Apparatus and method for continuous monitoring and detection of microplastics in water

An autosampler apparatus for automated monitoring and detection of microplastics present in water, the autosampler apparatus comprising:

• an autosampler body including:
• a top plate having a top plate edge, a bottom plate having a bottom plate edge which is coextensive with the top plate edge, a vertical wall extending between the top and bottom plates, and extending at least partially along the coextensive top plate edge and bottom plate edge;
• and three or more legs securely mounted to the autosampler body and which support and maintain the bottom plate of the autosampler a distance above ground level or other surface upon which the autosampler rests;
• a vertical shaft rotatably disposed within the autosampler body, wherein the vertical shaft extends at least from the top plate to the bottom plate and defines an axis of rotation within the autosampler body;
• a rotatable carousel disposed within the autosampler body and comprising a carousel plate having peripheral edge and a geometric center to which the vertical shaft is statically affixed, intermediate the top plate and bottom plate of the autosampler body, for rotating the carousel within the autosampler body, wherein the carousel plate has a plurality of sample openings therethrough which are distributed symmetrically and evenly around and proximate to the peripheral edge;
• a rotation motor which is mounted on the autosampler body, is in communication with the vertical shaft, and is capable of rotating the rotatable carousel via the vertical shaft;
• and
• 12 or more plastic pellet and powder capture nets (P3CNs) for receiving and filtering water which is provided thereto to detect the presence of microplastics in the water, wherein each P3CN has an upstream inlet end and an opposite downstream end, wherein each P3CN is mounted by its upstream inlet end to, in fluid communication with, a respective one of the plurality of sample openings, proximate the peripheral edge of the carousel plate and extending vertically downward from the carousel plate.

An autosampler apparatus for automated monitoring and detection of microplastics present in water, the autosampler apparatus comprising:

• an autosampler body including:
• a top plate having a top plate edge, a bottom plate having a bottom plate edge which is coextensive with the top plate edge, a vertical wall extending between the top and bottom plates, and extending at least partially along the coextensive top plate edge and bottom plate edge;
• and three or more legs securely mounted to the autosampler body and which support and maintain the bottom plate of the autosampler a distance above ground level or other surface upon which the autosampler rests;
• a vertical shaft rotatably disposed within the autosampler body, wherein the vertical shaft extends at least from the top plate to the bottom plate and defines an axis of rotation within the autosampler body;
• a rotatable carousel disposed within the autosampler body and comprising a carousel plate having peripheral edge and a geometric center to which the vertical shaft is statically affixed, intermediate the top plate and bottom plate of the autosampler body, for rotating the carousel within the autosampler body, wherein the carousel plate has a plurality of sample openings therethrough which are distributed symmetrically and evenly around and proximate to the peripheral edge;
• a rotation motor which is mounted on the autosampler body, is in communication with the vertical shaft, and is capable of rotating the rotatable carousel via the vertical shaft;
• a carousel locking system capable of pausing rotation of the carousel by intermittently and sequentially locking the carousel plate for a predetermined period of sampling time, wherein the carousel locking system comprises a mating feature on the carousel plate, a locking feature which is movable between an unlocked position in which the carousel is free to rotate and a locked position in which rotation of the carousel plate is prevented;
• and
• a plurality of plastic pellet and powder capture nets (P3CNs) for receiving and filtering water which is provided thereto to detect the presence of microplastics in the water, wherein each P3CN has an upstream inlet end and an opposite downstream end, wherein each P3CN is mounted by its upstream inlet end to, in fluid communication with, a respective one of the plurality of sample openings, proximate the peripheral edge of the carousel plate and extending vertically downward from the carousel plate.

A method for sampling and detecting the presence of microplastics in water using an autosampler apparatus comprising:

• an autosampler body and a rotatable carousel disposed therein and having a carousel plate;
• the carousel plate having a plurality of sample openings therethrough which are distributed symmetrically and evenly around and proximate to a peripheral edge of the carousel plate, wherein the carousel plate is rotated by rotation of a vertical shaft statically affixed to a geometric center thereof, using a rotation motor which is mounted on the autosampler body;
• and
• a plurality of plastic pellet and powder capture nets (P3CNs) for receiving and filtering water which is provided thereto to detect the presence of microplastics in the water, wherein the plurality of P3CNs comprises a total of N P3CNs and N equals two or more, each P3CN having an upstream inlet end and an opposite downstream end, wherein each P3CN is mounted by its upstream inlet end to, in fluid communication with, a respective one of the plurality of sample openings, each P3CN extending vertically downward from the carousel plate,
• the method comprising:
• confirming that the autosampler apparatus is positioned proximate an open end of a conduit, wherein the open end is aligned with an accessible one of the plurality of sample openings and the corresponding one of the plurality of P3CNs mounted thereto which is now the aligned P3CN;
• delivering water from a water source, at a selected flowrate, through the open end of the conduit, into the upstream inlet end of the aligned P3CN, through the aligned P3CN, and allowing filtered water to exit the downstream end of the aligned P3CN;
• automatically sampling the water, in predetermined water sample sizes and quantity of water samples for the presence of microplastics, over a selected total sampling period, by performing the sequential steps of:
• pausing rotation of the carousel for a predetermined period of sampling time;
• after passage of the selected sample time, rotating the carousel until a next one of the plurality of P3CNs, which is adjacent the aligned P3CN, is now aligned with the open end of the conduit and now becomes the aligned P3CN;
• repeating the sequential steps of pausing rotation and rotating the carousel a number of times equal to (N−1), so that each of the N number of P3CNs is used for filtering the water over the selected total sampling period.