量供给气体而进行曝气；以及测量装置(6),测量分离膜(3)的膜间压差相对于曝气装置(5)所供给的气体的变化量,在测量装置(6)计算出的、曝气装置(5)进行基于第1目标曝气量的曝气的期间的分离膜(3)的膜间压差的第1变化量比测量装置(6)计算出的、曝气装置(5)进行基于第2目标曝气量的曝气的期间的分离膜(3)的膜间压差的第2变化量大的情况下,控制装置(7)将比第2目标曝气量小的值确定为第3目标曝气量。(An aeration control system and a water treatment method capable of reducing the running cost of the aeration control system are obtained. An aeration rate control system (100) for aerating a separation membrane (3) in a membrane separation tank (2) for storing water to be treated, on the basis of a target aeration rate, the system being characterized by comprising: a control means (7) for determining a 1 st target aeration amount as a target aeration amount and determining a 2 nd target aeration amount as a target aeration amount after determining the 1 st target aeration amount; an aeration device (5) that supplies gas based on a target aeration amount to perform aeration; and a measuring device (6) that measures the amount of change in the inter-membrane pressure difference of the separation membrane (3) with respect to the gas supplied by the aeration device (5), wherein the control device (7) determines a value that is smaller than the 2 nd target aeration amount as the 3 rd target aeration amount when the 1 st amount of change in the inter-membrane pressure difference of the separation membrane (3) calculated by the measuring device (6) during the period in which the aeration device (5) performs aeration based on the 1 st target aeration amount is larger than the 2 nd amount of change in the inter-membrane pressure difference of the separation membrane (3) calculated by the measuring device (6) during the period in which the aeration device (5) performs aeration based on the 2 nd target aeration amount.)
1. An aeration amount control system for aerating a separation membrane in a membrane separation tank storing water to be treated based on a target aeration amount,
the aeration amount control system is provided with:
a control means for determining a 1 st target aeration amount as the target aeration amount, and determining a 2 nd target aeration amount as the target aeration amount after determining the 1 st target aeration amount;
an aeration device that supplies gas based on the target aeration amount determined by the control device to perform the aeration; and
a measuring device that measures an amount of change in an inter-membrane pressure difference of the separation membrane with respect to the gas supplied by the aeration device,
in the case where the 1 st change amount of the inter-membrane pressure difference of the separation membrane during the period in which the aeration apparatus performs the aeration based on the 1 st target aeration amount, which is calculated by the measurement means, is larger than the 2 nd change amount of the inter-membrane pressure difference of the separation membrane during the period in which the aeration apparatus performs the aeration based on the 2 nd target aeration amount, which is calculated by the measurement means, the control means determines a value smaller than the 2 nd target aeration amount as the 3 rd target aeration amount.
2. The aeration control system of claim 1,
in the case where the 1 st change amount is smaller than the 2 nd change amount, the control means determines a value larger than the 2 nd target aeration amount as the 3 rd target aeration amount.
3. An aeration amount control system for aerating a plurality of separation membranes in a membrane separation tank storing water to be treated based on a target aeration amount,
the aeration amount control system is provided with:
a control device for setting a 1 st target aeration amount as the target aeration amount;
an aeration device that supplies gas based on the target aeration amount determined by the control device to perform the aeration; and
a measuring device that measures the amount of change in the inter-membrane pressure difference of the plurality of separation membranes with respect to the gas supplied by the aeration device, respectively,
the control means determines a value smaller than the 1 st target aeration amount as the 2 nd target aeration amount when the difference between the 1 st change amounts corresponding to the respective separation membranes during the period in which the aeration means performs the aeration based on the 1 st target aeration amount, which is calculated by the measurement means, is smaller than a threshold value.
4. The aeration control system of claim 3,
when the difference between the 1 st change amounts is equal to or greater than a threshold value, the control device determines a value greater than the 1 st target aeration amount as a 2 nd target aeration amount.
5. The aeration control system according to any one of claims 1 to 4,
the aeration amount control system is provided with an information acquisition device, and the information acquisition device is provided with:
a treated water information acquiring unit that acquires treated water information on the treated water in the membrane separation tank; and
and a storage medium that stores the information on the water to be treated, the target aeration amount calculated by the control device, and the amount of change in the pressure difference between membranes measured by the measurement device in association with each other.
6. An aeration amount control method in an aeration amount control system for aerating a separation membrane in a membrane separation tank storing water to be treated on the basis of a target aeration amount,
the aeration amount control method comprises:
an aeration amount determination step of determining a 1 st target aeration amount as the target aeration amount, and determining a 2 nd target aeration amount as the target aeration amount after determining the 1 st target aeration amount;
an aeration step of performing the aeration based on the target aeration amount supply gas determined by the aeration amount determination step; and
a variation calculating step of calculating a variation of an inter-membrane pressure difference of the separation membrane with respect to the gas supplied by the aerating step,
when a 1 st change amount of the inter-membrane pressure difference of the separation membrane during the period in which the aeration based on the 1 st target aeration amount is performed, which is calculated by the measuring means, is larger than a 2 nd change amount of the inter-membrane pressure difference of the separation membrane during the period in which the aeration based on the 2 nd target aeration amount is performed, which is calculated by the measuring means, a value smaller than the 2 nd target aeration amount is determined as a 3 rd target aeration amount.
7. The aeration rate control method according to claim 6,
in the case where the 1 st change amount is smaller than the 2 nd change amount, a value larger than the 2 nd target aeration amount is determined as the 3 rd target aeration amount.
Technical Field
The present invention relates to an aeration amount control system and an aeration amount control method using a separation membrane.
Background
As a method for treating wastewater containing organic substances (hereinafter, referred to as "water to be treated"), a Membrane separation activated sludge process (MBR: Membrane Bio Reactor) is used, in which organic substances in water to be treated are decomposed by microorganisms and solid-liquid separation is performed by a separation Membrane. In the filtration process using the separation membrane, when fouling substances adhere to the surface and pores of the separation membrane and clog (contaminate) the surface and pores of the separation membrane with continuous use of the separation membrane, the filtration performance gradually decreases.
In the membrane separation activated sludge process, an aeration apparatus is provided below the separation membrane in order to suppress a reduction in filtration performance due to contamination of the separation membrane. An aeration device provided below the separation membrane aerates air and the like toward the separation membrane, and separates the deposits on the surface of the separation membrane by the rising flow of the air bubbles and the water to be treated. The energy cost required for aeration by the aeration apparatus is calculated to be about half of the total operating cost of the aeration control system. Therefore, a technique for suppressing the aeration amount by the aeration apparatus is required.
Disclosure of Invention
Problems to be solved by the invention
However, in the operation method of the membrane separation apparatus described in
In view of the above problems, an object of the present invention is to provide an aeration amount control system and an aeration amount control method that can reduce the operating cost of the aeration amount control system.
Means for solving the problems
An aeration amount control system according to the present invention is an aeration amount control system for aerating a separation membrane in a membrane separation tank storing water to be treated, based on a target aeration amount, the aeration amount control system including: a control means for determining a 1 st target aeration amount as a target aeration amount and determining a 2 nd target aeration amount as a target aeration amount after the 1 st target aeration amount is determined; an aeration device for supplying gas based on the target aeration amount determined by the control device to perform aeration; and a measuring device that measures a change amount of an inter-membrane pressure difference of the separation membrane with respect to the gas supplied by the aeration device, wherein the control device determines a value smaller than the 2 nd target aeration amount as the 3 rd target aeration amount when the 1 st change amount of the inter-membrane pressure difference of the separation membrane during the period in which the aeration device performs the aeration based on the 1 st target aeration amount, which is calculated by the measuring device, is larger than the 2 nd change amount of the inter-membrane pressure difference of the separation membrane during the period in which the aeration device performs the aeration based on the 2 nd target aeration amount, which is calculated by the measuring device.
An aeration amount control method according to the present invention is an aeration amount control system for aerating a separation membrane in a membrane separation tank storing water to be treated, based on a target aeration amount, the aeration amount control method including: an aeration amount determination step of determining a 1 st target aeration amount as a target aeration amount, and determining a 2 nd target aeration amount as a target aeration amount after the 1 st target aeration amount is determined; an aeration step of supplying gas based on the target aeration amount determined by the aeration amount determination step to perform aeration; and a variation calculation step of calculating a variation of the inter-membrane pressure difference of the separation membrane with respect to the gas supplied in the aeration step, and determining a value smaller than the 2 nd target aeration amount as the 3 rd target aeration amount, when a 1 st variation of the inter-membrane pressure difference of the separation membrane during the period in which the aeration is performed based on the 1 st target aeration amount calculated by the measurement means is larger than a 2 nd variation of the inter-membrane pressure difference of the separation membrane during the period in which the aeration is performed based on the 2 nd target aeration amount calculated by the measurement means.
Effects of the invention
The aeration amount control system of the present invention can reduce the energy cost required for aeration by increasing or decreasing the target value of the aeration amount, and can reduce the total operating cost of the aeration amount control system.
The aeration amount control method of the present invention can reduce the energy cost required for aeration by increasing or decreasing the target value of the aeration amount, and can reduce the total operating cost of the aeration amount control system.
Drawings
Fig. 1 is a configuration diagram of an aeration amount control system according to
Fig. 2 is a diagram illustrating the configurations of the change amount calculation unit and the control device of the aeration amount control system according to
Fig. 3 is a control flowchart of the aeration amount control system according to
Fig. 4 is an explanatory diagram showing a relationship between a pressure difference between membranes and an aeration amount in the aeration amount control system according to
Fig. 5 is a control flowchart of the aeration amount control system according to
Fig. 6 is a configuration diagram of an aeration amount control system according to
Fig. 7 is a control flowchart of the aeration amount control system according to
Fig. 8 is a configuration diagram of an aeration amount control system according to
Detailed Description
Hereinafter, embodiments of the aeration amount control system and the aeration amount control method disclosed in the present application will be described in detail with reference to the drawings. The embodiments described below are merely examples, and the present invention is not limited to these embodiments.