Can chemical industry wastewater be treated with activated sludge process?

Chemical industry wastewater can be treated with a filter press, with a special water purification agent.

The traditional activated sludge treatment method by SICOLAB is suitable for the treatment of wastewater mainly with organic pollutants.

When the ordinary aeration process is adopted, the main design parameters of the reaction tank should be determined according to the test or the operation data of similar sewage, and when there is no data, the following data can be used:

1. The sludge load can be 0 20kg[bod5] (kg[mlss]·d) 0 30kg[bod5] (kg[mlss]·d);

2. The average concentration of suspended solids in the mixture can be 2 0 g [mlss] l and 4 0g [mlss] l;

3. The sludge reflux ratio can be 50 100;

4. The sludge age can be 5d 15d;

5. The sludge yield can be 0 4kg[vss] kg[bod5] 0 6kg[vss] kg[bod5].

3. The volume of the biological reactor tank can be calculated according to the following formula:

1 Calculated according to sludge load:

2 Calculated according to the age of the sludge:

Where: v - effective volume of biological reactor cell (m);

S0 - BOD5 concentration in influent water (mg L);

SE - Effluent BOD5 concentration (mg L);

q - design flow rate of biological reactor (m h);

LS – sludge load;

x - the average concentration of suspended solids in the mixture in the biological reactor (g[mlss] l);

xv - average concentration of volatile suspended solids in the mixture in the biological reactor (g[mlvss] l);

c - sludge age (d);

y——sludge yield coefficient (kg[vss] kg[bod5]);

kd - attenuation coefficient, (d-1);

kd(20)-attenuation coefficient (d-1) at 20, 0 04 0 075;

t - design temperature ( ).

t - temperature coefficient, can be taken 1 02 1 06.

A variety of chemicals can be used for sludge deep dewatering, and the following are the most common chemicals used for ordinary sludge dewatering:

Cationic polyacrylamide: This is a polymer flocculant, which can flocculate small particles in sludge into larger particles through adsorption and bridging, and improve the sedimentation performance and dewatering performance of sludge.

Polyaluminum chloride: This is an inorganic polymer coagulant, which can coagulate with impurities in the sludge to form an insoluble precipitate, so that the water in the sludge is separated.

Lime: Lime can neutralize with the acids in the sludge, adjust the pH value of the sludge, and promote the cohesion and settlement of the sludge.

Diatomaceous earth: Diatomaceous earth has the characteristics of porosity and high specific surface area, which can be used as a filter aid to improve the filtration performance and dewatering performance of sludge.

It should be noted that different kinds of agents are suitable for different sludge properties and treatment requirements, so it is necessary to choose the appropriate agent according to the specific situation in practical applications. For sludge with high organic matter, under the condition that lime is not allowed to be added in the process, it is necessary to customize the organic deep sludge dewatering agent, and adjust the corresponding process parameters to ensure the sludge treatment effect.

Activated sludge treatment wastewater knowledge 02

Summary. Generally speaking, sludge treatment in sewage treatment plants refers to the dewatering and stabilization of sludge, while sludge disposal refers to the composting, landfilling, drying, and heat treatment and final utilization of sludge. For the sludge of the sewage plant, there are generally the following treatment and disposal methods:

Treatment and utilization of sludge in sewage treatment plants.

Generally speaking, sludge treatment in sewage treatment plants refers to the dewatering and stabilization of sludge, while sludge disposal refers to the composting, landfilling, drying, and heat treatment and final utilization of sludge. For the sludge of the sewage plant, there are generally the following treatment and disposal methods:

1. The drying of the drying incineration sludge can control the moisture content of the sludge at 10 40, reduce the volume and weight of the sludge, reduce the transportation cost and landfill cost, and greatly reduce the odor of the sludge. The drying plant can be divided into direct drying and indirect drying, and its energy consumption is related to sludge composition and moisture. Indirect drying (the use of biogas through a heat exchanger) is generally recommended with a vertical drying unit and a fluidized bed process.

2. Sanitary landfill sludge sanitary landfill originated in the 60s of the last century, which is based on the traditional landfill from the perspective of environmental protection, after scientific site selection and necessary site protection treatment, it requires a strict management system and scientific engineering operation methods. At present, it is a relatively mature sludge disposal technology. The basic method is that the municipal sludge is simply sterilized and dumped directly into the lowlands or valleys to create artificial plains.

It has low requirements for sludge treatment technology in the early stage, and digestion and volume reduction can be carried out generally. If it is not digested, it can also be allowed to dry naturally.

3. According to the current economic conditions of China, for most sewage plants (especially a large number of small sewage plants), sludge is a more feasible and realistic plan for farmland. Nitrogen, phosphorus, potassium and trace elements in sludge have a role in increasing crop yield; The organic matter and humus in the sludge are good soil amendments. Sludge is properly thickened, dewatered and transported to the suburbs or neighbouring provinces for use as fertiliser, which is the method used by many sewage treatment plants.

However, farmland fertilization is seasonal, and when mud fertilizer is not needed, the sewage plant will be full of mud, affecting normal operation. As a result, some sewage plants pay farmers to pull the sludge away without asking where it goes, which causes secondary pollution.

A comprehensive treatment method of industrial sludge is to mix, crush and pre-treat industrial sludge, and then the raw materials after aging are extruded and dried, and then sintered into bricks by tunnel kiln or granulated by roller granulators, dried to obtain ceramsite; Described industrial sludge is one or several kinds of printing and dyeing waste, papermaking waste, sewage treatment sludge produced by urban centralized domestic sewage treatment plant, fly ash, slag, construction residue, river cleaning sludge, tunnel and underground engineering sludge.

Here's how:

1) The industrial sludge is dewatered, sent to the shaft kiln dryer, the moisture content is controlled at 5-10%, and it is successively crushed in the primary and secondary crushing, stirred evenly, and then entered the aging warehouse for aging for more than 3 days;

2) After aging, the raw materials are extruded by a double-shaft mixer and a two-stage vacuum hard plastic extruder, and the extruded mud strips are cut into bricks of the required size by a fully automatic blank cutting machine, which are sintered into bricks by the mechanical yard kiln and then sintered into bricks by the tunnel kiln.

Described primary crushing, secondary crushing mode is to adopt roller crushing.

After the raw material after the aging, the granularizer is pelletized by the counter-roller granulation, and the ceramsite is dried, and the ceramsite is prepared.

When the composition of described industrial sludge raw material is more complex, according to the requirements of brick and ceramsite produced, each component in industrial sludge raw material is mixed in proportion, and additives are added, such as curing agent, acid, alkali and the like.