TN100-3R Soil Solution Sampler

1、 Principle and Application of TN100-3R Soil Solution Sampler:
Traditional soil solution sampling often involves on-site collection of soil samples and analysis using immersion solution method, which is labor-intensive and cannot accurately pinpoint the dynamic changes of solutes. TN100-3R soil solution sampler is an instrument for continuously collecting soil solution at a fixed location. It consists of a porous clay tube, a sampling bottle, and an air pump (as shown in Figure 1). Due to the permeability of various solutes through the walls of clay pipes, when buried in soil, soil water/solution can be extracted at fixed intervals to monitor the changes in soil solutes. This method has been widely promoted in fields such as soil fertilizer research, soil pollution, water conservancy departments, and environmental monitoring.
2、 TN100-3R Soil Solution Sampler Instrument Structure:
1. The upper opening of the clay pipe is bonded with a 10mm organic glass protective head, and stainless steel pipes with diameters of 2mm and 4mm are installed respectively. The 2mm diameter pipe extends straight to the bottom of the pipe, and the other pipe extends to the upper end inside the clay pipe. Two polyethylene hoses are connected, and a plastic sleeve is added to the surface of the pipe.
2. Sampling bottle: The sampling bottle adopts a 500ml fine mouthed sample bottle, with the bottle mouth sealed with a rubber stopper, and is equipped with two 2mm diameter stainless steel tubes, one connected to a flexible hose extending to the bottom of the clay tube, and the other connected to the vacuum pump.
3. Vacuum pump: After connecting the vacuum pump to the sampling bottle and clay tube, adjust the negative pressure inside the sampling bottle to -30~-80KPA according to the soil moisture conditions.
3、 TN100-3R soil solution sampler burial method:
Before burial, soak the clay pipe in water to remove air from the pores of the clay pipe.
When burying clay pipes, the diameter of the hole drilled should be slightly larger than the diameter of the clay pipe. The soil taken out after drilling should be mixed into slurry as grout for burying clay pipes. After the clay pipe is penetrated to the predetermined depth, the mud is poured into the hole. After the mud settles, the soil is filled in layers and water is injected into each layer to make the loose soil settle and prevent water from flowing into the gaps during rainfall or irrigation. At the same time, the clay pipe is in good contact with the soil.
The burial method of clay pipes is shown in Figure 2.
4、 TN100-3R soil solution sampler features:
1. There are two flexible hoses installed on the clay tube of the soil solution sampler. One is a pumping pipe that extends straight to the bottom of the clay tube by 3-5mm, and the other is a venting pipe. When the clay tube and the sampling bottle are drawn to a certain negative pressure, the solution around the clay tube will enter the clay tube and the sampling bottle through the wall of the clay tube. When taking water, first open the sealing plug of the venting pipe and release air to compress all the water in the clay tube into the sampling bottle through the pumping pipe, to ensure that it does not mix with the next sampling.
2. The soil solution sampler adopts a polyethylene pipe, and the flexible hose buried in the soil can be bent to avoid the wall effect of rapid water infiltration along the hard pipe during rainfall or irrigation.
3. Easy to use, capable of continuous collection of solutions through fixed-point positioning.
4. A protective sleeve is added to the surface of the buried clay pipe to prevent sun exposure and aging of the hose, thereby extending the service life of the soil solution sampler.
5、 TN100-3R Soil Solution Sampler Remarks:
The length of time required for sampling the solution and the amount of water that can be extracted under a certain negative pressure are determined by the soil moisture content and soil hydraulic conductivity. Therefore, when the soil moisture is high, the required negative pressure is low and the extraction time is short. Conversely, when the soil moisture is low, the required negative pressure is high and the extraction time is long, even several days.
When cleaning the soil solution sampler, a syringe can be used to inject the cleaning solution into the clay tube. The syringe can be used to repeatedly pump the solution, then the contaminated liquid can be sucked out, and finally, water can be injected multiple times to clean it (there is no need to dig out the clay tube during cleaning)