The residue of traditional Chinese medicine extracted by pharmaceutical factories in production is commonly called Chinese medicine residue. As the national and social requirements for environmental protection are higher and higher, Chinese medicinal residue is no longer discarded as the original treatment method. Usually, it can only be treated by incineration of boiler. As there is a lot of liquid in the residue, the combustion cost is relatively high. The screw press is used to squeeze and dehydrate the Chinese medicine residue. It not only recovered the loss of liquid, but also greatly reduced the cost of raw materials’ burning, which saved time, effort and the capital investment.
According to the characteristics of sludge in the pharmaceutical industry, we optimized the following designs of multi plate screw press, which brought the following corresponding advantages.
1.A new kind of inorganic special screw shaft was developed. By adjusting the distance between the spiral blades, reducing the dead zone between the shaft and the spiral blade and other methods, the pressure inside the cavity of filtration body increases more gently. Thus, the problem of easy clogging of sludge in pharmaceutical industry is alleviated.
2.It adopts the new type of plate configuration, which reduces the gap of the plates and ensures that most of the flocculation are trapped in the cavity. As a result, the solid and liquid are separated without clogging the shaft.
3.According to the different waste water treatment processes adopted by the pharmaceutical industry (such as coagulation method, membrane separation method, air floatation method, etc.), we innovate the flocculation mixing tank, flexibly adjust the flocculation reaction time of the screw press, and ensure that the sludge entering the dewatering body is in the best flocculation state.
4.Considering the characteristics of high toxicity, obvious smell and great harm to human body of pharmaceutical sludge, the press is designed in a structure of completely sealing. Now the site is cleaner. At the same time, it is equipped with pneumatic spring observation window, which is easy to observe the internal running state of the machine;
5.According to the characteristics of the pharmaceutical sludge industry, each parts adopts anti-corrosion materials or anti-corrosion treatment, which extends the service life and makes the operation safer and more stable.
6.The filtrate of treated pharmaceutical sludge is clear, and the moisture content of sludge can be reduced to about 80%. The volume and weight of the sludge decrease significantly after dewatering, which achieves significant reduction and reduces the customer's sludge transportation cost.
Application of super high pressure filter press in titanium dioxide sulfate production process
A lot of acid waste water will be produced in the production of titanium dioxide sulfate. Basically, it is to use first - class neutralization of limestone and second - class adjustment of lime emulsion to reach the purpose of qualified discharge of pH value. During this period, large amounts of calcium sulfate and iron hydroxide precipitate will be produced. Because the color presents brick red, so we calls it red gypsum. For the filtration and separation of red gypsum, many enterprises use chamber filter. After filtration, red gypsum has a high moisture content, which is difficult to stack and needs high recovery cost. For the sludge after air burst in wastewater treatment station, the super high pressure filter press is used to press and dewater. Thus, red gypsum with a solid content of about 55% can be obtained, which can be stacked and treated.
A large number of mechanical and colloidal fine particles from acid solution of titanium formed flocculation agglomeration and sedimentation under the combined action of inorganic and organic flocculating agents. Some titanium liquid is mixed in the sediment, which must be separated and recovered by solid and liquid separation device. It is called "sludge treatment process" in titanium dioxide sulfate. The sludge is often treated by the chamber filter press, which only forms the liquid and solid separation state through the mechanical extrusion of the filter plate, so there are big drawbacks. On the one hand, the liquid-solid separation is extremely incomplete, resulting in the waste of titanium liquid and low yield. On the other hand, the high strength extrusion makes more damage to the filter plate .The super high pressure filter press is applied to the sludge treatment process. The separation efficiency of titanium liquid is increased by 30% ~ 50%, and the amount of liquid is greatly reduced, which is convenient for transportation and treatment.
Mechanical impurities and colloidal particles are basically separated in the sedimentation process, and there are also fine particles and impurities that have not been clarified, which need to be separated and removed through the control filtration process. The control filtration process generally uses the frame filter press and the chamber filter press to filter titanium liquid. The filter cloth is covered with a layer of filter aids (charcoal powder, diatomaceous earth, wood powder). The titanium liquid intercepts the impurity particles through the filter aid and cloth. Both the frame filter press and the chamber filter press have small filtration area, which leads to the general leakage of titanium liquid. When filtering, the cavity of filter plate is easily filled with titanium liquid, which makes the filtration pressure rise rapidly and the yield is low. The impurities forced through the filter plate are high and affect the quality of titanium liquid. The above defects can be completely overcome and the quality of the titanium liquid can be guaranteed by replacing the existing frame filter press or chamber filter press with the super high pressure filter press.