Introduction To Pipeline Problems And Its Solutions

Natural Gas pipelines in use for transportation can or will accumulate rust, corrosion by-product, wax, asphalt, salt, sand and sediment. These solids may originate by carryover from producers. Corrosion by-products, rusting may occur in the lines themselves. Solids may build-up at low spots or naturally occurring low flow areas, as river crossing, intersection, etc. At higher velocities particles may impinge on pipe wall to cause erosion of metal to occur. Build-up on these solids on pipeline walls increase resistance to flow from irregular surface

Corrosion is the most serious problem associated with pipeline maintenance. Substantial dollars are spent each years on prevention, monitoring, inspection and repair of corrosion problems are treated chemically with inhibitors come in several basic types and each performs uniquely in different pipeline conditions

Corrosion occurring in dry gas, for example less than 4-7 lbs. water per MMCF is still a real effect. The best corrosion preventive maintenance in any system is keeping the system clean. Carryover of moisture, water, glycols, methanol, emines and the various solids can initiate corrosion cells from CO2, H2S generated by bacteria, acidity, bridges solids, and oxygen.

Pigging method as well as pigs have evolved to an art science using design to break up, penetrate, clean and remove solids and liquids. By utilising special cleaners designed o penetrate layers and suspended particles, these particles can be removed with pipeline in place. The pigging and cleaning will improve the analysis of in-line inspection tools while the efficiency of flow, by friction reduction, increase product throughput.

Surface must be water wet and dried, not oil wet. These surface are the least flow resistant. These surface are the best preparation for corrosion inhibitor application when used.

Figure 1