Ethylene waste alkali liquor reduction control method

Abstract

An ethylene waste alkali liquor reduction control method is as follows: controlling component contents of Na2CO3, NaHCO3, NaOH, NaHS and Na2S in a weak alkali section of an ethylene alkaline-wash tower to control waste alkali liquor emission. The component contents are controlled according to the concentration ratio of ethylene cracking gas acid gas CO2 and H2S, and are treated differently according to three conditions. On the basis of improving of the analysis accuracy and precision of waste alkali liquor components, operation procedures are simplified, controllability of the ethylene device alkaline-wash tower is improved, alkali-saving emission-reducing cleaner production process can be realized, and the method belongs to the field of sewage treatment.

Description

technical field

[0001] The invention relates to a treatment technology for ethylene waste lye, in particular to a method for reducing the amount of waste lye in an ethylene alkali washing tower. It belongs to the field of sewage treatment. Background technique

[0002] Ethylene is an important basic organic chemical raw material. It is the basic raw material industry for the production of three major synthetic materials and organic chemical products. At present, about 75% of petrochemical products are produced from ethylene, and its development level generally represents the strength of a country's petrochemical industry. The development of the world's ethylene industry started in the 1930s with the research on the high-temperature cracking of petroleum hydrocarbons to produce ethylene technology, and in the early 1940s, a device for the production of olefins by tube furnace cracking was built. After nearly 70 years of development, the method of producing ethylene by therm...

Examples

Embodiment 1

[0051] It is known that when the raw material of an ethylene alkali scrubber is a fixed low-carbon component, the acid gas at the inlet of the pyrolysis gas of the alkali scrubber: CO 2 and H 2 S mass concentration is 130mg / L and 60mg / L respectively, CO 2 Mass percent concentration greater than 2 times H 2 C is met when S mass percentage concentration CO2 ≥2C H2S , Take 10g of the light yellow-green waste lye sample of the weak alkali section of the alkali washing tower in a 100ml volumetric flask, shake to a constant volume and set aside.

[0052] 1) Titration V1: Take 2ml of the diluted lye sample and put it into the Erlenmeyer flask, add 2~3 drops of 1% phenolphthalein indicator, add 10ml of distilled water, and titrate with 0.1000M standard hydrochloric acid solution until the red color disappears immediately and the titration jumps Point, write down the consumed standard hydrochloric acid volume V1 = 2.25ml.

[0053] 2) After finishing the titration of V1, immediatel...

Embodiment 2

[0064] It is known that when the raw material of an ethylene alkali scrubber is a fixed low-carbon component, the acid gas at the inlet of the pyrolysis gas of the alkali scrubber: CO 2 and H 2 S mass concentrations were 60mg / L and 150mg / L, H 2 S mass percentage concentration is greater than CO 2 satisfies C CO2 ≤2C H2S , Take 5g of the light yellow-green waste lye sample of the weak alkali section of the alkali washing tower in a 100ml volumetric flask, add water to the mark, shake well and set aside.

[0065] 1) Titration V1: Take 5ml of the diluted waste lye sample and put it into a 0.0% Erlenmeyer flask, add 2 to 3 drops of 0.1% grass phenol blue indicator, add 10ml of distilled water, and titrate to blue just with 0.1000M standard hydrochloric acid solution Once it disappears, record the consumed standard hydrochloric acid volume V1 = 4.46ml.

[0066] 2) After finishing the titration of V1, immediately add 10ml of 40% formaldehyde solution, the sample is blue, then t...

technical field

[0001] The invention relates to a treatment technology for ethylene waste lye, in particular to a method for reducing the amount of waste lye in an ethylene alkali washing tower. It belongs to the field of sewage treatment. Background technique

[0002] Ethylene is an important basic organic chemical raw material. It is the basic raw material industry for the production of three major synthetic materials and organic chemical products. At present, about 75% of petrochemical products are produced from ethylene, and its development level generally represents the strength of a country's petrochemical industry. The development of the world's ethylene industry started in the 1930s with the research on the high-temperature cracking of petroleum hydrocarbons to produce ethylene technology, and in the early 1940s, a device for the production of olefins by tube furnace cracking was built. After nearly 70 years of development, the method of producing ethylene by therm...

Examples

Embodiment 1

[0051] It is known that when the raw material of an ethylene alkali scrubber is a fixed low-carbon component, the acid gas at the inlet of the pyrolysis gas of the alkali scrubber: CO 2 and H 2 S mass concentration is 130mg / L and 60mg / L respectively, CO 2 Mass percent concentration greater than 2 times H 2 C is met when S mass percentage concentration CO2 ≥2C H2S , Take 10g of the light yellow-green waste lye sample of the weak alkali section of the alkali washing tower in a 100ml volumetric flask, shake to a constant volume and set aside.

[0052] 1) Titration V1: Take 2ml of the diluted lye sample and put it into the Erlenmeyer flask, add 2~3 drops of 1% phenolphthalein indicator, add 10ml of distilled water, and titrate with 0.1000M standard hydrochloric acid solution until the red color disappears immediately and the titration jumps Point, write down the consumed standard hydrochloric acid volume V1 = 2.25ml.

[0053] 2) After finishing the titration of V1, immediatel...

Embodiment 2

[0064] It is known that when the raw material of an ethylene alkali scrubber is a fixed low-carbon component, the acid gas at the inlet of the pyrolysis gas of the alkali scrubber: CO 2 and H 2 S mass concentrations were 60mg / L and 150mg / L, H 2 S mass percentage concentration is greater than CO 2 satisfies C CO2 ≤2C H2S , Take 5g of the light yellow-green waste lye sample of the weak alkali section of the alkali washing tower in a 100ml volumetric flask, add water to the mark, shake well and set aside.

[0065] 1) Titration V1: Take 5ml of the diluted waste lye sample and put it into a 0.0% Erlenmeyer flask, add 2 to 3 drops of 0.1% grass phenol blue indicator, add 10ml of distilled water, and titrate to blue just with 0.1000M standard hydrochloric acid solution Once it disappears, record the consumed standard hydrochloric acid volume V1 = 4.46ml.

[0066] 2) After finishing the titration of V1, immediately add 10ml of 40% formaldehyde solution, the sample is blue, then t...

Images