ACRYLONITRILE MANUFACTURE
A method includes reacting, at a first pressure and in the presence of a catalyst, ammonia, oxygen, and a hydrocarbon selected from the group consisting of propane, propylene and isobutylene, and combinations thereof, to provide a reactor effluent stream that includes acrylonitrile. The method includes quenching the reactor effluent stream with a first aqueous stream to provide a quenched stream that includes acrylonitrile. The method includes compressing the quenched stream to provide an effluent compressor stream comprising acrylonitrile, and conveying, at a second pressure, the effluent compressor stream to an absorber. The method includes, in the absorber, absorbing acrylonitrile in a second aqueous stream to provide a rich water comprising acrylonitrile, wherein the absorbing is performed at a pressure greater than the first pressure.
1 . An ammoxidation process comprising:
reacting ammonia, oxygen, and a hydrocarbon selected from the group consisting of propane, propylene, isobutane and isobutylene, and combinations thereof in the presence of a catalyst, at a pressure of about 100 kPa (absolute) or less and a velocity of about 0.5 to about 1.2 meters/second to provide a reactor effluent stream.
2 . The ammoxidation process of claim 1 , wherein the reactor has an internal diameter of about 5 to about 15 meters.
3 . The ammoxidation process of claim 1 , wherein the reactor has an internal diameter of about 9 to about 12 meters.
4 . The ammoxidation process of claim 1 , wherein the reactor has a height (tangent to tangent) of about 10 to about 25 meters.
5 . The ammoxidation process of claim 1 wherein the reacting is conducted at a pressure of about 5 kPa (absolute) to about 100 kPa (absolute).
6 . The ammoxidation process of claim 1 , wherein the velocity is measured at an inlet of the reactor and pressure is measured at an inlet of a cyclone.
7 . The ammoxidation process of claim 1 , wherein the process is effective for providing a conversion rate of hydrocarbon feed to acrylonitrile of about 70% or more.
8 . The ammoxidation process of claim 1 , further comprising quenching the reactor effluent stream with a first aqueous stream to provide a quenched stream that includes acrylonitrile;
compressing the quenched stream to provide an effluent compressor stream that includes acrylonitrile;
conveying, at a pressure of about more than 300 kPa (absolute) to about 500 kPa (absolute), the effluent compressor stream to an absorber; and
in the absorber, absorbing acrylonitrile in a second aqueous stream to provide a rich water that includes acrylonitrile.
9 . The ammoxidation process of claim 8 , further comprising expanding non-absorbed effluent from the absorber to reduce the pressure of the non-absorbed effluent.
10 . The ammoxidation process of claim 9 , wherein the expanding results in a reduction in pressure of the non-absorbed effluent from the absorber to a pressure of about 150 kPa (absolute) or less.
11 . The ammoxidation process of claim 9 , further comprising pre-heating the non-absorbed effluent from the absorber prior to the step of expanding.
12 . The ammoxidation process of claim 9 , wherein the pre-heating raises the temperature of the non-absorbed effluent from a temperature of about 25° C. to about 40° C. to a temperature of about 350° C. or more.
13 . The ammoxidation process of claim 9 , wherein during the step of expanding, the temperature of the non-absorbed effluent is lowered from a temperature of about 300° C. to about 400° C. to a temperature of about 200° C. to about 260° C.
14 . An ammoxidation apparatus comprising:
a reactor configured to react, at a first pressure of about 100 kPa (absolute) or less and in the presence of a catalyst, ammonia, oxygen, and a hydrocarbon selected from the group consisting of propane, propylene and isobutylene, and combinations thereof, to provide a reactor effluent stream comprising acrylonitrile.
15 . The ammoxidation apparatus of claim 14 wherein the reactor is configured to react at a pressure of about 5 kPa (absolute) to about 100 kPa (absolute).
16 . The ammoxidation apparatus of claim 14 further comprising
a quench vessel configured to quench the reactor effluent stream with a first aqueous stream to provide a quenched stream comprising acrylonitrile;
an effluent compressor configured to compress the quenched stream to provide an effluent compressor stream comprising acrylonitrile;
a line configured to convey, at a second pressure, the effluent compressor stream comprising acrylonitrile from the effluent compressor; and
an absorber configured to receive the effluent compressor stream comprising acrylonitrile from the line and allow for absorbing of the acrylonitrile in a second aqueous stream to provide a rich water comprising acrylonitrile.
17 . The ammoxidation apparatus of claim 16 , wherein the effluent compressor is configured to compress the quenched stream to provide an effluent compressor stream comprising acrylonitrile having pressure equal to the second pressure.
18 . The apparatus of claim 16 , wherein the second pressure (absolute) is about 2 to about 12 times greater than the first pressure.
19 . The apparatus of claim 16 , wherein the second pressure is about 300 kPa (absolute) to about 500 kPa (absolute).
20 . The apparatus of claim 16 , wherein the second aqueous stream has a temperature of about 4° C. to about 45° C.
21 . The apparatus of claim 20 , wherein the second aqueous stream has a temperature of about 20° C. to about 45° C.
22 . The apparatus of claim 21 , wherein the second aqueous stream has a flow rate of about 15 to about 20 kg/kg acrylonitrile produced.
23 . The apparatus of claim 11 , further comprising an expander configured to expand non-absorbed effluent from the absorber to reduce a pressure of the non-absorbed effluent.
24 . The apparatus of claim 23 , wherein the expander is configured to reduce the pressure of the non-absorbed effluent from the absorber to a pressure of about 150 kPa (absolute) or less.
25 . The apparatus of claim 23 , further comprising a pre-heater configured to pre-heat the non-absorbed effluent from the absorber prior being expanded in the expander.
26 . The apparatus of claim 25 , wherein the pre-heater is configured to raise the temperature of the non-absorbed effluent from a temperature of about 25° C. to about 40° C. to a temperature of about 350° C. or more.
27 . The apparatus of claim 23 , wherein the expander is configured to lower the temperature of the non-absorbed effluent from a temperature of about 300° C. to about 400° C. to a temperature in the range of about 200° C. to about 260° C.
28 . The apparatus of claim 14 , wherein the reactor has a linear velocity of about 0.5 to about 1.2 meters/second.
29 . The apparatus of claim 14 , wherein the reactor has an internal diameter of about 5 to about 15 meters.
30 . The apparatus of claim 14 , wherein the reactor has a height (tangent to tangent) of about 10 to about 25 meters.