Abstract: Providing a method of estimating the number of microparticles such as microorganisms in a sample, without performing complicated operations. The method comprises counting by constant flow the number of target microorganisms contained in the sample at a predetermined flow rate, sectioning measurement data obtained as a result of the constant flow counting into a predetermined number of sections by a predetermined unit time for a section, counting the number of sections in which microorganisms are detected and the number of sections in which they are not detected, in the predetermined number of sections; and estimating the number of microorganisms in the sample, by a statistical method from the flow rate of the sample in the constant flow counting step, the predetermined number of sections and the predetermined unit time in the sectioning step, and the number of sections in which microorganisms are detected in the counting step.

Abstract: An inclined sedimentation acceleration apparatus includes an inclined part having a plurality of inclined flow paths through which raw water flows, and side plates disposed on both sides of the inclined part. An upper ridge part of the inclined part is disposed at a height different from that of an upper ridge part of the side plate. Suspended solids are less likely to accumulate on an upper surface of the inclined sedimentation acceleration apparatus.

Abstract: Provided is a water treatment system that prevents overlook and misdetection of abnormal flocculation. The water treatment system includes a mix tank, a flocculation tank, a plurality of floc-particle-diameter measurement devices, a fault detection device that detects abnormal flocculation, and a notification device that notifies occurrence of the abnormal flocculation. The fault detection device includes: a calculator that calculates at least one of a difference and a ratio between particle diameters of floc; a storage that stores therein a tolerable range of at least one of the difference and the ratio between the particle diameters of floc; a determiner that, when the calculated value is within the tolerable range, determines that it is normal, and when the calculated value is outside the tolerable range, determines that it is abnormal; and an outputter that transmits an abnormal flocculation detection signal to the notification device.

Abstract: Providing a method of estimating the number of microparticles such as microorganisms in a sample, performing complicated operations. The method comprises counting by constant flow the number of target microorganisms contained in the sample at a predetermined flow rate, sectioning measurement data obtained as a result of the constant flow counting into a predetermined number of sections by a predetermined unit time for a section, counting the number of sections in which microorganisms are detected and the number of sections in which they are not detected, in the predetermined number of sections; and estimating the number of microorganisms in the sample, by a statistical method from the flow rate of the sample in the constant flow counting step, the predetermined number of sections and the predetermined unit time in the sectioning step, and the number of sections in which microorganisms are detected in the counting step.

Abstract: An inclined sedimentation acceleration apparatus 100 includes an inclined part 10 having a plurality of inclined flow paths 30 through which raw water flows, and side plates 20 disposed on both sides of the inclined part 10. An upper ridge part 15 of the inclined part 10 is disposed at a height different from that of an upper ridge part 21 of the side plate 20. Suspended solids are less likely to accumulate on an upper surface of the inclined sedimentation acceleration apparatus 100.

Abstract: Provided is a water treatment system that prevents overlook and misdetection of abnormal flocculation. The water treatment system includes a mix tank, a flocculation tank, a plurality of floc-particle-diameter measurement devices, a fault detection device that detects abnormal flocculation, and a notification device that notifies occurrence of the abnormal flocculation. The fault detection device includes: a calculator that calculates at least one of a difference and a ratio between particle diameters of floc; a storage that stores therein a tolerable range of at least one of the difference and the ratio between the particle diameters of floc; a determiner that, when the calculated value is within the tolerable range, determines that it is normal, and when the calculated value is outside the tolerable range, determines that it is abnormal; and an outputter that transmits an abnormal flocculation detection signal to the notification device.

Abstract: Provided are a method and an apparatus that enable rapid and automatic determination of the coagulant injection rate in a process of water treatment through coagulation and sedimentation. Using a coagulation analyzer comprising sample tanks 1A to 1D each for keeping a predetermined amount of raw water, a water supply pump 7, water supply/discharge valves 4, 6 for raw water and washing water, mixers 3A to 3D, a coagulant injection unit 21, and a detector 30 for determining the particle size and the particle number of flocs, the time within which the coagulant 20 injected into the sample tanks is dispersed by mixing and the particles begin to agglomerate (agglomeration start time) is determined, and based on the thus-determined agglomeration start time, the coagulant injection rate is determined, or the amount of the coagulant to be injected is controlled.

Abstract: Provided are a method and an apparatus that enable rapid and automatic determination of the coagulant injection rate in a process of water treatment through coagulation and sedimentation. Using a coagulation analyzer comprising sample tanks 1A to 1D each for keeping a predetermined amount of raw water, a water supply pump 7, water supply/discharge valves 4, 6 for raw water and washing water, mixers 3A to 3D, a coagulant injection unit 21, and a detector 30 for determining the particle size and the particle number of flocs, the time within which the coagulant 20 injected into the sample tanks is dispersed by mixing and the particles begin to agglomerate (agglomeration start time) is determined, and based on the thus-determined agglomeration start time, the coagulant injection rate is determined, or the amount of the coagulant to be injected is controlled.

Abstract: Provided are a method and an apparatus that enable rapid and automatic determination of the coagulant injection rate in a process of water treatment through coagulation and sedimentation. Using a coagulation analyzer comprising sample tanks 1A to 1D each for keeping a predetermined amount of raw water, a water supply pump 7, water supply/discharge valves 4, 6 for raw water and washing water, mixers 3A to 3D, a coagulant injection unit 21, and a detector 30 for determining the particle size and the particle number of flocs, the time within which the coagulant 20 injected into the sample tanks is dispersed by mixing and the particles begin to agglomerate (agglomeration start time) is determined, and based on the thus-determined agglomeration start time, the coagulant injection rate is determined, or the amount of the coagulant to be injected is controlled.

Abstract: Provided are a method and an apparatus that enable rapid and automatic determination of the coagulant injection rate in a process of water treatment through coagulation and sedimentation. Using a coagulation analyzer comprising sample tanks 1A to 1D each for keeping a predetermined amount of raw water, a water supply pump 7, water supply/discharge valves 4, 6 for raw water and washing water, mixers 3A to 3D, a coagulant injection unit 21, and a detector 30 for determining the particle size and the particle number of flocs, the time within which the coagulant 20 injected into the sample tanks is dispersed by mixing and the particles begin to agglomerate (agglomeration start time) is determined, and based on the thus-determined agglomeration start time, the coagulant injection rate is determined, or the amount of the coagulant to be injected is controlled.

Abstract: A method of measuring turbidity includes irradiating specimen water with a light beam, using photoelectric conversion means for subjecting to photoelectric conversion the light scattered by fine particles in the specimen water, inputting a pulse signal as an input signal 7 obtainable from the photoelectric conversion whenever the fine particle passes through the light beam so as to measure its peak value in a peak holding circuit 13, obtaining the number concentration of fine particles in the specimen water on the basis of particle diameter divisions according to the measured value, and multiplying the number concentration by an individual coefficient on the basis of the particle diameter divisions in order to obtain the turbidity of the specimen water.