無機鹽混凝劑水解是吸熱反應，低溫水混凝劑水解困難；低溫水的粘度大，使水中雜質顆粒的布朗運動強度減弱，碰撞機會減少，不利于膠體脫穩凝聚，同時還影響絮凝體的成長。

　　當水中投加混凝劑后，因混凝劑發生水解使水中的H＋濃度增加，從而導致水的pH值下降，阻礙了水解的進行。要使pH值保持在較佳范圍以內，水中應有足夠的堿性物質與H＋中和。天然水中均含有一定堿度(通常是HCO3-)，可以中和混凝劑水解過程產生的H＋，對pH值有緩沖作用。

　　水中SS顆粒大小、帶電性都會影響混凝效果。一般來說，粒徑細小而均一，其混凝效果較差，水中顆粒濃度低，顆粒碰撞機率小，對混凝不利；當濁度很大時，為使水中膠體脫穩，當水中存在大量有機物時，能被粘土顆粒吸附，從而改變了原有膠體顆粒的表面特性，使膠體顆粒更加穩定，將嚴重影響混凝效果，此時必須向水中投加氧化劑，破壞有機物的作用，提升混凝效果。

The hydrolysis of inorganic salt coagulants is an endothermic reaction, and the hydrolysis of coagulants in low temperature water is difficult; the viscosity of low temperature water is large, which weakens the Brownian motion of impurity particles in the water and reduces the chance of collision, which is not conducive to colloid destabilization and coagulation, and also affects flocculation. body growth.

When the coagulant is added to the water, the H+ concentration in the water increases due to the hydrolysis of the coagulant, which causes the pH value of the water to drop and hinders the hydrolysis. To keep the pH value within the preferred range, there should be enough alkaline substances in the water to neutralize H+. Natural water contains a certain degree of alkalinity (usually HCO3-), which can neutralize the H+ generated during the hydrolysis of the coagulant and has a buffering effect on the pH value.

SS particle size and electrification in water will affect the coagulation effect. Generally speaking, the particle size is small and uniform, the coagulation effect is poor, the particle concentration in the water is low, and the probability of particle collision is small, which is not good for coagulation; when the turbidity is large, in order to destabilize the colloid in the water, when there is a large amount of In the case of organic matter, it can be adsorbed by clay particles, thus changing the surface characteristics of the original colloidal particles, making the colloidal particles more stable, which will seriously affect the coagulation effect. Effect.