The mud water in the sand washing field is a kind of suspended liquid containing a certain amount of fine mud particles in the water. The characteristics of the mud depend on its composition and are related to the local geological conditions. The general characteristics are that the mud is yellowish in appearance, uniform and viscous, for a long time Static without stratification, the specific gravity is between 1.20～1.46 (the proportion of yellow sand is 1.6); the mud content is 20%～30%, and the PH value: 6～7.
The flocculant for sand and gravel wastewater is referred to as PAM, commonly known as flocculant or coagulant. Its molecular formula is [CH—CH]n——CONH2 is a linear water-soluble polymer with a molecular weight of 8-20 million. The appearance of solid products is White or slightly yellow powder, liquid is colorless viscous colloid, easily soluble in water, easily decomposed when the temperature exceeds 120℃. Flocculant for sand washing field.
Types of polymer flocculants, flocculants for sand and gravel wastewater are divided into: anionic, cationic and non-ionic.
Anionic type is mainly used for domestic production water, industrial and urban sewage treatment. It is also suitable for the flocculation and sedimentation of red mud and the separation of mud in the alumina preparation process. The anionic molecular weight is relatively high, mainly used for the precipitation of aqueous suspensions and suspensions. It is difficult to flocculate when acidic and partially acidic solutions contain organic suspensions. In this case, the cationic polymer flocculant can effectively perform flocculation and precipitation, showing its outstanding performance. The use form is 0.1-0.2% aqueous solution, which must be prepared with water with PH≤7. It is easy to be hydrolyzed when mixed into a dilute solution, so it should be used with the preparation or used up the same day, and it is not easy to store for a long time.
Flocculant for sand washing sewage. According to different water quality and production process, the sewage point of the sand washing sewage is different, and the amount of sewage used is different. On-site sampling needs to take the sewage evenly. The flocculant is more suitable. The selected flocculant is small in amount and has good effect. First, the sludge settles quickly, and the circulating water is clear and recycled, Flocculant for sand washing field.
How to use flocculant for sand washing sewage:
1. Dissolve the sand washing flocculant with water into a 0.1%-0.2% concentration aqueous solution before use.
2. Use water that does not contain suspended impurities for dissolution. Tap water is recommended.
3. Mechanical stirring can be used for dilution and stirring, and the number of revolutions is about 200 revolutions per minute; it can be used after stirring for 60 minutes.
The flocculant can be added for sewage treatment in the sand washing industry. When used as sludge sedimentation and dewatering, it is the same as sewage sedimentation. The dissolving liquid is used between 0.1% and 0.2%. After dissolving into a glue-like liquid, it is added to the sludge for mixing. The characteristics of sand washing sewage is khaki, uniform and viscous, long-term standing without stratification, specific gravity: 1120～1146; mud content: 32%～79%; pH value: 6～8. Qualitative sewage experiment In a 1L beaker, add 500mL of the mud water sample at the construction site, add multiple types of flocculants, and the dosage is roughly controlled at the mud separation as the standard. Observe and compare the dehydration of the mud water (the situation of mud water separation) and the mud settled in the lower layer The granularity. Then pour the upper layer of clear water, spread the lower layer of mud on the ground, and observe the stackability of the mud.
The dosage of flocculant for sand washing wastewater treatment is determined according to the small test amount. If the dosage is too large, it will cause waste and adverse effects. If the dosage of flocculant is not enough, it will be difficult for the sand washing mud to precipitate. Therefore, to control the dosage correctly and reasonably, you should first do a small test to determine the dosage. According to this first small test and then large test, under normal circumstances, the sand washing slurry can be successfully separated from the water within a certain period of time. After separation, the supernatant is retained for continued use, and then you can Dewatering the sedimented sand. Generally, the dewatering filter press commonly used in sand washing plants is a belt or plate and frame filter press.