Study On Scaling Mechanism And Chemical Scale Inhibition Of Gas Field Water Reinjection Pipeline In XX Mining Area

The sewage water pipelines of gas field water surface treatment system have different degrees of scaling in XX mine,of which QL 25 well to QL12 well pipeline the scaling is a prominent problem,due to scaling,this pipeline frequently occur accidents of pipeline jams and explosions,seriously affect the normal production and safe operation of mining area,it is necessary to find the the solving measures.This article takes QL25 to QL12 gas field water reinjection pipelines as the research object.Through water analysis,Finding the water samples include high concentration of scale ion,such as calcium ions and carbonate ions,and predictding the water itself contain tendency of calcium carbonate scale under the conditions of transport conditions but there is no trend of scaling calcium sulfate scale.Through scale analysis,determining the main component of the scale is calcium carbonate.Further laboratory experiments were conducted to study the relevant influencing factors of fouling in gas pipelines,and using the gray correlation method found the temperature,pH,and salinity are the main factors affecting the scaling of pipelines.On the basis of integrating various influencing factors,the mechanism of fouling in the water pipeline of the studied gas field was comprehensively analyzed.Selecting Oddo and Tomson Saturation Index Method and Combining Temperature and Pressure Calculation Models analysis the sacling tendency,It is concluded that the scaling tendency is in good agreement with the experimental results and on-site conditions.Due to the weak chemical scale prevention in the XX mining area,further chemical scale inhibition experiments were carried out.Using bubble method analysis the thermal stability of 8 kinds of scale inhibitors,including calcium ion concentration,alkalinity,and pH adaptability.Five kinds of scale inhibitors with excellent comprehensive performance were initially screened and compounded.A final formulation of 3:2 ratio of PASP and ATMP and a 1:1:3 ratio of ATMP,HPMA and HEDP was determined for the site selection.Through economic analysis finally determined the compounding formula of ATMP,HPMA and HEDP according to a 1:1:3 ratio for selection.The best additive concentration is about 20mg/l.Combined with the previous experimental research results,a specific descaling and anti-scaling solution was proposed.