Dehydration

TEG Dehydration

Natural gas pipelines usually require water content to be 7 lbs/mmcf or less.  Typically, glycol (especially tri-ethylene Glycol, TEG) is used to dehydrate natural gas to satisfy this requirement.  Dehydration is commonly installed downstream of compression and amine treating, or upstream of gas processing.  KMT provides dehydrators for volumes from about 1 MMscfd up to about 400 MMscfd.  Out modular skids reduce installation cost and duration.
 
In a glycol contactor (absorber) column, water vapor is absorbed from the gas under high pressure. In a glycol regeneration skid, conditions of low pressure and high temperature liberate water from the TEG.  Finally, the cooled, lean glycol is returned to the TEG absorber, completing the cycle.
 
Our units can use instrument gas or compressed air and can use electric or pneumatic glycol solution pumps.  Our standard skids include burner management systems (BMS) and other environmental/safety devices.  We typically build containment into our structural skids, consisting of a solid steel drain pan, sloped to a skid drain connection.  KMT can provide treating and dehydration skids with integrated PLC devices to reduce cost while enhancing runtime.

CO2 Dehydration

Before carbon dioxide can be compressed, transported via pipeline, and ultimately injected into a producing oil field for Enhanced Oil Recovery (EOR) or into a disposal well for Carbon Capture and Sequestration (CCS), it must be dehydrated to prevent water condensation and hydrate formation. Incompressible liquids, such as water, will damage compressors. Condensed water in pipelines reacts with carbon dioxide to form carbonic acid that corrodes steel pipes. CO2 pipeline operators impose minimum quality requirements in order to control corrosion and hydrates. For example, Kinder Morgan CO2 Pipeline specifications require that the product shall contain no free water, and shall not contain more than 30 pounds of water per million standard cubic feet (lb/MMSCF) in the vapor phase.

A typical TEG Dehydrator consists of a contactor/absorber column to remove water vapor from the CO2 vapor and a regeneration system.  A filter separator upstream and a scrubber downstream of the contactor can reduce glycol contamination and TEG carryover, respectively. The glycol (TEG) regeneration system typically consists of a flash tank, carbon filter, solids filters, Lean/Rich heat exchangers, booster pumps, solution pumps, reboiler (heater), surge tank, still column (complete with a reflux condenser coil), and TEG cooler. We can add optional items such as a reboiler sparging system (to increase TEG purity) and BTEX emissions control (BTEX condenser, BTEX drum, and BTEX pump) if needed.
 
Kinder Morgan Treating designs and builds dehydrators for CO2 service at our certified ISO-9001 and ASME Code fabrication shop in Odessa, Texas. We build carbon steel, stainless steel, and cladded components; packed or trayed columns with vessel diameters from 18” to 144” ID/OD, and dehydrator heat duties from 0.250 MMBTU/hr to 6 MMBTU/hr. We offer systems with direct-fired, heat medium (hot oil or steam) and electric immersion heaters. Our specialty is fully automated dehydration systems with electric pumps, burner management systems (BMS), and Allen Bradley programmable logic controllers (PLC).  We can add a moisture analyzer, gas chromatograph, or other controls and safety/monitoring devices.

BTEX Elimination Units

Our BTEX elimination units use finned-tube exchangers to capture and recycle BTEX and VOC vapors from dehydration plants. These are closed-loop systems that eliminate BTEX emissions and also reduce fuel consumption. These units can be leased separately or with one of our TEG dehydration units.