Diesel tail gas treatment liquid suspended matter inhibition process

Abstract

The invention discloses a diesel tail gas treatment liquid suspended matter inhibition process which comprises the following steps: mixing urea and high-purity deionized water according to a preset proportion at a first temperature to prepare a urea crude liquid with the urea concentration of 45-52%; carrying out decoloration and multi-stage filtration on the urea crude liquid to obtain a urea clarified liquid; removing positive ions and negative ions in the urea clarified liquid by using ion exchange resin; placing the urea clarified liquor for a first time at a second temperature so that residual metal ions and hydroxyl radicals in the urea clarified liquor are combined to form suspended solids and / or precipitates; carrying out high-speed centrifugal treatment on the urea clarified liquid to remove suspended solids and / or precipitates; adding high-purity deionized water into the urea clarified liquid to dilute the urea concentration of the urea clarified liquid to 32.5% to obtain tail gas treatment liquid; and adding an anti-settling polymerization inhibitor for inhibiting combination of metal ions and hydroxyl into the tail gas treatment liquid. The situation that the tail gas treatment liquid generates suspended solids can be reduced, and the product quality of the tail gas treatment liquid is improved.

Description

technical field [0001] The invention relates to the field of automobile tail gas treatment, in particular to a technique for suppressing suspended matter in diesel tail gas treatment liquid. Background technique [0002] With the increasingly stringent environmental protection regulations, the pollution of diesel engine exhaust pollutants to the environment and the harm to human health have attracted more and more attention. Diesel engine exhaust treatment fluid (commonly known as vehicle urea in China) is widely used in the gas purification system of large diesel vehicles, that is, the reducing agent of the SCR (Selective Catalytic Reduction) system. The principle is to use the exhaust gas treatment fluid and heavy-duty The nitrogen oxides in the exhaust of diesel vehicles such as trucks and buses react to generate N2 and H2O to purify the exhaust, so that the nitrogen oxides discharged can meet the national emission standards of China IV, China V and above. [0003] After...

AI Technical Summary

Problems solved by technology

Existing production and storage environments are difficult to meet the above requirements

Suspended matter (called "algae" in the industry) will breed in the domestically produced tail gas treatment liquid under certain circumstances, and the suspended matter will make the tail gas treatment liquid product difficult to use

Moreover, the time period for the generation of suspended solids fluctuates greatly, ranging from one or two days to several weeks or months, which adds great difficulty to the development of suspended solids removal process

Simply adding filtration steps has little effect

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